InVivoMAb mouse IgG2b isotype control, unknown specificity
Product Details
The MPC-11 monoclonal antibody is ideal for use as a non-reactive isotype-matched control for mouse IgG2b antibodies in most in vivo and in vitro applications.Specifications
| Isotype | Mouse IgG2b,Ā Īŗ |
|---|---|
| Recommended Dilution Buffer | InVivoPure pH 7.0 Dilution Buffer |
| Conjugation | This product is unconjugated. Conjugation is available via our Antibody Conjugation Services. |
| 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 G |
| RRID | AB_1107791 |
| 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 Dilution Buffer
InVivoPure pH 7.0 Dilution Buffer
Turnis, M. E., et al. (2016). "Interleukin-35 Limits Anti-Tumor Immunity" Immunity 44(2): 316-329. PubMed
Regulatory T (Treg) cells pose a major barrier to effective anti-tumor immunity. Although Treg cell depletion enhances tumor rejection, the ensuing autoimmune sequelae limits its utility in the clinic and highlights the need for limiting Treg cell activity within the tumor microenvironment. Interleukin-35 (IL-35) is a Treg cell-secreted cytokine that inhibits T cell proliferation and function. Using an IL-35 reporter mouse, we observed substantial enrichment of IL-35(+) Treg cells in tumors. Neutralization with an IL-35-specific antibody or Treg cell-restricted deletion of IL-35 production limited tumor growth in multiple murine models of human cancer. Limiting intratumoral IL-35 enhanced T cell proliferation, effector function, antigen-specific responses, and long-term T cell memory. Treg cell-derived IL-35 promoted the expression of multiple inhibitory receptors (PD1, TIM3, LAG3), thereby facilitating intratumoral T cell exhaustion. These findings reveal previously unappreciated roles for IL-35 in limiting anti-tumor immunity and contributing to T cell dysfunction in the tumor microenvironment.
Barreira da Silva, R., et al. (2015). "Dipeptidylpeptidase 4 inhibition enhances lymphocyte trafficking, improving both naturally occurring tumor immunity and immunotherapy" Nat Immunol 16(8): 850-858. PubMed
The success of antitumor immune responses depends on the infiltration of solid tumors by effector T cells, a process guided by chemokines. Here we show that in vivo post-translational processing of chemokines by dipeptidylpeptidase 4 (DPP4, also known as CD26) limits lymphocyte migration to sites of inflammation and tumors. Inhibition of DPP4 enzymatic activity enhanced tumor rejection by preserving biologically active CXCL10 and increasing trafficking into the tumor by lymphocytes expressing the counter-receptor CXCR3. Furthermore, DPP4 inhibition improved adjuvant-based immunotherapy, adoptive T cell transfer and checkpoint blockade. These findings provide direct in vivo evidence for control of lymphocyte trafficking via CXCL10 cleavage and support the use of DPP4 inhibitors for stabilizing biologically active forms of chemokines as a strategy to enhance tumor immunotherapy.
Le Saout, C., et al. (2014). "Chronic exposure to type-I IFN under lymphopenic conditions alters CD4 T cell homeostasis" PLoS Pathog 10(3): e1003976. PubMed
HIV infection and the associated chronic immune activation alter T cell homeostasis leading to CD4 T cell depletion and CD8 T cell expansion. The mechanisms behind these outcomes are not totally defined and only partially explained by the direct cytopathic effect of the virus. In this manuscript, we addressed the impact of lymphopenia and chronic exposure to IFN-alpha on T cell homeostasis. In a lymphopenic murine model, this interaction led to decreased CD4 counts and CD8 T cell expansion in association with an increase in the Signal Transducer and Activator of Transcription 1 (STAT1) levels resulting in enhanced CD4 T cell responsiveness to IFN-alpha. Thus, in the setting of HIV infection, chronic stimulation of this pathway could be detrimental for CD4 T cell homeostasis.
