InVivoPlus anti-mouse CD8α
Product Details
The 2.43 monoclonal antibody reacts with mouse CD8α. The CD8 antigen is a transmembrane glycoprotein that acts as a co-receptor for the T cell receptor (TCR). Like the TCR, CD8 binds to class I MHC molecules displayed by antigen presenting cells (APC). CD8 is primarily expressed on the surface of cytotoxic T cells, but can also be found on thymocytes, natural killer cells, and some dendritic cell subsets. CD8 most commonly exists as a heterodimer composed of one CD8α and one CD8β chain however, it can also exist as a homodimer composed of two CD8α chains. Both the CD8α and CD8β chains share significant homology to immunoglobulin variable light chains. The molecular weight of each CD8 chain is approximately 34 kDa. The 2.43 antibody exhibits depleting activity when used in vivo.Specifications
| Isotype | Rat IgG2b, κ |
|---|---|
| Recommended Isotype Control(s) | InVivoPlus rat IgG2b isotype control, anti-keyhole limpet hemocyanin |
| Recommended Dilution Buffer | InVivoPure pH 7.0 Dilution Buffer |
| Conjugation | This product is unconjugated. Conjugation is available via our Antibody Conjugation Services. |
| Immunogen | Mouse CTL clone L3 |
| Reported Applications |
in vivo CD8+ T cell depletion Western blot |
| Formulation |
PBS, pH 7.0 Contains no stabilizers or preservatives |
| Endotoxin* |
<1EU/mg (<0.001EU/μg) Determined by LAL gel clotting assay |
| Aggregation* |
<5% Determined by SEC |
| Purity |
>95% Determined by SDS-PAGE |
| Sterility | 0.2 µm filtration |
| Production | Purified from cell culture supernatant in an animal-free facility |
| Purification | Protein G |
| RRID | AB_1125541 |
| Molecular Weight | 150 kDa |
| Murine Pathogen Tests* |
Ectromelia/Mousepox Virus: Negative Hantavirus: Negative K Virus: Negative Lactate Dehydrogenase-Elevating Virus: Negative Lymphocytic Choriomeningitis virus: Negative Mouse Adenovirus: Negative Mouse Cytomegalovirus: Negative Mouse Hepatitis Virus: Negative Mouse Minute Virus: Negative Mouse Norovirus: Negative Mouse Parvovirus: Negative Mouse Rotavirus: Negative Mycoplasma Pulmonis: Negative Pneumonia Virus of Mice: Negative Polyoma Virus: Negative Reovirus Screen: Negative Sendai Virus: Negative Theiler’s Murine Encephalomyelitis: Negative |
| Storage | The antibody solution should be stored at the stock concentration at 4°C. Do not freeze. |
Additional Formats
Recommended Products
-
Recommended Isotype Control(s)
InVivoPlus rat IgG2b isotype control, anti-keyhole limpet hemocyanin
-
Recommended Dilution Buffer
InVivoPure pH 7.0 Dilution Buffer
in vivo CD8+ T cell depletion
Balogh, K. N., et al. (2018). "Macrophage Migration Inhibitory Factor protects cancer cells from immunogenic cell death and impairs anti-tumor immune responses" PLoS One 13(6): e0197702. PubMed
The Macrophage Migration Inhibitory Factor (MIF) is an inflammatory cytokine that is overexpressed in a number of cancer types, with increased MIF expression often correlating with tumor aggressiveness and poor patient outcomes. In this study, we aimed to better understand the link between primary tumor expression of MIF and increased tumor growth. Using the MMTV-PyMT murine model of breast cancer, we observed that elevated MIF expression promoted tumor appearance and growth. Supporting this, we confirmed our previous observation that higher MIF expression supported tumor growth in the 4T1 murine model of breast cancer. We subsequently discovered that loss of MIF expression in 4T1 cells led to decreased cell numbers and increased apoptosis in vitro under reduced serum culture conditions. We hypothesized that this increase in cell death would promote detection by the host immune system in vivo, which could explain the observed impairment in tumor growth. Supporting this, we demonstrated that loss of MIF expression in the primary tumor led to an increased abundance of intra-tumoral IFNgamma-producing CD4+ and CD8+ T cells, and that depletion of T cells from mice bearing MIF-deficient tumors restored growth to the level of MIF-expressing tumors. Furthermore, we found that MIF depletion from the tumor cells resulted in greater numbers of activated intra-tumoral dendritic cells (DCs). Lastly, we demonstrated that loss of MIF expression led to a robust induction of a specialized form of cell death, immunogenic cell death (ICD), in vitro. Together, our data suggests a model in which MIF expression in the primary tumor dampens the anti-tumor immune response, promoting tumor growth.
in vivo CD8+ T cell depletion
Li, J., et al. (2018). "Co-inhibitory Molecule B7 Superfamily Member 1 Expressed by Tumor-Infiltrating Myeloid Cells Induces Dysfunction of Anti-tumor CD8(+) T Cells" Immunity 48(4): 773-786 e775. PubMed
The molecular mechanisms whereby CD8(+) T cells become “exhausted” in the tumor microenvironment remain unclear. Programmed death ligand-1 (PD-L1) is upregulated on tumor cells and PD-1-PD-L1 blockade has significant efficacy in human tumors; however, most patients do not respond, suggesting additional mechanisms underlying T cell exhaustion. B7 superfamily member 1 (B7S1), also called B7-H4, B7x, or VTCN1, negatively regulates T cell activation. Here we show increased B7S1 expression on myeloid cells from human hepatocellular carcinoma correlated with CD8(+) T cell dysfunction. B7S1 inhibition suppressed development of murine tumors. Putative B7S1 receptor was co-expressed with PD-1 but not T cell immunoglobulin and mucin-domain containing-3 (Tim-3) at an activated state of early tumor-infiltrating CD8(+) T cells, and B7S1 promoted T cell exhaustion, possibly through Eomes overexpression. Combinatorial blockade of B7S1 and PD-1 synergistically enhanced anti-tumor immune responses. Collectively, B7S1 initiates dysfunction of tumor-infiltrating CD8(+) T cells and may be targeted for cancer immunotherapy.
in vivo CD8+ T cell depletion
Moynihan, K. D., et al. (2016). "Eradication of large established tumors in mice by combination immunotherapy that engages innate and adaptive immune responses" Nat Med. doi : 10.1038/nm.4200. PubMed
Checkpoint blockade with antibodies specific for cytotoxic T lymphocyte-associated protein (CTLA)-4 or programmed cell death 1 (PDCD1; also known as PD-1) elicits durable tumor regression in metastatic cancer, but these dramatic responses are confined to a minority of patients. This suboptimal outcome is probably due in part to the complex network of immunosuppressive pathways present in advanced tumors, which are unlikely to be overcome by intervention at a single signaling checkpoint. Here we describe a combination immunotherapy that recruits a variety of innate and adaptive immune cells to eliminate large tumor burdens in syngeneic tumor models and a genetically engineered mouse model of melanoma; to our knowledge tumors of this size have not previously been curable by treatments relying on endogenous immunity. Maximal antitumor efficacy required four components: a tumor-antigen-targeting antibody, a recombinant interleukin-2 with an extended half-life, anti-PD-1 and a powerful T cell vaccine. Depletion experiments revealed that CD8+ T cells, cross-presenting dendritic cells and several other innate immune cell subsets were required for tumor regression. Effective treatment induced infiltration of immune cells and production of inflammatory cytokines in the tumor, enhanced antibody-mediated tumor antigen uptake and promoted antigen spreading. These results demonstrate the capacity of an elicited endogenous immune response to destroy large, established tumors and elucidate essential characteristics of combination immunotherapies that are capable of curing a majority of tumors in experimental settings typically viewed as intractable.
