InVivoMAb anti-mouse CSF1R (CD115)
Product Details
The AFS98 monoclonal antibody reacts with mouse colony stimulating factor 1 receptor (CSF1R), also known as macrophage colony-stimulating factor receptor (M-CSFR), and CD115. CSF1R is a single-pass type I membrane protein and member of the platelet-derived growth factor receptor family. In mice CSF1R is expressed by monocytes/macrophages, peritoneal exudate cells, plasmacytoid and conventional dendritic cells, and osteoclasts. CSF1R is a receptor for CSF1 and CSF1 signaling through CSF1R regulates the proliferation and differentiation of cells in the monocytic lineage. The AFS98 antibody has been reported to deplete macrophages and block CSFR1 in vivo.Specifications
Isotype | Rat IgG2a,Ā Īŗ |
---|---|
Recommended Isotype Control(s) | InVivoMAb rat IgG2a isotype control, anti-trinitrophenol |
Recommended Dilution Buffer | InVivoPure pH 7.0 Dilution Buffer |
Conjugation | This product is unconjugated. Conjugation is available via our Antibody Conjugation Services. |
Immunogen | Not available or unknown |
Reported Applications |
in vivo macrophage depletion in vitro CSF1R neutralization in vivo monocyte depletion Flow cytometry Western blot |
Formulation |
PBS, pH 7.0 Contains no stabilizers or preservatives |
Endotoxin |
<2EU/mg (<0.002EU/μg) Determined by LAL gel clotting assay |
Purity |
>95% Determined by SDS-PAGE |
Sterility | 0.2 µm filtration |
Production | Purified from cell culture supernatant in an animal-free facility |
Purification | Protein G |
RRID | AB_2687699 |
Molecular Weight | 150 kDa |
Storage | The antibody solution should be stored at the stock concentration at 4°C. Do not freeze. |
Additional Formats
Recommended Products
in vivo macrophage depletion
Bauche, D., et al. (2018). "LAG3(+) Regulatory T Cells Restrain Interleukin-23-Producing CX3CR1(+) Gut-Resident Macrophages during Group 3 Innate Lymphoid Cell-Driven Colitis" Immunity 49(2): 342-352 e345. PubMed
Interleukin-22 (IL-22)-producing group 3 innate lymphoid cells (ILC3) maintains gut homeostasis but can also promote inflammatory bowel disease (IBD). The regulation of ILC3-dependent colitis remains to be elucidated. Here we show that Foxp3(+) regulatory T cells (Treg cells) prevented ILC3-mediated colitis in an IL-10-independent manner. Treg cells inhibited IL-23 and IL-1beta production from intestinal-resident CX3CR1(+) macrophages but not CD103(+) dendritic cells. Moreover, Treg cells restrained ILC3 production of IL-22 through suppression of CX3CR1(+) macrophage production of IL-23 and IL-1beta. This suppression was contact dependent and was mediated by latent activation gene-3 (LAG-3)-an immune checkpoint receptor-expressed on Treg cells. Engagement of LAG-3 on MHC class II drove profound immunosuppression of CX3CR1(+) tissue-resident macrophages. Our study reveals that the health of the intestinal mucosa is maintained by an axis driven by Treg cells communication with resident macrophages that withhold inflammatory stimuli required for ILC3 function.
in vivo macrophage depletion
Gordon, S. R., et al. (2017). "PD-1 expression by tumour-associated macrophages inhibits phagocytosis and tumour immunity" Nature 545(7655): 495-499. PubMed
Programmed cell death protein 1 (PD-1) is an immune checkpoint receptor that is upregulated on activated T cells for the induction of immune tolerance. Tumour cells frequently overexpress the ligand for PD-1, programmed cell death ligand 1 (PD-L1), facilitating their escape from the immune system. Monoclonal antibodies that block the interaction between PD-1 and PD-L1, by binding to either the ligand or receptor, have shown notable clinical efficacy in patients with a variety of cancers, including melanoma, colorectal cancer, non-small-cell lung cancer and Hodgkinās lymphoma. Although it is well established that PD-1-PD-L1 blockade activates T cells, little is known about the role that this pathway may have in tumour-associated macrophages (TAMs). Here we show that both mouse and human TAMs express PD-1. TAM PD-1 expression increases over time in mouse models of cancer and with increasing disease stage in primary human cancers. TAM PD-1 expression correlates negatively with phagocytic potency against tumour cells, and blockade of PD-1-PD-L1 in vivo increases macrophage phagocytosis, reduces tumour growth and lengthens the survival of mice in mouse models of cancer in a macrophage-dependent fashion. This suggests that PD-1-PD-L1 therapies may also function through a direct effect on macrophages, with substantial implications for the treatment of cancer with these agents.
in vivo macrophage depletion
Moynihan, K. D., et al. (2016). "Eradication of large established tumors in mice by combination immunotherapy that engages innate and adaptive immune responses" Nat Med. doi : 10.1038/nm.4200. PubMed
Checkpoint blockade with antibodies specific for cytotoxic T lymphocyte-associated protein (CTLA)-4 or programmed cell death 1 (PDCD1; also known as PD-1) elicits durable tumor regression in metastatic cancer, but these dramatic responses are confined to a minority of patients. This suboptimal outcome is probably due in part to the complex network of immunosuppressive pathways present in advanced tumors, which are unlikely to be overcome by intervention at a single signaling checkpoint. Here we describe a combination immunotherapy that recruits a variety of innate and adaptive immune cells to eliminate large tumor burdens in syngeneic tumor models and a genetically engineered mouse model of melanoma; to our knowledge tumors of this size have not previously been curable by treatments relying on endogenous immunity. Maximal antitumor efficacy required four components: a tumor-antigen-targeting antibody, a recombinant interleukin-2 with an extended half-life, anti-PD-1 and a powerful T cell vaccine. Depletion experiments revealed that CD8+ T cells, cross-presenting dendritic cells and several other innate immune cell subsets were required for tumor regression. Effective treatment induced infiltration of immune cells and production of inflammatory cytokines in the tumor, enhanced antibody-mediated tumor antigen uptake and promoted antigen spreading. These results demonstrate the capacity of an elicited endogenous immune response to destroy large, established tumors and elucidate essential characteristics of combination immunotherapies that are capable of curing a majority of tumors in experimental settings typically viewed as intractable.
