InVivoMAb anti-mouse CSF1
Product Details
The 5A1 monoclonal antibody reacts with mouse colony stimulating factor 1 (CSF1) also known as macrophage colony-stimulating factor (M-CSF). CSF1 is a hematopoietic growth factor that is expressed by many different cell types including fibroblasts, stromal cells, osteoblasts, activated T cells, macrophages, and B cells. CSF1 plays a role in regulating the proliferation, differentiation and survival of monocytes, macrophages, and bone marrow progenitor cells. CSF1 produced in vessel walls is thought to contribute to the development and progression of atherosclerosis. The 5A1 antibody has been shown to neutralize CSF1 in vivo.Specifications
| Isotype | Rat IgG1, κ |
|---|---|
| Recommended Isotype Control(s) | InVivoMAb rat IgG1 isotype control, anti-horseradish peroxidase |
| Recommended Dilution Buffer | InVivoPure pH 8.0 Dilution Buffer |
| Conjugation | This product is unconjugated. Conjugation is available via our Antibody Conjugation Services. |
| Immunogen | Purified mouse CSF-1 |
| Reported Applications | in vivo CSF1 neutralization |
| Formulation |
PBS, pH 8.0 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 G |
| RRID | AB_10950309 |
| Molecular Weight | 150 kDa |
| Storage | The antibody solution should be stored at the stock concentration at 4°C. Do not freeze. |
Recommended Products
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Recommended Isotype Control(s)
InVivoMAb rat IgG1 isotype control, anti-horseradish peroxidase
-
Recommended Dilution Buffer
InVivoPure pH 8.0 Dilution Buffer
in vivo CSF1 neutralization
Liu, X., et al. (2015). "CD47 blockade triggers T cell-mediated destruction of immunogenic tumors" Nat Med 21(10): 1209-1215. PubMed
Macrophage phagocytosis of tumor cells mediated by CD47-specific blocking antibodies has been proposed to be the major effector mechanism in xenograft models. Here, using syngeneic immunocompetent mouse tumor models, we reveal that the therapeutic effects of CD47 blockade depend on dendritic cell but not macrophage cross-priming of T cell responses. The therapeutic effects of anti-CD47 antibody therapy were abrogated in T cell-deficient mice. In addition, the antitumor effects of CD47 blockade required expression of the cytosolic DNA sensor STING, but neither MyD88 nor TRIF, in CD11c(+) cells, suggesting that cytosolic sensing of DNA from tumor cells is enhanced by anti-CD47 treatment, further bridging the innate and adaptive responses. Notably, the timing of administration of standard chemotherapy markedly impacted the induction of antitumor T cell responses by CD47 blockade. Together, our findings indicate that CD47 blockade drives T cell-mediated elimination of immunogenic tumors.
in vivo CSF1 neutralization
Conde, P., et al. (2015). "DC-SIGN(+) Macrophages Control the Induction of Transplantation Tolerance" Immunity 42(6): 1143-1158. PubMed
Tissue effector cells of the monocyte lineage can differentiate into different cell types with specific cell function depending on their environment. The phenotype, developmental requirements, and functional mechanisms of immune protective macrophages that mediate the induction of transplantation tolerance remain elusive. Here, we demonstrate that costimulatory blockade favored accumulation of DC-SIGN-expressing macrophages that inhibited CD8(+) T cell immunity and promoted CD4(+)Foxp3(+) Treg cell expansion in numbers. Mechanistically, that simultaneous DC-SIGN engagement by fucosylated ligands and TLR4 signaling was required for production of immunoregulatory IL-10 associated with prolonged allograft survival. Deletion of DC-SIGN-expressing macrophages in vivo, interfering with their CSF1-dependent development, or preventing the DC-SIGN signaling pathway abrogated tolerance. Together, the results provide new insights into the tolerogenic effects of costimulatory blockade and identify DC-SIGN(+) suppressive macrophages as crucial mediators of immunological tolerance with the concomitant therapeutic implications in the clinic.
in vivo CSF1 neutralization
Zhu, Y., et al. (2014). "CSF1/CSF1R blockade reprograms tumor-infiltrating macrophages and improves response to T-cell checkpoint immunotherapy in pancreatic cancer models" Cancer Res 74(18): 5057-5069. PubMed
Cancer immunotherapy generally offers limited clinical benefit without coordinated strategies to mitigate the immunosuppressive nature of the tumor microenvironment. Critical drivers of immune escape in the tumor microenvironment include tumor-associated macrophages and myeloid-derived suppressor cells, which not only mediate immune suppression, but also promote metastatic dissemination and impart resistance to cytotoxic therapies. Thus, strategies to ablate the effects of these myeloid cell populations may offer great therapeutic potential. In this report, we demonstrate in a mouse model of pancreatic ductal adenocarcinoma (PDAC) that inhibiting signaling by the myeloid growth factor receptor CSF1R can functionally reprogram macrophage responses that enhance antigen presentation and productive antitumor T-cell responses. Investigations of this response revealed that CSF1R blockade also upregulated T-cell checkpoint molecules, including PDL1 and CTLA4, thereby restraining beneficial therapeutic effects. We found that PD1 and CTLA4 antagonists showed limited efficacy as single agents to restrain PDAC growth, but that combining these agents with CSF1R blockade potently elicited tumor regressions, even in larger established tumors. Taken together, our findings provide a rationale to reprogram immunosuppressive myeloid cell populations in the tumor microenvironment under conditions that can significantly empower the therapeutic effects of checkpoint-based immunotherapeutics.
