InVivoPlus mouse IgG1 isotype control, unknown specificity
Product Details
The MOPC-21 monoclonal antibody is ideal for use as a non-reactive isotype-matched control for mouse IgG1 antibodies in most in vivo and in vitro applications.Specifications
| Isotype | Mouse IgG1,Ā Īŗ |
|---|---|
| Recommended Dilution Buffer | InVivoPure pH 6.5 Dilution Buffer |
| Conjugation | This product is unconjugated. Conjugation is available via our Antibody Conjugation Services. |
| Formulation |
PBS, pH 6.5 Contains no stabilizers or preservatives |
| Aggregation* |
<5% Determined by SEC |
| 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_1107784 |
| Molecular Weight | 150 kDa |
| Murine Pathogen Tests* |
Ectromelia/Mousepox Virus: Negative Hantavirus: Negative K Virus: Negative Lactate Dehydrogenase-Elevating Virus: Negative Lymphocytic Choriomeningitis virus: Negative Mouse Adenovirus: Negative Mouse Cytomegalovirus: Negative Mouse Hepatitis Virus: Negative Mouse Minute Virus: Negative Mouse Norovirus: Negative Mouse Parvovirus: Negative Mouse Rotavirus: Negative Mycoplasma Pulmonis: Negative Pneumonia Virus of Mice: Negative Polyoma Virus: Negative Reovirus Screen: Negative Sendai Virus: Negative Theilerās Murine Encephalomyelitis: Negative |
| Storage | The antibody solution should be stored at the stock concentration at 4Ā°C. Do not freeze. |
Additional Formats
Recommended Products
-
Recommended Dilution Buffer
InVivoPure pH 6.5 Dilution Buffer
Faraco, G., et al. (2018). "Dietary salt promotes neurovascular and cognitive dysfunction through a gut-initiated TH17 response" Nat Neurosci 21(2): 240-249. PubMed
A diet rich in salt is linked to an increased risk of cerebrovascular diseases and dementia, but it remains unclear how dietary salt harms the brain. We report that, in mice, excess dietary salt suppresses resting cerebral blood flow and endothelial function, leading to cognitive impairment. The effect depends on expansion of TH17 cells in the small intestine, resulting in a marked increase in plasma interleukin-17 (IL-17). Circulating IL-17, in turn, promotes endothelial dysfunction and cognitive impairment by the Rho kinase-dependent inhibitory phosphorylation of endothelial nitric oxide synthase and reduced nitric oxide production in cerebral endothelial cells. The findings reveal a new gut-brain axis linking dietary habits to cognitive impairment through a gut-initiated adaptive immune response compromising brain function via circulating IL-17. Thus, the TH17 cell-IL-17 pathway is a putative target to counter the deleterious brain effects induced by dietary salt and other diseases associated with TH17 polarization.
Macal, M., et al. (2018). "Self-Renewal and Toll-like Receptor Signaling Sustain Exhausted Plasmacytoid Dendritic Cells during Chronic Viral Infection" Immunity 48(4): 730-744 e735. PubMed
Although characterization of T cell exhaustion has unlocked powerful immunotherapies, the mechanisms sustaining adaptations of short-lived innate cells to chronic inflammatory settings remain unknown. During murine chronic viral infection, we found that concerted events in bone marrow and spleen mediated by type I interferon (IFN-I) and Toll-like receptor 7 (TLR7) maintained a pool of functionally exhausted plasmacytoid dendritic cells (pDCs). In the bone marrow, IFN-I compromised the number and the developmental capacity of pDC progenitors, which generated dysfunctional pDCs. Concurrently, exhausted pDCs in the periphery were maintained by self-renewal via IFN-I- and TLR7-induced proliferation of CD4(-) subsets. On the other hand, pDC functional loss was mediated by TLR7, leading to compromised IFN-I production and resistance to secondary infection. These findings unveil the mechanisms sustaining a self-perpetuating pool of functionally exhausted pDCs and provide a framework for deciphering long-term exhaustion of other short-lived innate cells during chronic inflammation.
Manlove, L. S., et al. (2015). "Adaptive Immunity to Leukemia Is Inhibited by Cross-Reactive Induced Regulatory T Cells" J Immunol . PubMed
BCR-ABL+ acute lymphoblastic leukemia patients have transient responses to current therapies. However, the fusion of BCR to ABL generates a potential leukemia-specific Ag that could be a target for immunotherapy. We demonstrate that the immune system can limit BCR-ABL+ leukemia progression although ultimately this immune response fails. To address how BCR-ABL+ leukemia escapes immune surveillance, we developed a peptide: MHC class II tetramer that labels endogenous BCR-ABL-specific CD4+ T cells. Naive mice harbored a small population of BCR-ABL-specific T cells that proliferated modestly upon immunization. The small number of naive BCR-ABL-specific T cells was due to negative selection in the thymus, which depleted BCR-ABL-specific T cells. Consistent with this observation, we saw that BCR-ABL-specific T cells were cross-reactive with an endogenous peptide derived from ABL. Despite this cross-reactivity, the remaining population of BCR-ABL reactive T cells proliferated upon immunization with the BCR-ABL fusion peptide and adjuvant. In response to BCR-ABL+ leukemia, BCR-ABL-specific T cells proliferated and converted into regulatory T (Treg) cells, a process that was dependent on cross-reactivity with self-antigen, TGF-beta1, and MHC class II Ag presentation by leukemic cells. Treg cells were critical for leukemia progression in C57BL/6 mice, as transient Treg cell ablation led to extended survival of leukemic mice. Thus, BCR-ABL+ leukemia actively suppresses antileukemia immune responses by converting cross-reactive leukemia-specific T cells into Treg cells.
