InVivoMAb anti-mouse CTLA-4 (CD152)
Product Details
The 9D9 monoclonal antibody reacts with mouse CTLA-4 (cytotoxic T lymphocyte antigen-4) also known as CD152. CTLA-4 is a 33 kDa cell surface receptor encoded by the Ctla4 gene that belongs to the CD28 family of the Ig superfamily. CTLA-4 is expressed on activated T and B lymphocytes. CTLA-4 is structurally similar to the T-cell co-stimulatory protein, CD28, and both molecules bind to the B7 family members B7-1 (CD80) and B7-2 (CD86). Upon ligand binding, CTLA-4 negatively regulates cell-mediated immune responses. CTLA-4 plays roles in induction and/or maintenance of immunological tolerance, thymocyte development, and regulation of protective immunity. The critical role of CTLA-4 in immune down-regulation has been demonstrated in CTLA-4 deficient mice, which succumb at 3-5 weeks of age due to the development of a lymphoproliferative disease. CTLA-4 is among a group of inhibitory receptors being explored as cancer treatment targets through immune checkpoint blockade. This CTLA-4 antibody has been extensively used in blocking/neutralization experiments and findings from a range of tumor models have established that the in vivo treatment of 9D9 monoclonal antibody results in intra-tumoral regulatory T cell depletion.Specifications
| Isotype | Mouse IgG2b |
|---|---|
| Recommended Isotype Control(s) | InVivoMAb mouse IgG2b isotype control, unknown specificity |
| Recommended Dilution Buffer | InVivoPure pH 7.0 Dilution Buffer |
| Conjugation | This product is unconjugated. Conjugation is available via our Antibody Conjugation Services. |
| Immunogen | Not available or unknown |
| Reported Applications |
in vivo CTLA-4 neutralization Western blot in vivo intra-tumoral regulatory T cell depletion |
| Formulation |
PBS, pH 7.0 Contains no stabilizers or preservatives |
| Endotoxin |
<2EU/mg (<0.002EU/Ī¼g) Determined by LAL gel clotting assay |
| Purity |
>95% Determined by SDS-PAGE |
| Sterility | 0.2 Āµm filtration |
| Production | Purified from cell culture supernatant in an animal-free facility |
| Purification | Protein A |
| RRID | AB_10949609 |
| Molecular Weight | 150 kDa |
| Storage | The antibody solution should be stored at the stock concentration at 4Ā°C. Do not freeze. |
Additional Formats
Recommended Products
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Recommended Isotype Control(s)
InVivoMAb mouse IgG2b isotype control, unknown specificity
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Recommended Dilution Buffer
InVivoPure pH 7.0 Dilution Buffer
in vivo CTLA-4 neutralization
Dai, M., et al. (2015). "Curing mice with large tumors by locally delivering combinations of immunomodulatory antibodies" Clin Cancer Res 21(5): 1127-1138. PubMed
PURPOSE: Immunomodulatory mAbs can treat cancer, but cures are rare except for small tumors. Our objective was to explore whether the therapeutic window increases by combining mAbs with different modes of action and injecting them into tumors. EXPERIMENTAL DESIGN: Combinations of mAbs to CD137/PD-1/CTLA-4 or CD137/PD-1/CTLA-4/CD19 were administrated intratumorally to mice with syngeneic tumors (B16 and SW1 melanoma, TC1 lung carcinoma), including tumors with a mean surface of approximately 80 mm(2). Survival and tumor growth were assessed. Immunologic responses were evaluated using flow cytometry and qRT-PCR. RESULTS: More than 50% of tumor-bearing mice had complete regression and long-term survival after tumor injection with mAbs recognizing CD137/PD-1/CTLA-4/CD19 with similar responses in three models. Intratumoral injection was more efficacious than intraperitoneal injection in causing rejection also of untreated tumors in the same mice. The three-mAb combination could also induce regression, but was less efficacious. There were few side effects, and therapy-resistant tumors were not observed. Transplanted tumor cells rapidly caused a Th2 response with increased CD19 cells. Successful therapy shifted this response to the Th1 phenotype with decreased CD19 cells and increased numbers of long-term memory CD8 effector cells and T cells making IFNgamma and TNFalpha. CONCLUSIONS: Intratumoral injection of mAbs recognizing CD137/PD-1/CTLA-4/CD19 can eradicate established tumors and reverse a Th2 response with tumor-associated CD19 cells to Th1 immunity, whereas a combination lacking anti-CD19 is less effective. There are several human cancers for which a similar approach may provide clinical benefit.
in vivo CTLA-4 neutralization
Zippelius, A., et al. (2015). "Induced PD-L1 expression mediates acquired resistance to agonistic anti-CD40 treatment" Cancer Immunol Res 3(3): 236-244. PubMed
CD40 stimulation on antigen-presenting cells (APC) allows direct activation of CD8(+) cytotoxic T cells, independent of CD4(+) T-cell help. Agonistic anti-CD40 antibodies have been demonstrated to induce beneficial antitumor T-cell responses in mouse models of cancer and early clinical trials. We report here that anti-CD40 treatment induces programmed death ligand-1 (PD-L1) upregulation on tumor-infiltrating monocytes and macrophages, which was strictly dependent on T cells and IFNgamma. PD-L1 expression could be counteracted by coadministration of antibodies blocking the PD-1 (programmed death-1)/PD-L1 axis as shown for T cells from tumor models and human donors. The combined treatment was highly synergistic and induced complete tumor rejection in about 50% of mice bearing MC-38 colon and EMT-6 breast tumors. Mechanistically, this was reflected by a strong increase of IFNgamma and granzyme-B production in intratumoral CD8(+) T cells. Concomitant CTLA-4 blockade further improved rejection of established tumors in mice. This study uncovers a novel mechanism of acquired resistance upon agonistic CD40 stimulation and proposes that the concomitant blockade of the PD-1/PD-L1 axis is a viable therapeutic strategy to optimize clinical outcomes.
in vivo CTLA-4 neutralization
Redmond, W. L., et al. (2014). "Combined targeting of costimulatory (OX40) and coinhibitory (CTLA-4) pathways elicits potent effector T cells capable of driving robust antitumor immunity" Cancer Immunol Res 2(2): 142-153. PubMed
Ligation of the TNF receptor family costimulatory molecule OX40 (CD134) with an agonist anti-OX40 monoclonal antibody (mAb) enhances antitumor immunity by augmenting T-cell differentiation as well as turning off the suppressive activity of the FoxP3(+)CD4(+) regulatory T cells (Treg). In addition, antibody-mediated blockade of the checkpoint inhibitor CTLA-4 releases the ābrakesā on T cells to augment tumor immunotherapy. However, monotherapy with these agents has limited therapeutic benefit particularly against poorly immunogenic murine tumors. Therefore, we examined whether the administration of agonist anti-OX40 therapy in the presence of CTLA-4 blockade would enhance tumor immunotherapy. Combined anti-OX40/anti-CTLA-4 immunotherapy significantly enhanced tumor regression and the survival of tumor-bearing hosts in a CD4 and CD8 T cell-dependent manner. Mechanistic studies revealed that the combination immunotherapy directed the expansion of effector T-bet(high)/Eomes(high) granzyme B(+) CD8 T cells. Dual immunotherapy also induced distinct populations of Th1 [interleukin (IL)-2, IFN-gamma], and, surprisingly, Th2 (IL-4, IL-5, and IL-13) CD4 T cells exhibiting increased T-bet and Gata-3 expression. Furthermore, IL-4 blockade inhibited the Th2 response, while maintaining the Th1 CD4 and effector CD8 T cells that enhanced tumor-free survival. These data demonstrate that refining the global T-cell response during combination immunotherapy can further enhance the therapeutic efficacy of these agents.