in vivo CSF1 neutralization
Ruffell, B., et al. (2014). "Macrophage IL-10 blocks CD8+ T cell-dependent responses to chemotherapy by suppressing IL-12 expression in intratumoral dendritic cells" Cancer Cell 26(5): 623-637. PubMed
Blockade of colony-stimulating factor-1 (CSF-1) limits macrophage infiltration and improves response of mammary carcinomas to chemotherapy. Herein we identify interleukin (IL)-10 expression by macrophages as the critical mediator of this phenotype. Infiltrating macrophages were the primary source of IL-10 within tumors, and therapeutic blockade of IL-10 receptor (IL-10R) was equivalent to CSF-1 neutralization in enhancing primary tumor response to paclitaxel and carboplatin. Improved response to chemotherapy was CD8(+) T cell-dependent, but IL-10 did not directly suppress CD8(+) T cells or alter macrophage polarization. Instead, IL-10R blockade increased intratumoral dendritic cell expression of IL-12, which was necessary for improved outcomes. In human breast cancer, expression of IL12A and cytotoxic effector molecules were predictive of pathological complete response rates to paclitaxel.
in vivo CSF1 neutralization
Manthey, C. L., et al. (2009). "JNJ-28312141, a novel orally active colony-stimulating factor-1 receptor/FMS-related receptor tyrosine kinase-3 receptor tyrosine kinase inhibitor with potential utility in solid tumors, bone metastases, and acute myeloid leukemia" Mol Cancer Ther 8(11): 3151-3161. PubMed
There is increasing evidence that tumor-associated macrophages promote the malignancy of some cancers. Colony-stimulating factor-1 (CSF-1) is expressed by many tumors and is a growth factor for macrophages and mediates osteoclast differentiation. Herein, we report the efficacy of a novel orally active CSF-1 receptor (CSF-1R) kinase inhibitor, JNJ-28312141, in proof of concept studies of solid tumor growth and tumor-induced bone erosion. H460 lung adenocarcinoma cells did not express CSF-1R and were not growth inhibited by JNJ-28312141 in vitro. Nevertheless, daily p.o. administration of JNJ-28312141 caused dose-dependent suppression of H460 tumor growth in nude mice that correlated with marked reductions in F4/80(+) tumor-associated macrophages and with increased plasma CSF-1, a possible biomarker of CSF-1R inhibition. Furthermore, the tumor microvasculature was reduced in JNJ-28312141-treated mice, consistent with a role for macrophages in tumor angiogenesis. In separate studies, JNJ-28312141 was compared with zoledronate in a model in which MRMT-1 mammary carcinoma cells inoculated into the tibias of rats led to severe cortical and trabecular bone lesions. Both agents reduced tumor growth and preserved bone. However, JNJ-28312141 reduced the number of tumor-associated osteoclasts superior to zoledronate. JNJ-28312141 exhibited additional activity against FMS-related receptor tyrosine kinase-3 (FLT3). To more fully define the therapeutic potential of this new agent, JNJ-28312141 was evaluated in a FLT3-dependent acute myeloid leukemia tumor xenograft model and caused tumor regression. In summary, this novel CSF-1R/FLT3 inhibitor represents a new agent with potential therapeutic activity in acute myeloid leukemia and in settings where CSF-1-dependent macrophages and osteoclasts contribute to tumor growth and skeletal events.
- Cancer Research,
- Genetics
Uridine-derived ribose fuels glucose-restricted pancreatic cancer.
In Nature on 1 June 2023 by Nwosu, Z. C., Ward, M. H., et al.
PubMed
Pancreatic ductal adenocarcinoma (PDA) is a lethal disease notoriously resistant to therapy1,2. This is mediated in part by a complex tumour microenvironment3, low vascularity4, and metabolic aberrations5,6. Although altered metabolism drives tumour progression, the spectrum of metabolites used as nutrients by PDA remains largely unknown. Here we identified uridine as a fuel for PDA in glucose-deprived conditions by assessing how more than 175 metabolites impacted metabolic activity in 21 pancreatic cell lines under nutrient restriction. Uridine utilization strongly correlated with the expression of uridine phosphorylase 1 (UPP1), which we demonstrate liberates uridine-derived ribose to fuel central carbon metabolism and thereby support redox balance, survival and proliferation in glucose-restricted PDA cells. In PDA, UPP1 is regulated by KRAS-MAPK signalling and is augmented by nutrient restriction. Consistently, tumours expressed high UPP1 compared with non-tumoural tissues, and UPP1 expression correlated with poor survival in cohorts of patients with PDA. Uridine is available in the tumour microenvironment, and we demonstrated that uridine-derived ribose is actively catabolized in tumours. Finally, UPP1 deletion restricted the ability of PDA cells to use uridine and blunted tumour growth in immunocompetent mouse models. Our data identify uridine utilization as an important compensatory metabolic process in nutrient-deprived PDA cells, suggesting a novel metabolic axis for PDA therapy. © 2023. The Author(s).