Sell, S., et al. (2015). "Control of murine cytomegalovirus infection by gammadelta T cells" PLoS Pathog 11(2): e1004481. PubMed
Infections with cytomegalovirus (CMV) can cause severe disease in immunosuppressed patients and infected newborns. Innate as well as cellular and humoral adaptive immune effector functions contribute to the control of CMV in immunocompetent individuals. None of the innate or adaptive immune functions are essential for virus control, however. Expansion of gammadelta T cells has been observed during human CMV (HCMV) infection in the fetus and in transplant patients with HCMV reactivation but the protective function of gammadelta T cells under these conditions remains unclear. Here we show for murine CMV (MCMV) infections that mice that lack CD8 and CD4 alphabeta-T cells as well as B lymphocytes can control a MCMV infection that is lethal in RAG-1(-/-) mice lacking any T- and B-cells. gammadelta T cells, isolated from infected mice can kill MCMV infected target cells in vitro and, importantly, provide long-term protection in infected RAG-1(-/-) mice after adoptive transfer. gammadelta T cells in MCMV infected hosts undergo a prominent and long-lasting phenotypic change most compatible with the view that the majority of the gammadelta T cell population persists in an effector/memory state even after resolution of the acute phase of the infection. A clonotypically focused Vgamma1 and Vgamma2 repertoire was observed at later stages of the infection in the organs where MCMV persists. These findings add gammadelta T cells as yet another protective component to the anti-CMV immune response. Our data provide clear evidence that gammadelta T cells can provide an effective control mechanism of acute CMV infections, particularly when conventional adaptive immune mechanisms are insufficient or absent, like in transplant patient or in the developing immune system in utero. The findings have implications in the stem cell transplant setting, as antigen recognition by gammadelta T cells is not MHC-restricted and dual reactivity against CMV and tumors has been described.
Leon, B., et al. (2014). "FoxP3+ regulatory T cells promote influenza-specific Tfh responses by controlling IL-2 availability" Nat Commun 5: 3495. PubMed
Here, we test the role of FoxP3(+) regulatory T cells (Tregs) in controlling T follicular helper (Tfh) and germinal centre (GC) B-cell responses to influenza. In contrast to the idea that Tregs suppress T-cell responses, we find that Treg depletion severely reduces the Tfh cell response to influenza virus. Furthermore, Treg depletion prevents the accumulation of influenza-specific GCs. These effects are not due to alterations in TGFbeta availability or a precursor-progeny relationship between Tregs and Tfh cells, but are instead mediated by increased availability of IL-2, which suppresses the differentiation of Tfh cells and as a consequence, compromises the GC B response. Thus, Tregs promote influenza-specific GC responses by preventing excessive IL-2 signalling, which suppresses Tfh cell differentiation.
Beug, S. T., et al. (2014). "Smac mimetics and innate immune stimuli synergize to promote tumor death" Nat Biotechnol 32(2): 182-190. PubMed
Smac mimetic compounds (SMC), a class of drugs that sensitize cells to apoptosis by counteracting the activity of inhibitor of apoptosis (IAP) proteins, have proven safe in phase 1 clinical trials in cancer patients. However, because SMCs act by enabling transduction of pro-apoptotic signals, SMC monotherapy may be efficacious only in the subset of patients whose tumors produce large quantities of death-inducing proteins such as inflammatory cytokines. Therefore, we reasoned that SMCs would synergize with agents that stimulate a potent yet safe ācytokine storm.ā Here we show that oncolytic viruses and adjuvants such as poly(I:C) and CpG induce bystander death of cancer cells treated with SMCs that is mediated by interferon beta (IFN-beta), tumor necrosis factor alpha (TNF-alpha) and/or TNF-related apoptosis-inducing ligand (TRAIL). This combinatorial treatment resulted in tumor regression and extended survival in two mouse models of cancer. As these and other adjuvants have been proven safe in clinical trials, it may be worthwhile to explore their clinical efficacy in combination with SMCs.