in vivo CTLA-4 neutralization
Condamine, T., et al. (2014). "ER stress regulates myeloid-derived suppressor cell fate through TRAIL-R-mediated apoptosis" J Clin Invest 124(6): 2626-2639. PubMed
Myeloid-derived suppressor cells (MDSCs) dampen the immune response thorough inhibition of T cell activation and proliferation and often are expanded in pathological conditions. Here, we studied the fate of MDSCs in cancer. Unexpectedly, MDSCs had lower viability and a shorter half-life in tumor-bearing mice compared with neutrophils and monocytes. The reduction of MDSC viability was due to increased apoptosis, which was mediated by increased expression of TNF-related apoptosis-induced ligand receptors (TRAIL-Rs) in these cells. Targeting TRAIL-Rs in naive mice did not affect myeloid cell populations, but it dramatically reduced the presence of MDSCs and improved immune responses in tumor-bearing mice. Treatment of myeloid cells with proinflammatory cytokines did not affect TRAIL-R expression; however, induction of ER stress in myeloid cells recapitulated changes in TRAIL-R expression observed in tumor-bearing hosts. The ER stress response was detected in MDSCs isolated from cancer patients and tumor-bearing mice, but not in control neutrophils or monocytes, and blockade of ER stress abrogated tumor-associated changes in TRAIL-Rs. Together, these data indicate that MDSC pathophysiology is linked to ER stress, which shortens the lifespan of these cells in the periphery and promotes expansion in BM. Furthermore, TRAIL-Rs can be considered as potential targets for selectively inhibiting MDSCs.
in vivo CTLA-4 neutralization
Muller, P., et al. (2014). "Microtubule-depolymerizing agents used in antibody-drug conjugates induce antitumor immunity by stimulation of dendritic cells" Cancer Immunol Res 2(8): 741-755. PubMed
Antibody-drug conjugates (ADC) are emerging as powerful treatment strategies with outstanding target-specificity and high therapeutic activity in patients with cancer. Brentuximab vedotin represents a first-in-class ADC directed against CD30(+) malignancies. We hypothesized that its sustained clinical responses could be related to the stimulation of an anticancer immune response. In this study, we demonstrate that the dolastatin family of microtubule inhibitors, from which the cytotoxic component of brentuximab vedotin is derived, comprises potent inducers of phenotypic and functional dendritic cell (DC) maturation. In addition to the direct cytotoxic effect on tumor cells, dolastatins efficiently promoted antigen uptake and migration of tumor-resident DCs to the tumor-draining lymph nodes. Exposure of murine and human DCs to dolastatins significantly increased their capacity to prime T cells. Underlining the requirement of an intact host immune system for the full therapeutic benefit of dolastatins, the antitumor effect was far less pronounced in immunocompromised mice. We observed substantial therapeutic synergies when combining dolastatins with tumor antigen-specific vaccination or blockade of the PD-1-PD-L1 and CTLA-4 coinhibitory pathways. Ultimately, treatment with ADCs using dolastatins induces DC homing and activates cellular antitumor immune responses in patients. Our data reveal a novel mechanism of action for dolastatins and provide a strong rationale for clinical treatment regimens combining dolastatin-based therapies, such as brentuximab vedotin, with immune-based therapies.
in vivo CTLA-4 neutralization
Bulliard, Y., et al. (2013). "Activating Fc gamma receptors contribute to the antitumor activities of immunoregulatory receptor-targeting antibodies" J Exp Med 210(9): 1685-1693. PubMed
Fc gamma receptor (FcgammaR) coengagement can facilitate antibody-mediated receptor activation in target cells. In particular, agonistic antibodies that target tumor necrosis factor receptor (TNFR) family members have shown dependence on expression of the inhibitory FcgammaR, FcgammaRIIB. It remains unclear if engagement of FcgammaRIIB also extends to the activities of antibodies targeting immunoregulatory TNFRs expressed by T cells. We have explored the requirement for activating and inhibitory FcgammaRs for the antitumor effects of antibodies targeting the TNFR glucocorticoid-induced TNFR-related protein (GITR; TNFRSF18; CD357) expressed on activated and regulatory T cells (T reg cells). We found that although FcgammaRIIB was dispensable for the in vivo efficacy of anti-GITR antibodies, in contrast, activating FcgammaRs were essential. Surprisingly, the dependence on activating FcgammaRs extended to an antibody targeting the non-TNFR receptor CTLA-4 (CD152) that acts as a negative regulator of T cell immunity. We define a common mechanism that correlated with tumor efficacy, whereby antibodies that coengaged activating FcgammaRs expressed by tumor-associated leukocytes facilitated the selective elimination of intratumoral T cell populations, particularly T reg cells. These findings may have broad implications for antibody engineering efforts aimed at enhancing the therapeutic activity of immunomodulatory antibodies.
in vivo CTLA-4 neutralization
Wei, H., et al. (2013). "Combinatorial PD-1 blockade and CD137 activation has therapeutic efficacy in murine cancer models and synergizes with cisplatin" PLoS One 8(12): e84927. PubMed
90 days (and was probably curative) by a mechanism which included a systemic CD8(+) T cell response with tumor specificity and immunological memory. Strikingly, combined treatment of cisplatin and CD137/PD-1 mAb also gave rise to the long-term survival of mice with established TC1 lung tumors. A similar combination of the 2 mAbs and cisplatin should be considered for clinical ātranslationā.ā}ā data-sheets-userformat=ā{ā2ā³:14851,ā3ā:{ā1ā³:0},ā4ā:{ā1ā³:2,ā2ā³:16777215},ā12ā³:0,ā14ā:{ā1ā³:2,ā2ā³:1521491},ā15ā³:āRoboto, sans-serifā,ā16ā³:12}ā>There is an urgent need for improved therapy for advanced ovarian carcinoma, which may be met by administering immune-modulatory monoclonal antibodies (mAbs) to generate a tumor-destructive immune response. Using the ID8 mouse ovarian cancer model, we investigated the therapeutic efficacy of various mAb combinations in mice with intraperitoneal (i.p.) tumor established by transplanting 3 x 10(6) ID8 cells 10 days previously. While most of the tested mAbs were ineffective when given individually or together, the data confirm our previous finding that 2 i.p. injections of a combination of anti-CD137 with anti-PD-1 mAbs doubles overall survival. Mice treated with this mAb combination have a significantly increased frequency and total number of CD8(+) T cells both in the peritoneal lavage and spleens, and these cells are functional as demonstrated by antigen-specific cytolytic activity and IFN-gamma production. While administration of anti-CD137 mAb as a single agent similarly increases CD8(+) T cells, these have no functional activity, which may be attributed to up-regulation of co-inhibitory PD-1 and TIM-3 molecules induced by CD137. Addition of the anti-cancer drug cisplatin to the 2 mAb combination increased overall survival >90 days (and was probably curative) by a mechanism which included a systemic CD8(+) T cell response with tumor specificity and immunological memory. Strikingly, combined treatment of cisplatin and CD137/PD-1 mAb also gave rise to the long-term survival of mice with established TC1 lung tumors. A similar combination of the 2 mAbs and cisplatin should be considered for clinical ātranslationā.
