InVivoMAb anti-mouse NK1.1

Catalog #BE0036
Product Citations:
290
Clone:
PK136
Reactivities:
Mouse

$172.00 - $4,494.00

Choose an Option...
  • 100 mg - $4,494.00
  • 50 mg - $3,175.00
  • 25 mg - $2,109.00
  • 5 mg - $630.00
  • 1 mg - $172.00
  • Custom Amount (Quotes Only)
In stock
Only %1 left

Product Details

The PK136 monoclonal antibody reacts with mouse NK1.1 also known as CD161b/CD161c, KLRB1, NKR-P1A and Ly-55. NK1.1 is a type II integral membrane glycoprotein with a C-type lectin domain and is encoded by the Klrb1c/NKR-P1C gene. NK1.1 plays roles in NK cell activation and differentiation, IFN-γ production, cytotoxic granule release, and is thought to be involved in the generation of Th2 cells. NK1.1 is predominantly expressed as a disulfide-linked homodimer on NK cells however, it is also expressed on NK-T cells, a rare population of T lymphocytes. NK 1.1 is only expressed by C57BL/6, FVB/N, and NZB strains of mice and not AKR, BALB/c, CBA/J, C3H, DBA/1, DBA/2, NOD, SJL, and 129 strains.

Specifications

Isotype Mouse IgG2a,Ā Īŗ
Recommended Isotype Control(s) InVivoMAb mouse IgG2a 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 Mouse spleen and bone marrow cells enriched for NK1+ cells
Reported Applications in vivo NK cell depletion
Flow cytometry
Formulation PBS, pH 7.0
Contains no stabilizers or preservatives
Endotoxin <2EU/mg (<0.002EU/μg)
Determined by LAL gel clotting assay
Purity >95%
Determined by SDS-PAGE
Sterility 0.2 µm filtration
Production Purified from cell culture supernatant in an animal-free facility
Purification Protein A
RRID AB_1107737
Molecular Weight 150 kDa
Storage The antibody solution should be stored at the stock concentration at 4°C. Do not freeze.

Additional Formats

in vivo NK cell depletion
Glasner, A., et al. (2018). "NKp46 Receptor-Mediated Interferon-gamma Production by Natural Killer Cells Increases Fibronectin 1 to Alter Tumor Architecture and Control Metastasis" Immunity 48(1): 107-119 e104. PubMed

Natural killer (NK) cells are innate lymphoid cells, and their presence within human tumors correlates with better prognosis. However, the mechanisms by which NK cells control tumors in vivo are unclear. Here, we used reflectance confocal microscopy (RCM) imaging in humans and in mice to visualize tumor architecture in vivo. We demonstrated that signaling via the NK cell receptor NKp46 (human) and Ncr1 (mouse) induced interferon-gamma (IFN-gamma) secretion from intratumoral NK cells. NKp46- and Ncr1-mediated IFN-gamma production led to the increased expression of the extracellular matrix protein fibronectin 1 (FN1) in the tumors, which altered primary tumor architecture and resulted in decreased metastases formation. Injection of IFN-gamma into tumor-bearing mice or transgenic overexpression of Ncr1 in NK cells in mice resulted in decreased metastasis formation. Thus, we have defined a mechanism of NK cell-mediated control of metastases in vivo that may help develop NK cell-dependent cancer therapies.

in vivo NK cell depletion
Burrack, K. S., et al. (2018). "Interleukin-15 Complex Treatment Protects Mice from Cerebral Malaria by Inducing Interleukin-10-Producing Natural Killer Cells" Immunity 48(4): 760-772 e764. PubMed

Cerebral malaria is a deadly complication of Plasmodium infection and involves blood brain barrier (BBB) disruption following infiltration of white blood cells. During experimental cerebral malaria (ECM), mice inoculated with Plasmodium berghei ANKA-infected red blood cells develop a fatal CM-like disease caused by CD8(+) T cell-mediated pathology. We found that treatment with interleukin-15 complex (IL-15C) prevented ECM, whereas IL-2C treatment had no effect. IL-15C-expanded natural killer (NK) cells were necessary and sufficient for protection against ECM. IL-15C treatment also decreased CD8(+) T cell activation in the brain and prevented BBB breakdown without influencing parasite load. IL-15C induced NK cells to express IL-10, which was required for IL-15C-mediated protection against ECM. Finally, we show that ALT-803, a modified human IL-15C, mediates similar induction of IL-10 in NK cells and protection against ECM. These data identify a regulatory role for cytokine-stimulated NK cells in the prevention of a pathogenic immune response.

in vivo NK 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 NK cell depletion, Flow Cytometry
Ludigs, K., et al. (2016). "NLRC5 shields T lymphocytes from NK-cell-mediated elimination under inflammatory conditions" Nat Commun 7: 10554. PubMed

NLRC5 is a transcriptional regulator of MHC class I (MHCI), which maintains high MHCI expression particularly in T cells. Recent evidence highlights an important NK-T-cell crosstalk, raising the question on whether NLRC5 specifically modulates this interaction. Here we show that NK cells from Nlrc5-deficient mice exhibit moderate alterations in inhibitory receptor expression and responsiveness. Interestingly, NLRC5 expression in T cells is required to protect them from NK-cell-mediated elimination upon inflammation. Using T-cell-specific Nlrc5-deficient mice, we show that NK cells surprisingly break tolerance even towards ā€˜self’ Nlrc5-deficient T cells under inflammatory conditions. Furthermore, during chronic LCMV infection, the total CD8(+) T-cell population is severely decreased in these mice, a phenotype reverted by NK-cell depletion. These findings strongly suggest that endogenous T cells with low MHCI expression become NK-cell targets, having thus important implications for T-cell responses in naturally or therapeutically induced inflammatory conditions.

in vivo NK cell depletion
Ghasemi, R., et al. (2016). "Selective targeting of IL-2 to NKG2D bearing cells for improved immunotherapy" Nat Commun 7: 12878. PubMed

Despite over 20 years of clinical use, IL-2 has not fulfilled expectations as a safe and effective form of tumour immunotherapy. Expression of the high affinity IL-2Ralpha chain on regulatory T cells mitigates the anti-tumour immune response and its expression on vascular endothelium is responsible for life threatening complications such as diffuse capillary leak and pulmonary oedema. Here we describe the development of a recombinant fusion protein comprised of a cowpox virus encoded NKG2D binding protein (OMCP) and a mutated form of IL-2 with poor affinity for IL-2Ralpha. This fusion protein (OMCP-mutIL-2) potently and selectively activates IL-2 signalling only on NKG2D-bearing cells, such as natural killer (NK) cells, without broadly activating IL-2Ralpha-bearing cells. OMCP-mutIL-2 provides superior tumour control in several mouse models of malignancy and is not limited by mouse strain-specific variability of NK function. In addition, OMCP-mutIL-2 lacks the toxicity and vascular complications associated with parental wild-type IL-2.

