$178.00 - $4,651.50

$178.00 - $4.00

Choose an Option...
  • 100 mg - $4,651.50
  • 50 mg - $3,286.00
  • 25 mg - $2,183.00
  • 5 mg - $652.00
  • 1 mg - $178.00
  • Custom Amount (Quotes Only)
In stock
Only %1 left

Product Description

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 ≤1EU/mg (≤0.001EU/μg)
Determined by LAL 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.
Need a Custom Formulation? See All Antibody Customization Options

Application References

  • 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.

    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
    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.

    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
    Conde, P., et al (2015). "DC-SIGN(+) Macrophages Control the Induction of Transplantation Tolerance" Immunity 42(6): 1143-1158.

    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
    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.

    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.

Product Citations

  • NEK8 kinase-mediated lactate increase impairs antitumor immunity decreasing radiotherapy sensitivity in colorectal cancer.

    In Nat Commun on 28 March 2026 by Li, M., Ni, Y., et al.

    PubMed

    Radiotherapy effectively treats colorectal cancer (CRC), but local recurrence remains common and abscopal effects-regression of tumors distant from irradiated sites-are rarely observed even with immune checkpoint inhibitors. Here we show that the protein kinase NEK8, highly expressed in CRC, promotes radioresistance by suppressing anti-tumor immunity. In radiation-resistant tumors, NEK8 phosphorylates lactate dehydrogenase A (LDHA), driving lactate overproduction. This metabolite promotes histone modifications that silence antigen presentation machinery, while extracellular lactate directly impairs CD8+ T cell function, collectively excluding CD8+ T cell from the tumor microenvironment. Pharmacological inhibition of NEK8 using CX6258 restores CD8+ T cell infiltration and enhances both local and systemic tumor control following radiotherapy. These findings establish NEK8 as a promising therapeutic target for overcoming radioresistance and inducing abscopal responses in CRC.

  • Identification of endometrial CD169+ macrophages essential for Treg cell accumulation and implantation.

    In Cell Rep on 24 March 2026 by Ohki, T., Miyawaki, S., et al.

    PubMed

    Successful pregnancy requires coordinated regulation between the innate and adaptive immune systems. Regulatory T (Treg) cells are essential for establishing maternal immune tolerance to the semi-allogeneic fetus, but the innate immune cells that modulate this process remain poorly defined. Here, we identify CD169+ macrophages in the endometrium as critical regulators of Treg cell recruitment and implantation. These CD169+ macrophages are endometrial localized, exhibit an anti-inflammatory phenotype, and secrete chemokines that attract Treg cells to the endometrium. We also identified CD169+ macrophages in the human endometrium that express chemokines involved in Treg cell recruitment. Our findings identify endometrial CD169+ macrophages as key orchestrators of Treg cell accumulation at the maternal-fetal interface, providing mechanistic insight into implantation and conceptus development.

  • Fibroblast STAT3 Activation Drives Organ-Specific Premetastatic Niche Formation.

    In Cancer Res on 2 January 2026 by Lasse Opsahl, E. L., Espinoza, C. E., et al.

    PubMed

    Pancreatic cancer is associated with a high rate of metastasis and poor prognosis. The formation of a premetastatic niche (PMN) facilitates cancer cell spread and contributes to cancer mortality. Using murine pancreatic cancer models based on expression of oncogenic KRAS in the pancreas epithelium, we discovered that remodeling of the lung microenvironment occurred in mice bearing pancreatic precursor lesions prior to cancer formation. This early-lesion PMN resembled the PMN in cancer-bearing mice, and both feature characteristics of overt metastasis, such as transcriptional reprogramming, activation of fibroblast STAT3 signaling, and infiltration of immunosuppressive arginase 1-positive macrophages. Both patients with pancreatic cancer and mouse models demonstrated elevated serum IL6. Inactivating oncogenic KRAS reduced serum IL6 and reverted fibroblast STAT3 phosphorylation in mouse lungs; loss of lung fibroblast STAT3 phosphorylation was similarly observed when mice were treated with the pan-RAS inhibitor RMC-7977. Whereas arginase 1-positive macrophage infiltration was dispensable for fibroblast STAT3 activation, IL6 blockade inhibited lung fibroblast STAT3 activation. Functionally, fibroblast STAT3 activation was necessary for lung metastasis establishment and growth. Interestingly, activation of STAT3 in the PMN was present in the lungs but not in the liver, in which fibroblast reprogramming occurred only in overt metastasis, pointing to organ-specific PMN formation. In human metastasis samples, phosphorylated STAT3 in fibroblasts was similarly more abundant in the lungs than liver. Together, these data point to organ-specific mechanisms driving formation of the PMN and indicate that reprogramming of the microenvironment prior to metastasis might support early dissemination of pancreatic cancer.

  • Myelopoiesis is temporally dynamic and is regulated by lifestyle to modify multiple sclerosis.

    In Nat Commun on 17 April 2025 by Yates, A. G., Khamhoung, A., et al.

    PubMed

    Monocytes and neutrophils from the myeloid lineage contribute to multiple sclerosis (MS), but the dynamics of myelopoiesis during MS are unclear. Here we uncover a disease stage-specific relationship between lifestyle, myelopoiesis and neuroinflammation. In mice with relapsing-remitting experimental autoimmune encephalomyelitis (RR-EAE), myelopoiesis in the femur, vertebrae and spleen is elevated prior to disease onset and during remission, preceding the peaks of clinical disability and neuroinflammation. In progressive EAE (P-EAE), vertebral myelopoiesis rises steadily throughout disease, while femur and splenic myelopoiesis is elevated early before waning later during disease height. In parallel, sleep disruption or hyperlipidemia and cardiometabolic syndrome augment M-CSF generation and multi-organ myelopoiesis to worsen P-EAE clinical symptoms, neuroinflammation, and spinal cord demyelination, with M-CSF blockade abrogating these symptoms. Lastly, results from a previous trial show that Mediterranean diet restrains myelopoietic activity and myeloid lineage progenitor skewing and improves clinical symptomology of MS. Together, our data suggest that myelopoiesis in MS is dynamic and dependent on disease stage and location, and that lifestyle factors modulate disease by influencing M-CSF-mediated myelopoiesis.

Product FAQs