in vivo CD8+ T cell depletion
Voron, T., et al. (2015). "VEGF-A modulates expression of inhibitory checkpoints on CD8+ T cells in tumors" J Exp Med 212(2): 139-148. PubMed
Immune escape is a prerequisite for tumor development. To avoid the immune system, tumors develop different mechanisms, including T cell exhaustion, which is characterized by expression of immune inhibitory receptors, such as PD-1, CTLA-4, Tim-3, and a progressive loss of function. The recent development of therapies targeting PD-1 and CTLA-4 have raised great interest since they induced long-lasting objective responses in patients suffering from advanced metastatic tumors. However, the regulation of PD-1 expression, and thereby of exhaustion, is unclear. VEGF-A, a proangiogenic molecule produced by the tumors, plays a key role in the development of an immunosuppressive microenvironment. We report in the present work that VEGF-A produced in the tumor microenvironment enhances expression of PD-1 and other inhibitory checkpoints involved in CD8(+) T cell exhaustion, which could be reverted by anti-angiogenic agents targeting VEGF-A-VEGFR. In view of these results, association of anti-angiogenic molecules with immunomodulators of inhibitory checkpoints may be of particular interest in VEGF-A-producing tumors.
in vivo CD8+ T cell depletion
Vanpouille-Box, C., et al. (2015). "TGFbeta Is a Master Regulator of Radiation Therapy-Induced Antitumor Immunity" Cancer Res 75(11): 2232-2242. PubMed
T cells directed to endogenous tumor antigens are powerful mediators of tumor regression. Recent immunotherapy advances have identified effective interventions to unleash tumor-specific T-cell activity in patients who naturally develop them. Eliciting T-cell responses to a patient’s individual tumor remains a major challenge. Radiation therapy can induce immune responses to model antigens expressed by tumors, but it remains unclear whether it can effectively prime T cells specific for endogenous antigens expressed by poorly immunogenic tumors. We hypothesized that TGFbeta activity is a major obstacle hindering the ability of radiation to generate an in situ tumor vaccine. Here, we show that antibody-mediated TGFbeta neutralization during radiation therapy effectively generates CD8(+) T-cell responses to multiple endogenous tumor antigens in poorly immunogenic mouse carcinomas. Generated T cells were effective at causing regression of irradiated tumors and nonirradiated lung metastases or synchronous tumors (abscopal effect). Gene signatures associated with IFNgamma and immune-mediated rejection were detected in tumors treated with radiation therapy and TGFbeta blockade in combination but not as single agents. Upregulation of programmed death (PD) ligand-1 and -2 in neoplastic and myeloid cells and PD-1 on intratumoral T cells limited tumor rejection, resulting in rapid recurrence. Addition of anti-PD-1 antibodies extended survival achieved with radiation and TGFbeta blockade. Thus, TGFbeta is a fundamental regulator of radiation therapy’s ability to generate an in situ tumor vaccine. The combination of local radiation therapy with TGFbeta neutralization offers a novel individualized strategy for vaccinating patients against their tumors.
in vivo CD8+ T cell depletion
Yamada, D. H., et al. (2015). "Suppression of Fcgamma-receptor-mediated antibody effector function during persistent viral infection" Immunity 42(2): 379-390. PubMed
Understanding how viruses subvert host immunity and persist is essential for developing strategies to eliminate infection. T cell exhaustion during chronic viral infection is well described, but effects on antibody-mediated effector activity are unclear. Herein, we show that increased amounts of immune complexes generated in mice persistently infected with lymphocytic choriomeningitis virus (LCMV) suppressed multiple Fcgamma-receptor (FcgammaR) functions. The high amounts of immune complexes suppressed antibody-mediated cell depletion, therapeutic antibody-killing of LCMV infected cells and human CD20-expressing tumors, as well as reduced immune complex-mediated cross-presentation to T cells. Suppression of FcgammaR activity was not due to inhibitory FcgammaRs or high concentrations of free antibody, and proper FcgammaR functions were restored when persistently infected mice specifically lacked immune complexes. Thus, we identify a mechanism of immunosuppression during viral persistence with implications for understanding effective antibody activity aimed at pathogen control.
in vivo CD8+ T cell depletion
Twyman-Saint Victor, C., et al. (2015). "Radiation and dual checkpoint blockade activate non-redundant immune mechanisms in cancer" Nature 520(7547): 373-377. PubMed
Immune checkpoint inhibitors result in impressive clinical responses, but optimal results will require combination with each other and other therapies. This raises fundamental questions about mechanisms of non-redundancy and resistance. Here we report major tumour regressions in a subset of patients with metastatic melanoma treated with an anti-CTLA4 antibody (anti-CTLA4) and radiation, and reproduced this effect in mouse models. Although combined treatment improved responses in irradiated and unirradiated tumours, resistance was common. Unbiased analyses of mice revealed that resistance was due to upregulation of PD-L1 on melanoma cells and associated with T-cell exhaustion. Accordingly, optimal response in melanoma and other cancer types requires radiation, anti-CTLA4 and anti-PD-L1/PD-1. Anti-CTLA4 predominantly inhibits T-regulatory cells (Treg cells), thereby increasing the CD8 T-cell to Treg (CD8/Treg) ratio. Radiation enhances the diversity of the T-cell receptor (TCR) repertoire of intratumoral T cells. Together, anti-CTLA4 promotes expansion of T cells, while radiation shapes the TCR repertoire of the expanded peripheral clones. Addition of PD-L1 blockade reverses T-cell exhaustion to mitigate depression in the CD8/Treg ratio and further encourages oligoclonal T-cell expansion. Similarly to results from mice, patients on our clinical trial with melanoma showing high PD-L1 did not respond to radiation plus anti-CTLA4, demonstrated persistent T-cell exhaustion, and rapidly progressed. Thus, PD-L1 on melanoma cells allows tumours to escape anti-CTLA4-based therapy, and the combination of radiation, anti-CTLA4 and anti-PD-L1 promotes response and immunity through distinct mechanisms.
in vivo CD8+ T cell depletion
Coffelt, S. B., et al. (2015). "IL-17-producing gammadelta T cells and neutrophils conspire to promote breast cancer metastasis" Nature 522(7556): 345-348. PubMed
Metastatic disease remains the primary cause of death for patients with breast cancer. The different steps of the metastatic cascade rely on reciprocal interactions between cancer cells and their microenvironment. Within this local microenvironment and in distant organs, immune cells and their mediators are known to facilitate metastasis formation. However, the precise contribution of tumour-induced systemic inflammation to metastasis and the mechanisms regulating systemic inflammation are poorly understood. Here we show that tumours maximize their chance of metastasizing by evoking a systemic inflammatory cascade in mouse models of spontaneous breast cancer metastasis. We mechanistically demonstrate that interleukin (IL)-1beta elicits IL-17 expression from gamma delta (gammadelta) T cells, resulting in systemic, granulocyte colony-stimulating factor (G-CSF)-dependent expansion and polarization of neutrophils in mice bearing mammary tumours. Tumour-induced neutrophils acquire the ability to suppress cytotoxic T lymphocytes carrying the CD8 antigen, which limit the establishment of metastases. Neutralization of IL-17 or G-CSF and absence of gammadelta T cells prevents neutrophil accumulation and downregulates the T-cell-suppressive phenotype of neutrophils. Moreover, the absence of gammadelta T cells or neutrophils profoundly reduces pulmonary and lymph node metastases without influencing primary tumour progression. Our data indicate that targeting this novel cancer-cell-initiated domino effect within the immune system–the gammadelta T cell/IL-17/neutrophil axis–represents a new strategy to inhibit metastatic disease.