in vivo NK cell depletion, Flow Cytometry
Maltez, V. I., et al. (2015). "Inflammasomes Coordinate Pyroptosis and Natural Killer Cell Cytotoxicity to Clear Infection by a Ubiquitous Environmental Bacterium" Immunity 43(5): 987-997. PubMed

Defective neutrophils in patients with chronic granulomatous disease (CGD) cause susceptibility to extracellular and intracellular infections. Microbes must first be ejected from intracellular niches to expose them to neutrophil attack, so we hypothesized that inflammasomes detect certain CGD pathogens upstream of neutrophil killing. Here, we identified one such ubiquitous environmental bacterium, Chromobacterium violaceum, whose extreme virulence was fully counteracted by the NLRC4 inflammasome. Caspase-1 protected via two parallel pathways that eliminated intracellular replication niches. Pyroptosis was the primary bacterial clearance mechanism in the spleen, but both pyroptosis and interleukin-18 (IL-18)-driven natural killer (NK) cell responses were required for liver defense. NK cells cleared hepatocyte replication niches via perforin-dependent cytotoxicity, whereas interferon-gamma was not required. These insights suggested a therapeutic approach: exogenous IL-18 restored perforin-dependent cytotoxicity during infection by the inflammasome-evasive bacterium Listeria monocytogenes. Therefore, inflammasomes can trigger complementary programmed cell death mechanisms, directing sterilizing immunity against intracellular bacterial pathogens.

in vivo NK cell depletion, Flow Cytometry
Wensveen, F. M., et al. (2015). "NK cells link obesity-induced adipose stress to inflammation and insulin resistance" Nat Immunol 16(4): 376-385. PubMed

An important cause of obesity-induced insulin resistance is chronic systemic inflammation originating in visceral adipose tissue (VAT). VAT inflammation is associated with the accumulation of proinflammatory macrophages in adipose tissue, but the immunological signals that trigger their accumulation remain unknown. We found that a phenotypically distinct population of tissue-resident natural killer (NK) cells represented a crucial link between obesity-induced adipose stress and VAT inflammation. Obesity drove the upregulation of ligands of the NK cell-activating receptor NCR1 on adipocytes; this stimulated NK cell proliferation and interferon-gamma (IFN-gamma) production, which in turn triggered the differentiation of proinflammatory macrophages and promoted insulin resistance. Deficiency of NK cells, NCR1 or IFN-gamma prevented the accumulation of proinflammatory macrophages in VAT and greatly ameliorated insulin sensitivity. Thus NK cells are key regulators of macrophage polarization and insulin resistance in response to obesity-induced adipocyte stress.

in vivo NK 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 NK cell depletion
Mitchell, D. A., et al. (2015). "Tetanus toxoid and CCL3 improve dendritic cell vaccines in mice and glioblastoma patients" Nature 519(7543): 366-369. PubMed

After stimulation, dendritic cells (DCs) mature and migrate to draining lymph nodes to induce immune responses. As such, autologous DCs generated ex vivo have been pulsed with tumour antigens and injected back into patients as immunotherapy. While DC vaccines have shown limited promise in the treatment of patients with advanced cancers including glioblastoma, the factors dictating DC vaccine efficacy remain poorly understood. Here we show that pre-conditioning the vaccine site with a potent recall antigen such as tetanus/diphtheria (Td) toxoid can significantly improve the lymph node homing and efficacy of tumour-antigen-specific DCs. To assess the effect of vaccine site pre-conditioning in humans, we randomized patients with glioblastoma to pre-conditioning with either mature DCs or Td unilaterally before bilateral vaccination with DCs pulsed with Cytomegalovirus phosphoprotein 65 (pp65) RNA. We and other laboratories have shown that pp65 is expressed in more than 90% of glioblastoma specimens but not in surrounding normal brain, providing an unparalleled opportunity to subvert this viral protein as a tumour-specific target. Patients given Td had enhanced DC migration bilaterally and significantly improved survival. In mice, Td pre-conditioning also enhanced bilateral DC migration and suppressed tumour growth in a manner dependent on the chemokine CCL3. Our clinical studies and corroborating investigations in mice suggest that pre-conditioning with a potent recall antigen may represent a viable strategy to improve anti-tumour immunotherapy.

in vivo NK cell depletion, Flow Cytometry
Walsh, K. B., et al. (2014). "Animal model of respiratory syncytial virus: CD8+ T cells cause a cytokine storm that is chemically tractable by sphingosine-1-phosphate 1 receptor agonist therapy" J Virol 88(11): 6281-6293. PubMed

The cytokine storm is an intensified, dysregulated, tissue-injurious inflammatory response driven by cytokine and immune cell components. The cytokine storm during influenza virus infection, whereby the amplified innate immune response is primarily responsible for pulmonary damage, has been well characterized. Now we describe a novel event where virus-specific T cells induce a cytokine storm. The paramyxovirus pneumonia virus of mice (PVM) is a model of human respiratory syncytial virus (hRSV). Unexpectedly, when C57BL/6 mice were infected with PVM, the innate inflammatory response was undetectable until day 5 postinfection, at which time CD8(+) T cells infiltrated into the lung, initiating a cytokine storm by their production of gamma interferon (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha). Administration of an immunomodulatory sphingosine-1-phosphate (S1P) receptor 1 (S1P1R) agonist significantly inhibited PVM-elicited cytokine storm by blunting the PVM-specific CD8(+) T cell response, resulting in diminished pulmonary disease and enhanced survival. IMPORTANCE: A dysregulated overly exuberant immune response, termed a ā€œcytokine storm,ā€ accompanies virus-induced acute respiratory diseases (VARV), is primarily responsible for the accompanying high morbidity and mortality, and can be controlled therapeutically in influenza virus infection of mice and ferrets by administration of sphingosine-1-phosphate 1 receptor (S1P1R) agonists. Here, two novel findings are recorded. First, in contrast to influenza infection, where the cytokine storm is initiated early by the innate immune system, for pneumonia virus of mice (PVM), a model of RSV, the cytokine storm is initiated late in infection by the adaptive immune response: specifically, by virus-specific CD8 T cells via their release of IFN-gamma and TNF-alpha. Blockading these cytokines with neutralizing antibodies blunts the cytokine storm and protects the host. Second, PVM infection is controlled by administration of an S1P1R agonist.

in vivo NK cell depletion, Flow Cytometry
Uddin, M. N., et al. (2014). "TNF-alpha-dependent hematopoiesis following Bcl11b deletion in T cells restricts metastatic melanoma" J Immunol 192(4): 1946-1953. PubMed