in vivo CTLA-4 neutralization
Dai, M., et al. (2013). "Long-lasting complete regression of established mouse tumors by counteracting Th2 inflammation" J Immunother 36(4): 248-257. PubMed
40% of mice with SW1 tumors remained healthy >150 days after last treatment and are probably cured. Therapeutic efficacy was associated with a systemic immune response with memory and antigen specificity, required CD4 cells and involved CD8 cells and NK cells to a less extent. The 3 mAb combination significantly decreased CD19 cells at tumor sites, increased IFN-gamma and TNF-alpha producing CD4 and CD8 T cells and mature CD86 dendritic cells (DC), and it increased the ratios of effector CD4 and CD8 T cells to CD4Foxp3 regulatory T (Treg) cells and to CD11bGr-1 myeloid suppressor cells (MDSC). This is consistent with shifting the tumor microenvironment from an immunosuppressive Th2 to an immunostimulatory Th1 type and is further supported by PCR data. Adding an anti-CD19 mAb to the 3 mAb combination in the SW1 model further increased therapeutic efficacy. Data from ongoing experiments show that intratumoral injection of a combination of mAbs to CD137PD-1CTLA4CD19 can induce complete regression and dramatically prolong survival also in the TC1 carcinoma and B16 melanoma models, suggesting that the approach has general validity.ā}ā data-sheets-userformat=ā{ā2ā³:14851,ā3ā:{ā1ā³:0},ā4ā:{ā1ā³:2,ā2ā³:16777215},ā12ā³:0,ā14ā:{ā1ā³:2,ā2ā³:1521491},ā15ā³:āRoboto, sans-serifā,ā16ā³:12}ā>Mice with intraperitoneal ID8 ovarian carcinoma or subcutaneous SW1 melanoma were injected with monoclonal antibodies (mAbs) to CD137PD-1CTLA4 7-15 days after tumor initiation. Survival of mice with ID8 tumors tripled and >40% of mice with SW1 tumors remained healthy >150 days after last treatment and are probably cured. Therapeutic efficacy was associated with a systemic immune response with memory and antigen specificity, required CD4 cells and involved CD8 cells and NK cells to a less extent. The 3 mAb combination significantly decreased CD19 cells at tumor sites, increased IFN-gamma and TNF-alpha producing CD4 and CD8 T cells and mature CD86 dendritic cells (DC), and it increased the ratios of effector CD4 and CD8 T cells to CD4Foxp3 regulatory T (Treg) cells and to CD11bGr-1 myeloid suppressor cells (MDSC). This is consistent with shifting the tumor microenvironment from an immunosuppressive Th2 to an immunostimulatory Th1 type and is further supported by PCR data. Adding an anti-CD19 mAb to the 3 mAb combination in the SW1 model further increased therapeutic efficacy. Data from ongoing experiments show that intratumoral injection of a combination of mAbs to CD137PD-1CTLA4CD19 can induce complete regression and dramatically prolong survival also in the TC1 carcinoma and B16 melanoma models, suggesting that the approach has general validity.
in vivo CTLA-4 neutralization
Hooijkaas, A., et al. (2012). "Selective BRAF inhibition decreases tumor-resident lymphocyte frequencies in a mouse model of human melanoma" Oncoimmunology 1(5): 609-617. PubMed
The development of targeted therapies and immunotherapies has markedly advanced the treatment of metastasized melanoma. While treatment with selective BRAF(V600E) inhibitors (like vemurafenib or dabrafenib) leads to high response rates but short response duration, CTLA-4 blocking therapies induce sustained responses, but only in a limited number of patients. The combination of these diametric treatment approaches may further improve survival, but pre-clinical data concerning this approach is limited. We investigated, using Tyr::CreER(T2)PTEN(F-/-)BRAF(F-V600E/+) inducible melanoma mice, whether BRAF(V600E) inhibition can synergize with anti-CTLA-4 mAb treatment, focusing on the interaction between the BRAF(V600E) inhibitor PLX4720 and the immune system. While PLX4720 treatment strongly decreased tumor growth, it did not induce cell death in BRAF(V600E)/PTEN(-/-) melanomas. More strikingly, PLX4720 treatment led to a decreased frequency of tumor-resident T cells, NK-cells, MDSCs and macrophages, which could not be restored by the addition of anti-CTLA-4 mAb. As this effect was not observed upon treatment of BRAF wild-type B16F10 tumors, we conclude that the decreased frequency of immune cells correlates to BRAF(V600E) inhibition in tumor cells and is not due to an off-target effect of PLX4720 on immune cells. Furthermore, anti-CTLA-4 mAb treatment of inducible melanoma mice treated with PLX4720 did not result in enhanced tumor control, while anti-CTLA-4 mAb treatment did improve the effect of tumor-vaccination in B16F10-inoculated mice. Our data suggest that vemurafenib may negatively affect the immune activity within the tumor. Therefore, the potential effect of targeted therapy on the tumor-microenvironment should be taken into consideration in the design of clinical trials combining targeted and immunotherapy.