Larena, M., et al. (2011). "Pivotal role of antibody and subsidiary contribution of CD8+ T cells to recovery from infection in a murine model of Japanese encephalitis" J Virol 85(11): 5446-5455. PubMed
The immunological correlates for recovery from primary Japanese encephalitis virus (JEV) infection in humans and experimental animals remain poorly defined. To investigate the relative importance of the adaptive immune responses, we have established a mouse model for Japanese encephalitis in which a low-dose virus inoculum was administered into the footpads of adult C57BL/6 mice. In this model, ~60% of the mice developed a fatal encephalitis and a virus burden in the central nervous system (CNS). Using mice lacking B cells (muMT(-/-) mice) and immune B cell transfer to wild-type mice, we show a critically important role for humoral immunity in preventing virus spread to the CNS. T cell help played an essential part in the maintenance of an effective antibody response necessary to combat the infection, since mice lacking major histocompatibility complex class II showed truncated IgM and blunted IgG responses and uniformly high lethality. JEV infection resulted in extensive CD8(+) T cell activation, judged by upregulation of surface markers CD69 and CD25 and cytokine production after stimulation with a JEV NS4B protein-derived H-2D(b)-binding peptide and trafficking of virus-immune CD8(+) T cells into the CNS. However, no significant effect of CD8(+) T cells on the survival phenotype was found, which was corroborated in knockout mice lacking key effector molecules (Fas receptor, perforin, or granzymes) of cytolytic pathways triggered by T lymphocytes. Accordingly, CD8(+) T cells are mostly dispensable for recovery from infection with JEV. This finding highlights the conflicting role that CD8(+) T cells play in the pathogenesis of JEV and closely related encephalitic flaviviruses such as West Nile virus.
Lamere, M. W., et al. (2011). "Regulation of antinucleoprotein IgG by systemic vaccination and its effect on influenza virus clearance" J Virol 85(10): 5027-5035. PubMed
Seasonal influenza epidemics recur due to antigenic drift of envelope glycoprotein antigens and immune evasion of circulating viruses. Additionally, antigenic shift can lead to influenza pandemics. Thus, a universal vaccine that protects against multiple influenza virus strains could alleviate the continuing impact of this virus on human health. In mice, accelerated clearance of a new viral strain (cross-protection) can be elicited by prior infection (heterosubtypic immunity) or by immunization with the highly conserved internal nucleoprotein (NP). Both heterosubtypic immunity and NP-immune protection require antibody production. Here, we show that systemic immunization with NP readily accelerated clearance of a 2009 pandemic H1N1 influenza virus isolate in an antibody-dependent manner. However, human immunization with trivalent inactivated influenza virus vaccine (TIV) only rarely and modestly boosted existing levels of anti-NP IgG. Similar results were observed in mice, although the reaction could be enhanced with adjuvants, by adjusting the stoichiometry among NP and other vaccine components, and by increasing the interval between TIV prime and boost. Importantly, mouse heterosubtypic immunity that had waned over several months could be enhanced by injecting purified anti-NP IgG or by boosting with NP protein, correlating with a long-lived increase in anti-NP antibody titers. Thus, current immunization strategies poorly induce NP-immune antibody that is nonetheless capable of contributing to long-lived cross-protection. The high conservation of NP antigen and the known longevity of antibody responses suggest that the antiviral activity of anti-NP IgG may provide a critically needed component of a universal influenza vaccine.
IL-6 underlies microenvironment immunosuppression and resistance to therapy in glioblastoma
Preprint on BioRxiv : the Preprint Server for Biology on 14 March 2025 by Young, J. S., Cho, N. W., et al.
The glioblastoma tumor immune microenvironment (TIME) is an immunosuppressive barrier to therapy that encumbers glioblastoma responses to immune checkpoint inhibition (ICI). Immunosuppressive cytokines, pro-tumor myeloid cells, and exhausted T-cells are hallmarks of the glioblastoma TIME. Here we integrate spatial and single-cell analyses of patient-matched human glioblastoma samples before and after ICI with genetic, immunologic, single-cell, and pharmacologic studies in preclinical models to reveal that interleukin-6 (IL-6) inhibition reprograms the glioblastoma TIME to sensitize mouse glioblastoma to ICI and radiotherapy. Rare human glioblastoma patients who achieve clinical responses to ICI have lower pre-treatment IL-6 levels compared to glioblastomas who do not respond to ICI. Immune stimulatory gene therapy suppresses IL-6 tumor levels in preclinical murine models of glioblastoma. Furthermore, survival was longer in Il-6 knockout mice with orthotopic SB28 glioblastoma relative to wild-type mice. IL-6 blockade with a neutralizing antibody transiently sensitizes mouse glioblastoma to anti-PD-1 by increasing MHCII+ monocytes, CD103+ migratory dendritic cells (DCs), CD11b+ conventional DCs, and effector CD8+ T cells, and decreasing immunosuppressive Tregs. To translate these findings to a combination treatment strategy for recurrent glioblastoma patients, we show that IL-6 blockade plus ICI durably sensitizes mouse glioblastoma to high-dose radiotherapy.
- WB,
- Mus musculus (House mouse),
- Cancer Research
Toll-Like receptor 3-mediated interferon-Ī² production is suppressed by oncostatin m and a broader epithelial-mesenchymal transition program.
In Breast Cancer Research : BCR on 26 November 2024 by Chernosky, N. M., Tamagno, I., et al.