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
Modular-designed engineered bacteria for precision tumor immunotherapy via spatiotemporal manipulation by magnetic field.
In Nature Communications on 23 March 2023 by Ma, X., Liang, X., et al.
PubMed
Micro-nano biorobots based on bacteria have demonstrated great potential for tumor diagnosis and treatment. The bacterial gene expression and drug release should be spatiotemporally controlled to avoid drug release in healthy tissues and undesired toxicity. Herein, we describe an alternating magnetic field-manipulated tumor-homing bacteria developed by genetically modifying engineered Escherichia coli with Fe3O4@lipid nanocomposites. After accumulating in orthotopic colon tumors in female mice, the paramagnetic Fe3O4 nanoparticles enable the engineered bacteria to receive and convert magnetic signals into heat, thereby initiating expression of lysis proteins under the control of a heat-sensitive promoter. The engineered bacteria then lyse, releasing its anti-CD47 nanobody cargo, that is pre-expressed and within the bacteria. The robust immunogenicity of bacterial lysate cooperates with anti-CD47 nanobody to activate both innate and adaptive immune responses, generating robust antitumor effects against not only orthotopic colon tumors but also distal tumors in female mice. The magnetically engineered bacteria also enable the constant magnetic field-controlled motion for enhanced tumor targeting and increased therapeutic efficacy. Thus, the gene expression and drug release behavior of tumor-homing bacteria can be spatiotemporally manipulated in vivo by a magnetic field, achieving tumor-specific CD47 blockage and precision tumor immunotherapy. © 2023. The Author(s).
- Cancer Research,
- Cell Biology,
- Immunology and Microbiology
The microbiome-derived metabolite TMAO drives immune activation and boosts responses to immune checkpoint blockade in pancreatic cancer.
In Science Immunology on 9 September 2022 by Mirji, G., Worth, A., et al.
PubMed
The composition of the gut microbiome can control innate and adaptive immunity and has emerged as a key regulator of tumor growth, especially in the context of immune checkpoint blockade (ICB) therapy. However, the underlying mechanisms for how the microbiome affects tumor growth remain unclear. Pancreatic ductal adenocarcinoma (PDAC) tends to be refractory to therapy, including ICB. Using a nontargeted, liquid chromatography-tandem mass spectrometry-based metabolomic screen, we identified the gut microbe-derived metabolite trimethylamine N-oxide (TMAO), which enhanced antitumor immunity to PDAC. Delivery of TMAO intraperitoneally or via a dietary choline supplement to orthotopic PDAC-bearing mice reduced tumor growth, associated with an immunostimulatory tumor-associated macrophage (TAM) phenotype, and activated effector T cell response in the tumor microenvironment. Mechanistically, TMAO potentiated the type I interferon (IFN) pathway and conferred antitumor effects in a type I IFN-dependent manner. Delivering TMAO-primed macrophages intravenously produced similar antitumor effects. Combining TMAO with ICB (anti-PD1 and/or anti-Tim3) in a mouse model of PDAC significantly reduced tumor burden and improved survival beyond TMAO or ICB alone. Last, the levels of bacteria containing CutC (an enzyme that generates trimethylamine, the TMAO precursor) correlated with long-term survival in patients with PDAC and improved response to anti-PD1 in patients with melanoma. Together, our study identifies the gut microbial metabolite TMAO as a driver of antitumor immunity and lays the groundwork for potential therapeutic strategies targeting TMAO.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology,
- In Vitro
Spatiotemporal co-dependency between macrophages and exhausted CD8+ T cells in cancer.
In Cancer Cell on 13 June 2022 by Kersten, K., Hu, K. H., et al.
PubMed
T cell exhaustion is a major impediment to antitumor immunity. However, it remains elusive how other immune cells in the tumor microenvironment (TME) contribute to this dysfunctional state. Here, we show that the biology of tumor-associated macrophages (TAMs) and exhausted T cells (Tex) in the TME is extensively linked. We demonstrate that in vivo depletion of TAMs reduces exhaustion programs in tumor-infiltrating CD8+ T cells and reinvigorates their effector potential. Reciprocally, transcriptional and epigenetic profiling reveals that Tex express factors that actively recruit monocytes to the TME and shape their differentiation. Using lattice light sheet microscopy, we show that TAM and CD8+ T cells engage in unique, long-lasting, antigen-specific synaptic interactions that fail to activate T cells but prime them for exhaustion, which is then accelerated in hypoxic conditions. Spatially resolved sequencing supports a spatiotemporal self-enforcing positive feedback circuit that is aligned to protect rather than destroy a tumor. Copyright © 2022 Elsevier Inc. All rights reserved.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
Tumor-derived Jagged1 promotes cancer progression through immune evasion.
In Cell Reports on 8 March 2022 by Meng, J., Jiang, Y. Z., et al.