Perng, O. A., et al. (2014). "The degree of CD4+ T cell autoreactivity determines cellular pathways underlying inflammatory arthritis" J Immunol 192(7): 3043-3056. PubMed
Although therapies targeting distinct cellular pathways (e.g., anticytokine versus anti-B cell therapy) have been found to be an effective strategy for at least some patients with inflammatory arthritis, the mechanisms that determine which pathways promote arthritis development are poorly understood. We have used a transgenic mouse model to examine how variations in the CD4(+) T cell response to a surrogate self-peptide can affect the cellular pathways that are required for arthritis development. CD4(+) T cells that are highly reactive with the self-peptide induce inflammatory arthritis that affects male and female mice equally. Arthritis develops by a B cell-independent mechanism, although it can be suppressed by an anti-TNF treatment, which prevented the accumulation of effector CD4(+) Th17 cells in the joints of treated mice. By contrast, arthritis develops with a significant female bias in the context of a more weakly autoreactive CD4(+) T cell response, and B cells play a prominent role in disease pathogenesis. In this setting of lower CD4(+) T cell autoreactivity, B cells promote the formation of autoreactive CD4(+) effector T cells (including Th17 cells), and IL-17 is required for arthritis development. These studies show that the degree of CD4(+) T cell reactivity for a self-peptide can play a prominent role in determining whether distinct cellular pathways can be targeted to prevent the development of inflammatory arthritis.
Vokaer, B., et al. (2013). "IL-17A and IL-2-expanded regulatory T cells cooperate to inhibit Th1-mediated rejection of MHC II disparate skin grafts" PLoS One 8(10): e76040. PubMed
Several evidences suggest that regulatory T cells (Treg) promote Th17 differentiation. Based on this hypothesis, we tested the effect of IL-17A neutralization in a model of skin transplantation in which long-term graft survival depends on a strong in vivo Treg expansion induced by transient exogenous IL-2 administration. As expected, IL-2 supplementation prevented rejection of MHC class II disparate skin allografts but, surprisingly, not in IL-17A-deficient recipients. We attested that IL-17A was not required for IL-2-mediated Treg expansion, intragraft recruitment or suppressive capacities. Instead, IL-17A prevented allograft rejection by inhibiting Th1 alloreactivity independently of Tregs. Indeed, T-bet expression of naive alloreactive CD4+ T cells and the subsequent Th1 immune response was significantly enhanced in IL-17A deficient mice. Our results illustrate for the first time a protective role of IL-17A in CD4+-mediated allograft rejection process.
Kerzerho, J., et al. (2013). "Programmed cell death ligand 2 regulates TH9 differentiation and induction of chronic airway hyperreactivity" J Allergy Clin Immunol 131(4): 1048-1057, 1057 e1041-1042. PubMed
BACKGROUND: Asthma is defined as a chronic inflammatory disease of the airways; however, the underlying physiologic and immunologic processes are not fully understood. OBJECTIVE: The aim of this study was to determine whether TH9 cells develop in vivo in a model of chronic airway hyperreactivity (AHR) and what factors control this development. METHOD: We have developed a novel chronic allergen exposure model using the clinically relevant antigen Aspergillus fumigatus to determine the time kinetics of TH9 development in vivo. RESULTS: TH9 cells were detectable in the lungs after chronic allergen exposure. The number of TH9 cells directly correlated with the severity of AHR, and anti-IL-9 treatment decreased airway inflammation. Moreover, we have identified programmed cell death ligand (PD-L) 2 as a negative regulator of TH9 cell differentiation. Lack of PD-L2 was associated with significantly increased TGF-beta and IL-1alpha levels in the lungs, enhanced pulmonary TH9 differentiation, and higher morbidity in the sensitized mice. CONCLUSION: Our findings suggest that PD-L2 plays a pivotal role in the regulation of TH9 cell development in chronic AHR, providing novel strategies for modulating adaptive immunity during chronic allergic responses.
Myles, I. A., et al. (2013). "Signaling via the IL-20 receptor inhibits cutaneous production of IL-1beta and IL-17A to promote infection with methicillin-resistant Staphylococcus aureus" Nat Immunol 14(8): 804-811. PubMed
Staphylococcus aureus causes most infections of human skin and soft tissue and is a major infectious cause of mortality. Host defense mechanisms against S. aureus are incompletely understood. Interleukin 19 (IL-19), IL-20 and IL-24 signal through type I and type II IL-20 receptors and are associated with inflammatory skin diseases such as psoriasis and atopic dermatitis. We found here that those cytokines promoted cutaneous infection with S. aureus in mice by downregulating IL-1beta- and IL-17A-dependent pathways. We noted similar effects of those cytokines in human keratinocytes after exposure to S. aureus, and antibody blockade of the IL-20 receptor improved outcomes in infected mice. Our findings identify an immunosuppressive role for IL-19, IL-20 and IL-24 during infection that could be therapeutically targeted to alter susceptibility to infection.
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.
- Immunology and Microbiology,
MOSPD2 regulates the activation state of Ī±LĪ²2 integrin to control monocyte migration: applicability for treatment of chronic inflammatory diseases.
In Immunol Res on 1 May 2025 by Salem, Y., Yacov, N., et al.