Patients with Triple Negative Breast Cancer (TNBC) currently lack targeted therapies, and consequently face higher mortality rates when compared to patients with other breast cancer subtypes. The tumor microenvironment (TME) cytokine Oncostatin M (OSM) reprograms TNBC cells to a more stem-like/mesenchymal state, conferring aggressive cancer cell properties such as enhanced migration and invasion, increased tumor-initiating capacity, and intrinsic resistance to the current standards of care. In contrast to OSM, Interferon-Ī² (IFN-Ī²) promotes a more differentiated, epithelial cell phenotype in addition to its role as an activator of anti-tumor immunity. Importantly, OSM suppresses the production of IFN-Ī², although the mechanism of IFN-Ī² suppression has not yet been elucidated. IFN-Ī² production and downstream autocrine signaling were assessed via quantitative real-time PCR (qRT-PCR) and Western blotting in TNBC cells following exposure to OSM. RNA-sequencing (RNA-seq) was used to assess an IFN-Ī² metagene signature, and to assess the expression of innate immune sensors, which are upstream activators of IFN-Ī². Cell migration was assessed using an in vitro chemotaxis assay. Additionally, TNBC cells were exposed to TGF-Ī²1, Snail, and Zeb1, and IFN-Ī² production and downstream autocrine signaling were assessed via RNA-seq, qRT-PCR, and Western blotting. Here, we identify the repression of Toll-like Receptor 3 (TLR3), an innate immune sensor, as the key molecular event linking OSM signaling and the repression of IFN-Ī² transcription, production, and autocrine IFN signaling. Moreover, we demonstrate that additional epithelial-mesenchymal transition-inducing factors, such as TGF-Ī²1, Snail, and Zeb1, similarly suppress TLR3-mediated IFN-Ī² production and signaling. Our findings provide a novel insight into the regulation of TLR3 and IFN-Ī² production in TNBC cells, which are known indicators of treatment responses to DNA-damaging therapies. Furthermore, strategies to stimulate TLR3 in order to increase IFN-Ī² within the TME may be ineffective in stem-like/mesenchymal cells, as TLR3 is strongly repressed. Rather, we propose that therapies targeting OSM or OSM receptor would reverse the stem-like/mesenchymal program and restore TLR3-mediated IFN-Ī² production within the TME, facilitating improved responses to current therapies. Ā© 2024. The Author(s).
- Cancer Research,
- Immunology and Microbiology
CDK4/6 Inhibition Induces CD8+ T Cell Antitumor Immunity via MIF-Induced Functional Orchestration of Tumor-Associated Macrophages
Preprint on Research Square on 7 November 2024 by Deng, C., He, L., et al.
Abstract Cyclin-dependent kinases 4 and 6 (CDK4/6) regulate cell cycle progression from the G1 to S phase. Recent findings have demonstrated that CDK4/6 inhibition (CDK4/6i) enhances antitumor immunity, as evidenced by increased tumor infiltration of CD8+ T cells, though the underlying mechanism remains unclear. Our current study reveals that CDK4/6i enhances intratumoral CD8+ T cell infiltration in breast tumors through the functional reprogramming of tumor-associated macrophages (TAMs), facilitating indirect interactions between tumor cells and CD8+ T cells. Mechanistically, CDK4/6i enhances the proliferation and activation of M1 macrophages and promote the polarization of M2 to M1 macrophages via the macrophage migration inhibitory factor (MIF)-CD44/CD74 axis between tumor cells and macrophages. CDK4/6i-trained M1 TAMs increase and activate CD8+ T cells through MHC-I antigen presentation machinery. Inhibition of MIF in tumor cells or loss of MIF reverses the immunostimulatory effects of CDK4/6i on macrophages and subsequent CD8+ T cell antitumor immunity. Therefore, CDK4/6i-trained M1 TAM supernatant therapy surmounts the immunosuppressive tumor microenvironment and invokes a tumor response to low-dose PD-1 immune checkpoint blockade therapy in breast cancers.
- 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.
- 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.
- Cancer Research,
- Immunology and Microbiology
Cancer cell plasticity defines response to immunotherapy in cutaneous squamous cell carcinoma.
In Nature Communications on 24 June 2024 by Lorenzo-Sanz, L., Lopez-Cerda, M., et al.