in vivo CD8+ T cell depletion
Evans, E. E., et al. (2015). "Antibody Blockade of Semaphorin 4D Promotes Immune Infiltration into Tumor and Enhances Response to Other Immunomodulatory Therapies" Cancer Immunol Res 3(6): 689-701. PubMed
Semaphorin 4D (SEMA4D, CD100) and its receptor plexin-B1 (PLXNB1) are broadly expressed in murine and human tumors, and their expression has been shown to correlate with invasive disease in several human tumors. SEMA4D normally functions to regulate the motility and differentiation of multiple cell types, including those of the immune, vascular, and nervous systems. In the setting of cancer, SEMA4D-PLXNB1 interactions have been reported to affect vascular stabilization and transactivation of ERBB2, but effects on immune-cell trafficking in the tumor microenvironment (TME) have not been investigated. We describe a novel immunomodulatory function of SEMA4D, whereby strong expression of SEMA4D at the invasive margins of actively growing tumors influences the infiltration and distribution of leukocytes in the TME. Antibody neutralization of SEMA4D disrupts this gradient of expression, enhances recruitment of activated monocytes and lymphocytes into the tumor, and shifts the balance of cells and cytokines toward a proinflammatory and antitumor milieu within the TME. This orchestrated change in the tumor architecture was associated with durable tumor rejection in murine Colon26 and ERBB2(+) mammary carcinoma models. The immunomodulatory activity of anti-SEMA4D antibody can be enhanced by combination with other immunotherapies, including immune checkpoint inhibition and chemotherapy. Strikingly, the combination of anti-SEMA4D antibody with antibody to CTLA-4 acts synergistically to promote complete tumor rejection and survival. Inhibition of SEMA4D represents a novel mechanism and therapeutic strategy to promote functional immune infiltration into the TME and inhibit tumor progression.
in vivo CD8+ T cell depletion
Van der Jeught, K., et al. (2014). "Intratumoral administration of mRNA encoding a fusokine consisting of IFN-beta and the ectodomain of the TGF-beta receptor II potentiates antitumor immunity" Oncotarget 5(20): 10100-10113. PubMed
It is generally accepted that the success of immunotherapy depends on the presence of tumor-specific CD8(+) cytotoxic T cells and the modulation of the tumor environment. In this study, we validated mRNA encoding soluble factors as a tool to modulate the tumor microenvironment to potentiate infiltration of tumor-specific T cells. Intratumoral delivery of mRNA encoding a fusion protein consisting of interferon-beta and the ectodomain of the transforming growth factor-beta receptor II, referred to as Fbeta(2), showed therapeutic potential. The treatment efficacy was dependent on CD8(+) T cells and could be improved through blockade of PD-1/PD-L1 interactions. In vitro studies revealed that administration of Fbeta(2) to tumor cells resulted in a reduced proliferation and increased expression of MHC I but also PD-L1. Importantly, Fbeta(2) enhanced the antigen presenting capacity of dendritic cells, whilst reducing the suppressive activity of myeloid-derived suppressor cells. In conclusion, these data suggest that intratumoral delivery of mRNA encoding soluble proteins, such as Fbeta(2), can modulate the tumor microenvironment, leading to effective antitumor T cell responses, which can be further potentiated through combination therapy.
in vivo CD8+ T cell depletion
Deng, L., et al. (2014). "Irradiation and anti-PD-L1 treatment synergistically promote antitumor immunity in mice" J Clin Invest 124(2): 687-695. PubMed
High-dose ionizing irradiation (IR) results in direct tumor cell death and augments tumor-specific immunity, which enhances tumor control both locally and distantly. Unfortunately, local relapses often occur following IR treatment, indicating that IR-induced responses are inadequate to maintain antitumor immunity. Therapeutic blockade of the T cell negative regulator programmed death-ligand 1 (PD-L1, also called B7-H1) can enhance T cell effector function when PD-L1 is expressed in chronically inflamed tissues and tumors. Here, we demonstrate that PD-L1 was upregulated in the tumor microenvironment after IR. Administration of anti-PD-L1 enhanced the efficacy of IR through a cytotoxic T cell-dependent mechanism. Concomitant with IR-mediated tumor regression, we observed that IR and anti-PD-L1 synergistically reduced the local accumulation of tumor-infiltrating myeloid-derived suppressor cells (MDSCs), which suppress T cells and alter the tumor immune microenvironment. Furthermore, activation of cytotoxic T cells with combination therapy mediated the reduction of MDSCs in tumors through the cytotoxic actions of TNF. Our data provide evidence for a close interaction between IR, T cells, and the PD-L1/PD-1 axis and establish a basis for the rational design of combination therapy with immune modulators and radiotherapy.
in vivo CD8+ T cell depletion
DeBerge, M. P., et al. (2014). "Soluble, but not transmembrane, TNF-alpha is required during influenza infection to limit the magnitude of immune responses and the extent of immunopathology" J Immunol 192(12): 5839-5851. PubMed
TNF-alpha is a pleotropic cytokine that has both proinflammatory and anti-inflammatory functions during influenza infection. TNF-alpha is first expressed as a transmembrane protein that is proteolytically processed to release a soluble form. Transmembrane TNF-alpha (memTNF-alpha) and soluble TNF-alpha (solTNF-alpha) have been shown to exert distinct tissue-protective or tissue-pathologic effects in several disease models. However, the relative contributions of memTNF-alpha or solTNF-alpha in regulating pulmonary immunopathology following influenza infection are unclear. Therefore, we performed intranasal influenza infection in mice exclusively expressing noncleavable memTNF-alpha or lacking TNF-alpha entirely and examined the outcomes. We found that solTNF-alpha, but not memTNF-alpha, was required to limit the size of the immune response and the extent of injury. In the absence of solTNF-alpha, there was a significant increase in the CD8(+) T cell response, including virus-specific CD8(+) T cells, which was due in part to an increased resistance to activation-induced cell death. We found that solTNF-alpha mediates these immunoregulatory effects primarily through TNFR1, because mice deficient in TNFR1, but not TNFR2, exhibited dysregulated immune responses and exacerbated injury similar to that observed in mice lacking solTNF-alpha. We also found that solTNF-alpha expression was required early during infection to regulate the magnitude of the CD8(+) T cell response, indicating that early inflammatory events are critical for the regulation of the effector phase. Taken together, these findings suggest that processing of memTNF-alpha to release solTNF-alpha is a critical event regulating the immune response during influenza infection.
in vivo CD8+ T cell depletion
Vegran, F., et al. (2014). "The transcription factor IRF1 dictates the IL-21-dependent anticancer functions of TH9 cells" Nat Immunol 15(8): 758-766. PubMed
The TH9 subset of helper T cells was initially shown to contribute to the induction of autoimmune and allergic diseases, but subsequent evidence has suggested that these cells also exert antitumor activities. However, the molecular events that account for their effector properties are elusive. Here we found that the transcription factor IRF1 enhanced the effector function of TH9 cells and dictated their anticancer properties. Under TH9-skewing conditions, interleukin 1beta (IL-1beta) induced phosphorylation of the transcription factor STAT1 and subsequent expression of IRF1, which bound to the promoters of Il9 and Il21 and enhanced secretion of the cytokines IL-9 and IL-21 from TH9 cells. Furthermore, IL-1beta-induced TH9 cells exerted potent anticancer functions in an IRF1- and IL-21-dependent manner. Our findings thus identify IRF1 as a target for controlling the function of TH9 cells.