Using several tumor models, we demonstrate that mice deficient in Bcl11b in T cells, although having reduced numbers of T cells in the peripheral lymphoid organs, developed significantly less tumors compared with wild-type mice. Bcl11b(-/-) CD4(+) T cells, with elevated TNF-alpha levels, but not the Bcl11b(-/-) CD8(+) T cells, were required for the reduced tumor burden, as were NK1.1(+) cells, found in increased numbers in Bcl11b(F/F)/CD4-Cre mice. Among NK1.1(+) cells, the NK cell population was predominant in number and was the only population displaying elevated granzyme B levels and increased degranulation, although not increased proliferation. Although the number of myeloid-derived suppressor cells was increased in the lungs with metastatic tumors of Bcl11b(F/F)/CD4-Cre mice, their arginase-1 levels were severely reduced. The increase in NK cell and myeloid-derived suppressor cell numbers was associated with increased bone marrow and splenic hematopoiesis. Finally, the reduced tumor burden, increased numbers of NK cells in the lung, and increased hematopoiesis in Bcl11b(F/F)/CD4-Cre mice were all dependent on TNF-alpha. Moreover, TNF-alpha treatment of wild-type mice also reduced the tumor burden and increased hematopoiesis and the numbers and activity of NK cells in the lung. In vitro treatment with TNF-alpha of lineage-negative hematopoietic progenitors increased NK and myeloid differentiation, further supporting a role of TNF-alpha in promoting hematopoiesis. These studies reveal a novel role for TNF-alpha in the antitumor immune response, specifically in stimulating hematopoiesis and increasing the numbers and activity of NK cells.

in vivo NK cell depletion
Guo, Z., et al. (2014). "PD-1 blockade and OX40 triggering synergistically protects against tumor growth in a murine model of ovarian cancer" PLoS One 9(2): e89350. PubMed

The co-inhibitory receptor Programmed Death-1 (PD-1) curtails immune responses and prevent autoimmunity, however, tumors exploit this pathway to escape from immune destruction. The co-stimulatory receptor OX40 is upregulated on T cells following activation and increases their clonal expansion, survival and cytokine production when engaged. Although antagonistic anti-PD-1 or agonistic anti-OX40 antibodies can promote the rejection of several murine tumors, some poorly immunogenic tumors were refractory to this treatment. In the present study, we evaluated the antitumor effects and mechanisms of combinatorial PD-1 blockade and OX40 triggering in a murine ID8 ovarian cancer model. Although individual anti-PD-1 or OX40 mAb treatment was ineffective in tumor protection against 10-day established ID8 tumor, combined anti-PD-1/OX40 mAb treatment markedly inhibited tumor outgrowth with 60% of mice tumor free 90 days after tumor inoculation. Tumor protection was associated with a systemic immune response with memory and antigen specificity and required CD4(+) cells and CD8(+) T cells. The anti-PD-1/OX40 mAb treatment increased CD4(+) and CD8(+) cells and decreased immunosuppressive CD4(+)FoxP3(+) regulatory T (Treg) cells and CD11b(+)Gr-1(+) myeloid suppressor cells (MDSC), giving rise to significantly higher ratios of both effector CD4(+) and CD8(+) cells to Treg and MDSC in peritoneal cavity; Quantitative RT-PCR data further demonstrated the induction of a local immunostimulatory milieu by anti-PD-1/OX40 mAb treatment. The splenic CD8(+) T cells from combined mAb treated mice produced high levels of IFN-gamma upon tumor antigen stimulation and exhibited antigen-specific cytolytic activity. To our knowledge, this is the first study testing the antitumor effects of combined anti-PD-1/OX40 mAb in a murine ovarian cancer model, and our results provide a rationale for clinical trials evaluating ovarian cancer immunotherapy using this combination of mAb.

in vivo NK cell depletion
Hervieu, A., et al. (2013). "Dacarbazine-mediated upregulation of NKG2D ligands on tumor cells activates NK and CD8 T cells and restrains melanoma growth" J Invest Dermatol 133(2): 499-508. PubMed

Dacarbazine (DTIC) is a cytotoxic drug widely used for melanoma treatment. However, the putative contribution of anticancer immune responses in the efficacy of DTIC has not been evaluated. By testing how DTIC affects host immune responses to cancer in a mouse model of melanoma, we unexpectedly found that both natural killer (NK) and CD8(+) T cells were indispensable for DTIC therapeutic effect. Although DTIC did not directly affect immune cells, it triggered the upregulation of NKG2D ligands on tumor cells, leading to NK cell activation and IFNgamma secretion in mice and humans. NK cell-derived IFNgamma subsequently favored upregulation of major histocompatibility complex class I molecules on tumor cells, rendering them sensitive to cytotoxic CD8(+) T cells. Accordingly, DTIC markedly enhanced cytotoxic T lymphocyte antigen 4 inhibition efficacy in vivo in an NK-dependent manner. These results underscore the immunogenic properties of DTIC and provide a rationale to combine DTIC with immunotherapeutic agents that relieve immunosuppression in vivo.

in vivo NK cell depletion
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€{ā€œ2″:14851,ā€3ā€:{ā€œ1″:0},ā€4ā€:{ā€œ1″:2,ā€2″:16777215},ā€12″:0,ā€14ā€:{ā€œ1″:2,ā€2″:1521491},ā€15″:ā€Roboto, sans-serifā€,ā€16″: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 NK cell depletion
Richter, K., et al. (2013). "Macrophage and T cell produced IL-10 promotes viral chronicity" PLoS Pathog 9(11): e1003735. PubMed

Chronic viral infections lead to CD8(+) T cell exhaustion, characterized by impaired cytokine secretion. Presence of the immune-regulatory cytokine IL-10 promotes chronicity of Lymphocytic Choriomeningitis Virus (LCMV) Clone 13 infection, while absence of IL-10/IL-10R signaling early during infection results in viral clearance and higher percentages and numbers of antiviral, cytokine producing T cells. IL-10 is produced by several cell types during LCMV infection but it is currently unclear which cellular sources are responsible for induction of viral chronicity. Here, we demonstrate that although dendritic cells produce IL-10 and overall IL-10 mRNA levels decrease significantly in absence of CD11c(+) cells, absence of IL-10 produced by CD11c(+) cells failed to improve the LCMV-specific T cell response and control of LCMV infection. Similarly, NK cell specific IL-10 deficiency had no positive impact on the LCMV-specific T cell response or viral control, even though high percentages of NK cells produced IL-10 at early time points after infection. Interestingly, we found markedly improved T cell responses and clearance of normally chronic LCMV Clone 13 infection when either myeloid cells or T cells lacked IL-10 production and mice depleted of monocytes/macrophages or CD4(+) T cells exhibited reduced overall levels of IL-10 mRNA. These data suggest that the decision whether LCMV infection becomes chronic or can be cleared critically depends on early CD4(+) T cell and monocyte/macrophage produced IL-10.