in vivo macrophage depletion
Arnold, I. C., et al. (2015). "CD11c monocyte/macrophages promote chronic Helicobacter hepaticus-induced intestinal inflammation through the production of IL-23" Mucosal Immunol. doi : 10.1038/mi.2015.65. PubMed
In inflammatory bowel diseases, a breakdown in host microbial interactions accompanies sustained activation of immune cells in the gut. Functional studies suggest a key role for interleukin-23 (IL-23) in orchestrating intestinal inflammation. IL-23 can be produced by various mononuclear phagocytes (MNPs) following acute microbial stimulation, but little is known about the key cellular sources of IL-23 that drive chronic intestinal inflammation. Here we have addressed this question using a physiological model of bacteria-driven colitis. By combining conditional gene ablation and gene expression profiling, we found that IL-23 production by CD11c+ MNPs was essential to trigger intestinal immunopathology and identified MHCII+ monocytes and macrophages as the major source of IL-23. Expression of IL-23 by monocytes was acquired during their differentiation in the intestine and correlated with the expression of major histocompatibility complex class II (MHCII) and CD64. In contrast, Batf3-dependent CD103+ CD11b- dendritic cells were dispensable for bacteria-induced colitis in this model. These studies reinforce the pathogenic role of monocytes in dysregulated responses to intestinal bacteria and identify production of IL-23 as a key component of this response. Further understanding of the functional sources of IL-23 in diverse forms of intestinal inflammation may lead to novel therapeutic strategies aimed at interrupting IL-23-driven immune pathology.Mucosal Immunology advance online publication 5 August 2015. doi:10.1038/mi.2015.65.
in vivo monocyte depletion
Naik, S., et al. (2015). "Commensal-dendritic-cell interaction specifies a unique protective skin immune signature" Nature 520(7545): 104-108. PubMed
The skin represents the primary interface between the host and the environment. This organ is also home to trillions of microorganisms that play an important role in tissue homeostasis and local immunity. Skin microbial communities are highly diverse and can be remodelled over time or in response to environmental challenges. How, in the context of this complexity, individual commensal microorganisms may differentially modulate skin immunity and the consequences of these responses for tissue physiology remains unclear. Here we show that defined commensals dominantly affect skin immunity and identify the cellular mediators involved in this specification. In particular, colonization with Staphylococcus epidermidis induces IL-17A(+) CD8(+) T cells that home to the epidermis, enhance innate barrier immunity and limit pathogen invasion. Commensal-specific T-cell responses result from the coordinated action of skin-resident dendritic cell subsets and are not associated with inflammation, revealing that tissue-resident cells are poised to sense and respond to alterations in microbial communities. This interaction may represent an evolutionary means by which the skin immune system uses fluctuating commensal signals to calibrate barrier immunity and provide heterologous protection against invasive pathogens. These findings reveal that the skin immune landscape is a highly dynamic environment that can be rapidly and specifically remodelled by encounters with defined commensals, findings that have profound implications for our understanding of tissue-specific immunity and pathologies.
in vivo macrophage depletion
Kaminsky, L. W., et al. (2015). "Redundant Function of Plasmacytoid and Conventional Dendritic Cells Is Required To Survive a Natural Virus Infection" J Virol 89(19): 9974-9985. PubMed
Viruses that spread systemically from a peripheral site of infection cause morbidity and mortality in the human population. Innate myeloid cells, including monocytes, macrophages, monocyte-derived dendritic cells (mo-DC), and dendritic cells (DC), respond early during viral infection to control viral replication, reducing virus spread from the peripheral site. Ectromelia virus (ECTV), an orthopoxvirus that naturally infects the mouse, spreads systemically from the peripheral site of infection and results in death of susceptible mice. While phagocytic cells have a requisite role in the response to ECTV, the requirement for individual myeloid cell populations during acute immune responses to peripheral viral infection is unclear. In this study, a variety of myeloid-specific depletion methods were used to dissect the roles of individual myeloid cell subsets in the survival of ECTV infection. We showed that DC are the primary producers of type I interferons (T1-IFN), requisite cytokines for survival, following ECTV infection. DC, but not macrophages, monocytes, or granulocytes, were required for control of the virus and survival of mice following ECTV infection. Depletion of either plasmacytoid DC (pDC) alone or the lymphoid-resident DC subset (CD8alpha(+) DC) alone did not confer lethal susceptibility to ECTV. However, the function of at least one of the pDC or CD8alpha(+) DC subsets is required for survival of ECTV infection, as mice depleted of both populations were susceptible to ECTV challenge. The presence of at least one of these DC subsets is sufficient for cytokine production that reduces ECTV replication and virus spread, facilitating survival following infection. IMPORTANCE: Prior to the eradication of variola virus, the orthopoxvirus that causes smallpox, one-third of infected people succumbed to the disease. Following successful eradication of smallpox, vaccination rates with the smallpox vaccine have significantly dropped. There is now an increasing incidence of zoonotic orthopoxvirus infections for which there are no effective treatments. Moreover, the safety of the smallpox vaccine is of great concern, as complications may arise, resulting in morbidity. Like many viruses that cause significant human diseases, orthopoxviruses spread from a peripheral site of infection to become systemic. This study elucidates the early requirement for innate immune cells in controlling a peripheral infection with ECTV, the causative agent of mousepox. We report that there is redundancy in the function of two innate immune cell subsets in controlling virus spread early during infection. The viral control mediated by these cell subsets presents a potential target for therapies and rational vaccine design.
in vitro CSF-R1 neutralization
Sheng, K. C., et al. (2014). "IL-3 and CSF-1 interact to promote generation of CD11c+ IL-10-producing macrophages" PLoS One 9(4): e95208. PubMed
Unraveling the mechanisms of hematopoiesis regulated by multiple cytokines remains a challenge in hematology. IL-3 is an allergic cytokine with the multilineage potential, while CSF-1 is produced in the steady state with restricted lineage coverage. Here, we uncovered an instructive role of CSF-1 in IL-3-mediated hematopoiesis. CSF-1 significantly promoted IL-3-driven CD11c+ cell expansion and dampened basophil and mast cell generation from C57BL/6 bone marrow. Further studies indicated that the CSF-1/CSF-1R axis contributed significantly to IL-3-induced CD11c+ cell generation through enhancing c-Fos-associated monopoiesis. CD11c+ cells induced by IL-3 or IL-3/CSF-1 were competent in cellular maturation and endocytosis. Both IL-3 and IL-3/CSF-1 cells lacked classical dendritic cell appearance and resembled macrophages in morphology. Both populations produced a high level of IL-10, in addition to IL-1, IL-6 and TNFalpha, in response to LPS, and were relatively poor T cell stimulators. Collectively, these findings reveal a role for CSF-1 in mediating the IL-3 hematopoietic pathway through monopoiesis, which regulates expansion of CD11c+ macrophages.