in vivo CD8+ T cell depletion
Sandoval, F., et al. (2013). "Mucosal imprinting of vaccine-induced CD8(+) T cells is crucial to inhibit the growth of mucosal tumors" Sci Transl Med 5(172): 172ra120. PubMed
Although many human cancers are located in mucosal sites, most cancer vaccines are tested against subcutaneous tumors in preclinical models. We therefore wondered whether mucosa-specific homing instructions to the immune system might influence mucosal tumor outgrowth. We showed that the growth of orthotopic head and neck or lung cancers was inhibited when a cancer vaccine was delivered by the intranasal mucosal route but not the intramuscular route. This antitumor effect was dependent on CD8(+) T cells. Indeed, only intranasal vaccination elicited mucosal-specific CD8(+) T cells expressing the mucosal integrin CD49a. Blockade of CD49a decreased intratumoral CD8(+) T cell infiltration and the efficacy of cancer vaccine on mucosal tumor. We then showed that after intranasal vaccination, dendritic cells from lung parenchyma, but not those from spleen, induced the expression of CD49a on cocultured specific CD8(+) T cells. Tumor-infiltrating lymphocytes from human mucosal lung cancer also expressed CD49a, which supports the relevance and possible extrapolation of these results in humans. We thus identified a link between the route of vaccination and the induction of a mucosal homing program on induced CD8(+) T cells that controlled their trafficking. Immunization route directly affected the efficacy of the cancer vaccine to control mucosal tumors.
in vivo CD8+ T cell depletion
Kearl, T. J., et al. (2013). "Programmed death receptor-1/programmed death receptor ligand-1 blockade after transient lymphodepletion to treat myeloma" J Immunol 190(11): 5620-5628. PubMed
Early phase clinical trials targeting the programmed death receptor-1/ligand-1 (PD-1/PD-L1) pathway to overcome tumor-mediated immunosuppression have reported promising results for a variety of cancers. This pathway appears to play an important role in the failure of immune reactivity to malignant plasma cells in multiple myeloma patients, as the tumor cells express relatively high levels of PD-L1, and T cells show increased PD-1 expression. In the current study, we demonstrate that PD-1/PD-L1 blockade with a PD-L1-specific Ab elicits rejection of a murine myeloma when combined with lymphodepleting irradiation. This particular combined approach by itself has not previously been shown to be efficacious in other tumor models. The antitumor effect of lymphodepletion/anti-PD-L1 therapy was most robust when tumor Ag-experienced T cells were present either through cell transfer or survival after nonmyeloablative irradiation. In vivo depletion of CD4 or CD8 T cells completely eliminated antitumor efficacy of the lymphodepletion/anti-PD-L1 therapy, indicating that both T cell subsets are necessary for tumor rejection. Elimination of myeloma by T cells occurs relatively quickly as tumor cells in the bone marrow were nearly nondetectable by 5 d after the first anti-PD-L1 treatment, suggesting that antimyeloma reactivity is primarily mediated by preactivated T cells, rather than newly generated myeloma-reactive T cells. Anti-PD-L1 plus lymphodepletion failed to improve survival in two solid tumor models, but demonstrated significant efficacy in two hematologic malignancy models. In summary, our results support the clinical testing of lymphodepletion and PD-1/PD-L1 blockade as a novel approach for improving the survival of patients with multiple myeloma.
in vivo CD8+ T cell depletion
Pasche, N., et al. (2012). "The antibody-based delivery of interleukin-12 to the tumor neovasculature eradicates murine models of cancer in combination with paclitaxel" Clin Cancer Res 18(15): 4092-4103. PubMed
PURPOSE: Interleukin-12 (IL12) is a potent proinflammatory cytokine with antitumor activity. Its heterodimeric nature makes it compatible with a large variety of different immunocytokine formats. Here we report the design, production, and characterization of a novel immunocytokine, based on the fusion of the F8 antibody (specific to the alternatively spliced EDA domain of fibronectin, a marker of tumor neovasculature) with IL12 (termed IL12-F8-F8). EXPERIMENTAL DESIGN: We developed a novel immunocytokine based on the sequential fusion of interleukin-12 as a single polypeptide with two F8 antibodies in single-chain Fv (scFv) format. The fusion protein was characterized in vitro, and its targeting performance was assessed in vivo. The immunocytokine antitumor activity was studied as monotherapy as well as in combination therapies in three different murine tumor models. Moreover, depletion experiments and tumor analysis revealed a dominant role of natural killer cells for the mechanism of action. RESULTS: IL12-F8-F8 can be produced in mammalian cells, yielding a product of good pharmaceutical quality, capable of selective localization on the tumor neovasculature in vivo, as judged by quantitative biodistribution analysis with radioiodinated protein preparations. The protein potently inhibited tumor growth in three different immunocompetent syngeneic models of cancer. The treatment was generally well tolerated. Moreover, the IL12-F8-F8 fusion protein could be produced both with murine IL12 (mIL12) and with human IL12 (hIL12). CONCLUSIONS: The potent antitumor activity of mIL12-F8-F8, studied alone or in combination with paclitaxel in different tumor models, paves the way to the clinical development of the fully human immunocytokine.
in vivo CD8+ T cell depletion
Quezada, S. A., et al. (2010). "Tumor-reactive CD4(+) T cells develop cytotoxic activity and eradicate large established melanoma after transfer into lymphopenic hosts" J Exp Med 207(3): 637-650. PubMed
Adoptive transfer of large numbers of tumor-reactive CD8(+) cytotoxic T lymphocytes (CTLs) expanded and differentiated in vitro has shown promising clinical activity against cancer. However, such protocols are complicated by extensive ex vivo manipulations of tumor-reactive cells and have largely focused on CD8(+) CTLs, with much less emphasis on the role and contribution of CD4(+) T cells. Using a mouse model of advanced melanoma, we found that transfer of small numbers of naive tumor-reactive CD4(+) T cells into lymphopenic recipients induces substantial T cell expansion, differentiation, and regression of large established tumors without the need for in vitro manipulation. Surprisingly, CD4(+) T cells developed cytotoxic activity, and tumor rejection was dependent on class II-restricted recognition of tumors by tumor-reactive CD4(+) T cells. Furthermore, blockade of the coinhibitory receptor CTL-associated antigen 4 (CTLA-4) on the transferred CD4(+) T cells resulted in greater expansion of effector T cells, diminished accumulation of tumor-reactive regulatory T cells, and superior antitumor activity capable of inducing regression of spontaneous mouse melanoma. These findings suggest a novel potential therapeutic role for cytotoxic CD4(+) T cells and CTLA-4 blockade in cancer immunotherapy, and demonstrate the potential advantages of differentiating tumor-reactive CD4(+) cells in vivo over current protocols favoring in vitro expansion and differentiation.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
CD276-dependent efferocytosis by tumor-associated macrophages promotes immune evasion in bladder cancer.
In Nature Communications on 1 April 2024 by Cheng, M., Chen, S., et al.
PubMed
Interplay between innate and adaptive immune cells is important for the antitumor immune response. However, the tumor microenvironment may turn immune suppressive, and tumor associated macrophages are playing a role in this transition. Here, we show that CD276, expressed on tumor-associated macrophages (TAM), play a role in diminishing the immune response against tumors. Using a model of tumors induced by N-butyl-N-(4-hydroxybutyl) nitrosamine in BLCA male mice we show that genetic ablation of CD276 in TAMs blocks efferocytosis and enhances the expression of the major histocompatibility complex class II (MHCII) of TAMs. This in turn increases CD4 + and cytotoxic CD8 + T cell infiltration of the tumor. Combined single cell RNA sequencing and functional experiments reveal that CD276 activates the lysosomal signaling pathway and the transcription factor JUN to regulate the expression of AXL and MerTK, resulting in enhanced efferocytosis in TAMs. Proving the principle, we show that simultaneous blockade of CD276 and PD-1 restrain tumor growth better than any of the components as a single intervention. Taken together, our study supports a role for CD276 in efferocytosis by TAMs, which is potentially targetable for combination immune therapy. © 2024. The Author(s).
- Cancer Research,
- Immunology and Microbiology,
- Genetics
Genetic fusion of CCL11 to antigens enhances antigenicity in nucleic acid vaccines and eradicates tumor mass through optimizing T-cell response.
In Molecular Cancer on 8 March 2024 by Qi, H., Sun, Z., et al.