in vivo NK cell depletion, Flow Cytometry
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 NK cell depletion
Ellermeier, J., et al. (2013). "Therapeutic efficacy of bifunctional siRNA combining TGF-beta1 silencing with RIG-I activation in pancreatic cancer" Cancer Res 73(6): 1709-1720. PubMed

Deregulated TGF-beta signaling in pancreatic cancer promotes tumor growth, invasion, metastasis, and a potent immunosuppressive network. A strategy for disrupting this tumor-promoting pathway is silencing TGF-beta by siRNA. By introducing a triphosphate group at the 5′ end of siRNA (ppp-siRNA), gene silencing can be combined with immune activation via the cytosolic helicase retinoic acid-inducible gene I (RIG-I), a ubiquitously expressed receptor recognizing viral RNA. We validated RIG-I as a therapeutic target by showing that activation of RIG-I in pancreatic carcinoma cells induced IRF-3 phosphorylation, production of type I IFN, the chemokine CXCL10, as well as caspase-9-mediated tumor cell apoptosis. Next, we generated a bifunctional ppp-siRNA that combines RIG-I activation with gene silencing of TGF-beta1 (ppp-TGF-beta) and studied its therapeutic efficacy in the orthotopic Panc02 mouse model of pancreatic cancer. Intravenous injection of ppp-TGF-beta reduced systemic and tumor-associated TGF-beta levels. In addition, it induced high levels of type I IFN and CXCL10 in serum and tumor tissue, systemic immune cell activation, and profound tumor cell apoptosis in vivo. Treatment of mice with established tumors with ppp-TGF-beta significantly prolonged survival as compared with ppp-RNA or TGF-beta siRNA alone. Furthermore, we observed the recruitment of activated CD8(+) T cells to the tumor and a reduced frequency of CD11b(+) Gr-1(+) myeloid cells. Therapeutic efficacy was dependent on CD8(+) T cells, whereas natural killer cells were dispensable. In conclusion, combing TGF-beta gene silencing with RIG-I signaling confers potent antitumor efficacy against pancreatic cancer by breaking tumor-induced CD8(+) T cell suppression.

in vivo NK cell depletion, Flow Cytometry
Monticelli, L. A., et al. (2011). "Innate lymphoid cells promote lung-tissue homeostasis after infection with influenza virus" Nat Immunol 12(11): 1045-1054. PubMed

Innate lymphoid cells (ILCs), a heterogeneous cell population, are critical in orchestrating immunity and inflammation in the intestine, but whether ILCs influence immune responses or tissue homeostasis at other mucosal sites remains poorly characterized. Here we identify a population of lung-resident ILCs in mice and humans that expressed the alloantigen Thy-1 (CD90), interleukin 2 (IL-2) receptor a-chain (CD25), IL-7 receptor a-chain (CD127) and the IL-33 receptor subunit T1-ST2. Notably, mouse ILCs accumulated in the lung after infection with influenza virus, and depletion of ILCs resulted in loss of airway epithelial integrity, diminished lung function and impaired airway remodeling. These defects were restored by administration of the lung ILC product amphiregulin. Collectively, our results demonstrate a critical role for lung ILCs in restoring airway epithelial integrity and tissue homeostasis after infection with influenza virus.

    • Cancer Research
    • ,
    Upregulation of Lactobacillus spp. in gut microbiota as a novel mechanism for environmental eustress-induced anti-pancreatic cancer effects.

    In Gut Microbes on 1 December 2025 by Liang, Y., Du, M., et al.

    Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy with limited effective treatment options. Emerging evidence links enriched environment (EE)-induced eustress to PDAC inhibition. However, the underlying mechanisms remain unclear. In this study, we explored the role of gut microbiota in PDAC-suppressive effects of EE. We demonstrated that depletion of gut microbiota with antibiotics abolished EE-induced tumor suppression, while fecal microbiota transplantation (FMT) from EE mice significantly inhibited tumor growth in both subcutaneous and orthotopic PDAC models housed in standard environment. 16S rRNA sequencing revealed that EE enhanced gut microbiota diversity and selectively enriched probiotic Lactobacillus, particularly L. reuteri. Treatment with L. reuteri significantly suppressed PDAC tumor growth and increased natural killer (NK) cell infiltration into the tumor microenvironment. Depletion of NK cells alleviated the anti-tumor effects of L. reuteri, underscoring the essential role of NK cell-mediated immunity in anti-tumor response. Clinical analysis of PDAC patients showed that higher fecal Lactobacillus abundance correlated with improved progression-free and overall survival, further supporting the therapeutic potential of L. reuteri in PDAC. Overall, this study identifies gut microbiota as a systemic regulator of PDAC under psychological stress. Supplementation of psychobiotic Lactobacillus may offer a novel therapeutic strategy for PDAC.

    • In Vivo
    • ,
    • Mus musculus (House mouse)
    • ,
    • Cancer Research
    • ,
    • Cell Biology
    • ,
    • Immunology and Microbiology
    Intratumoral Brevibacillus parabrevis enhances antitumor immunity by inhibiting NK cell ferroptosis in hepatocellular carcinoma.

    In Cell Death & Disease on 21 May 2025 by Pan, B., Zhang, X., et al.

    It is known that intestinal flora affects the number and function of NK cells through metabolites, thereby regulating the response of tumors to chemotherapy or immunotherapy. However, little is known about whether intratumoral bacteria are involved in NK cell-mediated antitumor immunity. In this study, 2bRAD-M analysis was performed on patient hepatocellular carcinoma and paired tissues to determine the composition of the intratumoral microbiota. Mass cytometry, flow cytometry, co-immunoprecipitation, immunoblotting, immunofluorescence, and DNA pull-down assays were used to evaluate the relationship between intratumoral bacteria, ferroptosis, and NK cell activity in Hu-SRC mice. Here, we found that the intratumoral B. parabrevis inhibited NK cell ferroptosis by promoting lipolysis into acetyl-CoA. Mechanistically, B. parabrevis catalyzed the acetylation of RORC, enhancing its binding to the NEDD4L promoter. NEDD4L induced ubiquitination of iron transporters SLC39A14, SLC39A8, and STEAP3. Functionally, B. parabrevis induced NK cells to differentiate into adaptability, cytotoxicity, and heat shock phenotypes, inhibiting the terminal phenotype and changing the tumor microenvironment from "cold" to "hot". In conclusion, B. parabrevis enhanced the antitumor response of NK cells by regulating post-translational modifications. Our study identified a new strategy for utilizing intratumor bacteria for clinical treatment. Ā© 2025. The Author(s).

    • Cancer Research
    RAC2 inhibition enhances tumor sensitivity to NK cell-mediated cytotoxicity.

    In Journal for Immunotherapy of Cancer on 2 May 2025 by Guo, H., Hu, J., et al.