in vivo CTLA-4 neutralization
Curran, M. A., et al. (2011). "Combination CTLA-4 blockade and 4-1BB activation enhances tumor rejection by increasing T-cell infiltration, proliferation, and cytokine production" PLoS One 6(4): e19499. PubMed
BACKGROUND: The co-inhibitory receptor Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) attenuates immune responses and prevent autoimmunity, however, tumors exploit this pathway to evade the host T-cell response. The T-cell co-stimulatory receptor 4-1BB is transiently upregulated on T-cells following activation and increases their proliferation and inflammatory cytokine production when engaged. Antibodies which block CTLA-4 or which activate 4-1BB can promote the rejection of some murine tumors, but fail to cure poorly immunogenic tumors like B16 melanoma as single agents. METHODOLOGY/PRINCIPAL FINDINGS: We find that combining alphaCTLA-4 and alpha4-1BB antibodies in the context of a Flt3-ligand, but not a GM-CSF, based B16 melanoma vaccine promoted synergistic levels of tumor rejection. 4-1BB activation elicited strong infiltration of CD8+ T-cells into the tumor and drove the proliferation of these cells, while CTLA-4 blockade did the same for CD4+ effector T-cells. Anti-4-1BB also depressed regulatory T-cell infiltration of tumors. 4-1BB activation strongly stimulated inflammatory cytokine production in the vaccine and tumor draining lymph nodes and in the tumor itself. The addition of CTLA-4 blockade further increased IFN-gamma production from CD4+ effector T-cells in the vaccine draining node and the tumor. Anti 4-1BB treatment, with or without CTLA-4 blockade, induced approximately 75% of CD8+ and 45% of CD4+ effector T-cells in the tumor to express the killer cell lectin-like receptor G1 (KLRG1). Tumors treated with combination antibody therapy showed 1.7-fold greater infiltration by these KLRG1+CD4+ effector T-cells than did those treated with alpha4-1BB alone. CONCLUSIONS/SIGNIFICANCE: This study shows that combining T-cell co-inhibitory blockade with alphaCTLA-4 and active co-stimulation with alpha4-1BB promotes rejection of B16 melanoma in the context of a suitable vaccine. In addition, we identify KLRG1 as a useful marker for monitoring the anti-tumor immune response elicited by this therapy. These findings should aid in the design of future trials for the immunotherapy of melanoma.
in vivo CTLA-4 neutralization
Balachandran, V. P., et al. (2011). "Imatinib potentiates antitumor T cell responses in gastrointestinal stromal tumor through the inhibition of Ido" Nat Med 17(9): 1094-1100. PubMed
Imatinib mesylate targets mutated KIT oncoproteins in gastrointestinal stromal tumor (GIST) and produces a clinical response in 80% of patients. The mechanism is believed to depend predominantly on the inhibition of KIT-driven signals for tumor-cell survival and proliferation. Using a mouse model of spontaneous GIST, we found that the immune system contributes substantially to the antitumor effects of imatinib. Imatinib therapy activated CD8(+) T cells and induced regulatory T cell (T(reg) cell) apoptosis within the tumor by reducing tumor-cell expression of the immunosuppressive enzyme indoleamine 2,3-dioxygenase (Ido). Concurrent immunotherapy augmented the efficacy of imatinib in mouse GIST. In freshly obtained human GIST specimens, the T cell profile correlated with imatinib sensitivity and IDO expression. Thus, T cells are crucial to the antitumor effects of imatinib in GIST, and concomitant immunotherapy may further improve outcomes in human cancers treated with targeted agents.
- Cancer Research,
Cancer therapy via neoepitope-specific monoclonal antibody cocktails.
In Cancer Immunology, Immunotherapy : CII on 31 May 2025 by Hartman, C. J., Mohamed, A. O., et al.
Cellular heterogeneity presents a significant challenge to cancer treatment. Antibody therapies targeting individual tumor-associated antigens can be extremely effective but are not suited for all patients and often fail against tumors with heterogeneous expression as tumor cells with low or no antigen expression escape targeting and develop resistance. Simultaneously targeting multiple tumor-specific proteins with multiple antibodies has the potential to overcome this barrier and improve efficacy, but relatively few widely expressed cancer-specific antigens are known. In contrast, neoepitopes, which arise from mutations unique to tumor cells, are considerably more abundant. However, since neoepitopes are not commonly shared between individuals, a patient-customized approach is necessary and motivates efforts to develop an efficient means to identify suitable target mutations and isolate neoepitope-specific monoclonal antibodies. Here, focusing on the latter goal, we use directed evolution in yeast and phage display systems to engineer antibodies from nonimmune, human antibody fragment libraries that are specific for neoepitopes previously reported in the B16F10 melanoma model. We demonstrate proof-of-concept for a pipeline that supports rapid isolation and functional enhancement of multiple neoepitope peptide-targeted monoclonal antibodies and demonstrate their robust binding to B16F10 cells and potent effector functions in vitro. These antibodies were combined and evaluated in vivo for anticancer activity in tumor-bearing mice, where they suppressed B16F10 tumor growth and prolonged survival. These findings emphasize the potential for clinical application of patient-customized antibody cocktails in the treatment of the many cancers poorly addressed by current therapies. Ā© 2025. The Author(s).
- Cancer Research,
- Immunology and Microbiology
Simultaneous co-delivery of Ginsenoside Rg3 and imiquimod from PLGA nanoparticles for effective breast cancer immunotherapy.
In IScience on 16 May 2025 by Hu, C., Nong, S., et al.
Breast cancer is a fatal malignancy facing human health, with most patients experiencing recurrence and resistance to chemotherapy. The immunosuppressive tumor microenvironment (TME) greatly limits the actual outcome of immunotherapy. This study aimed to develop a modality of theranostics nanoparticles for breast cancer based on a near-infrared light-triggered nanoparticle for the targeted delivery of ginsenoside Rg3 and immune adjuvants imiquimod (R837) for effective breast cancer immunotherapy. Folate-receptor (FA) targeting IR780-R837/ginsenoside Rg3-perfluorohexane (PFH) @ polyethylene glycol (PEG)-poly (lactide-co-glycolic acid) (PLGA) nanoparticles (FA-NPs) can be activated by near-infrared laser irradiation in tumors, which leads to rapid release of ginsenoside Rg3 and R837 in the regions with high expression of folate receptors and glucose transporter 1 (GLUT1). Meanwhile, the nanoparticles can be used as dual-mode contrast agents for photoacoustic and ultrasound imaging. This strategy provides a strong immune memory effect, which can prevent tumor recurrence after eliminating the initial tumor. Ā© 2025 The Author(s).
- FC/FACS,
- Cancer Research,
- Genetics,
- Immunology and Microbiology
Loss of MNX1 Sensitizes Tumors to Cytotoxic T Cells by Degradation of PD-L1 mRNA.
In Advanced Science (Weinheim, Baden-Wurttemberg, Germany) on 1 March 2025 by Li, Z., Chen, L., et al.