Immune checkpoint blockade (ICB) approaches have changed the therapeutic landscape for many tumor types. However, half of cutaneous squamous cell carcinoma (cSCC) patients remain unresponsive or develop resistance. Here, we show that, during cSCC progression in male mice, cancer cells acquire epithelial/mesenchymal plasticity and change their immune checkpoint (IC) ligand profile according to their features, dictating the IC pathways involved in immune evasion. Epithelial cancer cells, through the PD-1/PD-L1 pathway, and mesenchymal cancer cells, through the CTLA-4/CD80 and TIGIT/CD155 pathways, differentially block antitumor immune responses and determine the response to ICB therapies. Accordingly, the anti-PD-L1/TIGIT combination is the most effective strategy for blocking the growth of cSCCs that contain both epithelial and mesenchymal cancer cells. The expression of E-cadherin/Vimentin/CD80/CD155 proteins in cSCC, HNSCC and melanoma patient samples predicts response to anti-PD-1/PD-L1 therapy. Collectively, our findings indicate that the selection of ICB therapies should take into account the epithelial/mesenchymal features of cancer cells. Ā© 2024. The Author(s).
- Immunology and Microbiology,
- Cancer Research
Spon1+ inflammatory monocytes promote collagen remodeling and lung cancer metastasis through lipoprotein receptor 8 signaling.
In JCI Insight on 8 May 2024 by Whately, K. M., Sengottuvel, N., et al.
PubMed
Lung cancer is the leading cause of cancer-related deaths in the world, and non-small cell lung cancer (NSCLC) is the most common subset. We previously found that infiltration of tumor inflammatory monocytes (TIMs) into lung squamous carcinoma (LUSC) tumors is associated with increased metastases and poor survival. To further understand how TIMs promote metastases, we compared RNA-Seq profiles of TIMs from several LUSC metastatic models with inflammatory monocytes (IMs) of non-tumor-bearing controls. We identified Spon1 as upregulated in TIMs and found that Spon1 expression in LUSC tumors corresponded with poor survival and enrichment of collagen extracellular matrix signatures. We observed SPON1+ TIMs mediate their effects directly through LRP8 on NSCLC cells, which resulted in TGF-Ī²1 activation and robust production of fibrillar collagens. Using several orthogonal approaches, we demonstrated that SPON1+ TIMs were sufficient to promote NSCLC metastases. Additionally, we found that Spon1 loss in the host, or Lrp8 loss in cancer cells, resulted in a significant decrease of both high-density collagen matrices and metastases. Finally, we confirmed the relevance of the SPON1/LRP8/TGF-Ī²1 axis with collagen production and survival in patients with NSCLC. Taken together, our study describes how SPON1+ TIMs promote collagen remodeling and NSCLC metastases through an LRP8/TGF-Ī²1 signaling axis.
- Cancer Research,
- Immunology and Microbiology
NFKB2 mediates colorectal cancer cell immune escape and metastasis in a STAT2/PDāL1ādependent manner.
In MedComm (2020) on 1 May 2024 by Zhang, J., Ma, F., et al.
This study systematically analyzed the molecular mechanism and function of nuclear factor kappa B subunit 2 (NFKB2) in colorectal cancer (CRC) to investigate the potential of NFKB2 as a therapeutic target for CRC. Various experimental techniques, including RNA sequencing, proteome chip assays, and small molecule analysis, were used to obtain a deeper understanding of the regulation of NFKB2 in CRC. The results revealed that NFKB2 was upregulated in a significant proportion of patients with advanced hepatic metastasis of CRC. NFKB2 played an important role in promoting tumor growth through CD8+ T-cell exhaustion. Moreover, NFKB2 directly interacted with signal transducer and activator of transcription 2 (STAT2), leading to increased phosphorylation of STAT2 and the upregulation of programmed death ligand 1 (PD-L1). Applying a small molecule inhibitor of NFKB2 (Rg5) led to a reduction in PD-L1 expression and improved response to programmed death-1 blockade-based immunotherapy. In conclusion, the facilitated NFKB2-STAT2/PD-L1 axis may suppress immune surveillance in CRC and targeting NFKB2 may enhance the efficacy of immunotherapeutic strategies. Our results provide novel insights into the molecular mechanisms underlying the contribution of NFKB2 in CRC immune escape. Ā© 2024 The Authors. MedComm published by Sichuan International Medical Exchange & Promotion Association (SCIMEA) and John Wiley & Sons Australia, Ltd.
- Cancer Research,
- Immunology and Microbiology
Systematic investigation of chemo-immunotherapy synergism to shift anti-PD-1 resistance in cancer.
In Nature Communications on 12 April 2024 by Wang, Y., Pattarayan, D., et al.