    Natural killer (NK) cells are recognized for their ability to kill tumor cells for tumor control, but tumor cells often develop resistance to evade NK cell-mediated cytotoxicity. Identification of molecular mechanisms by which tumor cells evade from NK cell-mediated killing may offer novel therapeutic strategies for potentiating NK-based cancer immunotherapy. An in vitro tumor-NK cell co-culture system was employed to identify the most significantly altered genes in tumor cells following NK cell interaction. The cell death rate of tumor cells by NK cell exposure was quantified using flow cytometry. EL4 and HCT116 tumor models in C57BL/6, BALB/c-nu, and NOD/SCID mice were used for evaluating tumor growth differences induced by Rac2 knockdown or knockout. The cellular and molecular impact of Rac2 knockdown or knockout on the sensitivity of tumor cells to NK cell-mediated cytotoxicity was assessed using quantitative PCR, immunofluorescence, and mutation analysis. By screening expression levels of the Ras homology (Rho) GTPase family genes in tumor cells after co-culture with NK cells, we identified RAC2 as a key regulator of tumor cell resistance to NK cell-mediated cytotoxicity among the Rho GTPase family members. Furthermore, knockout of RAC2 in human colorectal cancer cells leads to increased tumor susceptibility to NK cell-mediated cytotoxicity in a xenograft tumor model. Mechanistically, the absence of RAC2 enhances tumor cell sensitivity to NK cell-mediated killing by facilitating cell-cell contact. These findings indicate that the inhibition of RAC2 in tumor cells substantially enhances their susceptibility to NK cell-mediated cytotoxicity, thereby providing a potential therapeutic target for optimizing NK cell therapy. Ā© Author(s) (or their employer(s)) 2025. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ Group.

    • Cancer Research
    • ,
    • Immunology and Microbiology
    Activating the CXCR3/CXCL10 pathway overrides tumor immune suppression by enhancing immune trafficking and effector cell priming in head and neck squamous cell carcinoma

    Preprint on BioRxiv : the Preprint Server for Biology on 28 April 2025 by Shinn, C. K., Saddawi-Konefka, R., et al.

    ABSTRACT The immune-suppressive nature of the tumor microenvironment (TME) has limited the impact of immune checkpoint blockade in many cancers, often by restricting the infiltration and activation of anti-tumoral CD8+ T, CD4+ T, and NK cells. Here, we utilized murine models of head and neck squamous cell carcinoma and demonstrated that intratumoral (IT) delivery of CXCL10 drives tumor elimination and inhibits recurrence. CD8+ T cells recruited to tumors display enhanced activation, increased tumor antigen specificity, and decreased markers of T cell exhaustion, indicating that CXCL10 not only directs cell migration, but also enhances T cell effector functions. Despite delivery of CXCL10 into tumors, CD8+ and CD4+ T cells also show enhanced presence and proliferation in tumor-draining lymph nodes (TdLNs), consistent with antigen presentation and trafficking of these cells between tumors and TdLNs. CXCL10 also stunts angiogenesis and lymphangiogenesis within the TME, which likely contributes to its antitumoral effects. Finally, enhanced tumor clearance was observed by combining IT CXCL10 and anti-PD-1. Together, these findings provide the rationale for the clinical evaluation of CXCL10 as a strategy to enhance the efficacy of immunotherapy. Graphical Abstract SUMMARY CXCL10 suppresses tumor growth and promotes immune memory by recruiting T and NK cells into the tumor microenvironment, promoting tumor-specific antigen recognition and effector functions, slowing T cell exhaustion, and inhibiting angiogenesis. CXCL10 directly and indirectly mobilizes an immune cell network that together supports an anti-tumoral microenvironment.

    • In Vivo
    • ,
    • Mus musculus (House mouse)
    • ,
    • Cancer Research
    • ,
    • Immunology and Microbiology
    In vivo armed macrophages curb liver metastasis through tumor-reactive T-cell rejuvenation.

    In Nature Communications on 11 April 2025 by Notaro, M., Borghetti, M., et al.

    Despite recent progress in cancer treatment, liver metastases persist as an unmet clinical need. Here, we show that arming liver and tumor-associated macrophages in vivo to co-express tumor antigens (TAs), IFNα, and IL-12 unleashes robust anti-tumor immune responses, leading to the regression of liver metastases. Mechanistically, in vivo armed macrophages expand tumor reactive CD8+ T cells, which acquire features of progenitor exhausted T cells and kill cancer cells independently of CD4+ T cell help. IFNα and IL-12 produced by armed macrophages reprogram antigen presenting cells and rewire cellular interactions, rescuing tumor reactive T cell functions. In vivo armed macrophages trigger anti-tumor immunity in distinct liver metastasis mouse models of colorectal cancer and melanoma, expressing either surrogate tumor antigens, naturally occurring neoantigens or tumor-associated antigens. Altogether, our findings support the translational potential of in vivo armed liver macrophages to expand and rejuvenate tumor reactive T cells for the treatment of liver metastases. © 2025. The Author(s).

    • Cancer Research
    • ,
    • Immunology and Microbiology
    ULBP2 Promotes Tumor Progression by Suppressing NKG2D-Mediated Anti-Tumor Immunity.

    In International Journal of Molecular Sciences on 24 March 2025 by Yamane, K., Yamaguchi, K., et al.

    UL-16 binding protein 2 (ULBP2), a human NKG2D ligand, has been identified as a poor prognostic factor in several cancers based on recent comprehensive analyses of immune-related genes using the Cancer Genome Atlas datasets. Despite its clinical significance, the functional role of ULBP2 in vivo remains largely unknown. In this study, we investigated the role of ULBP2 in modulating anti-tumor immunity using murine melanoma cell lines engineered to stably express surface-expressed or soluble ULBP2. Subcutaneous transplantation of ULBP2-expressing melanoma cells into syngeneic mice resulted in accelerated tumor growth, mediated by surface-expressed ULBP2, through the suppression of NKG2D-dependent immune responses. In vitro experiments revealed that sustained exposure to tumor-expressed ULBP2 reduced NKG2D expression and cytotoxic activity of splenocytes. In contrast, soluble ULBP2 did not significantly affect tumor growth or immune responses. These findings suggest that surface-expressed ULBP2 plays a pivotal role in tumor immune evasion and highlight its potential as a therapeutic target to enhance anti-tumor immunity.

    • Cancer Research
    • ,
    • Immunology and Microbiology
    Th1-poised naive CD4 T cell subpopulation reflects anti-tumor immunity and autoimmune disease.

    In Nature Communications on 25 February 2025 by Yoon, J. W., Kim, K. M., et al.