in vivo monocyte depletion
Greter, M., et al. (2012). "GM-CSF controls nonlymphoid tissue dendritic cell homeostasis but is dispensable for the differentiation of inflammatory dendritic cells" Immunity 36(6): 1031-1046. PubMed
GM-CSF (Csf-2) is a critical cytokine for the in vitro generation of dendritic cells (DCs) and is thought to control the development of inflammatory DCs and resident CD103(+) DCs in some tissues. Here we showed that in contrast to the current understanding, Csf-2 receptor acts in the steady state to promote the survival and homeostasis of nonlymphoid tissue-resident CD103(+) and CD11b(+) DCs. Absence of Csf-2 receptor on lung DCs abrogated the induction of CD8(+) T cell immunity after immunization with particulate antigens. In contrast, Csf-2 receptor was dispensable for the differentiation and innate function of inflammatory DCs during acute injuries. Instead, inflammatory DCs required Csf-1 receptor for their development. Thus, Csf-2 is important in vaccine-induced CD8(+) T cell immunity through the regulation of nonlymphoid tissue DC homeostasis rather than control of inflammatory DCs in vivo.
Flow Cytometry
Li, W., et al. (2012). "Intravital 2-photon imaging of leukocyte trafficking in beating heart" J Clin Invest 122(7): 2499-2508. PubMed
Two-photon intravital microscopy has substantially broadened our understanding of tissue- and organ-specific differences in the regulation of inflammatory responses. However, little is known about the dynamic regulation of leukocyte recruitment into inflamed heart tissue, largely due to technical difficulties inherent in imaging moving tissue. Here, we report a method for imaging beating murine hearts using intravital 2-photon microscopy. Using this method, we visualized neutrophil trafficking at baseline and during inflammation. Ischemia reperfusion injury induced by transplantation or transient coronary artery ligation led to recruitment of neutrophils to the heart, their extravasation from coronary veins, and infiltration of the myocardium where they formed large clusters. Grafting hearts containing mutant ICAM-1, a ligand important for neutrophil recruitment, reduced the crawling velocities of neutrophils within vessels, and markedly inhibited their extravasation. Similar impairment was seen with the inhibition of Mac-1, a receptor for ICAM-1. Blockade of LFA-1, another ICAM-1 receptor, prevented neutrophil adherence to endothelium and extravasation in heart grafts. As inflammatory responses in the heart are of great relevance to public health, this imaging approach holds promise for studying cardiac-specific mechanisms of leukocyte recruitment and identifying novel therapeutic targets for treating heart disease.
Flow Cytometry
Tagliani, E., et al. (2011). "Coordinate regulation of tissue macrophage and dendritic cell population dynamics by CSF-1" J Exp Med 208(9): 1901-1916. PubMed
Tissue macrophages (Mphis) and dendritic cells (DCs) play essential roles in tissue homeostasis and immunity. How these cells are maintained at their characteristic densities in different tissues has remained unclear. Aided by a novel flow cytometric technique for assessing relative rates of blood-borne precursor recruitment, we examined Mphi and DC population dynamics in the pregnant mouse uterus, where rapid tissue growth facilitated a dissection of underlying regulatory mechanisms. We demonstrate how Mphi dynamics, and thus Mphi tissue densities, are locally controlled by CSF-1, a pleiotropic growth factor whose in situ level of activity varied widely between uterine tissue layers. CSF-1 acted in part by inducing Mphi proliferation and in part by stimulating the extravasation of Ly6C(hi) monocytes (Mos) that served as Mphi precursors. Mo recruitment was dependent on the production of CCR2 chemokine receptor ligands by uterine Mphis in response to CSF-1. Unexpectedly, a parallel CSF-1-regulated, but CCR2-independent pathway influenced uterine DC tissue densities by controlling local pre-DC extravasation rates. Together, these data provide cellular and molecular insight into the regulation of Mphi tissue densities under noninflammatory conditions and reveal a central role for CSF-1 in the coordination of Mphi and DC homeostasis.
Lim, A. K., et al. (2009). "Antibody blockade of c-fms suppresses the progression of inflammation and injury in early diabetic nephropathy in obese db/db mice" Diabetologia 52(8): 1669-1679. PubMed
AIMS/HYPOTHESIS: Macrophage-mediated renal injury plays an important role in the development of diabetic nephropathy. Colony-stimulating factor (CSF)-1 is a cytokine that is produced in diabetic kidneys and promotes macrophage accumulation, activation and survival. CSF-1 acts exclusively through the c-fms receptor, which is only expressed on cells of the monocyte-macrophage lineage. Therefore, we used c-fms blockade as a strategy to selectively target macrophage-mediated injury during the progression of diabetic nephropathy. METHODS: Obese, type 2 diabetic db/db BL/KS mice with established albuminuria were treated with a neutralising anti-c-fms monoclonal antibody (AFS98) or isotype matched control IgG from 12 to 18 weeks of age and examined for renal injury. RESULTS: Treatment with AFS98 did not affect obesity, hyperglycaemia, circulating monocyte levels or established albuminuria in db/db mice. However, AFS98 did prevent glomerular hyperfiltration and suppressed variables of inflammation in the diabetic kidney, including kidney macrophages (accumulation, activation and proliferation), chemokine CC motif ligand 2 levels (mRNA and urine protein), kidney activation of proinflammatory pathways (c-Jun amino-terminal kinase and activating transcription factor 2) and Tnf-alpha (also known as Tnf) mRNA levels. In addition, AFS98 decreased the tissue damage caused by macrophages including tubular injury (apoptosis and hypertrophy), interstitial damage (cell proliferation and myofibroblast accrual) and renal fibrosis (Tgf-beta1 [also known as Tgfb1] and Col4a1 mRNA). CONCLUSIONS/INTERPRETATION: Blockade of c-fms can suppress the progression of established diabetic nephropathy in db/db mice by targeting macrophage-mediated injury.