PubMed
Monocytes are innate immune cells that drive the chronicity of various inflammatory diseases. Monocyte migration to inflamed tissues involves multiple steps of interaction with the vascular endothelium and the extracellular matrix (ECM), a process mediated through conformational transitions in cell surface integrins. We previously described motile sperm domain-containing protein 2 (MOSPD2) as a surface protein expressed on myeloid cells that is essential for the migration of monocytes and a key regulator of inflammation. Investigating MOSPD2's mechanism of action, we assessed whether it plays a role in regulating integrin activation and monocyte adhesion. Data show that silencing of MOSPD2 expression in the THP-1 monocytic cell line significantly increased cell adhesion to various ECM molecules. Employing IW-601, a humanized anti-human MOSDP2 monoclonal antibody, on primary human monocytes increased adhesion to ECM molecules as well as to adhesion molecules. At the molecular level, silencing of MOSPD2 or blocking MOSPD2 using IW-601 led to a transition in integrin Ī±LĪ²2 (CD11a/CD18, LFA-1) conformation into an active high-affinity binding form and to the induction of adhesion-associated signaling pathways. Co-immunoprecipitation experiments showed that MOSPD2 binds integrin-Ī²2 (CD18), but not integrin-Ī²1 (CD29). Our results reveal a novel mechanism controlling monocyte migration, in which MOSPD2 acts as an adhesion checkpoint that governs the balance between monocyte adhesion and release. By demonstrating the inhibitory effect of IW-601 on the migration of primary monocytes isolated from patients with chronic inflammatory diseases, we provide proof of concept for translating MOSPD2's mechanism into a potential treatment for inflammatory diseases, further supported by in vivo data in models of RA and IBD.
- Cancer Research,
- Immunology and Microbiology
Identification of a conserved subset of cold tumors responsive to immune checkpoint blockade.
In J Immunother Cancer on 6 March 2025 by Moore, J., Gkantalis, J., et al.
PubMed
The efficacy of immune checkpoint blockade (ICB) depends on restoring immune recognition of cancer cells that have evaded immune surveillance. Transforming growth factor-beta (TGFĪ²) is associated with immune-poor, so-called cold tumors whereas loss of its signaling promotes DNA misrepair that could stimulate immune response.
- Cancer Research
Semaphorin7A and PD-L1 cooperatively drive immunosuppression during mammary involution and breast cancer
In bioRxiv on 4 January 2025 by Elder, A. M., Fairchild, H. R., et al.
- Immunology and Microbiology
High PD-1 and CTLA-4 expression correlates with host immune suppression in patients and a mouse model infected with Echinococcus multilocularis.
In Parasit Vectors on 25 October 2024 by Sun, T., Yang, Y., et al.
PubMed
Alveolar echinococcosis (AE), a fatal disease caused by Echinococcus multilocularis, often affects the liver, with tumor-like growth. However, the mechanism by which E. multilocularis evades host immune surveillance remains unclear.
- Immunology and Microbiology
PD-L1 restrains PD-1+Nrp1lo Treg cells to suppress inflammation-driven colorectal tumorigenesis.
In Cell Rep on 22 October 2024 by Poschel, D. B., Klement, J. D., et al.
PubMed
T cells function not only as an essential component of host cancer immunosurveillance but also as a regulator of colonic inflammation, a process that promotes colorectal cancer. Programmed death-ligand 1 (PD-L1) is a TĀ cell-negative regulator, but its role in regulation of TĀ cell functions in the context of colorectal cancer is unknown. We report that global deletion of Cd274 results in increased colonic inflammation, PD-1+ TĀ cells, and inflammation-driven colorectal tumorigenesis in mice. Single-cell RNA sequencing (scRNA-seq) analysis revealed that PD-L1 suppresses subpopulations of programmed cell death protein 1 (PD-1)+Nrp1lo regulatory T (Treg) cells and interleukin (IL) 6+ neutrophils in colorectal tumor. Treg cells produce transforming growth factor (TGF) Ī² to recruit IL6+ neutrophils. Neutrophils produce IL6 to inhibit activation of tumor-specific cytotoxic T lymphocytes (CTLs) and primary CTLs. Accordingly, IL6 blockade immunotherapy increases CTL activation and suppresses colon tumor growth inĀ vivo. Our findings determine that PD-L1 restrains PD-1+Nrp1loTGFĪ²+ Treg cells to suppress IL6+ neutrophil tumor recruitment to sustain CTL activation to control inflammation-driven colorectal tumorigenesis.
- Cancer Research,
- Immunology and Microbiology
In vivoimaging of T-cell coregulator B7-H4 reveals protumor macrophage status in prostate cancer
In bioRxiv on 30 September 2024 by Kumar, M., Singh, S. B., et al.
- Biochemistry and Molecular biology
Standardized Production of Anti-Desmoglein 3 Antibody AK23 for Translational Pemphigus Vulgaris Research.
In Curr Protoc on 1 August 2024 by Mueller, E. J., Rahimi, S., et al.