PubMed
Immune checkpoint inhibitor (ICI) therapy is generating remarkable responses in individuals with cancer, but only a small portion of individuals with breast cancer respond well. Here we report that tumor-derived Jagged1 is a key regulator of the tumor immune microenvironment. Jagged1 promotes tumorigenesis in multiple spontaneous mammary tumor models. Through Jagged1-induced Notch activation, tumor cells increase expression and secretion of multiple cytokines to help recruit macrophages into the tumor microenvironment. Educated macrophages crosstalk with tumor-infiltrating T cells to inhibit T cell proliferation and tumoricidal activity. In individuals with triple-negative breast cancer, a high expression level of Jagged1 correlates with increased macrophage infiltration and decreased T cell activity. Co-administration of an ICI PD-1 antibody with a Notch inhibitor significantly inhibits tumor growth in breast cancer models. Our findings establish a distinct signaling cascade by which Jagged1 promotes adaptive immune evasion of tumor cells and provide several possible therapeutic targets. Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.
- Mus musculus (House mouse)
M-CSF supports medullary erythropoiesis and erythroid iron demand following burn injury through its activity on homeostatic iron recycling.
In Scientific Reports on 24 January 2022 by Noel, J. G., Ramser, S. W., et al.
PubMed
M-CSF receptor signaling supports the development and survival of mononuclear phagocytes and is thought to play a role in post burn anemia by promoting myeloid lineage bias. We found M-CSF secretion was increased in burn patients and a murine model of post burn ACI, so we neutralized M-CSF in ACI mice to determine if erythropoiesis was improved. Instead, M-CSF blockade further impaired erythropoiesis and erythroid cells access to iron. M-CSF blockade enhanced inflammatory cytokine secretion, further increased systemic neutrophil counts, and led to tissue iron sequestration that was dependent, in part, on augmented IL-6 secretion which induced hepcidin. Deleterious effects of post burn M-CSF blockade were associated with arrest of an iron recycling gene expression signature in the liver and spleen that included Spi-C transcription factor and heme oxygenase-1, which promote heme metabolism and confer a non-inflammatory tone in macrophages. Hepatic induction of these factors in ACI mice was consistent with a recovery of ferroportin gene expression and reflected an M-CSF dependent expansion and differentiation of Spi-C+ monocytes into Kupffer cells. Together, this data indicates M-CSF secretion supports a homeostatic iron recycling program that plays a key role in the maintenance of erythroid cells access to iron following burn injury. © 2022. The Author(s).
- Mus musculus (House mouse),
- Cancer Research
Prevotellaceae produces butyrate to alleviate PD-1/PD-L1 inhibitor-related cardiotoxicity via PPARα-CYP4X1 axis in colonic macrophages.
In Journal of Experimental & Clinical Cancer Research : CR on 3 January 2022 by Chen, Y., Liu, Y., et al.
PubMed
Immune checkpoint inhibitor-related cardiotoxicity is one of the most lethal adverse effects, and thus, the identification of underlying mechanisms for developing strategies to overcome it has clinical importance. This study aimed to investigate whether microbiota-host interactions contribute to PD-1/PD-L1 inhibitor-related cardiotoxicity. A mouse model of immune checkpoint inhibitor-related cardiotoxicity was constructed by PD-1/PD-L1 inhibitor BMS-1 (5 and 10 mg/kg), and cardiomyocyte apoptosis and cardiotoxicity were determined by hematoxylin and eosin, Masson's trichome and TUNEL assays. 16S rRNA sequencing was used to define the gut microbiota composition. Gut microbiota metabolites short-chain fatty acids (SCFAs) were determined by HPLC. The serum levels of myocardial enzymes (creatine kinase, aspartate transaminase, creatine kinase-MB and lactate dehydrogenase) and the production of M1 factors (TNF-α and IL-1β) were measured by ELISA. The colonic macrophage phenotype was measured by mmunofluorescence and qPCR. The expression of Claudin-1, Occludin, ZO-1 and p-p65 was measured by western blot. The gene expression of peroxisome proliferator-activated receptor α (PPARα) and cytochrome P450 (CYP) 4X1 was determined using qPCR. Statistical analyses were performed using Student's t-test for two-group comparisons, and one-way ANOVA followed by Student-Newman-Keul test for multiple-group comparisons. We observed intestinal barrier injury and gut microbiota dysbiosis characterized by Prevotellaceae and Rikenellaceae genus depletion and Escherichia-Shigella and Ruminococcaceae genus enrichment, accompanied by low butyrate production and M1-like polarization of colonic macrophages in BMS-1 (5 and 10 mg/kg)-induced cardiotoxicity. Fecal microbiota transplantation mirrored the effect of BMS-1 on cardiomyocyte apoptosis and cardiotoxicity, while macrophage depletion and neutralization of TNF-α and IL-1β greatly attenuated BMS-1-induced cardiotoxicity. Importantly, Prevotella loescheii recolonization and butyrate supplementation alleviated PD-1/PD-L1 inhibitor-related cardiotoxicity. Mechanistically, gut microbiota dysbiosis promoted M1-like polarization of colonic macrophages and the production of proinflammatory factors TNF-α and IL-1β through downregulation of PPARα-CYP4X1 axis. Intestinal barrier dysfunction amplifies PD-1/PD-L1 inhibitor-related cardiotoxicity by upregulating proinflammatory factors TNF-α and IL-1β in colonic macrophages via downregulation of butyrate-PPARα-CYP4X1 axis. Thus, targeting gut microbiota to polarize colonic macrophages away from the M1-like phenotype could provide a potential therapeutic strategy for PD-1/PD-L1 inhibitor-related cardiotoxicity. © 2021. The Author(s).