Immune checkpoint blockade (ICB) therapy, targeting programmed cell death ligand-1 (PD-L1)/programmed cell death protein 1 (PD-1) axis and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), has exhibited amazing clinical outcomes in various types of cancers. However, only a small portion of patients benefit from ICB therapy, indicating that the mechanism underlying immune checkpoint is still unclear. Here, it is reported that motor neuron and pancreas homeobox 1 (MNX1), a homeobox domain-containing transcription factor, contributesĀ to the tumor immune escape. MNX1 increases PD-L1 expression in cancer cells by stabilizing PD-L1 mRNA rather than activating transcription. Mechanistically, MNX1 exists in the cytoplasm of cancer cells and interacts with Y-box binding protein 1 (YBX1), a multifunctional DNA/RNA-binding protein, to enhance the binding of YBX1 to PD-L1 mRNA. MNX1 ablation activates cytotoxic T cell-mediated anti-tumor immunity and sensitizes CTLA-4 blockade therapy. Moreover, MNX1 also facilitates tumor progression in an immune-independent manner in cancer cells. In addition, MNX1 is upregulated by its adjacent long non-coding RNA MNX1-AS1 via HECT and RLD domain containing E3 ubiquitin protein ligase 2 (HERC2). Together, these results reveal MNX1 as a novel immune checkpoint regulator with promising therapeutic potential. Ā© 2025 The Author(s). Advanced Science published by WileyāVCH GmbH.
- Cancer Research,
- Genetics,
- Immunology and Microbiology
Alterations in PD-L1 succinylation shape anti-tumor immune responses in melanoma.
In Nature Genetics on 1 March 2025 by Liang, L., Kuang, X., et al.
Tumors undergo metabolic reprogramming to meet the energetic, synthetic and redox demands essential for malignancy, often characterized by increased glycolysis and lactate production. However, the role of mitochondrial metabolism in tumor immunity remains unclear. The present study integrates spatial transcriptomics, bulk transcriptomics and proteomics, revealing a strong link between the metabolite succinyl-CoA and tumor immunity as well as the efficacy of anti-programmed cell death protein-1 (PD-1) therapy in patients with melanoma. Elevated succinyl-CoA levels, through Ī±-ketoglutarate or succinate supplementation, enhanced T cell-mediated tumor elimination, both in vitro and in vivo. Mechanistically, succinylation of the ligand of PD-1 (PD-L1) at lysine 129 led to its degradation. Increased carnitine palmitoyltransferase 1A (CPT1A), identified as a succinyltransferase for PD-L1, boosted anti-tumor activity. Preclinically, bezafibrate, a hyperlipidemia drug, upregulated CPT1A and synergized with CTLA-4 monoclonal antibody to inhibit tumor growth. Clinically, higher PD-L1 and lower CPT1A levels in tumors correlated with better anti-PD-1 therapy responses, suggesting potential biomarkers for prediction of treatment efficacy. Ā© 2025. The Author(s).
- Mus musculus (House mouse)
Intratumor heterogeneity in KRAS signaling shapes treatment resistance.
In IScience on 21 February 2025 by Petrenko, O., Kirillov, V., et al.
KRAS mutations are linked to some of the deadliest forms of cancer. Pharmacological studies suggest that co-targeting KRAS with feedback/bypass pathways could lead to enhanced anti-tumor activity. The underlying premise is that cancers display a deep-rooted hypersensitivity to KRAS inactivation. Here, we investigate the role of intratumor heterogeneity in pancreatic ductal adenocarcinoma, focusing on oncogenic KRAS addiction and treatment resistance. Integrated analysis of single-cell and bulk RNA sequencing data reveals that most tumors display a mixture of cells with vastly different degrees of KRAS dependency. We identify distinct cell populations that vary in their gene expression patterns pertaining to the predicted level of KRAS signaling activity, cell growth, and differentiation commitment within each tumor. Selective targeting of mutant KRAS suppresses the growth of tumor cells with high RAS/mitogen-activated protein kinase (MAPK) activity while sparing pre-existing subsets with low RAS signaling activity, necessitating alternative treatments. Combination immunotherapy leads to durable tumor regression in preclinical models. Ā© 2024 The Author(s).
- Cancer Research,
- Immunology and Microbiology
Development of Syngeneic Murine Glioma Models with Somatic Mismatch Repair Deficiency to Study Therapeutic Responses to Alkylating Agents and Immunotherapy.
In Current Protocols on 1 February 2025 by Bhatt, D., Sundaram, R. K., et al.
Glioblastoma (GBM) carries a dismal prognosis, with a median survival of less than 15 months. Temozolomide (TMZ), the standard frontline chemotherapeutic for GBM, is an alkylating agent that generates DNA O6-methylguanine (O6MeG) lesions. Without O6MeG-methyltransferase (MGMT), this lesion triggers the mismatch repair (MMR) pathway and leads to cytotoxicity via futile cycling. TMZ resistance frequently arises via the somatic acquisition of MMR deficiency (MMRd). Moreover, DNA-damaging agents have been shown capable of increasing tumor immunogenicity and improving response to immune checkpoint blockade (ICB), which has had limited success in glioma. The study of how alkylating chemotherapy such as TMZ impacts antitumor immunity in glioma has been hindered by a lack of immunocompetent models that incorporate relevant DNA repair genotypes. Here, we used CRISPR/Cas9 to generate models isogenic for knockout (KO) of Mlh1 in the syngeneic SB28 murine glioma cell line. MMR KO models readily formed intracranial tumors and exhibited in vitro and in vivo resistance to TMZ. In contrast, MMR KO cells maintained sensitivity to KL-50, a newly developed alkylating compound that exerts MGMT-dependent, MMR-independent cytotoxicity. Lastly, MMR KO tumors remained resistant to ICB, mirroring the lack of response seen in patients with somatic MMRd GBM. The development of syngeneic, immunologically cold glioma models with somatic loss of MMR will facilitate future studies on the immunomodulatory effects of alkylating agents in relevant DNA repair contexts, which will be vital for optimizing combinations with ICB. Ā© 2025 Wiley Periodicals LLC. Basic Protocol 1: Validation of mismatch repair knockouts and in vitro sensitivity to alkylating agents Basic Protocol 2: Stereotaxic injection of isogenic SB28 cells in female C57BL/6J mice and in vivo treatment. Ā© 2025 Wiley Periodicals LLC.
- Immunology and Microbiology
Polymeric Multivalent Fc Binding Peptides-Fabricated Clinical Compounding Bispecific Antibody Potentiates Dual Immunotherapy Targeting PD1 and CTLA-4.
In Advanced Science (Weinheim, Baden-Wurttemberg, Germany) on 1 January 2025 by Liu, Z., Chu, H., et al.