PubMed
Antibody-mediated receptor activation is successfully used to develop medical treatments. If the activation induces a pathological response, such antibodies are also excellent tools for defining molecular mechanisms of target receptor malfunction and designing rescue therapies. Prominent examples are naturally occurring autoantibodies inducing the severe blistering disease pemphigus vulgaris (PV). In the great majority of patients, the antibodies bind to the adhesion receptor desmoglein 3 (Dsg3) and interfere with cell signaling to provoke severe blistering in the mucous membranes and/or skin. The identification of a comprehensive causative signaling network downstream of antibody-targeted Dsg3 receptors (e.g., shown by pharmacological activators or inhibitors) is currently being discussed as a basis to develop urgently needed first-line treatments for PV patients. Although polyclonal PV IgG antibodies have been used as proof of principle for pathological signal activation, monospecific anti-Dsg3 antibodies are necessary and have been developed to identify pathological Dsg3 receptor-mediated signal transduction. The experimental monospecific PV antibody AK23, produced from hybridoma cells, was extensively tested in our laboratory in both in vitro and in vivo models for PV and proved to recapitulate the clinicopathological features of PV when generated using the standardized production and purification protocols described herein. Ā© 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Bovine IgG stripping from FBS and quality control Basic Protocol 2: AK23 hybridoma expansion and IgG production Basic Protocol 3: AK23 IgG purification Basic Protocol 4: AK23 IgG quality control Support Protocol 1: Detection of endotoxin levels Support Protocol 2: Detection and removal of mycoplasma.
- Cancer Research,
- Immunology and Microbiology
EGFR mutations induce the suppression of CD8+ T cell and anti-PD-1 resistance via ERK1/2-p90RSK-TGF-Ī² axis in non-small cell lung cancer.
In J Transl Med on 14 July 2024 by Huang, H., Zhu, X., et al.
PubMed
Non-small cell lung cancer (NSCLC) patients with EGFR mutations exhibit an unfavorable response to immune checkpoint inhibitor (ICI) monotherapy, and their tumor microenvironment (TME) is usually immunosuppressed. TGF-Ī² plays an important role in immunosuppression; however, the effects of TGF-Ī² on the TME and the efficacy of anti-PD-1 immunotherapy against EGFR-mutated tumors remain unclear.
- Cancer Research,
- Immunology and Microbiology
Lack of TGFĪ² signaling competency predicts immune poor cancer conversion to immune rich and response to checkpoint blockade
In bioRxiv on 8 March 2024 by Moore, J., Gkantalis, J., et al.
- Cardiovascular biology,
- Genetics
Disruption of the Uty epigenetic regulator locus in hematopoietic cells phenocopies the profibrotic attributes of Y chromosome loss in heart failure.
In Nat Cardiovasc Res on 1 March 2024 by Horitani, K., Chavkin, N., et al.
PubMed
Heart failure affects millions of people worldwide, with men exhibiting a higher incidence than women. Our previous work has shown that mosaic loss of the Y chromosome (LOY) in leukocytes is causally associated with an increased risk for heart failure. Here, we show that LOY macrophages from the failing hearts of humans with dilated cardiomyopathy exhibit widespread changes in gene expression that correlate with cardiac fibroblast activation. Moreover, we identify the ubiquitously transcribed t et ratricopeptide Y-linked (Uty) gene in leukocytes as a causal locus for an accelerated progression of heart failure in male mice with LOY. We demonstrate that Uty disruption leads to epigenetic alterations in both monocytes and macrophages, increasing the propensity of differentiation into profibrotic macrophages. Treatment with a transforming growth factor-Ī²-neutralizing antibody prevented the cardiac pathology associated with Uty deficiency in leukocytes. These findings shed light on the mechanisms that contribute to the higher incidence of heart failure in men.
- Immunology and Microbiology,
- Neuroscience
APOE4 impairs the microglial response in Alzheimer's disease by inducing TGFĪ²-mediated checkpoints.
In Nat Immunol on 1 November 2023 by Yin, Z., Rosenzweig, N., et al.
PubMed
The APOE4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease (AD). The contribution of microglial APOE4 to AD pathogenesis is unknown, although APOE has the most enriched gene expression in neurodegenerative microglia (MGnD). Here, we show in mice and humans a negative role of microglial APOE4 in the induction of the MGnD response to neurodegeneration. Deletion of microglial APOE4 restores the MGnD phenotype associated with neuroprotection in P301S tau transgenic mice and decreases pathology in APP/PS1 mice. MGnD-astrocyte cross-talk associated with Ī²-amyloid (AĪ²) plaque encapsulation and clearance are mediated via LGALS3 signaling following microglial APOE4 deletion. In the brains of AD donors carrying the APOE4 allele, we found a sex-dependent reciprocal induction of AD risk factors associated with suppression of MGnD genes in females, including LGALS3, compared to individuals homozygous for the APOE3 allele. Mechanistically, APOE4-mediated induction of ITGB8-transforming growth factor-Ī² (TGFĪ²) signaling impairs the MGnD response via upregulation of microglial homeostatic checkpoints, including Inpp5d, in mice. Deletion of Inpp5d in microglia restores MGnD-astrocyte cross-talk and facilitates plaque clearance in APP/PS1 mice. We identify the microglial APOE4-ITGB8-TGFĪ² pathway as a negative regulator of microglial response to AD pathology, and restoring the MGnD phenotype via blocking ITGB8-TGFĪ² signaling provides a promising therapeutic intervention for AD.