- Cancer Research,
- Immunology and Microbiology
Macrophage-Derived Cholesterol Contributes to Therapeutic Resistance in Prostate Cancer.
In Cancer Research on 1 November 2021 by El-Kenawi, A., Dominguez-Viqueira, W., et al.
PubMed
Castration-resistant prostate cancer (CRPC) is a lethal stage of disease in which androgen receptor (AR) signaling is persistent despite androgen deprivation therapy (ADT). Most studies have focused on investigating cell-autonomous alterations in CRPC, while the contributions of the tumor microenvironment are less well understood. Here we sought to determine the role of tumor-associated macrophages in CRPC, based upon their role in cancer progression and therapeutic resistance. In a syngeneic model that reflected the mutational landscape of CRPC, macrophage depletion resulted in a reduced transcriptional signature for steroid and bile acid synthesis, indicating potential perturbation of cholesterol metabolism. As cholesterol is the precursor of the five major types of steroid hormones, we hypothesized that macrophages were regulating androgen biosynthesis within the prostate tumor microenvironment. Macrophage depletion reduced androgen levels within prostate tumors and restricted AR nuclear localization in vitro and in vivo. Macrophages were also cholesterol-rich and were able to transfer cholesterol to tumor cells in vitro. AR nuclear translocation was inhibited by activation of liver X receptor (LXR)-β, the master regulator of cholesterol homeostasis. Consistent with these data, macrophage depletion extended survival during ADT and the presence of macrophages correlated with therapeutic resistance in patient-derived explants. Taken together, these findings support the therapeutic targeting of macrophages in CRPC. SIGNIFICANCE: These results suggest that macrophage-targeted therapies can be combined with androgen deprivation therapy to treat patients with prostate cancer by limiting cholesterol bioavailability and the production of intratumoral androgens.See related commentary by Al-Janabi and Lewis, p. 5399. ©2021 American Association for Cancer Research.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology,
- In Vitro
Activating a collaborative innate-adaptive immune response to control metastasis.
In Cancer Cell on 11 October 2021 by Sun, L., Kees, T., et al.
PubMed
Tumor-associated macrophages (TAMs) promote metastasis and inhibit T cells, but macrophages can be polarized to kill cancer cells. Macrophage polarization could thus be a strategy for controlling cancer. We show that macrophages from metastatic pleural effusions of breast cancer patients can be polarized to kill cancer cells with monophosphoryl lipid A (MPLA) and interferon (IFN) γ. MPLA + IFNγ injected intratumorally or intraperitoneally reduces primary tumor growth and metastasis in breast cancer mouse models, suppresses metastasis, and enhances chemotherapy response in an ovarian cancer model. Both macrophages and T cells are critical for the treatment's anti-metastatic effects. MPLA + IFNγ stimulates type I IFN signaling, reprograms CD206+ TAMs to inducible NO synthase (iNOS)+ macrophages, and activates cytotoxic T cells through macrophage-secreted interleukin-12 (IL-12) and tumor necrosis factor alpha (TNFα). MPLA and IFNγ are used individually in clinical practice and together represent a previously unexplored approach for engaging a systemic anti-tumor immune response. Copyright © 2021 Elsevier Inc. All rights reserved.
- Immunology and Microbiology,
- Neuroscience
CSF-1 maintains pathogenic but not homeostatic myeloid cells in the central nervous system during autoimmune neuroinflammation
Preprint on BioRxiv : the Preprint Server for Biology on 24 October 2020 by Hwang, D., Seyedsadr, M. S., et al.
PubMed
h4>ABSTRACT/h4> The receptor for colony stimulating factor 1 (CSF-1R) is important for the survival and function of myeloid cells that mediate pathology during experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). CSF-1 and IL-34, the ligands of CSF-1R, have similar bioactivities but distinct tissue and context-dependent expression patterns, suggesting that they have different roles. This could be the case in EAE, given that CSF-1 expression is upregulated in the CNS, while IL-34 remains constitutively expressed. We found that targeting CSF-1 with neutralizing mAb halted ongoing EAE, with efficacy superior to CSF-1R inhibitor BLZ945, whereas IL-34 neutralization had no effect, suggesting that pathogenic myeloid cells were maintained by CSF-1, not IL-34. Both anti-CSF-1- and BLZ945-treatment greatly reduced numbers of monocyte-derived cells and microglia in the CNS. However, anti-CSF-1 selectively depleted inflammatory microglia and monocytes in inflamed CNS areas, whereas BLZ945 depleted virtually all myeloid cells, including quiescent microglia, throughout the CNS. Anti-CSF-1 treatments reduced the size of demyelinated lesions, and microglial activation in the grey matter. Lastly, we found that bone marrow-derived immune cells were the major mediators of CSF-1R-dependent pathology, while microglia played a lesser role. Our findings suggest that targeting CSF-1 could be effective in ameliorating MS pathology, while preserving the homeostatic functions of myeloid cells, thereby minimizing risks associated with total ablation of CSF-1R-dependent cells. h4>Significance Statement/h4> Multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE), are autoimmune diseases characterized by accumulation of myeloid immune cells into the central nervous system (CNS). Both harmful and beneficial myeloid cells are present in EAE/MS, and a goal of MS therapy is to preferentially remove harmful myeloid cells. The receptor for CSF-1 (CSF-1R) is found on myeloid cells and it is important for their survival. CSF-1R can bind two ligands, CSF-1 and IL-34, but is unknown whether their functions in EAE/MS differ. We found that blocking CSF-1 depleted only harmful myeloid cells in the CNS and suppressed EAE, whereas blocking IL-34 had no effect. Thus, we propose that blocking CSF-1 could be a novel therapy for MS.