Chemo-immunotherapy combinations have been regarded as one of the most practical ways to improve immunotherapy response in cancer patients. In this study, we integrate the transcriptomics data from anti-PD-1-treated tumors and compound-treated cancer cell lines to systematically screen for chemo-immunotherapy synergisms in silico. Through analyzing anti-PD-1 induced expression changes in patient tumors, we develop a shift ability score to measure if a chemotherapy or a small molecule inhibitor treatment can shift anti-PD-1 resistance in tumor cells. By applying shift ability analysis to 41,321 compounds and 16,853 shRNA treated cancer cell lines transcriptomic data, we characterize the landscape of chemo-immunotherapy synergism and experimentally validated a mitochondrial RNA-dependent mechanism for drug-induced immune activation in tumor. Our study represents an effort to mechanistically characterize chemo-immunotherapy synergism and will facilitate future pre-clinical and clinical studies. Ā© 2024. The Author(s).
- Cancer Research,
- Plant Science
Anti-cancer effects of Coix seed extract through KCTD9-mediated ubiquitination of TOP2A in lung adenocarcinoma.
In Cell Division on 20 February 2024 by Jiang, J., Li, X., et al.
Coix seed extract (CSE), a traditional Chinese medicine, has been reported as an adjunctive therapy in cancers. However, the molecular targets are largely unclear. The study is designed to unveil its function in lung adenocarcinoma (LUAD) and the possible molecular mechanism. The HERB database was utilized to predict the molecular targets of the Coix seed, followed by prognostic value prediction in the Kaplan-Meier Plotter database. LUAD cells were infected with sh-KCTD9 after co-culture with CSE, and cell viability, growth, proliferation, and apoptosis were determined. The substrates of KCTD9 were predicted using a protein-protein interaction network and verified. The expression of PD-L1, the contents of TNF-Ī±, IFN-Ī³, CXCL10, and CXCL9 in the co-culture system of LUAD cells and T cells and the proliferation of T cells were evaluated to study the immune escape of LUAD cells in response to CSE and sh-KCTD9. Lastly, tumor growth and immune escape were observed in tumor-bearing mice. CSE inhibited malignant behavior and immune escape of LUAD cells, and the reduction of KCTD9 reversed the inhibitory effect of CSE on malignant behavior and immune escape of LUAD cells. Knockdown of KCTD9 expression inhibited ubiquitination modification of TOP2A, and knockdown of TOP2A suppressed immune escape of LUAD cells in the presence of knockdown of KCTD9. CSE exerted anticancer effects in mice, but the reduction of KCTD9 partially compromised the anticancer effect of CSE. CSE inhibits immune escape and malignant progression of LUAD through KCTD9-mediated ubiquitination modification of TOP2A. Ā© 2024. The Author(s).
- Cancer Research
Targeting eIF4A triggers an interferon response to synergize with chemotherapy and suppress triple-negative breast cancer.
In The Journal of Clinical Investigation on 15 December 2023 by Zhao, N., Kabotyanski, E. B., et al.
PubMed
Protein synthesis is frequently dysregulated in cancer and selective inhibition of mRNA translation represents an attractive cancer therapy. Here, we show that therapeutically targeting the RNA helicase eIF4A with zotatifin, the first-in-class eIF4A inhibitor, exerts pleiotropic effects on both tumor cells and the tumor immune microenvironment in a diverse cohort of syngeneic triple-negative breast cancer (TNBC) mouse models. Zotatifin not only suppresses tumor cell proliferation but also directly repolarizes macrophages toward an M1-like phenotype and inhibits neutrophil infiltration, which sensitizes tumors to immune checkpoint blockade. Mechanistic studies revealed that zotatifin reprograms the tumor translational landscape, inhibits the translation of Sox4 and Fgfr1, and induces an interferon (IFN) response uniformly across models. The induction of an IFN response is partially due to the inhibition of Sox4 translation by zotatifin. A similar induction of IFN-stimulated genes was observed in breast cancer patient biopsies following zotatifin treatment. Surprisingly, zotatifin significantly synergizes with carboplatin to trigger DNA damage and an even heightened IFN response, resulting in T cell-dependent tumor suppression. These studies identified a vulnerability of eIF4A in TNBC, potential pharmacodynamic biomarkers for zotatifin, and provide a rationale for new combination regimens consisting of zotatifin and chemotherapy or immunotherapy as treatments for TNBC.
- Cancer Research,
- Immunology and Microbiology
Helicobacter pylori CagA promotes immune evasion of gastric cancer by upregulating PD-L1 level in exosomes.
In IScience on 15 December 2023 by Wang, J., Deng, R., et al.