Dual Opdivo plus Yervoy immunotherapy, targeting the immune checkpoints PD1 and CTLA-4, is successful in clinical use. However, it is associated with a high incidence of adverse events, and its therapeutic efficacy needs improving. In this study, polymeric multivalent Fc-binding peptides (PLG-Fc-III-4C) are employed to fabricate a bispecific antibody (PD1/CTLA-4 BsAb) to potentiate dual immunotherapy targeting PD1 and CTLA-4. The PD1/CTLA-4 BsAb is prepared by mixing PLG-Fc-III-4C with aPD1 and aCTLA-4 in an aqueous solution for 3 h using the clinically optimal 3:1 proportion of aPD1 to aCTLA-4. PD1/CTLA-4 BsAb significantly inhibits tumors in MC38 colon cancer-bearing mice more effectively than the combination of aPD1 and aCTLA-4, with tumor suppression rates of 96.8% and 77.3%, respectively. It also induces a higher percentage of CD8+ T cells and increases the secretion of effector cytokines while reducing Treg levels in tumors compared to phosphate-buffered saline, indicating significant tumor immunity regulation. Mechanistically, a 6.3-fold increase in PD1/CTLA-4 BsAb accumulation in tumors due to the tumor targeting ability of aPD1, and the PD1/CTLA-4 BsAb significantly reduces the adverse colitis event in healthy mice, compared to aPD1 and aCTLA-4. Thus, these findings provide a novel approach to enhance antitumor therapy using aPD1 and aCTLA-4. Ā© 2024 The Author(s). Advanced Science published by WileyāVCH GmbH.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
FSTL3 is a biomarker of poor prognosis and is associated with immunotherapy resistance in ovarian cancer
Preprint on BioRxiv : the Preprint Server for Biology on 12 December 2024 by Chauvin, M., Tromelin, E., et al.
High-grade serous ovarian carcinoma (HGSOC), is associated with high mortality rates due to late-stage diagnosis and limited treatment options. We investigated the role of FSTL3 in ovarian cancer progression both as a prognostic biomarker and as a potential therapeutic target. We measured levels of follistatin (FST) and follistatin-like 3 (FSTL3) in 96 ovarian cancer patient ascites samples and found that FSTL3 overexpression was more predominant than FST and associated with poorer survival outcomes. Mice implanted with an HGSOC syngeneic cell line bearing common alterations in ovarian cancer (KRAS G12V , P53 R172H , CCNE1 oe , AKT2 oe ) had increasing levels of FST and FSTL3 in serum during tumor growth. Further alteration of this model to generate a knockout of FST (KPCA.FSTKO) and an overexpression of human FSTL3 (KPCA.FSTKO_hFSTL3), revealed that FSTL3 expression was associated with a more fibrotic tumor microenvironment, correlating with an increased abundance of cancer-associated myofibroblasts (myCAFs), and cancer cells with a more mesenchymal phenotype. Tumors overexpressing FSTL3 had less immunocyte infiltration and a significantly reduced intratumoral T-cell abundance (CD4+, CD8+). FSTL3 overexpression completely abrogated tumor response to PPC treatment (Prexasertib combined with PD-1 and CTLA-4 blockade) compared to controls, suggesting that FSTL3 may be involved in immunotherapy resistance. In conclusion, this study suggests a role for FSTL3 as a prognostic marker and as therapeutic target in HGSOC, where it may play a role in promoting a mesenchymal tumor phenotype, maintaining an immunosuppressive tumor microenvironment, and driving immunotherapy resistance. Highlights High FSTL3 levels are associated with poor outcomes in ovarian cancer. Serum levels of FSTL3 increase during tumor growth and reflect tumor burden and therapy response. Overexpression of FSTL3 in cancer cells promotes a fibrotic tumor microenvironment and immunocyte exclusion. Overexpression of FSTL3 in tumors induces resistance to Chk1 and immune checkpoint inhibitor combination therapy. Graphical abstract
- Mus musculus (House mouse),
- Cancer Research
Identification of VISTA regulators in macrophages mediating cancer cell survival.
In Science Advances on 29 November 2024 by Abdrabou, A. M., Ahmed, S., et al.
Numerous human cancers have exhibited the ability to elude immune checkpoint blockade (ICB) therapies. This type of resistance can be mediated by immune-suppressive macrophages that limit antitumor immunity in the tumor microenvironment (TME). Here, we elucidate a strategy to shift macrophages into a proinflammatory state that down-regulates V domain immunoglobulin suppressor of T cell activation (VISTA) via inhibiting AhR and IRAK1. We used a high-throughput microfluidic platform combined with a genome-wide CRISPR knockout screen to identify regulators of VISTA levels. Functional characterization showed that the knockdown of these hits diminished VISTA surface levels on macrophages and sustained an antitumor phenotype. Furthermore, targeting of both AhR and IRAK1 in mouse models overcame resistance to ICB treatment. Tumor immunophenotyping indicated that infiltration of cytotoxic CD8+ cells, natural killer cells, and antitumor macrophages was substantially increased in treated mice. Collectively, AhR and IRAK1 are implicated as regulators of VISTA that coordinate a multifaceted barrier to antitumor immune responses.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
Calcium nanoparticles target and activate T cells to enhance anti-tumor function.
In Nature Communications on 21 November 2024 by Yang, W., Feng, Z., et al.
Calcium signaling plays a crucial role in the activation of T lymphocytes. However, modulating calcium levels to control T cell activation in vivo remains a challenge. In this study, we investigate T cell activation using 12-myristate 13-acetate (PMA)-encapsulated CaCO3 nanoparticles. We find that anti-PD-1 antibody-conjugated CaCO3 nanoparticles can be internalized by T cells via receptor-mediated endocytosis and then gradually release calcium. This results in an increase in cytosolic calcium, which triggers the activation of NFAT and NF-ĪŗB pathways, especially when the surface of the CaCO3 nanoparticles is loaded with PMA. Animal studies demonstrate that the PMA-loaded calcium nanoparticles enhance the activation and proliferation of cytotoxic T cells, leading to improved tumor suppression without additional toxicity. When tested in metastatic tumor models, T cells loaded with the calcium nanoparticles prior to adoptive cell transfer control tumor growth better, resulting in prolonged animal survival. Our approach offers an alternative T cell activation strategy to potentiate immunotherapy by targeting a fundamental signaling pathway. Ā© 2024. The Author(s).
- In Vivo,
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
Oral reovirus reshapes the gut microbiome and enhances antitumor immunity in colon cancer.
In Nature Communications on 22 October 2024 by Lee, W. S., Lee, S. J., et al.
The route of oncolytic virotherapy is pivotal for immunotherapeutic efficacy in advanced cancers. In this preclinical study, an oncolytic reovirus (RC402) is orally administered to induce antitumor immunity. Oral reovirus treatment shows no gross toxicities and effectively suppresses multifocal tumor lesions. Orally administered reovirus interacts with the host immune system in the Peyer's patch of the terminal ileum, increases IgA+ antibody-secreting cells in the lamina propria through MAdCAM-1+ blood vessels, and reshapes the gut microbiome. Oral reovirus promotes antigen presentation, type I/II interferons, and T cell activation within distant tumors, but does not reach or directly infect tumor cells beyond the gastrointestinal tract. In contrast to intratumoral reovirus injection, the presence of the gut microbiome, Batf3+ dendritic cells, type I interferons, and CD8+ T cells are indispensable for orally administered reovirus-induced antitumor immunity. Oral reovirus treatment is most effective when combined with Ī±PD-1(L1) and/or Ī±CTLA-4, leading to complete colon tumor regression and protective immune memory. Collectively, oral reovirus virotherapy is a feasible and effective immunotherapeutic strategy in preclinical studies. Ā© 2024. The Author(s).