Anti-S100A4 antibody administration alleviates bronchial epithelial-mesenchymal transition in asthmatic mice.
In Open Med (Wars) on 24 October 2023 by Liu, S., Liu, M., et al.
PubMed
We elucidated the effect of S100A4 on airway remodeling by regulating airway inflammation and epithelial-mesenchymal transition (EMT) in mouse models of asthma. Asthmatic mouse models were established by sensitization and challenged with ovalbumin (OVA). Anti-S100A4 antibody or control IgG antibody was administered daily before the OVA challenge. After the last challenge, airway inflammation and airway hyperresponsiveness were measured; lung tissues and bronchoalveolar lavage fluid (BALF) were harvested. Lung tissue sections were stained and evaluated for pathological changes. Levels of inflammatory cytokines were measured using ELISA. Levels of S100A4 and EMT markers were determined via western blotting analysis. Human bronchial epithelial cells were stimulated with 100āmg/mL house dust mites (HDMs) to evaluate the effect of S100A4 downregulation on EMT in vitro. S100A4 was increased in lung tissues and BALF from asthmatic mice. The asthmatic mice presented airway hyperresponsiveness, airway inflammation, and airway remodeling. After anti-S100A4 antibody administration, pathophysiological signs, including airway hyperresponsiveness and increased infiltration of inflammatory cells, were attenuated. Additionally, anti-S100A4 administration downregulated vimentin and Ī±-SMA expression and upregulated E-cadherin expression in OVA-challenged mice. S100A4 downregulation also inhibited EMT process in HDM-stimulated 16HBE cells. Anti-S100A4 antibody administration alters airway remodeling by preventing EMT in mouse models of asthma.
- Cancer Research
TGF-Ī² Type I Receptor Signaling in Melanoma Liver Metastases Increases Metastatic Outgrowth.
In Int J Mol Sci on 12 May 2023 by Marvin, D. L., Dijkstra, J., et al.
PubMed
Despite advances in treatment for metastatic melanoma patients, patients with liver metastasis have an unfavorable prognosis. A better understanding of the development of liver metastasis is needed. The multifunctional cytokine Transforming Growth Factor Ī² (TGF-Ī²) plays various roles in melanoma tumors and metastasis, affecting both tumor cells and cells from the surrounding tumor microenvironment. To study the role of TGF-Ī² in melanoma liver metastasis, we created a model to activate or repress the TGF-Ī² receptor pathway in vitro and in vivo in an inducible manner. For this, we engineered B16F10 melanoma cells to have inducible ectopic expression of a constitutively active (ca) or kinase-inactive (ki) TGF-Ī² receptor I, also termed activin receptor-like kinase (ALK5). In vitro, stimulation with TGF-Ī² signaling and ectopic caALK5 expression reduced B16F10 cell proliferation and migration. Contrasting results were found in vivo; sustained caALK5 expression in B16F10 cells in vivo increased the metastatic outgrowth in liver. Blocking microenvironmental TGF-Ī² did not affect metastatic liver outgrowth of both control and caALK5 expressing B16F10 cells. Upon characterizing the tumor microenvironment of control and caALk5 expressing B16F10 tumors, we observed reduced (cytotoxic) T cell presence and infiltration, as well as an increase in bone marrow-derived macrophages in caALK5 expressing B16F10 tumors. This suggests that caALK5 expression in B16F10 cells induces changes in the tumor microenvironment. A comparison of newly synthesized secreted proteins upon caALK5 expression by B16F10 cells revealed increased secretion of matrix remodeling proteins. Our results show that TGF-Ī² receptor activation in B16F10 melanoma cells can increase metastatic outgrowth in liver in vivo, possibly through remodeling of the tumor microenvironment leading to altered infiltration of immune cells. These results provide insights in the role of TGF-Ī² signaling in B16F10 liver metastasis and could have implications regarding the use of TGF-Ī² inhibitors for the treatment of melanoma patients with liver metastasis.
- Biochemistry and Molecular biology
Blockade of CD47 function attenuates restenosis by promoting smooth muscle cell efferocytosis and inhibiting their migration and proliferation.
In J Biol Chem on 1 April 2023 by Govatati, S., Pichavaram, P., et al.