PubMed
Nucleic acid vaccines have shown promising potency and efficacy for cancer treatment with robust and specific T-cell responses. Improving the immunogenicity of delivered antigens helps to extend therapeutic efficacy and reduce dose-dependent toxicity. Here, we systematically evaluated chemokine-fused HPV16 E6/E7 antigen to improve the cellular and humoral immune responses induced by nucleotide vaccines in vivo. We found that fusion with different chemokines shifted the nature of the immune response against the antigens. Although a number of chemokines were able to amplify specific CD8 + T-cell or humoral response alone or simultaneously. CCL11 was identified as the most potent chemokine in improving immunogenicity, promoting specific CD8 + T-cell stemness and generating tumor rejection. Fusing CCL11 with E6/E7 antigen as a therapeutic DNA vaccine significantly improved treatment effectiveness and caused eradication of established large tumors in 92% tumor-bearing mice (n = 25). Fusion antigens with CCL11 expanded the TCR diversity of specific T cells and induced the infiltration of activated specific T cells, neutrophils, macrophages and dendritic cells (DCs) into the tumor, which created a comprehensive immune microenvironment lethal to tumor. Combination of the DNA vaccine with anti-CTLA4 treatment further enhanced the therapeutic effect. In addition, CCL11 could also be used for mRNA vaccine design. To summarize, CCL11 might be a potent T cell enhancer against cancer. © 2024. The Author(s).
- Mus musculus (House mouse),
- Immunology and Microbiology,
- COVID-19
A T cell-based SARS-CoV-2 spike protein vaccine provides protection without antibodies.
In JCI Insight on 8 March 2024 by Shi, J., Zheng, J., et al.
PubMed
SARS-CoV-2 spike-based vaccines are used to control the COVID-19 pandemic. However, emerging variants have become resistant to antibody neutralization and further mutations may lead to full resistance. We tested whether T cells alone could provide protection without antibodies. We designed a T cell-based vaccine in which SARS-CoV-2 spike sequences were rearranged and attached to ubiquitin. Immunization of mice with the vaccine induced no specific antibodies, but strong specific T cell responses. We challenged mice with SARS-CoV-2 wild-type strain or an Omicron variant after the immunization and monitored survival or viral titers in the lungs. The mice were significantly protected against death and weight loss caused by the SARS-CoV-2 wild-type strain, and the viral titers in the lungs of mice challenged with the SARS-CoV-2 wild-type strain or the Omicron variant were significantly reduced. Importantly, depletion of CD4+ or CD8+ T cells led to significant loss of the protection. Our analyses of spike protein sequences of the variants indicated that fewer than one-third presented by dominant HLA alleles were mutated and that most of the mutated epitopes were in the subunit 1 region. As the subunit 2 region is conservative, the vaccines targeting spike protein are expected to protect against future variants due to the T cell responses.
- Cancer Research
A novel antagonist of the CCL5/CCR5 axis suppresses the tumor growth and metastasis of triple-negative breast cancer by CCR5-YAP1 regulation
Preprint on BioRxiv : the Preprint Server for Biology on 17 November 2023 by Chen, L., Xu, G., et al.
PubMed
Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer (BC) with a high mortality rate, and few effective therapeutic strategies are available. CCL5/CCR5 is an appealing immunotherapeutic target for TNBC. However, its signaling mechanism is poorly understood and its direct antagonists have not been reported. Here, we developed a high-throughput screening (HTS) assay for discovering its antagonists. Verteporfin was identified as a more selective and potent antagonist than the known CCR5 antagonist maraviroc. Without photodynamic therapy, verteporfin demonstrated significant inhibition on TNBC tumor growth through immune regulation, remarkable suppression of lung metastasis by cell-intrinsic mechanism, and a significant extension of overall survival in vivo . Mechanistically, CCR5 was found to be essential for expression of the key hippo effector YAP1. It promoted YAP1 transcription via HIF-1α and exerted further control over the migration of CD8 + T, NK, and MDSC immune cells through chemokines CXCL16 and CXCL8 which were identified from RNA-seq. Moreover, the CCR5-YAP1 axis played a vital role in promoting metastasis by modulating β-catenin and core epithelial-mesenchymal transition transcription factors ZEB1 and ZEB2. It is noteworthy that the regulatory relationship between CCR5 and YAP1 was observed across various BC subtypes, TNBC patients, and showed potential relevance in fifteen additional cancer types. Overall, this study introduced an easy-to-use HTS assay that streamlines the discovery of CCL5/CCR5 axis antagonists. Verteporfin was identified as a specific molecular probe of this axis with great potentials as a therapeutic agent for treating sixteen malignant diseases characterized by heightened CCR5 and YAP1 levels.
- Cancer Research
Galectin-1 Mediates Chronic STING Activation in Tumors to Promote Metastasis through MDSC Recruitment.
In Cancer Research on 2 October 2023 by Nambiar, D. K., Viswanathan, V., et al.
PubMed
The immune system plays a crucial role in the regulation of metastasis. Tumor cells systemically change immune functions to facilitate metastatic progression. Through this study, we deciphered how tumoral galectin-1 (Gal1) expression shapes the systemic immune environment to promote metastasis in head and neck cancer (HNC). In multiple preclinical models of HNC and lung cancer in immunogenic mice, Gal1 fostered the establishment of a premetastatic niche through polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC), which altered the local microenvironment to support metastatic spread. RNA sequencing of MDSCs from premetastatic lungs in these models demonstrated the role of PMN-MDSCs in collagen and extracellular matrix remodeling in the premetastatic compartment. Gal1 promoted MDSC accumulation in the premetastatic niche through the NF-κB signaling axis, triggering enhanced CXCL2-mediated MDSC migration. Mechanistically, Gal1 sustained NF-κB activation in tumor cells by enhancing stimulator of interferon gene (STING) protein stability, leading to prolonged inflammation-driven MDSC expansion. These findings suggest an unexpected protumoral role of STING activation in metastatic progression and establish Gal1 as an endogenous-positive regulator of STING in advanced-stage cancers. Galectin-1 increases STING stability in cancer cells that activates NF-κB signaling and CXCL2 expression to promote MDSC trafficking, which stimulates the generation of a premetastatic niche and facilitates metastatic progression. ©2023 American Association for Cancer Research.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
Dual Blockade of EP2 and EP4 Signaling is Required for Optimal Immune Activation and Antitumor Activity Against Prostaglandin-Expressing Tumors.
In Cancer Res Commun on 1 August 2023 by Francica, B. J., Holtz, A., et al.
PubMed
While the role of prostaglandin E2 (PGE2) in promoting malignant progression is well established, how to optimally block the activity of PGE2 signaling remains to be demonstrated. Clinical trials with prostaglandin pathway targeted agents have shown activity but without sufficient significance or dose-limiting toxicities that have prevented approval. PGE2 signals through four receptors (EP1-4) to modulate tumor progression. EP2 and EP4 signaling exacerbates tumor pathology and is immunosuppressive through potentiating cAMP production. EP1 and EP3 signaling has the opposite effect through increasing IP3 and decreasing cAMP. Using available small-molecule antagonists of single EP receptors, the cyclooxygenase-2 (COX-2) inhibitor celecoxib, or a novel dual EP2/EP4 antagonist generated in this investigation, we tested which approach to block PGE2 signaling optimally restored immunologic activity in mouse and human immune cells and antitumor activity in syngeneic, spontaneous, and xenograft tumor models. We found that dual antagonism of EP2 and EP4 together significantly enhanced the activation of PGE2-suppressed mouse and human monocytes and CD8+ T cells in vitro as compared with single EP antagonists. CD8+ T-cell activation was dampened by single EP1 and EP3 antagonists. Dual EP2/EP4 PGE2 receptor antagonists increased tumor microenvironment lymphocyte infiltration and significantly reduced disease burden in multiple tumor models, including in the adenomatous polyposis coli (APC)min+/- spontaneous colorectal tumor model, compared with celecoxib. These results support a hypothesis that redundancy of EP2 and EP4 receptor signaling necessitates a therapeutic strategy of dual blockade of EP2 and EP4. Here we describe TPST-1495, a first-in-class orally available small-molecule dual EP2/EP4 antagonist. Prostaglandin (PGE2) drives tumor progression but the pathway has not been effectively drugged. We demonstrate significantly enhanced immunologic potency and antitumor activity through blockade of EP2 and EP4 PGE2 receptor signaling together with a single molecule. © 2023 The Authors; Published by the American Association for Cancer Research.