- Cancer Research,
- Immunology and Microbiology
PPARα Inhibition Overcomes Tumor-Derived Exosomal Lipid-Induced Dendritic Cell Dysfunction.
In Cell Reports on 20 October 2020 by Yin, X., Zeng, W., et al.
PubMed
Dendritic cells (DCs) orchestrate the initiation, programming, and regulation of anti-tumor immune responses. Emerging evidence indicates that the tumor microenvironment (TME) induces immune dysfunctional tumor-infiltrating DCs (TIDCs), characterized with both increased intracellular lipid content and mitochondrial respiration. The underlying mechanism, however, remains largely unclear. Here, we report that fatty acid-carrying tumor-derived exosomes (TDEs) induce immune dysfunctional DCs to promote immune evasion. Mechanistically, peroxisome proliferator activated receptor (PPAR) α responds to the fatty acids delivered by TDEs, resulting in excess lipid droplet biogenesis and enhanced fatty acid oxidation (FAO), culminating in a metabolic shift toward mitochondrial oxidative phosphorylation, which drives DC immune dysfunction. Genetic depletion or pharmacologic inhibition of PPARα effectively attenuates TDE-induced DC-based immune dysfunction and enhances the efficacy of immunotherapy. This work uncovers a role for TDE-mediated immune modulation in DCs and reveals that PPARα lies at the center of metabolic-immune regulation of DCs, suggesting a potential immunotherapeutic target. Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.
- Mus musculus (House mouse),
- Cardiovascular biology
A spatially restricted fibrotic niche in pulmonary fibrosis is sustained by M-CSF/M-CSFR signalling in monocyte-derived alveolar macrophages.
In The European Respiratory Journal on 1 January 2020 by Joshi, N., Watanabe, S., et al.
PubMed
Ontologically distinct populations of macrophages differentially contribute to organ fibrosis through unknown mechanisms.We applied lineage tracing, single-cell RNA sequencing and single-molecule fluorescence in situ hybridisation to a spatially restricted model of asbestos-induced pulmonary fibrosis.We demonstrate that tissue-resident alveolar macrophages, tissue-resident peribronchial and perivascular interstitial macrophages, and monocyte-derived alveolar macrophages are present in the fibrotic niche. Deletion of monocyte-derived alveolar macrophages but not tissue-resident alveolar macrophages ameliorated asbestos-induced lung fibrosis. Monocyte-derived alveolar macrophages were specifically localised to fibrotic regions in the proximity of fibroblasts where they expressed molecules known to drive fibroblast proliferation, including platelet-derived growth factor subunit A. Using single-cell RNA sequencing and spatial transcriptomics in both humans and mice, we identified macrophage colony-stimulating factor receptor (M-CSFR) signalling as one of the novel druggable targets controlling self-maintenance and persistence of these pathogenic monocyte-derived alveolar macrophages. Pharmacological blockade of M-CSFR signalling led to the disappearance of monocyte-derived alveolar macrophages and ameliorated fibrosis.Our findings suggest that inhibition of M-CSFR signalling during fibrosis disrupts an essential fibrotic niche that includes monocyte-derived alveolar macrophages and fibroblasts during asbestos-induced fibrosis. Copyright ©ERS 2020.
- Cancer Research,
- Immunology and Microbiology
Specific targeting of CD163+ TAMs mobilizes inflammatory monocytes and promotes T cell-mediated tumor regression.
In The Journal of Experimental Medicine on 7 October 2019 by Etzerodt, A., Tsalkitzi, K., et al.
PubMed
Tumor-associated macrophages (TAMs) play critical roles in tumor progression but are also capable of contributing to antitumor immunity. Recent studies have revealed an unprecedented heterogeneity among TAMs in both human cancer and experimental models. Nevertheless, we still understand little about the contribution of different TAM subsets to tumor progression. Here, we demonstrate that CD163-expressing TAMs specifically maintain immune suppression in an experimental model of melanoma that is resistant to anti-PD-1 checkpoint therapy. Specific depletion of the CD163+ macrophages results in a massive infiltration of activated T cells and tumor regression. Importantly, the infiltration of cytotoxic T cells was accompanied by the mobilization of inflammatory monocytes that significantly contributed to tumor regression. Thus, the specific targeting of CD163+ TAMs reeducates the tumor immune microenvironment and promotes both myeloid and T cell-mediated antitumor immunity, illustrating the importance of selective targeting of tumor-associated myeloid cells in a therapeutic context. © 2019 Etzerodt et al.