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
Delivery of extracellular vesicles loaded with immune checkpoint inhibitors for immunotherapeutic management of glioma.
In Materials Today. Bio on 1 October 2024 by Lin, S. W., Yu, C. P., et al.
Glioma is a common primary malignant brain tumor with low survival rate. Immunotherapy with immune checkpoints inhibitors (ICI) can be a choice for glioma management, and extracellular vesicles (EVs) are recognized as a potential drug delivery system for various disease management due to their enhanced barrier permeation ability and immunomodulatory effect. The aim of this study is to develop ICI-loaded EVs (ICI/EV) that have sufficient efficacy in managing glioma. Calcium phosphate particles (CaP) were used to stimulate the secretion of EVs from murine macrophage cells. CaP conditioning of cells showed an enhanced amount of EVs secretion and macrophage polarization toward a proinflammatory phenotype. The CaP-induced EVs were shown to polarize macrophages into proinflammatory phenotype in vitro, as correlated with the conditioning method. ICI/EVs were successfully prepared with high loading efficiency using the sonication method. The EVs can be distributed throughout the entire brain upon intranasal administration and facilitate ICIs distribution into glioma lesion. Combinatory treatment with ICI/EVs showed benefit in glioma-bearing mice by reducing their tumor volume and prolonging their survival. Cytotoxic T cell infiltration, polarization of tumor-associated macrophage, and lower tumor proliferation were observed in ICI/EVs-treated mice. The developed ICI/EVs showed promise in immunotherapeutic management of glioma. Ā© 2024 The Authors.
- Cancer Research,
- Endocrinology and Physiology
Estrogen signaling suppresses tumor-associated tissue eosinophilia to promote breast tumor growth.
In Science Advances on 27 September 2024 by Artham, S., Juras, P. K., et al.
Estrogens regulate eosinophilia in asthma and other inflammatory diseases. Further, peripheral eosinophilia and tumor-associated tissue eosinophilia (TATE) predicts a better response to immune checkpoint blockade (ICB) in breast cancer. However, how and if estrogens affect eosinophil biology in tumors and how this influences ICB efficacy has not been determined. Here, we report that estrogens decrease the number of peripheral eosinophils and TATE, and this contributes to increased tumor growth in validated murine models of breast cancer and melanoma. Moreover, estrogen signaling in healthy female mice also suppressed peripheral eosinophil prevalence by decreasing the proliferation and survival of maturing eosinophils. Inhibiting estrogen receptor (ER) signaling decreased tumor growth in an eosinophil-dependent manner. Further, the efficacy of ICBs was increased when administered in combination with anti-estrogens. These findings highlight the importance of ER signaling as a regulator of eosinophil biology and TATE and highlight the potential near-term clinical application of ER modulators to increase ICB efficacy in multiple tumor types.
- Mus musculus (House mouse),
- Cancer Research
Cancer therapy via neoepitope-specific monoclonal antibody cocktails
Preprint on BioRxiv : the Preprint Server for Biology on 6 August 2024 by Hartman, C. J., Mohamed, A. O., et al.
ABSTRACT Background Cellular heterogeneity presents a significant challenge to cancer treatment. Antibody therapies targeting individual tumor-associated antigens can be extremely effective but are not suited for all patients and often fail against tumors with heterogeneous expression as tumor cells with low or no antigen expression escape targeting and develop resistance. Simultaneously targeting multiple tumor-specific proteins with multiple antibodies has the potential to overcome this barrier and improve efficacy, but relatively few widely expressed cancer-specific antigens are known. In contrast, neoepitopes, which arise from mutations unique to tumor cells, are considerably more abundant. However, since neoepitopes are not commonly shared between individuals, a patient-customized approach is necessary and motivates efforts to develop an efficient means to identify suitable target mutations and isolate neoepitope-specific monoclonal antibodies. Methods Here, focusing on the latter goal, we use directed evolution in yeast and phage display systems to engineer antibodies from non-immune, human antibody fragment libraries that are specific for neoepitopes previously reported in the B16F10 melanoma model. Results We demonstrate proof-of-concept for a pipeline that supports rapid isolation and functional enhancement of multiple neoepitope peptide-targeted monoclonal antibodies and demonstrate their robust binding to B16F10 cells and potent effector functions in vitro . These antibodies were combined and evaluated in vivo for anti-cancer activity in tumor-bearing mice, where they suppressed B16F10 tumor growth and prolonged survival. Conclusions These findings emphasize the potential for clinical application of patient-customized antibody cocktails in the treatment of the many cancers poorly addressed by current therapies.
- Mus musculus (House mouse),
- Cancer Research
Anti-CTLA-4 treatment suppresses hepatocellular carcinoma growth through Th1-mediated cell cycle arrest and apoptosis.
In PLoS ONE on 6 August 2024 by Morihara, H., Yamada, T., et al.
Inhibiting the cytotoxic T-lymphocyte-associated protein-4 (CTLA-4)-mediated immune checkpoint system using an anti-CTLA-4 antibody (Ab) can suppress the growth of various cancers, but the detailed mechanisms are unclear. In this study, we established a monoclonal hepatocellular carcinoma cell line (Hepa1-6 #12) and analyzed the mechanisms associated with anti-CTLA-4 Ab treatment. Depletion of CD4+ T cells, but not CD8+ T cells, prevented anti-CTLA-4 Ab-mediated anti-tumor effects, suggesting dependence on CD4+ T cells. Anti-CTLA-4 Ab treatment resulted in recruitment of interferon-gamma (IFN-g)-producing CD4+ T cells, called T-helper 1 (Th1), into tumors, and neutralization of IFN-g abrogated the anti-tumor effects. Moreover, tumor growth suppression did not require major histocompatibility complex (MHC)-I or MHC-II expression on cancer cells. In vitro studies showed that IFN-g can induce cell cycle arrest and apoptosis in tumor cells. Taken together, these data demonstrate that anti-CTLA-4 Ab can exert its anti-tumor effects through Th1-mediated cell cycle arrest and apoptosis. Copyright: Ā© 2024 Morihara et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
- Mus musculus (House mouse),
- Immunology and Microbiology,
- IHC,
- FC/FACS
Gasdermin-E-mediated pyroptosis drives immune checkpoint inhibitor-associated myocarditis via cGAS-STING activation.
In Nature Communications on 5 August 2024 by Sun, S. J., Jiao, X. D., et al.