- Cancer Research,
- Mus musculus (House mouse)
Overcoming cancer-associated fibroblast-induced immunosuppression by anti-interleukin-6 receptor antibody.
In Cancer Immunology, Immunotherapy : CII on 1 July 2023 by Nishiwaki, N., Noma, K., et al.
PubMed
Cancer-associated fibroblasts (CAFs) are a critical component of the tumor microenvironment and play a central role in tumor progression. Previously, we reported that CAFs might induce tumor immunosuppression via interleukin-6 (IL-6) and promote tumor progression by blocking local IL-6 in the tumor microenvironment with neutralizing antibody. Here, we explore whether an anti-IL-6 receptor antibody could be used as systemic therapy to treat cancer, and further investigate the mechanisms by which IL-6 induces tumor immunosuppression. In clinical samples, IL-6 expression was significantly correlated with α-smooth muscle actin expression, and high IL-6 cases showed tumor immunosuppression. Multivariate analysis showed that IL-6 expression was an independent prognostic factor. In vitro, IL-6 contributed to cell proliferation and differentiation into CAFs. Moreover, IL-6 increased hypoxia-inducible factor 1α (HIF1α) expression and induced tumor immunosuppression by enhancing glucose uptake by cancer cells and competing for glucose with immune cells. MR16-1, a rodent analog of anti-IL-6 receptor antibody, overcame CAF-induced immunosuppression and suppressed tumor progression in immunocompetent murine cancer models by regulating HIF1α activation in vivo. The anti-IL-6 receptor antibody could be systemically employed to overcome tumor immunosuppression and improve patient survival with various cancers. Furthermore, the tumor immunosuppression was suggested to be induced by IL-6 via HIF1α activation. © 2023. The Author(s).
- Cancer Research
Gas therapy potentiates aggregation-induced emission luminogen-based photoimmunotherapy of poorly immunogenic tumors through cGAS-STING pathway activation.
In Nature Communications on 23 May 2023 by Wang, K., Li, Y., et al.
PubMed
The immunologically "cold" microenvironment of triple negative breast cancer results in resistance to current immunotherapy. Here, we reveal the immunoadjuvant property of gas therapy with cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway activation to augment aggregation-induced emission (AIE)-active luminogen (AIEgen)-based photoimmunotherapy. A virus-mimicking hollow mesoporous tetrasulfide-doped organosilica is developed for co-encapsulation of AIEgen and manganese carbonyl to fabricate gas nanoadjuvant. As tetra-sulfide bonds are responsive to intratumoral glutathione, the gas nanoadjuvant achieves tumor-specific drug release, promotes photodynamic therapy, and produces hydrogen sulfide (H2S). Upon near-infrared laser irradiation, the AIEgen-mediated phototherapy triggers the burst of carbon monoxide (CO)/Mn2+. Both H2S and CO can destroy mitochondrial integrity to induce leakage of mitochondrial DNA into the cytoplasm, serving as gas immunoadjuvants to activate cGAS-STING pathway. Meanwhile, Mn2+ can sensitize cGAS to augment STING-mediated type I interferon production. Consequently, the gas nanoadjuvant potentiates photoimmunotherapy of poorly immunogenic breast tumors in female mice. © 2023. The Author(s).
- Cancer Research,
- Cell Biology
Engineered bacterial outer membrane vesicles encapsulating oncolytic adenoviruses enhance the efficacy of cancer virotherapy by augmenting tumor cell autophagy.
In Nature Communications on 22 May 2023 by Ban, W., Sun, M., et al.
PubMed
Oncolytic adenovirus (Ad) infection promotes intracellular autophagy in tumors. This could kill cancer cells and contribute to Ads-mediated anticancer immunity. However, the low intratumoral content of intravenously delivered Ads could be insufficient to efficiently activate tumor over-autophagy. Herein, we report bacterial outer membrane vesicles (OMVs)-encapsulating Ads as microbial nanocomposites that are engineered for autophagy-cascade-augmented immunotherapy. Biomineral shells cover the surface antigens of OMVs to slow their clearance during in vivo circulation, enhancing intratumoral accumulation. After entering tumor cells, there is excessive H2O2 accumulation through the catalytic effect of overexpressed pyranose oxidase (P2O) from microbial nanocomposite. This increases oxidative stress levels and triggers tumor autophagy. The autophagy-induced autophagosomes further promote Ads replication in infected tumor cells, leading to Ads-overactivated autophagy. Moreover, OMVs are powerful immunostimulants for remolding the immunosuppressive tumor microenvironment, facilitating antitumor immune response in preclinical cancer models in female mice. Therefore, the present autophagy-cascade-boosted immunotherapeutic method can expand OVs-based immunotherapy. © 2023. The Author(s).
- Neuroscience,
- Immunology and Microbiology
Microglia-mediated T cell infiltration drives neurodegeneration in tauopathy.
In Nature on 1 March 2023 by Chen, X., Firulyova, M., et al.
PubMed
Extracellular deposition of amyloid-β as neuritic plaques and intracellular accumulation of hyperphosphorylated, aggregated tau as neurofibrillary tangles are two of the characteristic hallmarks of Alzheimer's disease1,2. The regional progression of brain atrophy in Alzheimer's disease highly correlates with tau accumulation but not amyloid deposition3-5, and the mechanisms of tau-mediated neurodegeneration remain elusive. Innate immune responses represent a common pathway for the initiation and progression of some neurodegenerative diseases. So far, little is known about the extent or role of the adaptive immune response and its interaction with the innate immune response in the presence of amyloid-β or tau pathology6. Here we systematically compared the immunological milieux in the brain of mice with amyloid deposition or tau aggregation and neurodegeneration. We found that mice with tauopathy but not those with amyloid deposition developed a unique innate and adaptive immune response and that depletion of microglia or T cells blocked tau-mediated neurodegeneration. Numbers of T cells, especially those of cytotoxic T cells, were markedly increased in areas with tau pathology in mice with tauopathy and in the Alzheimer's disease brain. T cell numbers correlated with the extent of neuronal loss, and the cells dynamically transformed their cellular characteristics from activated to exhausted states along with unique TCR clonal expansion. Inhibition of interferon-γ and PDCD1 signalling both significantly ameliorated brain atrophy. Our results thus reveal a tauopathy- and neurodegeneration-related immune hub involving activated microglia and T cell responses, which could serve as therapeutic targets for preventing neurodegeneration in Alzheimer's disease and primary tauopathies. © 2023. The Author(s), under exclusive licence to Springer Nature Limited.
- Cancer Research,
- Cell Biology,
- Immunology and Microbiology,
- Mus musculus (House mouse)
Targeting ubiquitin-specific protease 8 sensitizes anti-programmed death-ligand 1 immunotherapy of pancreatic cancer.
In Cell Death and Differentiation on 1 February 2023 by Yang, H., Zhang, X., et al.