- Immunology and Microbiology
High-dimensional analysis reveals a pathogenic role of inflammatory monocytes in experimental diffuse alveolar hemorrhage.
In JCI Insight on 8 August 2019 by Lee, P. Y., Nelson-Maney, N., et al.
PubMed
Diffuse alveolar hemorrhage (DAH) is a life-threatening pulmonary complication associated with systemic lupus erythematosus, vasculitis, and stem cell transplant. Little is known about the pathophysiology of DAH, and no targeted therapy is currently available. Pristane treatment in mice induces systemic autoimmunity and lung hemorrhage that recapitulates hallmark pathologic features of human DAH. Using this experimental model, we performed high-dimensional analysis of lung immune cells in DAH by mass cytometry and single-cell RNA sequencing. We found a large influx of myeloid cells to the lungs in DAH and defined the gene expression profile of infiltrating monocytes. Bone marrow-derived inflammatory monocytes actively migrated to the lungs and homed adjacent to blood vessels. Using 3 models of monocyte deficiency and complementary transfer studies, we established a central role of inflammatory monocytes in the development of DAH. We further found that the myeloid transcription factor interferon regulatory factor 8 is essential to the development of both DAH and type I interferon-dependent autoimmunity. These findings collectively reveal monocytes as a potential treatment target in DAH.
- Cancer Research,
- Immunology and Microbiology
Modulation of intestinal microbiota by glycyrrhizic acid prevents high-fat diet-enhanced pre-metastatic niche formation and metastasis.
In Mucosal Immunology on 1 July 2019 by Qiu, M., Huang, K., et al.
PubMed
High-fat diet (HFD) promotes lung pre-metastatic niche formation and metastasis. Thus, there is an urgent need to identify the underlying mechanisms and develop strategies to overcome them. Here we demonstrate that glycyrrhizic acid (GA) prevents HFD-enhanced pre-metastatic niche formation and metastasis through gut microbiota. GA reduced HFD-enhanced myeloid-derived suppressor cell recruitment, pro-metastatic protein S100A8/A9 expression and metastasis burden of 4T1 breast cancer and B16F10 melanoma, accompanied by gut microbiota alteration and colonic macrophage polarization far away the M1-like phenotype. These parameters were greatly decreased by treatment with antibiotics, recolonization of Desulfovibrio vulgaris and Clostridium sordellii, and administration of lipopolysaccharide or deoxycholic acid. Macrophage depletion attenuated HFD-enhanced pre-metastatic niche formation and metastasis, but failed to further affect the effects of GA. Mechanistically, counteraction of HFD-enhanced gut microbiota dysbiosis by GA inhibited Gr-1+ myeloid cell migration and S100A8/A9 expression through decreasing the proportion of M1-like macrophages and their production of CCL2 and TNF-α in the colons via LPS/HMGB1/NF-κB signaling inactivation. Together, targeting the gut microbiota by GA to modulate colonic macrophages could be a novel strategy for the prevention of HFD-enhanced pre-metastatic niche formation and metastasis.
- Genetics
Single-cell RNA-seq reveals spatially restricted multicellular fibrotic niches during lung fibrosis
Preprint on BioRxiv : the Preprint Server for Biology on 6 March 2019 by Joshi, N., Watanabe, S., et al.
PubMed
Ontologically distinct populations of macrophages differentially contribute to organ fibrosis through unknown mechanisms. We applied lineage tracing, spatial methods and single-cell RNA-seq to a spatially-restricted model of asbestos-induced pulmonary fibrosis. We demonstrate that while tissue-resident interstitial macrophages, tissue-resident alveolar macrophages, and monocyte-derived alveolar macrophages are present in the fibrotic niche, only monocyte-derived alveolar macrophages are causally related to fibrosis. Monocyte-derived alveolar macrophages were specifically localized to fibrotic regions in the proximity of fibroblasts where they expressed molecules known to drive fibroblast proliferation, including PDGFA. Moreover, we identified autocrine M-CSF/M-CSFR signaling in monocyte-derived alveolar macrophages as a novel mechanism promoting their self-maintenance and persistence in the fibrotic niche. Pharmacological blockade of M-CSF signaling led to disappearance of the established population of monocyte-derived alveolar macrophages. Thus, our data indicate that monocyte-derived alveolar macrophages are specifically recruited to the fibrotic niche where they are maintained by autocrine signaling and drive fibrosis by stimulating fibroblast proliferation.
- In Vivo,
- Mus musculus (House mouse)
Fetal-derived macrophages dominate in adult mammary glands.
In Nature Communications on 17 January 2019 by Jäppinen, N., Félix, I., et al.
PubMed
Macrophages serve multiple functions including immune regulation, morphogenesis, tissue homeostasis and healing reactions. The current paradigm holds that mammary gland macrophages first arise postnatally during the prepubertal period from the bone marrow-derived monocytes. Here we delineate the origins of tissue-resident mammary gland macrophages using high-dimension phenotypic analyses, cell-fate mapping experiments, gene-deficient mice lacking selective macrophage subtypes, and antibody-based depletion strategies. We show that tissue-resident macrophages are found in mammary glands already before birth, and that the yolk sac-derived and fetal liver-derived macrophages outnumber the adult-derived macrophages in the mammary gland also in the adulthood. In addition, fetal-derived mammary gland macrophages have a characteristic phenotype, display preferential periductal and perivascular localization, and are highly active in scavenging. These findings identify fetal-derived macrophages as the predominant leukocyte type in the adult mammary gland stroma, and reveal previously unknown complexity of macrophage biology in the breast.