- Mus musculus (House mouse),
- Biochemistry and Molecular biology,
- Cell Biology,
- Genetics
Histone methyltransferase ASH1L primes metastases and metabolic reprogramming of macrophages in the bone niche.
In Nature Communications on 20 May 2025 by Meng, C., Lin, K., et al.
Bone metastasis is a major cause of cancer death; however, the epigenetic determinants driving this process remain elusive. Here, we report that histone methyltransferase ASH1L is genetically amplified and is required for bone metastasis in men with prostate cancer. ASH1L rewires histone methylations and cooperates with HIF-1α to induce pro-metastatic transcriptome in invading cancer cells, resulting in monocyte differentiation into lipid-associated macrophage (LA-TAM) and enhancing their pro-tumoral phenotype in the metastatic bone niche. We identified IGF-2 as a direct target of ASH1L/HIF-1α and mediates LA-TAMs' differentiation and phenotypic changes by reprogramming oxidative phosphorylation. Pharmacologic inhibition of the ASH1L-HIF-1α-macrophages axis elicits robust anti-metastasis responses in preclinical models. Our study demonstrates epigenetic alterations in cancer cells reprogram metabolism and features of myeloid components, facilitating metastatic outgrowth. It establishes ASH1L as an epigenetic driver priming metastasis and macrophage plasticity in the bone niche, providing a bona fide therapeutic target in metastatic malignancies. © 2025. The Author(s).
- Cancer Research
Ultra-high dose rate radiotherapy overcomes radioresistance in head and neck squamous cell carcinoma.
In Signal Transduction and Targeted Therapy on 3 March 2025 by Li, H. S., Tang, R., et al.
Radiotherapy (RT) resistance in head and neck squamous cell carcinoma (HNSCC) significantly hampers local control and patient prognosis. This study investigated the efficacy and molecular mechanisms of high-energy X-ray-based ultra-high dose rate radiotherapy (UHDR-RT) in overcoming RT resistance. The established RT-resistant HNSCC cell lines and animal models were subjected to UHDR-RT or conventional RT (Conv-RT) via a high-power rhodotron accelerator. Cellular assays assessed the malignant phenotype, viability, and degree of DNA damage, whereas in vivo evaluations focused on tumor proliferation and the tumor immune microenvironment (TiME). Transcriptome sequencing and Olink proteomics were employed to explore the underlying mechanisms involved. In vitro experiments indicated that UHDR-RT suppressed radioresistant cell proliferation and invasion, while promoting apoptosis and exacerbating DNA damage. In contrast, its efficacy in radiosensitive cells was comparable to that of Conv-RT. In vivo studies using patient-derived xenograft nude mice models demonstrated that UHDR-RT only partially reversed RT resistance. Transcriptomic and proteomic analyses of C57BL/6J mice models revealed the predominant role of TiME modulating in reversing radioresistance. Immunofluorescence and flow cytometry confirmed increased CD8+ T cells and an increased M1/M2 macrophage ratio post-UHDR-RT. Mechanistically, UHDR-RT activated CD8+ T cells, which stimulated M1 macrophages through paracrine IFN-γ signaling, thereby enhancing TiME activation. Furthermore, the activated M1 macrophages secreted CXCL9, which in turn reactivated CD8+ T cells, forming a feedforward loop that amplified TiME activation. This study elucidates the dual role of UHDR-RT in directly inducing DNA damage and modulating the TiME, highlighting its potential in treating radioresistant HNSCC. © 2025. The Author(s).
- Biochemistry and Molecular biology,
- Cell Biology
CD226+adipose tissue macrophages arise from MDP-derived monocytes and regulate lipid metabolism
Preprint on BioRxiv : the Preprint Server for Biology on 5 December 2024 by Gallerand, A., Caillot, Z., et al.
Macrophages are innate immune cells present in all tissues, in which they participate in immune responses and maintenance of tissue homeostasis. They develop either from embryonic precursors or from circulating monocytes, and their functions are in part dictated by their origin. We previously observed robust monocyte recruitment and contribution to the macrophage pool in brown adipose tissue. In particular, monocytes were predicted to give rise to two phenotypically distinct macrophage subsets identifiable by CD206 or CD226 expression. In the present study, we investigated monocyte differentiation pathways in brown adipose tissue and the function of monocyte-derived macrophages. We found that bone marrow monocytes highly contributed to the CD226 + macrophage population while the CD206 + population contained mainly yolk sac-derived cells. Fate mapping analysis revealed a low contribution of GMP- and a high contribution of MDP-derived monocytes to the CD226 + macrophage subset. Importantly, adoptive transfer experiments demonstrate that MDP- but not GMP-derived monocytes are pre-conditioned to give rise to CD226 + macrophages. Using meta-analysis of single cell RNA-sequencing data, we found that MDP-derived CD226 + macrophages were present in several tissues including peritoneal cavity, adrenal glands and all adipose depots, with a particular enrichment in beige and brown fat. A similar macrophage subset was identified in humans. Functionally, while depletion of CD206 + macrophages using anti-CD115 blocking antibodies led to decreased adipose triglyceride content, genetic depletion of CD226 + macrophages caused the opposite phenotype. We thus identify CD226 + MDP-derived macrophages as a new myeloid cell type conserved across tissues and tied to lipid metabolism homeostasis.
- Biochemistry and Molecular biology,
- Cell Biology,
- Endocrinology and Physiology
Endothelial metabolic control of insulin sensitivity through resident macrophages.
In Cell Metabolism on 5 November 2024 by Zhang, J., SjĆøberg, K. A., et al.