Immune checkpoint inhibitor (ICI)-induced myocarditis involves intensive immune/inflammation activation; however, its molecular basis is unclear. Here, we show that gasdermin-E (GSDME), a gasdermin family member, drives ICI-induced myocarditis. Pyroptosis mediated by GSDME, but not the canonical GSDMD, is activated in myocardial tissue of mice and cancer patients with ICI-induced myocarditis. Deficiency of GSDME in male mice alleviates ICI-induced cardiac infiltration of T cells, macrophages, and monocytes, as well as mitochondrial damage and inflammation. Restoration of GSDME expression specifically in cardiomyocytes, rather than myeloid cells, in GSDME-deficient mice reproduces ICI-induced myocarditis. Mechanistically, quantitative proteomics reveal that GSDME-dependent pyroptosis promotes cell death and mitochondrial DNA release, which in turn activates cGAS-STING signaling, triggering a robust interferon response and myocardial immune/inflammation activation. Pharmacological blockade of GSDME attenuates ICI-induced myocarditis and improves long-term survival in mice. Our findings may advance the understanding of ICI-induced myocarditis and suggest that targeting the GSDME-cGAS-STING-interferon axis may help prevent and manage ICI-associated myocarditis. Ā© 2024. The Author(s).
- Mus musculus (House mouse),
- Cancer Research
177Lu-SN201 nanoparticle shows superior anti-tumor efficacy over conventional cancer drugs in 4T1 orthotopic model.
In Investigational New Drugs on 1 August 2024 by Lekmeechai, S., Pietras, K., et al.
In the current in-vivo study we demonstrate the potential of the radiolabeled nanoparticle 177Lu-SN201 as an effective anticancer treatment, as evidenced by significantly prolonged survival and reduced tumor burden in the aggressive, triple negative 4T1 murine breast cancer model. We show with high statistical significance that 177Lu-SN201 is superior at suppressing the tumor growth not only compared to vehicle but also to the commonly used cancer drugs paclitaxel, niraparib, carboplatin, and the combination of the immune checkpoint inhibitors anti PD-1 and anti-CTLA-4. The dosing of the standard drugs were based on examples in the literature where good effects have been seen in various mouse models. The treatment is reasonably well-tolerated, as indicated by clinical chemistry of liver and renal function through the measurement of glutamate pyruvate alanine aminotransferase, alanine amino transferase, blood urea nitrogen, and creatinine levels in plasma samples, despite some weight loss. Overall, 177Lu-SN201 presents as a promising therapeutic candidate for cancer treatment. Ā© 2024. The Author(s).
- Endocrinology and Physiology
Oral administration of CXCL12-expressing Limosilactobacillus reuteri improves colitis by local immunomodulatory actions in preclinical models.
In American Journal of Physiology - Gastrointestinal and Liver Physiology on 1 August 2024 by Ćhnstedt, E., DoƱas, C., et al.
Treatments of colitis, inflammation of the intestine, rely on induction of immune suppression associated with systemic adverse events, including recurrent infections. This treatment strategy is specifically problematic in the increasing population of patients with cancer with immune checkpoint inhibitor (ICI)-induced colitis, as immune suppression also interferes with the ICI-treatment response. Thus, there is a need for local-acting treatments that reduce inflammation and enhance intestinal healing. Here, we investigated the effect and safety of bacterial delivery of short-lived immunomodulating chemokines to the inflamed intestine in mice with colitis. Colitis was induced by dextran sulfate sodium (DSS) alone or in combination with ICI (anti-PD1 and anti-CTLA-4), and Limosilactobacillus reuteri R2LC (L. reuteri R2LC) genetically modified to express the chemokine CXCL12-1Ī± (R2LC_CXCL12, emilimogene sigulactibac) was given perorally. In addition, the pharmacology and safety of the formulated drug candidate, ILP100-Oral, were evaluated in rabbits. Peroral CXCL12-producing L. reuteri R2LC significantly improved colitis symptoms already after 2 days in mice with overt DSS and ICI-induced colitis, which in benchmarking experiments was demonstrated to be superior to treatments with anti-TNF-Ī±, anti-Ī±4Ī²7, and corticosteroids. The mechanism of action involved chemokine delivery to Peyer's patches (PPs), confirmed by local CXCR4 signaling, and increased numbers of colonic, regulatory immune cells expressing IL-10 and TGF-Ī²1. No systemic exposure or engraftment could be detected in mice, and product feasibility, pharmacology, and safety were confirmed in rabbits. In conclusion, peroral CXCL12-producing L. reuteri R2LC efficiently ameliorates colitis, enhances mucosal healing, and has a favorable safety profile.NEW & NOTEWORTHY Colitis symptoms are efficiently reduced by peroral administration of probiotic bacteria genetically modified to deliver CXCL12 locally to the inflamed intestine in several mouse models.
- Mus musculus (House mouse),
- Immunology and Microbiology
Post-immunotherapy CTLA-4 Ig treatment improves antitumor efficacy.
In Proceedings of the National Academy of Sciences of the United States of America on 2 July 2024 by Mok, S., AÄaƧ ĆobanoÄlu, D., et al.
Immune checkpoint therapies (ICT) improve overall survival of patients with cancer but may cause immune-related adverse events (irAEs) such as myocarditis. Cytotoxic T lymphocyte-associated antigen 4 immunoglobulin fusion protein (CTLA-4 Ig), an inhibitor of T cell costimulation through CD28, reverses irAEs in animal models. However, concerns exist about potentially compromising antitumor response of ICT. In mouse tumor models, we administered CTLA-4 Ig 1) concomitantly with ICT or 2) after ICT completion. Concomitant treatment reduced antitumor efficacy, while post-ICT administration improved efficacy without affecting frequency and function of CD8 T cells. The improved response was independent of the ICT used, whether CTLA-4 or PD-1 blockade. The frequency of Tregs was significantly decreased with CTLA-4 Ig. The resulting increased CD8/Treg ratio potentially underlies the enhanced efficacy of ICT followed by CTLA-4 Ig. This paradoxical mechanism shows that a CTLA-4 Ig regimen shown to reduce irAE severity does not compromise antitumor efficacy.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
JAK inhibition enhances checkpoint blockade immunotherapy in patients with Hodgkin lymphoma.
In Science on 21 June 2024 by Zak, J., Pratumchai, I., et al.
Unleashing antitumor T cell activity by checkpoint inhibitor immunotherapy is effective in cancer patients, but clinical responses are limited. Cytokine signaling through the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway correlates with checkpoint immunotherapy resistance. We report a phase I clinical trial of the JAK inhibitor ruxolitinib with anti-PD-1 antibody nivolumab in Hodgkin lymphoma patients relapsed or refractory following checkpoint inhibitor immunotherapy. The combination yielded a best overall response rate of 53% (10/19). Ruxolitinib significantly reduced neutrophil-to-lymphocyte ratios and percentages of myeloid suppressor cells but increased numbers of cytokine-producing T cells. Ruxolitinib rescued the function of exhausted T cells and enhanced the efficacy of immune checkpoint blockade in preclinical solid tumor and lymphoma models. This synergy was characterized by a switch from suppressive to immunostimulatory myeloid cells, which enhanced T cell division.