PubMed
Programmed death-1 (PD-1) and its ligand programmed death-ligand 1 (PD-L1) help tumor cells evade immune surveillance, and are regarded as important targets of anti-tumor immunotherapy. Post-translational modification of PD-L1 has potential value in immunosuppression. Here, we identified that ubiquitin-specific protease 8 (USP8) deubiquitinates PD-L1. Pancreatic cancer tissues exhibited significantly increased USP8 levels compared with those in normal tissues. Clinically, the expression of USP8 showed a significant association with the tumor-node-metastasis stage in multiple patient-derived cohorts of pancreatic cancer. Meanwhile, USP8 deficiency could reduce tumor invasion and migration and tumor size in an immunity-dependent manner, and improve anti-tumor immunogenicity. USP8 inhibitor pretreatment led to reduced tumorigenesis and immunocompetent mice with Usp8 knockdown tumors exhibited extended survival. Moreover, USP8 interacted positively with PD-L1 and upregulated its expression by inhibiting the ubiquitination-regulated proteasome degradation pathway in pancreatic cancer. Combination therapy with a USP8 inhibitor and anti-PD-L1 effectively suppressed pancreatic tumor growth by activation of cytotoxic T-cells and the anti-tumor immunity was mainly dependent on the PD-L1 pathway and CD8 + T cells. Our findings highlight the importance of targeting USP8, which can sensitize PD-L1-targeted pancreatic cancer to immunotherapy and might represent a novel therapeutic strategy to treat patients with pancreatic tumors in the future. © 2022. The Author(s).
- Cancer Research,
- Immunology and Microbiology,
- Mus musculus (House mouse)
Cancer-targeted photoimmunotherapy induces antitumor immunity and can be augmented by anti-PD-1 therapy for durable anticancer responses in an immunologically active murine tumor model.
In Cancer Immunology, Immunotherapy : CII on 1 January 2023 by Hsu, M. A., Okamura, S. M., et al.
PubMed
The complex immunosuppressive nature of solid tumor microenvironments poses a significant challenge to generating efficacious and durable anticancer responses. Photoimmunotherapy is a cancer treatment strategy by which an antibody is conjugated with a non-toxic light-activatable dye. Following administration of the conjugate and binding to the target tumor, subsequent local laser illumination activates the dye, resulting in highly specific target cell membrane disruption. Here we demonstrate that photoimmunotherapy treatment elicited tumor necrosis, thus inducing immunogenic cell death characterized by the release of damage-associated molecular patterns (DAMPs). Photoimmunotherapy-killed tumor cells activated dendritic cells (DC), leading to the production of proinflammatory cytokines, T cell stimulation, priming antigen-specific T cells, and durable memory T cell responses, which led complete responder mice to effectively reject new tumors upon rechallenge. PD-1 blockade in combination with photoimmunotherapy enhanced overall anticancer efficacy, including against anti-PD-1-resistant tumors. The combination treatment also elicited abscopal anticancer activity, as observed by reduction of distal, non-illuminated tumors, further demonstrating the ability of photoimmunotherapy to harness local and peripheral T cell responses. With this work we therefore delineate the immune mechanisms of action for photoimmunotherapy and demonstrate the potential for cancer-targeted photoimmunotherapy to be combined with other immunotherapy approaches for augmented, durable anticancer efficacy. Moreover, we demonstrate responses utilizing various immunocompetent mouse models, as well as in vitro data from human cells, suggesting broad translational potential. © 2022. The Author(s).
- Cancer Research,
- Immunology and Microbiology
Induction of T-helper-17-cell-mediated anti-tumour immunity by pathogen-mimicking polymer nanoparticles.
In Nature Biomedical Engineering on 1 January 2023 by Son, S., Nam, J., et al.
PubMed
The effectivity of cancer immunotherapies is hindered by immunosuppressive tumour microenvironments that are poorly infiltrated by effector T cells and natural killer cells. In infection and autoimmune disease, the recruitment and activation of effector immune cells is coordinated by pro-inflammatory T helper 17 (TH17) cells. Here we show that pathogen-mimicking hollow nanoparticles displaying mannan (a polysaccharide that activates TH17 cells in microbial cell walls) limit the fraction of regulatory T cells and induce TH17-cell-mediated anti-tumour responses. The nanoparticles activate the pattern-recognition receptor Dectin-2 and Toll-like receptor 4 in dendritic cells, and promote the differentiation of CD4+ T cells into the TH17 phenotype. In mice, intra-tumoural administration of the nanoparticles decreased the fraction of regulatory T cells in the tumour while markedly increasing the fractions of TH17 cells (and the levels of TH17-cell-associated cytokines), CD8+ T cells, natural killer cells and M1-like macrophages. The anti-tumoural activity of the effector cells was amplified by an agonistic antibody against the co-stimulatory receptor OX40 in multiple mouse models. Nanomaterials that induce TH17-cell-mediated immune responses may have therapeutic potential. © 2022. The Author(s), under exclusive licence to Springer Nature Limited.
- Cancer Research,
- Immunology and Microbiology,
- Mus musculus (House mouse)
Tumor-specific CD4 T cells instruct monocyte differentiation in pancreatic ductal adenocarcinoma
Preprint on BioRxiv : the Preprint Server for Biology on 10 November 2022 by Patterson, M. T., Burrack, A. L., et al.
PubMed
Summary Pancreatic ductal adenocarcinoma (PDA) is a lethal malignancy resistant to immunotherapy. The pancreatic tumor microenvironment is shaped and maintained by myeloid cells that outnumber tumor cells. Here, using monocyte fate-mapping PDA mouse models and human tumor tissues, we identify monocytes give rise to most heterogeneous macrophage subpopulations in PDA. We show that monocyte differentiation is governed by the local presence of CD4, but not CD8, T cells. We demonstrate that tumor specific CD4 T cells induce monocyte differentiation into antitumor MHCII hi proinflammatory macrophages dependent on non-redundant IFNγ and CD40 signaling pathways that suppress tumor growth. Pancreatic tissue-resident macrophages exhibit an immunosuppressive pro-tumor state that is refractory to the modulatory effects of antitumor CD4 T cells. Intratumoral monocytes adopt a pro-tumor fate indistinguishable from tissue-resident macrophages following CD4 T cell depletion. Thus, tumor-specific CD4 T cell governance of monocyte fate promotes immune-mediated control of solid tumors. Highlights ▪ Circulating monocytes are progenitors to most heterogeneous macrophage subsets in PDA ▪ Monocyte-derived macrophage acquisition of an MHCII hi phenotype is dependent on tumor-specific CD4 T cells ▪ In the absence of CD4 T cells, monocyte-derived macrophages acquire tissue resident macrophage traits and tumors rapidly progress ▪ IFNγ and CD40 signaling are nonredundant and critical determinants of intratumoral monocyte fate
- Cancer Research,
- Neuroscience,
- Mus musculus (House mouse)
Nociceptor neurons affect cancer immunosurveillance.
In Nature on 1 November 2022 by Balood, M., Ahmadi, M., et al.
PubMed
Solid tumours are innervated by nerve fibres that arise from the autonomic and sensory peripheral nervous systems1-5. Whether the neo-innervation of tumours by pain-initiating sensory neurons affects cancer immunosurveillance remains unclear. Here we show that melanoma cells interact with nociceptor neurons, leading to increases in their neurite outgrowth, responsiveness to noxious ligands and neuropeptide release. Calcitonin gene-related peptide (CGRP)-one such nociceptor-produced neuropeptide-directly increases the exhaustion of cytotoxic CD8+ T cells, which limits their capacity to eliminate melanoma. Genetic ablation of the TRPV1 lineage, local pharmacological silencing of nociceptors and antagonism of the CGRP receptor RAMP1 all reduced the exhaustion of tumour-infiltrating leukocytes and decreased the growth of tumours, nearly tripling the survival rate of mice that were inoculated with B16F10 melanoma cells. Conversely, CD8+ T cell exhaustion was rescued in sensory-neuron-depleted mice that were treated with local recombinant CGRP. As compared with wild-type CD8+ T cells, Ramp1-/- CD8+ T cells were protected against exhaustion when co-transplanted into tumour-bearing Rag1-deficient mice. Single-cell RNA sequencing of biopsies from patients with melanoma revealed that intratumoral RAMP1-expressing CD8+ T cells were more exhausted than their RAMP1-negative counterparts, whereas overexpression of RAMP1 correlated with a poorer clinical prognosis. Overall, our results suggest that reducing the release of CGRP from tumour-innervating nociceptors could be a strategy to improve anti-tumour immunity by eliminating the immunomodulatory effects of CGRP on cytotoxic CD8+ T cells. © 2022. The Author(s).