PubMed
Cytotoxin-associated gene A (CagA) of Helicobacter pylori (Hp) may promote immune evasion of Hp-infected gastric cancer (GC), but potential mechanisms are still under explored. In this study, the positive rates of CagA and PD-L1 protein in tumor tissues and the high level of exosomal PD-L1 protein in plasma exosomes were significantly associated with the elevated stages of tumor node metastasis (TNM) in Hp-infected GC. Moreover, the positive rate of CagA was positively correlated with the positive rate of PD-L1 in tumor tissues and the level of PD-L1 protein in plasma exosomes, and high level of exosomal PD-L1 might indicate poor prognosis of Hp-infected GC. Mechanically, CagA increased PD-L1 level in exosomes derived from GC cells by inhibiting p53 and miRNA-34a, suppressing proliferation and anticancer effect of CD8+ TĀ cells. This study provides sights for understanding immune evasion mediated by PD-L1. Targeting CagA and exosomal PD-L1 may improve immunotherapy efficacy of Hp-infected GC. Ā© 2023 The Authors.
- Genetics,
- Immunology and Microbiology
Mice with FVB-derived sequence on chromosome 17 succumb to disseminated virus infection due to aberrant NK cell and TĀ cell responses.
In IScience on 17 November 2023 by Tibbs, T. N., Donoghue, L. J., et al.
PubMed
Zoonotic arenavirus infections can result in viral hemorrhagic disease, characterized by platelet loss, petechia, and multi-organ injury. The mechanisms governing these outcomes are likely impacted by virus strain and infection dose, as well as an individual's genetic background and immune constitution. To better understand the processes leading to severe pathogenesis, we compared two strains of inbred mice, C57BL/6J (B6) and FVB/NJ (FVB), that have diametrically opposed outcomes during disseminated lymphocytic choriomeningitis virus (LCMV) infection. Infection caused minimal pathogenesis in B6 mice, whereas FVB mice developed acute hepatitis and perished due, in part, to aberrant NK cell and TĀ cell responses. Susceptible mice showed an outgrowth of cytolytic CD4+ TĀ cells and loss of Treg cells. B6 congenic mice with the FVB allele at a 25Mb locus on chromosome 17 recapitulated FVB pathogenesis upon infection. A locus containing a limited number of variants in immune-related genes greatly impacts survival during infection. Ā© 2023 The Author(s).
- Immunology and Microbiology,
- Neuroscience,
- Cancer Research
TIM-3 blockade in diffuse intrinsic pontine glioma models promotes tumor regression and antitumor immune memory.
In Cancer Cell on 13 November 2023 by Ausejo-Mauleon, I., Labiano, S., et al.
PubMed
Diffuse intrinsic pontine glioma (DIPG) is an aggressive brain stem tumor and the leading cause of pediatric cancer-related death. To date, these tumors remain incurable, underscoring the need for efficacious therapies. In this study, we demonstrate that the immune checkpoint TIM-3 (HAVCR2) is highly expressed in both tumor cells and microenvironmental cells, mainly microglia and macrophages, in DIPG. We show that inhibition of TIM-3 in syngeneic models of DIPG prolongs survival and produces long-term survivors free of disease that harbor immune memory. This antitumor effect is driven by the direct effect of TIM-3 inhibition in tumor cells, the coordinated action of several immune cell populations, and the secretion of chemokines/cytokines that create a proinflammatory tumor microenvironment favoring a potent antitumor immune response. This work uncovers TIM-3 as a bona fide target in DIPG and supports its clinical translation. Copyright Ā© 2023 The Author(s). Published by Elsevier Inc. All rights reserved.
- Cancer Research,
- Immunology and Microbiology
Targeted Inhibition of lncRNA Malat1 Alters the Tumor Immune Microenvironment in Preclinical Syngeneic Mouse Models of Triple-Negative Breast Cancer.
In Cancer Immunology Research on 1 November 2023 by Oluwatoyosi, A., Shen, Y., et al.
PubMed
Long noncoding RNAs (lncRNA) play an important role in gene regulation in both normal tissues and cancer. Targeting lncRNAs is a promising therapeutic approach that has become feasible through the development of gapmer antisense oligonucleotides (ASO). Metastasis-associated lung adenocarcinoma transcript (Malat1) is an abundant lncRNA whose expression is upregulated in several cancers. Although Malat1 increases the migratory and invasive properties of tumor cells, its role in the tumor microenvironment (TME) is still not well defined. We explored the connection between Malat1 and the tumor immune microenvironment (TIME) using several immune-competent preclinical syngeneic Tp53-null triple-negative breast cancer (TNBC) mouse models that mimic the heterogeneity and immunosuppressive TME found in human breast cancer. Using a Malat1 ASO, we were able to knockdown Malat1 RNA expression resulting in a delay in primary tumor growth, decreased proliferation, and increased apoptosis. In addition, immunophenotyping of tumor-infiltrating lymphocytes revealed that Malat1 inhibition altered the TIME, with a decrease in immunosuppressive tumor-associated macrophages (TAM) and myeloid-derived suppressor cells (MDSC) as well as an increase in cytotoxic CD8+ T cells. Malat1 depletion in tumor cells, TAMs, and MDSCs decreased immunosuppressive cytokine/chemokine secretion whereas Malat1 inhibition in T cells increased inflammatory secretions and T-cell proliferation. Combination of a Malat1 ASO with chemotherapy or immune checkpoint blockade (ICB) improved the treatment responses in a preclinical model. These studies highlight the immunostimulatory effects of Malat1 inhibition in TNBC, the benefit of a Malat1 ASO therapeutic, and its potential use in combination with chemotherapies and immunotherapies. Ā©2023 The Authors; Published by the American Association for Cancer Research.