    NaĆÆve CD4 T cells are traditionally viewed as a quiescent, homogeneous, resting population, but emerging evidence reveals their heterogeneity, which can be crucial for understanding disease contexts and therapeutic outcomes. In this study, we identify distinct subpopulations within both murine and human naĆÆve CD4 T cells by single cell-RNA-sequencing (scRNA-seq), particularly focusing on a subpopulation that expresses super-high levels of interleukin-7 receptor (IL-7Rsup-hi), along with CD97, IL-18R, and Ly6C. This subpopulation, absent in the thymus and peripherally induced, exhibits type 1 helper T cell (Th1)-poised characteristics and contributes to the inhibition of cancer progression in B16F10 tumor-bearing mice. In humans, this IL-7Rsup-hi subpopulation expressing CD97 correlates with the responsiveness to anti-PD-1 therapy in cancer patients and the disease state of multiple sclerosis. By elucidating the heterogeneity of naive CD4 T cells and identifying a Th1-poised subpopulation capable of robust type 1 responses, we highlight the importance of this heterogeneity in inflammatory conditions for defining the disease states and predicting drug responsiveness. Ā© 2025. The Author(s).

    • Cancer Research
    • ,
    • Immunology and Microbiology
    A novel HVEM-Fc recombinant protein for lung cancer immunotherapy.

    In Journal of Experimental & Clinical Cancer Research : CR on 20 February 2025 by Yao, Y., Li, B., et al.

    The ubiquitously expressed transmembrane protein, Herpesvirus Entry Mediator (HVEM), functions as a molecular switch, capable of both activating and inhibiting the immune response depending on its interacting ligands. HVEM-Fc is a novel recombinant fusion protein with the potential to eradicate tumor cells. The anti-tumor efficacy of HVEM-Fc was evaluated in C57BL/6 mice-bearing lung cancer models: a syngeneic model and an orthotopic model of mouse lung cancer. Additionally, patient-derived organoids were employed in conjunction with T cell co-culture systems. To investigate the underlying mechanisms, a comprehensive array of techniques was utilized, including single-cell RNA sequencing, spatial transcriptomics, bulk RNA sequencing, and flow cytometry. Furthermore, the anti-tumor effects of HVEM-Fc in combination with Programmed Death-1 (PD-1) inhibitors were assessed. Finally, mouse immune cell depletion antibodies were used to elucidate the underlying mechanisms of action. In vivo, 1 mg/kg HVEM-Fc demonstrated effective inhibition of tumor growth and metastasis in C57BL/6 mice bearing lung cancer model and a KP orthotopic model of mouse lung cancer. Multi-omics analysis showed that HVEM-Fc induced an immune-stimulatory microenvironment. Notably, the combination of HVEM-Fc with a PD-1 inhibitor demonstrated the most potent inhibition of tumor cell growth. In vitro, HVEM-Fc was validated to eradicate tumor cells through the activation of T cells in both non-small cell lung cancer (NSCLC) organoids and T cell co-culture models. Our data demonstrate that HVEM-Fc exerts a strong signal that augments and prolongs T-cell activity in both murine models and human NSCLC organoid models. Moreover, the combination of HVEM-Fc with a PD-1 inhibitor yields the most effective anti-tumor outcomes. Ā© 2025. The Author(s).

    Nanrilkefusp alfa (SOT101), an IL-15 receptor βγ superagonist, as a single agent or with anti-PD-1 in patients with advanced cancers.

    In Cell Reports Medicine on 18 February 2025 by Champiat, S., Garralda, E., et al.

    Nanrilkefusp alfa (nanril; SOT101) is an interleukin (IL)-15 receptor βγ superagonist that stimulates natural killer (NK) and CD8+ T cells, thereby promoting an innate and adaptive anti-tumor inflammatory microenvironment in mouse tumor models either in monotherapy or combined with an anti-programmed cell death protein 1 (PD-1) antibody. In cynomolgus monkeys, a clinical schedule was identified, which translated into the design of a phase 1/1b clinical trial, AURELIO-03 (NCT04234113). In 51 patients with advanced/metastatic solid tumors, nanril increased the proportions of CD8+ T cells and NK cells in peripheral blood and tumors. It had a favorable safety profile when administered subcutaneously on days 1, 2, 8, and 9 of each 21-day cycle as monotherapy (0.25-15 μg/kg) or combined (1.5-12 μg/kg) with the anti-PD-1 pembrolizumab (200 mg). The most frequent treatment-emergent adverse events were pyrexia, injection site reactions, and chills. Furthermore, early clinical efficacy was observed, including in immune checkpoint blockade-resistant/refractory patients. Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.

    SMARCA4 regulates the NK-mediated killing of senescent cells.

    In Science Advances on 17 January 2025 by Reen, V., D'Ambrosio, M., et al.

    Induction of senescence by chemotherapeutic agents arrests cancer cells and activates immune surveillance responses to contribute to therapy outcomes. In this investigation, we searched for ways to enhance the NK-mediated elimination of senescent cells. We used a staggered screen approach, first identifying siRNAs potentiating the secretion of immunomodulatory cytokines to later test for their ability to enhance NK-mediated killing of senescent cells. We identified that genetic or pharmacological inhibition of SMARCA4 enhanced senescent cell elimination by NK cells. SMARCA4 expression is elevated during senescence and its inhibition derepresses repetitive elements, inducing the SASP via activation of cGAS/STING and MAVS/MDA5 pathways. Moreover, a PROTAC targeting SMARCA4 synergized with cisplatin to increase the infiltration of CD8 T cells and mature, activated NK cells in an immunocompetent model of ovarian cancer. Our results indicate that SMARCA4 inhibitors enhance NK-mediated surveillance of senescent cells and may represent senotherapeutic interventions for ovarian cancer.

    • Mus musculus (House mouse)
    • ,
    • Cancer Research
    • ,
    • Genetics
    • ,
    • Immunology and Microbiology
    Lipid nanoparticles deliver DNA-encoded biologics and induce potent protective immunity.

    In Molecular Cancer on 13 January 2025 by Chai, D., Wang, J., et al.

    Lipid nanoparticles (LNPs) for mRNA delivery have advanced significantly, but LNP-mediated DNA delivery still faces clinical challenges. This study compared various LNP formulations for delivering DNA-encoded biologics, assessing their expression efficacy and the protective immunity generated by LNP-encapsulated DNA in different models. The LNP formulation used in Moderna's Spikevax mRNA vaccine (LNP-M) demonstrated a stable nanoparticle structure, high expression efficiency, and low toxicity. Notably, a DNA vaccine encoding the spike protein, delivered via LNP-M, induced stronger antigen-specific antibody and T cell immune responses compared to electroporation. Single-cell RNA sequencing (scRNA-seq) analysis revealed that the LNP-M/pSpike vaccine enhanced CD80 activation signaling in CD8+ T cells, NK cells, macrophages, and DCs, while reducing the immunosuppressive signals. The enrichment of TCR and BCR by LNP-M/pSpike suggested an increase in immune response specificity and diversity. Additionally, LNP-M effectively delivered DNA-encoded antigens, such as mouse PD-L1 and p53R172H, or monoclonal antibodies targeting mouse PD1 and human p53R282W. This approach inhibited tumor growth or metastasis in several mouse models. The long-term anti-tumor effects of LNP-M-delivered anti-p53R282W antibody relied on memory CD8+ T cell responses and enhanced MHC-I signaling from APCs to CD8+ T cells. These results highlight LNP-M as a promising and effective platform for delivering DNA-based vaccines and cancer immunotherapies. Ā© 2025. The Author(s).