PubMed
Cluster of differentiation 47 (CD47) plays an important role in the pathophysiology of various diseases including atherosclerosis but its role in neointimal hyperplasia which contributes to restenosis has not been studied. Using molecular approaches in combination with a mouse vascular endothelial denudation model, we studied the role of CD47 in injury-induced neointimal hyperplasia. We determined that thrombin-induced CD47 expression both in human aortic smooth muscle cells (HASMCs) and mouse aortic smooth muscle cells. In exploring the mechanisms, we found that the protease-activated receptor 1-GĪ± protein q/11 (GĪ±q/11)-phospholipase CĪ²3-nuclear factor of activated T cells c1 signaling axis regulates thrombin-induced CD47 expression in HASMCs. Depletion of CD47 levels using its siRNA or interference of its function by its blocking antibody (bAb) blunted thrombin-induced migration and proliferation of HASMCs and mouse aortic smooth muscle cells. In addition, we found that thrombin-induced HASMC migration requires CD47 interaction with integrin Ī²3. On the other hand, thrombin-induced HASMC proliferation was dependent on CD47's role in nuclear export and degradation of cyclin-dependent kinase-interacting protein 1. In addition, suppression of CD47 function by its bAb rescued HASMC efferocytosis from inhibition by thrombin. We also found that vascular injury induces CD47 expression in intimal SMCs and that inhibition of CD47 function by its bAb, while alleviating injury-induced inhibition of SMC efferocytosis, attenuated SMC migration, and proliferation resulting in reduced neointima formation. Thus, these findings reveal a pathological role for CD47 in neointimal hyperplasia.
- In vivo experiments,
- Mus musculus (Mouse),
- Cancer Research
Tumor PD-L1 engages myeloid PD-1 to suppress type I interferon to impair cytotoxic T lymphocyte recruitment.
In Cancer Cell on 13 March 2023 by Klement, J. D., Redd, P. S., et al.
PubMed
The cellular and molecular mechanisms underlying tumor cell PD-L1 (tPD-L1) function in tumor immune evasion are incompletely understood. We report here that tPD-L1 does not suppress cytotoxic T lymphocyte (CTL) activity in co-cultures of tumor cells and tumor-specific CTLs and exhibits no effect on primary tumor growth. However, deleting tPD-L1 decreases lung metastasis in a CTL-dependent manner in tumor-bearing mice. Depletion of myeloid cells or knocking out PD-1 in myeloid cells (mPD-1) impairs tPD-L1 promotion of tumor lung metastasis in mice. Single-cell RNA sequencing (scRNA-seq) reveals that tPD-L1 engages mPD-1 to activate SHP2 to antagonize the type I interferon (IFN-I) and STAT1 pathway to repress Cxcl9 and impair CTL recruitment to lung metastases. Human cancer patient response to PD-1 blockade immunotherapy correlates with IFN-I response in myeloid cells. Our findings determine that tPD-L1 engages mPD-1 to activate SHP2 to suppress the IFN-I-STAT1-CXCL9 pathway to impair CTL tumor recruitment in lung metastasis.
- Cancer Research
Targeting the secreted RGDKGE collagen fragment reduces PDāL1 by a proteasomeādependent mechanism and inhibits tumor growth.
In Oncol Rep on 1 February 2023 by Caron, J. M., Han, X., et al.
PubMed
Structural alterations of collagen impact signaling that helps control tumor progression and the responses to therapeutic intervention. Integrins represent a class of receptors that include members that mediate collagen signaling. However, a strategy of directly targeting integrins to control tumor growth has demonstrated limited activity in the clinical setting. New molecular understanding of integrins have revealed that these receptors can regulate both proā and antiātumorigenic functions in a cell typeādependent manner. Therefore, designing strategies that block proātumorigenic signaling, without impeding antiātumorigenic functions, may lead to development of more effective therapies. In the present study, evidence was provided for a novel signaling cascade in which Ī²3āintegrināmediated binding to a secreted RGDKGEācontaining collagen fragment stimulates an autocrineālike signaling pathway that differentially governs the activity of both YAP and (protein kinaseāA) PKA, ultimately leading to alterations in the levels of immune checkpoint molecule PDāL1 by a proteasome dependent mechanism. Selectively targeting this collagen fragment, reduced nuclear YAP levels, and enhanced PKA and proteasome activity, while also exhibiting significant antitumor activity inĀ vivo. The present findings not only provided new mechanistic insight into a previously unknown autocrineālike signaling pathway that may provide tumor cells with the ability to regulate PDāL1, but our findings may also help in the development of more effective strategies to control proātumorigenic Ī²3āintegrin signaling without disrupting its tumor suppressive functions in other cellular compartments.
- Immunology and Microbiology
Toxin expression during Staphylococcus aureus infection imprints host immunity to inhibit vaccine efficacy.
In NPJ Vaccines on 24 January 2023 by Teymournejad, O., Li, Z., et al.