- Cancer Research
Endothelial cells are a key target of IFN-g during response to combined PD-1/CTLA-4 ICB treatment in a mouse model of bladder cancer.
In IScience on 20 October 2023 by Freshour, S. L., Chen, T. H., et al.
PubMed
To explore mechanisms of response to combined PD-1/CTLA-4 immune checkpoint blockade (ICB) treatment in individual cell types, we generated scRNA-seq using a mouse model of invasive urothelial carcinoma with three conditions: untreated tumor, treated tumor, and tumor treated after CD4+ TĀ cell depletion. After classifying tumor cells based on detection of somatic variants and assigning non-tumor cell types using SingleR, we performed differential expression analysis, overrepresentation analysis, and gene set enrichment analysis (GSEA) within each cell type. GSEA revealed that endothelial cells were enriched for upregulated IFN-g response genes when comparing treated cells to both untreated cells and cells treated after CD4+ TĀ cell depletion. Functional analysis showed that knocking out IFNgR1 in endothelial cells inhibited treatment response. Together, these results indicated that IFN-g signaling in endothelial cells is a key mediator of ICB induced anti-tumor activity. Ā© 2023 The Authors.
- Mus musculus (House mouse),
- Cancer Research
Neutrophil-Mediated Tumor-Targeting Delivery System of Oncolytic Bacteria Combined with ICB for Melanoma Lung Metastasis Therapy.
In Advanced Science (Weinheim, Baden-Wurttemberg, Germany) on 1 October 2023 by Liu, L., Xin, W., et al.
PubMed
Oncolytic bacteria are the most promising tumor target vector. Questions also remain regarding finding a balance between the therapeutic efficacy and safety of oncolytic bacteria. The critical measure of how this balance is maintained is the improvement in tumor colonization. Attenuated Salmonella typhimurium (VNP20009) as the only Salmonella strain to be evaluated in a clinical trial is a potential tumor therapeutic bacterium. A delivery system with controlled release of VNP after being loaded into neutrophils, which significantly increases the tumor-targeting of VNP and enhances its therapeutic efficacy in a melanoma lung metastasis model is constructed. To improve the synergistic therapeutic effect, a PD1 nanobody is applied to this system (NE(PD1nb)). NE(PD1nb) activate dendritic cells (DCs) differentiation and stimulate the M1-like differentiation of macrophages, and induce CD4+ T-cells maturity and cytotoxic CD8+ T-cells activation through DCs tumor antigen presentation. Ā© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.
- Immunology and Microbiology
Monoclonal antibodies against lipopolysaccharide protect against Pseudomonas aeruginosa challenge in mice.
In Frontiers in Cellular and Infection Microbiology on 10 July 2023 by Kang, J., Mateu-BorrƔs, M., et al.
PubMed
Pseudomonas aeruginosa is a common cause of hospital-acquired infections, including central line-associated bloodstream infections and ventilator-associated pneumonia. Unfortunately, effective control of these infections can be difficult, in part due to the prevalence of multi-drug resistant strains of P. aeruginosa. There remains a need for novel therapeutic interventions against P. aeruginosa, and the use of monoclonal antibodies (mAb) is a promising alternative strategy to current standard of care treatments such as antibiotics. To develop mAbs against P. aeruginosa, we utilized ammonium metavanadate, which induces cell envelope stress responses and upregulates polysaccharide expression. Mice were immunized with P. aeruginosa grown with ammonium metavanadate and we developed two IgG2b mAbs, WVDC-0357 and WVDC-0496, directed against the O-antigen lipopolysaccharide of P. aeruginosa. Functional assays revealed that WVDC-0357 and WVDC-0496 directly reduced the viability of P. aeruginosa and mediated bacterial agglutination. In a lethal sepsis model of infection, prophylactic treatment of mice with WVDC-0357 and WVDC-0496 at doses as low as 15 mg/kg conferred 100% survival against challenge. In both sepsis and acute pneumonia models of infection, treatment with WVDC-0357 and WVDC-0496 significantly reduced bacterial burden and inflammatory cytokine production post-challenge. Furthermore, histopathological examination of the lungs revealed that WVDC-0357 and WVDC-0496 reduced inflammatory cell infiltration. Overall, our results indicate that mAbs directed against lipopolysaccharide are a promising therapy for the treatment and prevention of P. aeruginosa infections. Copyright Ā© 2023 Kang, Mateu-BorrĆ”s, Monroe, Sen-Kilic, Miller, Dublin, Huckaby, Yang, Pyles, Nunley, Chapman, Amin, Damron and Barbier.