Endothelial cells (ECs) not only form passive blood conduits but actively contribute to nutrient transport and organ homeostasis. The role of ECs in glucose homeostasis is, however, poorly understood. Here, we show that, in skeletal muscle, endothelial glucose transporter 1 (Glut1/Slc2a1) controls glucose uptake via vascular metabolic control of muscle-resident macrophages without affecting transendothelial glucose transport. Lowering endothelial Glut1 via genetic depletion (Glut1ĪEC) or upon a short-term high-fat diet increased angiocrine osteopontin (OPN/Spp1) secretion. This promoted resident muscle macrophage activation and proliferation, which impaired muscle insulin sensitivity. Consequently, co-deleting Spp1 from ECs prevented macrophage accumulation and improved insulin sensitivity in Glut1ĪEC mice. Mechanistically, Glut1-dependent endothelial glucose metabolic rewiring increased OPN in a serine metabolism-dependent fashion. Our data illustrate how the glycolytic endothelium creates a microenvironment that controls resident muscle macrophage phenotype and function and directly links resident muscle macrophages to the maintenance of muscle glucose homeostasis. Copyright Ā© 2024 The Author(s). Published by Elsevier Inc. All rights reserved.
- Immunology and Microbiology,
- Stem Cells and Developmental Biology
Dermal TRPV1 innervations engage a macrophage- and fibroblast-containing pathway to activate hair growth in mice.
In Developmental Cell on 4 November 2024 by Ben-Shaanan, T. L., Knƶpper, K., et al.
Pain, detected by nociceptors, is an integral part of injury, yet whether and how it can impact tissue physiology and recovery remain understudied. Here, we applied chemogenetics in mice to locally activate dermal TRPV1 innervations in naive skin and found that it triggered new regenerative cycling by dormant hair follicles (HFs). This was preceded by rapid apoptosis of dermal macrophages, mediated by the neuropeptide calcitonin gene-related peptide (CGRP). TRPV1 activation also triggered a macrophage-dependent induction of osteopontin (Spp1)-expressing dermal fibroblasts. The neuropeptide CGRP and the extracellular matrix protein Spp1 were required for the nociceptor-triggered hair growth. Finally, we showed that epidermal abrasion injury induced Spp1-expressing dermal fibroblasts and hair growth via a TRPV1 neuron and CGRP-dependent mechanism. Collectively, these data demonstrated a role for TRPV1 nociceptors in orchestrating a macrophage and fibroblast-supported mechanism to promote hair growth and enabling the efficient restoration of this mechano- and thermo-protective barrier after wounding. Copyright Ā© 2024 The Authors. Published by Elsevier Inc. All rights reserved.
- Immunology and Microbiology
Thymosin α1 reverses oncolytic adenovirus-induced M2 polarization of macrophages to improve antitumor immunity and therapeutic efficacy.
In Cell Reports Medicine on 15 October 2024 by Liu, K., Kong, L., et al.
Although oncolytic adenoviruses are widely studied for their direct oncolytic activity and immunomodulatory role in cancer immunotherapy, the immunosuppressive feedback loop induced by oncolytic adenoviruses remains to be studied. Here, we demonstrate that type V adenovirus (ADV) induces the polarization of tumor-associated macrophages (TAMs) to the M2 phenotype and increases the infiltration of regulatory T cells (Tregs) in the tumor microenvironment (TME). By selectively compensating for these deficiencies, thymosin alpha 1 (Tα1) reprograms "M2-like" TAMs toward an antitumoral phenotype, thereby reprogramming the TME into a state more beneficial for antitumor immunity. Moreover, ADVTα1 is constructed by harnessing the merits of all the components for the aforementioned combinatorial therapy. Both exogenously supplied and adenovirus-produced Tα1 orchestrate TAM reprogramming and enhance the antitumor efficacy of ADV via CD8+ T cells, showing promising prospects for clinical translation. Our findings provide inspiration for improving oncolytic adenovirus combination therapy and designing oncolytic engineered adenoviruses. Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.
Reduction of circulating IgE and allergens by a pH-sensitive antibody with enhanced FcγRIIb binding.
In Molecular Therapy on 2 October 2024 by Li, N., Gong, N., et al.
Allergen-crosslinked IgE triggers allergy by interacting with its receptor on basophils and mast cells. The anti-IgE monoclonal antibody omalizumab can alleviate allergy by competing with the receptor for IgE binding. However, along with neutralization, omalizumab also inhibits IgE degradation, which is clinically associated with high-dose and total IgE accumulation problems. In this study, we have developed an IgE-eliminating antibody on the basis of omalizumab, which has pH-dependent Fabs and an Fc with high affinity for FcγRIIb. In mice, the antibody rapidly eliminated total serum IgE to baseline levels and caused lower free IgE levels than omalizumab. At low dosages, the antibody also exhibited favorable IgE elimination effects. In addition, the antibody can degrade the corresponding allergen with the removal of IgE, addressing the allergy from its source. Introduction of the M252Y/S254T/T256E (YTE) mutation into this antibody prolongs its serum half-life without reducing potency. Thus, this engineered antibody holds a promising therapeutic option for allergy patients. Mechanistic insights are also included in this study. Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.
- Mus musculus (House mouse),
- Neuroscience
FcγR- and CD9-dependent synapse engulfing microglia in the thalamus drives cognitive impairment following cortical brain injury
Preprint on BioRxiv : the Preprint Server for Biology on 23 September 2024 by Matoba, K., Kochi, T., et al.
Various states of microglia appear in neuroinflammation, but their impact on brain function and behavior is not fully understood. Here we report that synapse engulfing microglia in the thalamus are crucial for cognitive impairment after cortical brain injury. Region-specific manipulations of reactive microglia in the chronic phase of injuries showed that microglial changes in the thalamus, but not in the hippocampus, impaired recognition memory. Single-cell RNA-sequencing analysis revealed the enrichment of synapse engulfing microglia in the thalamus, which developed in a CD9-dependent manner and caused synaptic loss and recognition memory deficits. In the thalamus, the blood-brain barrier was disrupted, and extravasated γ-immunoglobulins (IgG) co-localized with synapse engulfing microglia. Fcγ receptor III blockade in the thalamus reduced synapse engulfing microglia, synapse loss, and recognition memory deficits. These findings demonstrate that the induction of synapse engulfing microglia in the thalamus by extravasated IgG/FcγRIII and CD9 signals causes recognition memory deficits after cortical brain injury.
- Mus musculus (House mouse),
- Immunology and Microbiology
West Nile virus triggers intestinal dysmotility via T cell-mediated enteric nervous system injury.
In The Journal of Clinical Investigation on 29 August 2024 by Janova, H., Zhao, F. R., et al.