PubMed
Staphylococcus aureus infections are a major public health issue, and a vaccine is urgently needed. Despite a considerable promise in preclinical models, all vaccines tested thus far have failed to protect humans against S. aureus. Unlike laboratory mice, humans are exposed to S. aureus throughout life. In the current study, we hypothesized that prior exposure to S. aureus "imprints" the immune response to inhibit vaccine-mediated protection. We established a mouse model in which S. aureus skin and soft tissue infection (SSTI) is followed by vaccination and secondary SSTI. Unlike naĆÆve mice, S. aureus-sensitized mice were incompletely protected against secondary SSTI by vaccination with the inactivated Ī±-hemolysin (Hla) mutant HlaH35L. Inhibition of protection was specific for the HlaH35L vaccine and required hla expression during primary SSTI. Surprisingly, inhibition occurred at the level of vaccine-elicited effector T cells; hla expression during primary infection limited the expansion of T cells and dendritic cells and impaired vaccine-specific T cell responses. Importantly, the T cell-stimulating adjuvant CAF01 rescued inhibition and restored vaccine-mediated protection. Together, these findings identify a potential mechanism for the failure of translation of promising S. aureus vaccines from mouse models to clinical practice and suggest a path forward to prevent these devastating infections.
- Cancer Research
Expansion of interferon inducible gene pool via USP18 inhibition promotes cancer cell pyroptosis.
In Nat Commun on 17 January 2023 by Arimoto, K. I., Miyauchi, S., et al.
PubMed
While immunotherapy has emerged as a breakthrough cancer therapy, it is only effective in some patients, indicating the need of alternative therapeutic strategies. Induction of cancer immunogenic cell death (ICD) is one promising way to elicit potent adaptive immune responses against tumor-associated antigens. Type I interferon (IFN) is well known to play important roles in different aspects of immune responses, including modulating ICD in anti-tumor action. However, how to expand IFN effect in promoting ICD responses has not been addressed. Here we show that depletion of ubiquitin specific protease 18 (USP18), a negative regulator of IFN signaling, selectively induces cancer cell ICD. Lower USP18 expression correlates with better survival across human selected cancer types and delays cancer progression in mouse models. Mechanistically, nuclear USP18 controls the enhancer landscape of cancer cells and diminishes STAT2-mediated transcription complex binding to IFN-responsive elements. Consequently, USP18 suppression not only enhances expression of canonical IFN-stimulated genes (ISGs), but also activates the expression of a set of atypical ISGs and NF-ĪŗB target genes, including genes such as Polo like kinase 2 (PLK2), that induce cancer pyroptosis. These findings may support the use of targeting USP18 as a potential cancer immunotherapy.
- COVID-19,
- Immunology and Microbiology
Amphiphile-CpG vaccination induces potent lymph node activation and COVID-19 immunity in mice and non-human primates.
In NPJ Vaccines on 28 October 2022 by Seenappa, L. M., Jakubowski, A., et al.
PubMed
Despite the success of currently authorized vaccines for the reduction of severe COVID-19 disease risk, rapidly emerging viral variants continue to drive pandemic waves of infection, resulting in numerous global public health challenges. Progress will depend on future advances in prophylactic vaccine activity, including advancement of candidates capable of generating more potent induction of cross-reactive T cells and durable cross-reactive antibody responses. Here we evaluated an Amphiphile (AMP) adjuvant, AMP-CpG, admixed with SARS-CoV-2 Spike receptor binding domain (RBD) immunogen, as a lymph node-targeted protein subunit vaccine (ELI-005) in mice and non-human primates (NHPs). AMP-mediated targeting of CpG DNA to draining lymph nodes resulted in comprehensive local immune activation characterized by extensive transcriptional reprogramming, inflammatory proteomic milieu, and activation of innate immune cells as key orchestrators of antigen-directed adaptive immunity. Prime-boost immunization with AMP-CpG in mice induced potent and durable T cell responses in multiple anatomical sites critical for prophylactic efficacy and prevention of severe disease. Long-lived memory responses were rapidly expanded upon re-exposure to antigen. In parallel, RBD-specific antibodies were long-lived, and exhibited cross-reactive recognition of variant RBD. AMP-CpG-adjuvanted prime-boost immunization in NHPs was safe and well tolerated, while promoting multi-cytokine-producing circulating T cell responses cross-reactive across variants of concern (VOC). Expansion of RBD-specific germinal center (GC) B cells in lymph nodes correlated to rapid seroconversion with variant-specific neutralizing antibody responses exceeding those measured in convalescent human plasma. These results demonstrate the promise of lymph-node adjuvant-targeting to coordinate innate immunity and generate robust adaptive responses critical for vaccine efficacy.
Early IL-17A Prevention Rather Than Late IL-17A Neutralization Attenuates Toluene Diisocyanate-Induced Mixed Granulocytic Asthma.
In Allergy Asthma Immunol Res on 1 September 2022 by Chen, S., Yu, L., et al.
PubMed
Interleukin (IL)-17A plays a critical role in the pathogenesis of allergic airway inflammation. Yet, the exact roles of IL-17A in asthma are still controversial. Thus, the aim of this study was to dissect the roles of IL-17A in toluene diisocyanate (TDI)-induced mixed granulocytic asthma and to assess the effects of neutralizing antibody in different effector phases on TDI-induced asthma.