- Cancer Research,
- Immunology and Microbiology
CTLA-4 blockade induces tumor pyroptosis via CD8+ TĀ cells in head and neck squamous cell carcinoma.
In Molecular Therapy on 5 July 2023 by Wang, S., Wu, Z. Z., et al.
Immune checkpoint blockade (ICB) treatment has demonstrated excellent medical effects in oncology, and it is one of the most sought after immunotherapies for tumors. However, there are several issues with ICB therapy, including low response rates and a lack of effective efficacy predictors. Gasdermin-mediated pyroptosis is a typical inflammatory death mode. We discovered that increased expression of gasdermin protein was linked to a favorable tumor immune microenvironment and prognosis in head and neck squamous cell carcinoma (HNSCC). We used the mouse HNSCC cell lines 4MOSC1 (responsive to CTLA-4 blockade) and 4MOSC2 (resistant to CTLA-4 blockade) orthotopic models and demonstrated that CTLA-4 blockade treatment induced gasdermin-mediated pyroptosis of tumor cells, and gasdermin expression positively correlated to the effectiveness of CTLA-4 blockade treatment. We found that CTLA-4 blockade activated CD8+ TĀ cells and increased the levels of interferon Ī³ (IFN-Ī³) and tumor necrosis factor Ī± (TNF-Ī±) cytokines in the tumor microenvironment. These cytokines synergistically activated the STAT1/IRF1 axis to trigger tumor cell pyroptosis and the release of large amounts of inflammatory substances and chemokines. Collectively, our findings revealed that CTLA-4 blockade triggered tumor cells pyroptosis via the release of IFN-Ī³ and TNF-Ī± from activated CD8+ TĀ cells, providing a new perspective of ICB. Copyright Ā© 2023 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.
- Immunology and Microbiology,
- Cancer Research
Inhibition of Microsomal Prostaglandin E2 Synthase Reduces Collagen Deposition in Melanoma Tumors and May Improve Immunotherapy Efficacy by Reducing T-cell Exhaustion.
In Cancer Res Commun on 1 July 2023 by Fukuda, Y., Kim, S. H., et al.
PubMed
The arachidonic acid pathway participates in immunosuppression in various types of cancer. Our previous observation detailed that microsomal prostaglandin E2 synthase 1 (mPGES-1), an enzyme downstream of cyclooxygenase 2 (COX-2), limited antitumor immunity in melanoma; in addition, genetic depletion of mPGES-1 specifically enhanced immune checkpoint blockade therapy. The current study set out to distinguish the roles of mPGES-1 from those of COX-2 in tumor immunity and determine the potential of mPGES-1 inhibitors for reinforcing immunotherapy in melanoma. Genetic deletion of mPGES-1 showed different profiles of prostaglandin metabolites from that of COX-2 deletion. In our syngeneic mouse model, mPGES-1-deficient cells exhibited similar tumorigenicity to that of COX-2-deficient cells, despite a lower ability to suppress PGE2 synthesis by mPGES-1 depletion, indicating the presence of factors other than PGE2 that are likely to regulate tumor immunity. RNA-sequencing analysis revealed that mPGES-1 depletion reduced the expressions of collagen-related genes, which have been found to be associated with immunosuppressive signatures. In our mouse model, collagen was reduced in mPGES-1-deficient tumors, and phenotypic analysis of tumor-infiltrating lymphocytes indicated that mPGES-1-deficient tumors had fewer TIM3+ exhausted CD8+ T cells compared with COX-2-deficient tumors. CAY10678, an mPGES-1 inhibitor, was equivalent to celecoxib, a selective COX-2 inhibitor, in reinforcing anti-PD-1 treatment. Our study indicates that mPGES-1 inhibitors represent a promising adjuvant for immunotherapies in melanoma by reducing collagen deposition and T-cell exhaustion. Collagen is a predominant component of the extracellular matrix that may influence the tumor immune microenvironment for cancer progression. We present here that mPGES-1 has specific roles in regulating tumor immunity, associated with several collagen-related genes and propose that pharmacologic inhibition of mPGES-1 may hold therapeutic promise for improving immune checkpoint-based therapies. Ā© 2023 The Authors; Published by the American Association for Cancer Research.