- In Vivo,
- Mus musculus (House mouse),
- Biochemistry and Molecular biology,
- Cancer Research,
- Immunology and Microbiology
WNK3 inhibition elicits antitumor immunity by suppressing PD-L1 expression on tumor cells and activating T-cell function.
In Experimental & Molecular Medicine on 1 November 2022 by Yoon, H. J., Kim, G. C., et al.
PubMed
Immune checkpoint therapies, such as programmed cell death ligand 1 (PD-L1) blockade, have shown remarkable clinical benefit in many cancers by restoring the function of exhausted T cells. Hence, the identification of novel PD-L1 regulators and the development of their inhibition strategies have significant therapeutic advantages. Here, we conducted pooled shRNA screening to identify regulators of membrane PD-L1 levels in lung cancer cells targeting druggable genes and cancer drivers. We identified WNK lysine deficient protein kinase 3 (WNK3) as a novel positive regulator of PD-L1 expression. The kinase-dead WNK3 mutant failed to elevate PD-L1 levels, indicating the involvement of its kinase domain in this function. WNK3 perturbation increased cancer cell death in cancer cell-immune cell coculture conditions and boosted the secretion of cytokines and cytolytic enzymes, promoting antitumor activities in CD4+ and CD8+ T cells. WNK463, a pan-WNK inhibitor, enhanced CD8+ T-cell-mediated antitumor activity and suppressed tumor growth as a monotherapy as well as in combination with a low-dose anti-PD-1 antibody in the MC38 syngeneic mouse model. Furthermore, we demonstrated that the c-JUN N-terminal kinase (JNK)/c-JUN pathway underlies WNK3-mediated transcriptional regulation of PD-L1. Our findings highlight that WNK3 inhibition might serve as a potential therapeutic strategy for cancer immunotherapy through its concurrent impact on cancer cells and immune cells. © 2022. The Author(s).
- Cancer Research,
- Immunology and Microbiology
IFI16-dependent STING signaling is a crucial regulator of anti-HER2 immune response in HER2+ breast cancer.
In Proceedings of the National Academy of Sciences of the United States of America on 2 August 2022 by Ong, L. T., Lee, W. C., et al.
PubMed
Relapse to anti-HER2 monoclonal antibody (mAb) therapies, such as trastuzumab in HER2+ breast cancer (BC), is associated with residual disease progression due to resistance to therapy. Here, we identify interferon-γ inducible protein 16 (IFI16)-dependent STING signaling as a significant determinant of trastuzumab responses in HER2+ BC. We show that down-regulation of immune-regulated genes (IRG) is specifically associated with poor survival of HER2+, but not other BC subtypes. Among IRG, IFI16 is identified as a direct target of EZH2, the underexpression of which leads to deficient STING activation and downstream CXCL10/11 expression in response to trastuzumab treatment. Dual inhibition of EZH2 and histone deacetylase (HDAC) significantly activates IFI16-dependent immune responses to trastuzumab. Notably, a combination of a novel histone methylation inhibitor with an HDAC inhibitor induces complete tumor eradication and long-term T cell memory in a HER2+ BC mouse model. Our findings demonstrate an epigenetic regulatory mechanism suppressing the expression of the IFI16-CXCL10/11 signaling pathway that provides a survival advantage to HER2+ BC to confer resistance to trastuzumab treatment.
- In Vivo,
- Mus musculus (House mouse)
Ursodeoxycholic acid reduces antitumor immunosuppression by inducing CHIP-mediated TGF-β degradation.
In Nature Communications on 14 June 2022 by Shen, Y., Lu, C., et al.
PubMed
TGF-β is essential for inducing systemic tumor immunosuppression; thus, blocking TGF-β can greatly enhance antitumor immunity. However, there are still no effective TGF-β inhibitors in clinical use. Here, we show that the clinically approved compound ursodeoxycholic acid (UDCA), by degrading TGF-β, enhances antitumor immunity through restraining Treg cell differentiation and activation in tumor-bearing mice. Furthermore, UDCA synergizes with anti-PD-1 to enhance antitumor immunity and tumor-specific immune memory in tumor-bearing mice. UDCA phosphorylates TGF-β at T282 site via TGR5-cAMP-PKA axis, causing increased binding of TGF-β to carboxyl terminus of Hsc70-interacting protein (CHIP). Then, CHIP ubiquitinates TGF-β at the K315 site, initiating p62-dependent autophagic sorting and subsequent degradation of TGF-β. Notably, results of retrospective analysis shows that combination therapy with anti-PD-1 or anti-PD-L1 and UDCA has better efficacy in tumor patients than anti-PD-1 or anti-PD-L1 alone. Thus, our results show a mechanism for TGF-β regulation and implicate UDCA as a potential TGF-β inhibitor to enhance antitumor immunity. © 2022. The Author(s).
- Cancer Research,
- Cell Biology
A stromal Integrated Stress Response activates perivascular cancer-associated fibroblasts to drive angiogenesis and tumour progression.
In Nature Cell Biology on 1 June 2022 by Verginadis, I. I., Avgousti, H., et al.
PubMed
Bidirectional signalling between the tumour and stroma shapes tumour aggressiveness and metastasis. ATF4 is a major effector of the Integrated Stress Response, a homeostatic mechanism that couples cell growth and survival to bioenergetic demands. Using conditional knockout ATF4 mice, we show that global, or fibroblast-specific loss of host ATF4, results in deficient vascularization and a pronounced growth delay of syngeneic melanoma and pancreatic tumours. Single-cell transcriptomics of tumours grown in Atf4Δ/Δ mice uncovered a reduction in activation markers in perivascular cancer-associated fibroblasts (CAFs). Atf4Δ/Δ fibroblasts displayed significant defects in collagen biosynthesis and deposition and a reduced ability to support angiogenesis. Mechanistically, ATF4 regulates the expression of the Col1a1 gene and levels of glycine and proline, the major amino acids of collagen. Analyses of human melanoma and pancreatic tumours revealed a strong correlation between ATF4 and collagen levels. Our findings establish stromal ATF4 as a key driver of CAF functionality, malignant progression and metastasis. © 2022. The Author(s).
- FC/FACS,
- Cancer Research
Remodeling the tumor microenvironment via blockade of LAIR-1 and TGF-β signaling enables PD-L1-mediated tumor eradication.
In The Journal of Clinical Investigation on 15 April 2022 by Horn, L. A., Chariou, P. L., et al.
PubMed
Collagens in the extracellular matrix (ECM) provide a physical barrier to tumor immune infiltration, while also acting as a ligand for immune inhibitory receptors. Transforming growth factor-β (TGF-β) is a key contributor to shaping the ECM by stimulating the production and remodeling of collagens. TGF-β activation signatures and collagen-rich environments have both been associated with T cell exclusion and lack of responses to immunotherapy. Here, we describe the effect of targeting collagens that signal through the inhibitory leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) in combination with blockade of TGF-β and programmed cell death ligand 1 (PD-L1). This approach remodeled the tumor collagenous matrix, enhanced tumor infiltration and activation of CD8+ T cells, and repolarized suppressive macrophage populations, resulting in high cure rates and long-term tumor-specific protection across murine models of colon and mammary carcinoma. The results highlight the advantage of direct targeting of ECM components in combination with immune checkpoint blockade therapy.