Intestinal dysmotility syndromes have been epidemiologically associated with several antecedent bacterial and viral infections. To model this phenotype, we previously infected mice with the neurotropic flavivirus West Nile virus (WNV) and demonstrated intestinal transit defects. Here, we found that within 1 week of WNV infection, enteric neurons and glia became damaged, resulting in sustained reductions of neuronal cells and their networks of connecting fibers. Using cell-depleting antibodies, adoptive transfer experiments, and mice lacking specific immune cells or immune functions, we show that infiltrating WNV-specific CD4+ and CD8+ T cells damaged the enteric nervous system (ENS) and glia, which led to intestinal dysmotility; these T cells used multiple and redundant effector molecules including perforin and Fas ligand. In comparison, WNV-triggered ENS injury and intestinal dysmotility appeared to not require infiltrating monocytes, and damage may have been limited by resident muscularis macrophages. Overall, our experiments support a model in which antigen-specific T cell subsets and their effector molecules responding to WNV infection direct immune pathology against enteric neurons and supporting glia that results in intestinal dysmotility.
- Mus musculus (House mouse),
- Immunology and Microbiology
Adipose tissue macrophage infiltration and hepatocyte stress increase GDF-15 throughout development of obesity to MASH.
In Nature Communications on 21 August 2024 by L'homme, L., Sermikli, B. P., et al.
Plasma growth differentiation factor-15 (GDF-15) levels increase with obesity and metabolic dysfunction-associated steatotic liver disease (MASLD) but the underlying mechanism remains poorly defined. Using male mouse models of obesity and MASLD, and biopsies from carefully-characterized patients regarding obesity, type 2 diabetes (T2D) and MASLD status, we identify adipose tissue (AT) as the key source of GDF-15 at onset of obesity and T2D, followed by liver during the progression towards metabolic dysfunction-associated steatohepatitis (MASH). Obesity and T2D increase GDF15 expression in AT through the accumulation of macrophages, which are the main immune cells expressing GDF15. Inactivation of Gdf15 in macrophages reduces plasma GDF-15 concentrations and exacerbates obesity in mice. During MASH development, Gdf15 expression additionally increases in hepatocytes through stress-induced TFEB and DDIT3 signaling. Together, these results demonstrate a dual contribution of AT and liver to GDF-15 production in metabolic diseases and identify potential therapeutic targets to raise endogenous GDF-15 levels. Ā© 2024. The Author(s).
- Mus musculus (House mouse)
Comprehensive assembly of monoclonal and mixed antibody sequences
Preprint on BioRxiv : the Preprint Server for Biology on 10 August 2024 by Jiang, W., Xiong, Y., et al.
The elucidation of antibody sequence information is crucial for understanding antigen binding and advancing therapeutic and research applications. However, complete de novo assembly of monoclonal antibody sequences remains challenging due to accuracy and robustness limitations. To address this issue, we introduce Fusion, an innovative de novo assembler that integrates overlapping peptides and template information into complete sequences using a beam search strategy. We demonstrate Fusionās performance by reconstructing multiple human and murine antibodies with highest accuracy (100% and over 99%, respectively). Biological validation of the recombinantly expressed AFS98 antibody with unknown sequences further supports its effectiveness. Furthermore, current methods are applicable only to traditional monoclonal antibody sequencing assembly, presenting a significant bottleneck in achieving higher throughput. In contrast, Fusion can assemble peptide sequences from mixtures of two or three monoclonal antibodies into complete individual sequences with the same accuracy as traditional sequencing, significantly enhancing throughput. To our knowledge, this is the first study enabling high-throughput sequencing of multiple antibodies using only bottom-up mass spectrometry. The duration, expense, and reagent consumption of mass spectrometry detection are comparable to those required for sequencing a single monoclonal antibody. In summary, Fusionās superior performance in handling the complex antibody sequencing represents a significant advancement in antibody research.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
Reprogramming the tumor immune microenvironment using engineered dual-drug loaded Salmonella.
In Nature Communications on 6 August 2024 by Nguyen, D. H., You, S. H., et al.
Synergistic combinations of immunotherapeutic agents can improve the performance of anti-cancer therapies but may lead to immune-mediated adverse effects. These side-effects can be overcome by using a tumor-specific delivery system. Here, we report a method of targeted immunotherapy using an attenuated Salmonella typhimurium (SAM-FC) engineered to release dual payloads: cytolysin A (ClyA), a cytolytic anti-cancer agent, and Vibrio vulnificus flagellin B (FlaB), a potent inducer of anti-tumor innate immunity. Localized secretion of ClyA from SAM-FC induces immunogenic cancer cell death and promotes release of tumor-specific antigens and damage-associated molecular patterns, which establish long-term antitumor memory. Localized secretion of FlaB promotes phenotypic and functional remodeling of intratumoral macrophages that markedly inhibits tumor metastasis in mice bearing tumors of mouse and human origin. Both primary and metastatic tumors from bacteria-treated female mice are characterized by massive infiltration of anti-tumorigenic innate immune cells and activated tumor-specific effector/memory T cells; however, the percentage of immunosuppressive cells is low. Here, we show that SAM-FC induces functional reprogramming of the tumor immune microenvironment by activating both the innate and adaptive arms of the immune system and can be used for targeted delivery of multiple immunotherapeutic payloads for the establishment of potent and long-lasting antitumor immunity. Ā© 2024. The Author(s).
- Mus musculus (House mouse),
- Cardiovascular biology
Macrophages preserve endothelial cell specialization in the adrenal gland to modulate aldosterone secretion and blood pressure.
In Cell Reports on 23 July 2024 by Fan, Z., Karakone, M., et al.
Macrophages play crucial roles in organ-specific functions and homeostasis. In the adrenal gland, macrophages closely associate with sinusoidal capillaries in the aldosterone-producing zona glomerulosa. We demonstrate that macrophages preserve capillary specialization and modulate aldosterone secretion. Using macrophage-specific deletion of VEGF-A, single-cell transcriptomics, and functional phenotyping, we found that the loss of VEGF-A depletes PLVAP+ fenestrated endothelial cells in the zona glomerulosa, leading to increased basement membrane collagen IV deposition and subendothelial fibrosis. This results in increased aldosterone secretion, called "haptosecretagogue" signaling. Human aldosterone-producing adenomas also show capillary rarefaction and basement membrane thickening. Mice with myeloid cell-specific VEGF-A deletion exhibit elevated serum aldosterone, hypokalemia, and hypertension, mimicking primary aldosteronism. These findings underscore macrophage-to-endothelial cell signaling as essential for endothelial cell specialization, adrenal gland function, and blood pressure regulation, with broader implications for other endocrine organs. Copyright Ā© 2024 The Authors. Published by Elsevier Inc. All rights reserved.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
An in-situ peptide-antibody self-assembly to block CD47 and CD24 signaling enhances macrophage-mediated phagocytosis and anti-tumor immune responses.