- Immunology and Microbiology
Absence of Regulatory T Cells Causes Phenotypic and Functional Switch in Murine Peritoneal Macrophages.
In Frontiers in Immunology on 16 November 2018 by Škuljec, J., Jirmo, A. C., et al.
PubMed
Tissue macrophages are important components of tissue homeostasis and inflammatory pathologies. In the peritoneal cavity, resident macrophages interact with a variety of immune cells and can exhibit broad range of phenotypes and functions. Forkhead-box-P3 (FOXP3)+ regulatory T cells (Tregs) play an indispensable role in maintaining immunological tolerance, yet whether, and how the pathological condition that results from the lack of functional Tregs affects peritoneal macrophages (PM) is largely unknown. We used FOXP3-deficient scurfy (Sf) mice to investigate PM behavior in terms of the missing crosstalk with Tregs. Here, we report that Treg deficiency induced a marked increase in PM numbers, which was reversed after adoptive transfer of CD4+ T cells or neutralization of macrophage colony-stimulating factor. Ex vivo assays demonstrated a pro-inflammatory state of PM from Sf mice and signs of excessive activation and exhaustion. In-depth immunophenotyping of Sf PM using single-cell chipcytometry and transcriptome analysis revealed upregulation of molecules involved in the initiation of innate and adaptive immune responses. Moreover, upon transfer to non-inflammatory environment or after injection of CD4+ T cells, PM from Sf mice reprogramed their functional phenotype, indicating remarkable plasticity. Interestingly, frequencies, and immune polarization of large and small PM subsets were dramatically changed in the FOXP3-deficient mice, suggesting distinct origin and specialized function of these subsets in inflammatory conditions. Our findings demonstrate the significant impact of Tregs in shaping PM identity and dynamics. A better understanding of PM function in the Sf mouse model may have clinical implication for the treatment of immunodysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome, and other forms of immune-mediated enteropathies.
- Cancer Research,
- Immunology and Microbiology
Macrophage-Derived Granulin Drives Resistance to Immune Checkpoint Inhibition in Metastatic Pancreatic Cancer.
In Cancer Research on 1 August 2018 by Quaranta, V., Rainer, C., et al.
PubMed
The ability of disseminated cancer cells to evade the immune response is a critical step for efficient metastatic progression. Protection against an immune attack is often provided by the tumor microenvironment that suppresses and excludes cytotoxic CD8+ T cells. Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive metastatic disease with unmet needs, yet the immunoprotective role of the metastatic tumor microenvironment in pancreatic cancer is not completely understood. In this study, we find that macrophage-derived granulin contributes to cytotoxic CD8+ T-cell exclusion in metastatic livers. Granulin expression by macrophages was induced in response to colony-stimulating factor 1. Genetic depletion of granulin reduced the formation of a fibrotic stroma, thereby allowing T-cell entry at the metastatic site. Although metastatic PDAC tumors are largely resistant to anti-PD-1 therapy, blockade of PD-1 in granulin-depleted tumors restored the antitumor immune defense and dramatically decreased metastatic tumor burden. These findings suggest that targeting granulin may serve as a potential therapeutic strategy to restore CD8+ T-cell infiltration in metastatic PDAC, thereby converting PDAC metastatic tumors, which are refractory to immune checkpoint inhibitors, into tumors that respond to immune checkpoint inhibition therapies.Significance: These findings uncover a mechanism by which metastatic PDAC tumors evade the immune response and provide the rationale for targeting granulin in combination with immune checkpoint inhibitors for the treatment of metastatic PDAC.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/15/4253/F1.large.jpg Cancer Res; 78(15); 4253-69. ©2018 AACR. ©2018 American Association for Cancer Research.
- Immunology and Microbiology
A Macrophage Colony-Stimulating-Factor-Producing γδ T Cell Subset Prevents Malarial Parasitemic Recurrence.
In Immunity on 20 February 2018 by Mamedov, M. R., Scholzen, A., et al.
PubMed
Despite evidence that γδ T cells play an important role during malaria, their precise role remains unclear. During murine malaria induced by Plasmodium chabaudi infection and in human P. falciparum infection, we found that γδ T cells expanded rapidly after resolution of acute parasitemia, in contrast to αβ T cells that expanded at the acute stage and then declined. Single-cell sequencing showed that TRAV15N-1 (Vδ6.3) γδ T cells were clonally expanded in mice and had convergent complementarity-determining region 3 sequences. These γδ T cells expressed specific cytokines, M-CSF, CCL5, CCL3, which are known to act on myeloid cells, indicating that this γδ T cell subset might have distinct functions. Both γδ T cells and M-CSF were necessary for preventing parasitemic recurrence. These findings point to an M-CSF-producing γδ T cell subset that fulfills a specialized protective role in the later stage of malaria infection when αβ T cells have declined. Copyright © 2018. Published by Elsevier Inc.