    • Mus musculus (House mouse)
    • ,
    • Cancer Research
    • ,
    • Immunology and Microbiology
    Remodelling of the immune landscape by IFNγ counteracts IFNγ-dependent tumour escape in mouse tumour models.

    In Nature Communications on 2 January 2025 by Lau, V. W. C., Mead, G. J., et al.

    Loss of IFNγ-sensitivity by tumours is thought to be a mechanism enabling evasion, but recent studies suggest that IFNγ-resistant tumours can be sensitised for immunotherapy, yet the underlying mechanism remains unclear. Here, we show that IFNγ receptor-deficient B16-F10 mouse melanoma tumours are controlled as efficiently as WT tumours despite their lower MHC class I expression. Mechanistically, IFNγ receptor deletion in B16-F10 tumours increases IFNγ availability, triggering a remodelling of the immune landscape characterised by inflammatory monocyte infiltration and the generation of 'mono-macs'. This altered myeloid compartment synergises with an increase in antigen-specific CD8+ T cells to promote anti-tumour immunity against IFNγ receptor-deficient tumours, with such an immune crosstalk observed around blood vessels. Importantly, analysis of transcriptomic datasets suggests that similar immune remodelling occurs in human tumours carrying mutations in the IFNγ pathway. Our work thus serves mechanistic insight for the crosstalk between tumour IFNγ resistance and anti-tumour immunity, and implicates this regulation for future cancer therapy. © 2024. The Author(s).

    • Immunology and Microbiology
    T cell-derived IFN-γ Suppresses T Follicular Helper Cell Differentiation and Antibody Responses

    Preprint on BioRxiv : the Preprint Server for Biology on 1 January 2025 by Sala, E., Nelli, M., et al.

    CD4 + T cells play a critical role in antiviral humoral and cellular immune responses. We have previously reported that subcutaneous lymphocytic choriomeningitis virus (s.c. LCMV) infection is characterized by a stark compartmentalization of CD4 + T cells, leading to strong T H 1 polarization but virtually absent T follicular helper (T FH ) cells, a key driver of humoral immunity. Here, we investigated the mechanisms responsible for this impaired T FH differentiation. We found that T-bet + cells induced by s.c. LCMV infection encompass a T H 1 subset expressing Granzyme-B (GzmB) and a Tcf-1 + subset that retains the potential for T FH differentiation without expressing mature T FH markers. Interestingly, IFN-γ blockade enables full differentiation of Tcf-1 + cells into T FH , formation of germinal centers and increased antibody production. Of note, the suppression of T FH cells by IFN-γ is not directly mediated through CD4 + T cells but rather involves another cell type, likely dendritic cells (DCs). Our study provides novel insights into the mechanisms directing early CD4 + T cell polarization and affecting humoral responses to viruses, laying a foundation for the development of effective vaccine strategies.

    • Immunology and Microbiology
    CD4 Co-Receptor Regulates Sex-Specific NK Cell Responses to AcuteToxoplasma gondiiInfection

    Preprint on BioRxiv : the Preprint Server for Biology on 12 December 2024 by Roy, T., Bernstein, L., et al.

    Immunity to Toxoplasma gondii ( T. gondii ) is sexually dimorphic in humans and mice, with females having higher morbidity and mortality during immune dysfunction and HIV-AIDS. The mechanisms underlying these sex differences are unclear. We investigated how a lack of CD4+ T cells (CD4 co-receptor KO) impacted T. gondii survival in mice. Female CD4 co-receptor KO mice succumbed to T. gondii much faster than males. To dissect why female CD4 co-receptor KO mice died faster, we tested their NK cell responses to acute T. gondii infection compared to males. Although in wild-type (WT) animals, both sexes had similar increases in total NK cells and IFNγ + NK cells, infected CD4 co-receptor KO female mice had 50% fewer IFNγ+ NK cells than infected WT female mice. Infected male CD4 co-receptor KO had a similar increase in IFNγ+ NK cells as WT male mice. Since CD4 co-receptor deficient mice still have functional helper T cells that are CD4āˆ’, we next tested survival and NK cell responses in female and male MHCII deficient (MHCIIKO) animals, which completely lack helper CD4+T cells. Surprisingly, survival, NK cell numbers, and IFNγ+ NK cells were not significantly different between WT or MHCIIKO female and male mice. These results suggest CD4 co-receptor expression is required for survival via optimal NK cell responses during acute T. gondii infection only in female mice and not in male mice. Our findings reveal an unappreciated sexual dimorphic role of CD4 co-receptor expression in regulating NK cell responses to acute T. gondii infection.

    • Mus musculus (House mouse)
    Potent antitumor activity of a designed interleukin-21 mimic

    Preprint on BioRxiv : the Preprint Server for Biology on 7 December 2024 by Chun, J., Lim, B. S., et al.

    Long-standing goals of cancer immunotherapy are to activate cytotoxic antitumor T cells across a broad range of affinities while dampening suppressive regulatory T (Treg) cell responses, but current approaches achieve these goals with limited success. Here, we report a de novo IL-21 mimic, 21h10, designed to have augmented stability and high signaling potency in both humans and mice. In multiple animal models and in ex vivo human melanoma patient derived organotypic tumor spheroids (PDOTS), 21h10 showed robust antitumor activity. 21h10 generates significantly prolonged STAT signaling in vivo compared with native IL-21, and has considerably stronger anti-tumor activity. Toxicities associated with systemic administration of 21h10 could be mitigated by TNFα blockade without compromising antitumor efficacy. In the tumor microenvironment, 21h10 induced highly cytotoxic antitumor T cells from clonotypes with a range of affinities for endogenous tumor antigens, robustly expanding low-affinity cytotoxic T cells and driving high expression of interferon-

    • Cancer Research
    Tumor stage-driven disruption of NK cell maturation in human and murine tumors.

    In IScience on 15 November 2024 by Russick, J., Torset, C., et al.

    Natural killer (NK) cells play a pivotal role against cancer, both by direct killing of malignant cells and by promoting adaptive immune response though cytokine and chemokine secretion. In the lung tumor microenvironment (TME), NK cells are scarce and dysfunctional. By conducting single-cell transcriptomic analysis of lung tumors, and exploring pseudotime, we uncovered that the intratumoral maturation trajectory of NK cells is disrupted in a tumor stage-dependent manner, ultimately resulting in the selective exclusion of the cytotoxic subset. Using functional assays, we observed intratumoral NK cell death and a reduction in cytotoxic capacities depending on the tumor stage. Finally, our analyses of human public dataset on lung cancer corroborate these findings, revealing a parallel dysfunctional maturation process of NK cells during tumor progression. These results highlight additional mechanisms by which tumor cells escape from NK cell cytotoxicity, therefore paving the way for tailored therapeutic strategies. Ā© 2024 The Author(s).