In Nature Communications on 6 July 2024 by Zhang, W., Zeng, Y., et al.
Targeted immunomodulation for reactivating innate cells, especially macrophages, holds great promise to complement current adaptive immunotherapy. Nevertheless, there is still a lack of high-performance therapeutics for blocking macrophage phagocytosis checkpoint inhibitors in solid tumors. Herein, a peptide-antibody combo-supramolecular in situ assembled CD47 and CD24 bi-target inhibitor (PAC-SABI) is described, which undergoes biomimetic surface propagation on cancer cell membranes through ligand-receptor binding and enzyme-triggered reactions. By simultaneously blocking CD47 and CD24 signaling, PAC-SABI enhances the phagocytic ability of macrophages in vitro and in vivo, promoting anti-tumor responses in breast and pancreatic cancer mouse models. Moreover, building on the foundation of PAC-SABI-induced macrophage repolarization and increased CD8+ T cell tumor infiltration, sequential anti-PD-1 therapy further suppresses 4T1 tumor progression, prolonging survival rate. The in vivo construction of PAC-SABI-based nano-architectonics provides an efficient platform for bridging innate and adaptive immunity to maximize therapeutic potency. Ā© 2024. The Author(s).
- Biochemistry and Molecular biology,
- Cancer Research,
- Cell Biology,
- Immunology and Microbiology
Metabolic Reprogramming of Tumor-Associated Macrophages Using Glutamine Antagonist JHU083 Drives Tumor Immunity in Myeloid-Rich Prostate and Bladder Cancers.
In Cancer Immunology Research on 2 July 2024 by Praharaj, M., Shen, F., et al.
Glutamine metabolism in tumor microenvironments critically regulates antitumor immunity. Using the glutamine-antagonist prodrug JHU083, we report potent tumor growth inhibition in urologic tumors by JHU083-reprogrammed tumor-associated macrophages (TAMs) and tumor-infiltrating monocytes. We show JHU083-mediated glutamine antagonism in tumor microenvironments induced by TNF, proinflammatory, and mTORC1 signaling in intratumoral TAM clusters. JHU083-reprogrammed TAMs also exhibited increased tumor cell phagocytosis and diminished proangiogenic capacities. In vivo inhibition of TAM glutamine consumption resulted in increased glycolysis, a broken tricarboxylic acid (TCA) cycle, and purine metabolism disruption. Although the antitumor effect of glutamine antagonism on tumor-infiltrating T cells was moderate, JHU083 promoted a stem cell-like phenotype in CD8+ T cells and decreased the abundance of regulatory T cells. Finally, JHU083 caused a global shutdown in glutamine-utilizing metabolic pathways in tumor cells, leading to reduced HIF-1α, c-MYC phosphorylation, and induction of tumor cell apoptosis, all key antitumor features. Altogether, our findings demonstrate that targeting glutamine with JHU083 led to suppressed tumor growth as well as reprogramming of immunosuppressive TAMs within prostate and bladder tumors that promoted antitumor immune responses. JHU083 can offer an effective therapeutic benefit for tumor types that are enriched in immunosuppressive TAMs. ©2024 The Authors; Published by the American Association for Cancer Research.
- Cancer Research,
- Immunology and Microbiology
Chemoradiotherapy-induced ACKR2+ tumor cells drive CD8+ TĀ cell senescence and cervical cancer recurrence.
In Cell Reports Medicine on 21 May 2024 by Dai, D., Pei, Y., et al.
Tumor recurrence after chemoradiotherapy is challenging to overcome, and approaches to predict the recurrence remain elusive. Here, human cervical cancer tissues before and after concurrent chemoradiotherapy (CCRT) analyzed by single-cell RNA sequencing reveal that CCRT specifically promotes CD8+ T cell senescence, driven by atypical chemokine receptor 2 (ACKR2)+ CCRT-resistant tumor cells. Mechanistically, ACKR2 expression is increased in response to CCRT and is also upregulated through the ligation of CC chemokines that are produced by activated myeloid and T cells. Subsequently, ACKR2+ tumor cells are induced to produce transforming growth factor β to drive CD8+ T cell senescence, thereby compromising antitumor immunity. Moreover, retrospective analysis reveals that ACKR2 expression and CD8+ T cell senescence are enhanced in patients with cervical cancer who experienced recurrence after CCRT, indicating poor prognosis. Overall, we identify a subpopulation of CCRT-resistant ACKR2+ tumor cells driving CD8+ T cell senescence and tumor recurrence and highlight the prognostic value of ACKR2 and CD8+ T cell senescence for chemoradiotherapy recurrence. Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
Macrophage-fibroblast JAK/STAT dependent crosstalk promotes liver metastatic outgrowth in pancreatic cancer.
In Nature Communications on 27 April 2024 by Raymant, M., Astuti, Y., et al.
Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic disease for which better therapies are urgently needed. Fibroblasts and macrophages are heterogeneous cell populations able to enhance metastasis, but the role of a macrophage-fibroblast crosstalk in regulating their pro-metastatic functions remains poorly understood. Here we deconvolve how macrophages regulate metastasis-associated fibroblast (MAF) heterogeneity in the liver. We identify three functionally distinct MAF populations, among which the generation of pro-metastatic and immunoregulatory myofibroblastic-MAFs (myMAFs) critically depends on macrophages. Mechanistically, myMAFs are induced through a STAT3-dependent mechanism driven by macrophage-derived progranulin and cancer cell-secreted leukaemia inhibitory factor (LIF). In a reciprocal manner, myMAF secreted osteopontin promotes an immunosuppressive macrophage phenotype resulting in the inhibition of cytotoxic T cell functions. Pharmacological blockade of STAT3 or myMAF-specific genetic depletion of STAT3 restores an anti-tumour immune response and reduces metastases. Our findings provide molecular insights into the complex macrophage-fibroblast interactions in tumours and reveal potential targets to inhibit PDAC liver metastasis. Ā© 2024. The Author(s).
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
Heterodimerization of T cell engaging bispecific antibodies to enhance specificity against pancreatic ductal adenocarcinoma.
In Journal of Hematology & Oncology on 23 April 2024 by Long, A. W., Xu, H., et al.
EGFR and/or HER2 expression in pancreatic cancers is correlated with poor prognoses. We generated homodimeric (EGFRxEGFR or HER2xHER2) and heterodimeric (EGFRxHER2) T cell-engaging bispecific antibodies (T-BsAbs) to direct polyclonal T cells to these antigens on pancreatic tumors. EGFR and HER2 T-BsAbs were constructed using the 2ā+ā2 IgG-[L]-scFv T-BsAbs format bearing two anti-CD3 scFvs attached to the light chains of an IgG to engage T cells while retaining bivalent binding to tumor antigens with both Fab arms. A Fab arm exchange strategy was used to generate EGFRxHER2 heterodimeric T-BsAb carrying one Fab specific for EGFR and one for HER2. EGFR and HER2 T-BsAbs were also heterodimerized with a CD33 control T-BsAb to generate 'tumor-monovalent' EGFRxCD33 and HER2xCD33 T-BsAbs. T-BsAb avidity for tumor cells was studied by flow cytometry, cytotoxicity by T-cell mediated 51Chromium release, and in vivo efficacy against cell line-derived xenografts (CDX) or patient-derived xenografts (PDX). Tumor infiltration by T cells transduced with luciferase reporter was quantified by bioluminescence. The EGFRxEGFR, HER2xHER2, and EGFRxHER2 T-BsAbs demonstrated high avidity and T cell-mediated cytotoxicity against human pancreatic ductal adenocarcinoma (PDAC) cell lines in vitro with EC50s in the picomolar range (0.17pM to 18pM). They were highly efficient in driving human polyclonal T cells into subcutaneous PDAC xenografts and mediated potent T cell-mediated anti-tumor effects. Both EGFRxCD33 and HER2xCD33 tumor-monovalent T-BsAbs displayed substantially reduced avidity by SPR when compared to homodimeric EGFRxEGFR or HER2xHER2 T-BsAbs (ā¼150-fold and ā¼6000-fold respectively), tumor binding by FACS (8.0-fold and 63.6-fold), and T-cell mediated cytotoxicity (7.7-fold and 47.2-fold), while showing no efficacy against CDX or PDX. However, if either EGFR or HER2 was removed from SW1990 by CRISPR-mediated knockout, the in vivo efficacy of heterodimeric EGFRxHER2 T-BsAb was lost. EGFR and HER2 were useful targets for driving T cell infiltration and tumor ablation. Two arm Fab binding to either one or both targets was critical for robust anti-tumor effect in vivo. By engaging both targets, EGFRxHER2 heterodimeric T-BsAb exhibited potent anti-tumor effects if CDX or PDX were EGFR+HER2+ double-positive with the potential to spare single-positive normal tissue. Ā© 2024. The Author(s).
- Mus musculus (House mouse),
- Cancer Research
CCR2 and CCR5 co-inhibition modulates immunosuppressive myeloid milieu in glioma and synergizes with anti-PD-1 therapy.
In Oncoimmunology on 9 April 2024 by Pant, A., Hwa-Lin Bergsneider, B., et al.
PubMed
Immunotherapy has revolutionized the treatment of cancers. Reinvigorating lymphocytes with checkpoint blockade has become a cornerstone of immunotherapy for multiple tumor types, but the treatment of glioblastoma has not yet shown clinical efficacy. A major hurdle to treat GBM with checkpoint blockade is the high degree of myeloid-mediated immunosuppression in brain tumors that limits CD8 T-cell activity. A potential strategy to improve anti-tumor efficacy against glioma is to use myeloid-modulating agents to target immunosuppressive cells, such as myeloid-derived suppressor cells (MDSCs) in the tumor microenvironment. We found that the co-inhibition of the chemokine receptors CCR2 and CCR5 in murine model of glioma improves the survival and synergizes robustly with anti-PD-1 therapy. Moreover, the treatment specifically reduced the infiltration of monocytic-MDSCs (M-MDSCs) into brain tumors and increased lymphocyte abundance and cytokine secretion by tumor-infiltrating CD8 T cells. The depletion of T-cell subsets and myeloid cells abrogated the effects of CCR2 and CCR5 blockade, indicating that while broad depletion of myeloid cells does not improve survival, specific reduction in the infiltration of immunosuppressive myeloid cells, such as M-MDSCs, can boost the anti-tumor immune response of lymphocytes. Our study highlights the potential of CCR2/CCR5 co-inhibition in reducing myeloid-mediated immunosuppression in GBM patients. Ā© 2024 The Author(s). Published with license by Taylor & Francis Group, LLC.
- Mus musculus (House mouse),
- Cancer Research,
- Immunology and Microbiology
A multiomics analysis-assisted deep learning model identifies a macrophage-oriented module as a potential therapeutic target in colorectal cancer.
In Cell Reports Medicine on 20 February 2024 by Bao, X., Li, Q., et al.
Colorectal cancer (CRC) is a common malignancy involving multiple cellular components. The CRC tumor microenvironment (TME) has been characterized well at single-cell resolution. However, a spatial interaction map of the CRC TME is still elusive. Here, we integrate multiomics analyses and establish a spatial interaction map to improve the prognosis, prediction, and therapeutic development for CRC. We construct a CRC immune module (CCIM) that comprises FOLR2+ macrophages, exhausted CD8+ TĀ cells, tolerant CD8+ TĀ cells, exhausted CD4+ TĀ cells, and regulatory TĀ cells. Multiplex immunohistochemistry is performed to depict the CCIM. Based on this, we utilize advanced deep learning technology to establish a spatial interaction map and predict chemotherapy response. CCIM-Net is constructed, which demonstrates good predictive performance for chemotherapy response in both the training and testing cohorts. Lastly, targeting FOLR2+ macrophage therapeutics is used to disrupt the immunosuppressive CCIM and enhance the chemotherapy response inĀ vivo. Copyright Ā© 2024 The Author(s). Published by Elsevier Inc. All rights reserved.