    • Mus musculus (House mouse)
    • ,
    • Immunology and Microbiology
    Dichotomous outcomes of TNFR1 and TNFR2 signaling in NK cell-mediated immune responses during inflammation.

    In Nature Communications on 14 November 2024 by McCulloch, T., Rossi, G. R., et al.

    Natural killer (NK) cell function is regulated by a balance of activating and inhibitory signals. Tumor necrosis factor (TNF) is an inflammatory cytokine ubiquitous across homeostasis and disease, yet its role in regulation of NK cells remains unclear. Here, we find upregulation of the immune checkpoint protein, T cell immunoglobulin and mucin domain 3 (Tim3), is a biomarker of TNF signaling in NK cells during Salmonella Typhimurium infection. In mice with conditional deficiency of either TNF receptor 1 (TNFR1) or TNF receptor 2 (TNFR2) in NK cells, we find TNFR1 limits bacterial clearance whereas TNFR2 promotes it. Mechanistically, via single cell RNA sequencing we find that both TNFR1 and TNFR2 induce the upregulation of Tim3, while TNFR1 accelerates NK cell death but TNFR2 promotes NK cell accumulation and effector function. Our study thus highlights the complex interplay of TNF-based regulation of NK cells by the two TNF receptors during inflammation. Ā© 2024. The Author(s).

    • Cancer Research
    • ,
    • Cell Biology
    Targeting Catechol-O-Methyltransferase Induces Mitochondrial Dysfunction and Enhances the Efficacy of Radiotherapy in Glioma.

    In Cancer Research on 4 November 2024 by Jiao, M., Pirozzi, C. J., et al.

    Radiotherapy (RT) is commonly used to try to eliminate any remaining tumor cells following surgical resection of glioma. However, tumor recurrence is prevalent, highlighting the unmet medical need to develop therapeutic strategies to enhance the efficacy of RT in glioma. Focusing on the radiosensitizing potential of the currently approved drugs known to cross the blood-brain barrier can facilitate rapid clinical translation. Here, we assessed the role of catechol-O-methyltransferase (COMT), a key enzyme to degrade catecholamines and a drug target for Parkinson's disease, in glioma treatment. Analysis of The Cancer Genome Atlas data showed significantly higher COMT expression levels in both low-grade glioma and glioblastoma compared to normal brain tissues. Inhibition of COMT by genetic knockout or FDA-approved COMT inhibitors significantly sensitized glioma cells to RT in vitro and in vivo. Mechanistically, COMT inhibition in glioma cells led to mitochondria dysfunction and increased mitochondrial RNA release into the cytoplasm, activating the cellular antiviral double-stranded RNA sensing pathway and type I interferon (IFN) response. Elevated type I IFNs stimulated the phagocytic capacity of microglial cells, enhancing RT efficacy. Given the long-established safety record of the COMT inhibitors, these findings provide a solid rationale to evaluate them in combination with RT in patients with glioma. Significance: Inhibition of catechol-O-methyltransferase, a well-established drug target in Parkinson's disease, interferes with mitochondrial electron transport and induces mitochondrial double-stranded RNA leakage, activating type I interferon signaling and sensitizing glioma to radiotherapy. ©2024 The Authors; Published by the American Association for Cancer Research.

    • Cancer Research
    • ,
    • Immunology and Microbiology
    A PD-1-targeted, receptor-masked IL-2 immunocytokine that engages IL-2Rα strengthens T cell-mediated anti-tumor therapies.

    In Cell Reports Medicine on 15 October 2024 by Wu, J., Bloch, N., et al.

    The clinical use of interleukin-2 (IL-2) for cancer immunotherapy is limited by severe toxicity. Emerging IL-2 therapies with reduced IL-2 receptor alpha (IL-2Rα) binding aim to mitigate toxicity and regulatory T cell (Treg) expansion but have had limited clinical success. Here, we show that IL-2Rα engagement is critical for the anti-tumor activity of systemic IL-2 therapy. A "non-α" IL-2 mutein induces systemic expansion of CD8+ T cells and natural killer (NK) cells over Tregs but exhibits limited anti-tumor efficacy. We develop a programmed cell death protein 1 (PD-1)-targeted, receptor-masked IL-2 immunocytokine, PD1-IL2Ra-IL2, which attenuates systemic IL-2 activity while maintaining the capacity to engage IL-2Rα on PD-1+ T cells. Mice treated with PD1-IL2Ra-IL2 show no systemic toxicities observed with unmasked IL-2 treatment yet achieve robust tumor growth control. Furthermore, PD1-IL2Ra-IL2 can be effectively combined with other T cell-mediated immunotherapies to enhance anti-tumor responses. These findings highlight the therapeutic potential of PD1-IL2Ra-IL2 as a targeted, receptor-masked, and "α-maintained" IL-2 therapy for cancer. Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.

    • Mus musculus (House mouse)
    • ,
    • Cancer Research
    • ,
    • Immunology and Microbiology
    TGF-β induces an atypical EMT to evade immune mechanosurveillance in lung adenocarcinoma dormant metastasis

    Preprint on BioRxiv : the Preprint Server for Biology on 15 October 2024 by Wang, Z., Elbanna, Y., et al.

    The heterogeneity of epithelial-to-mesenchymal transition (EMT) programs is manifest in the diverse EMT-like phenotypes occurring during tumor progression. However, little is known about the mechanistic basis and functional role of specific forms of EMT in cancer. Here we address this question in lung adenocarcinoma (LUAD) cells that enter a dormancy period in response to TGF-β upon disseminating to distant sites. LUAD cells with the capacity to enter dormancy are characterized by expression of SOX2 and NKX2-1 primitive progenitor markers. In these cells, TGF-β induces growth inhibition accompanied by a full EMT response that subsequently transitions into an atypical mesenchymal state of round morphology and lacking actin stress fibers. TGF-β induces this transition by driving the expression of the actin-depolymerizing factor gelsolin, which changes a migratory, stress fiber-rich mesenchymal phenotype into a cortical actin-rich, spheroidal state. This transition lowers the biomechanical stiffness of metastatic progenitors, protecting them from killing by mechanosensitive cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells. Inhibiting this actin depolymerization process clears tissues of dormant metastatic cells. Thus, LUAD primitive progenitors undergo an atypical EMT as part of a strategy to evade immune-mediated elimination during dormancy. Our results provide a mechanistic basis and functional role of this atypical EMT response of LUAD metastatic progenitors and further illuminate the role of TGF-β as a crucial driver of immune evasive metastatic dormancy.

1 2 3 4 5 6 7 8 9 10 11 12 13