Radiolabeled Monoclonal Antibody Against Colony-Stimulating Factor 1 Receptor Specifically Distributes to the Spleen and Liver in Immunocompetent Mice

Macrophages can promote tumor development. Preclinically, targeting macrophages by colony-stimulating factor 1 (CSF1)/CSF1 receptor (CSF1R) monoclonal antibodies (mAbs) enhances conventional therapeutics in combination treatments. The physiological distribution and tumor uptake of CSF1R mAbs are unknown. Therefore, we radiolabeled a murine CSF1R mAb and preclinically visualized its biodistribution by PET. CSF1R mAb was conjugated to N-succinyl-desferrioxamine (N-suc-DFO) and subsequently radiolabeled with zirconium-89 (89Zr). Optimal protein antibody dose was first determined in non-tumor-bearing mice to assess physiological distribution. Next, biodistribution of optimal protein dose and 89Zr-labeled isotype control was compared with PET and ex vivo biodistribution after 24 and 72 h in mammary tumor-bearing mice. Tissue autoradiography and immunohistochemistry determined radioactivity distribution and tissue macrophage presence, respectively. [89Zr]Zr-DFO-N-suc-CSF1R-mAb optimal protein dose was 10 mg/kg, with blood pool levels of 10 ± 2% injected dose per gram tissue (ID/g) and spleen and liver uptake of 17 ± 4 and 11 ± 4%ID/g at 72 h. In contrast, 0.4 mg/kg of [89Zr]Zr-DFO-N-suc-CSF1R mAb was eliminated from circulation within 24 h; spleen and liver uptake was 126 ± 44% and 34 ± 7%ID/g, respectively. Tumor-bearing mice showed higher uptake of [89Zr]Zr-DFO-N-suc-CSF1R-mAb in the liver, lymphoid tissues, duodenum, and ileum, but not in the tumor than did 89Zr-labeled control at 72 h. Immunohistochemistry and autoradiography showed that 89Zr was localized to macrophages within lymphoid tissues. Following [89Zr]Zr-DFO-N-suc-CSF1R-mAb administration, tumor macrophages were almost absent, whereas isotype-group tumors contained over 500 cells/mm2. We hypothesize that intratumoral macrophage depletion by [89Zr]Zr-DFO-N-suc-CSF1R-mAb precluded tumor uptake higher than 89Zr-labeled control. Translation of molecular imaging of macrophage-targeting therapeutics to humans may support macrophage-directed therapeutic development.

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Faculty Opinions recommendation of Reduced tissue macrophage population in the lung by anticancer agent cyclophosphamide: restoration by local granulocyte macrophage-colony-stimulating factor gene transfer.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1004017.45005 ◽

2002 ◽

Author(s):

Glenn Dranoff

Keyword(s):

Gene Transfer ◽

Anticancer Agent ◽

Colony Stimulating Factor ◽

Macrophage Population ◽

Factor Gene ◽

Tissue Macrophage ◽

Macrophage Colony Stimulating Factor ◽

Macrophage Colony ◽

Stimulating Factor

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Genome-Wide Association Study Identifies Novel Colony Stimulating Factor 1 Locus Conferring Susceptibility to Cryptococcosis in Human Immunodeficiency Virus-Infected South Africans

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa489 ◽

2020 ◽

Vol 7 (11) ◽

Author(s):

Shichina Kannambath ◽

Joseph N Jarvis ◽

Rachel M Wake ◽

Nicky Longley ◽

Angela Loyse ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Association Study ◽

Cryptococcal Meningitis ◽

Genome Wide Association Study ◽

Ex Vivo ◽

Genome Wide Association ◽

Colony Stimulating Factor ◽

Genome Wide ◽

Immunodeficiency Virus ◽

Stimulating Factor

Abstract Background Cryptococcus is the most common cause of meningitis in human immunodeficiency virus (HIV)-infected Africans. Despite universal exposure, only 5%–10% of patients with HIV/acquired immune deficiency syndrome and profound CD4+ T-cell depletion develop disseminated cryptococcosis: host genetic factors may play a role. Prior targeted immunogenetic studies in cryptococcosis have comprised few Africans. Methods We analyzed genome-wide single-nucleotide polymorphism (SNP) genotype data from 524 patients of African descent: 243 cases (advanced HIV with cryptococcal antigenemia and/or cryptococcal meningitis) and 281 controls (advanced HIV, no history of cryptococcosis, negative serum cryptococcal antigen). Results Six loci upstream of the colony-stimulating factor 1 (CSF1) gene, encoding macrophage colony-stimulating factor (M-CSF) were associated with susceptibility to cryptococcosis at P < 10–6 and remained significantly associated in a second South African cohort (83 cases; 128 controls). Meta-analysis of the genotyped CSF1 SNP rs1999713 showed an odds ratio for cryptococcosis susceptibility of 0.53 (95% confidence interval, 0.42–0.66; P = 5.96 × 10−8). Ex vivo functional validation and transcriptomic studies confirmed the importance of macrophage activation by M-CSF in host defence against Cryptococcus in HIV-infected patients and healthy, ethnically matched controls. Conclusions This first genome-wide association study of susceptibility to cryptococcosis has identified novel and immunologically relevant susceptibility loci, which may help define novel strategies for prevention or immunotherapy of HIV-associated cryptococcal meningitis.

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Preconceptual immune endometrial activation analysis and granulocyte-colony stimulating factor related pathways tested on an ex-vivo model

Fertility and Sterility ◽

10.1016/j.fertnstert.2013.07.759 ◽

2013 ◽

Vol 100 (3) ◽

pp. S376

Author(s):

M. Rahmati ◽

M. Petitbarat ◽

S. Dubanchet ◽

A. Bensussan ◽

G. Chaouat ◽

...

Keyword(s):

Activation Analysis ◽

Ex Vivo ◽

Granulocyte Colony Stimulating Factor ◽

Colony Stimulating Factor ◽

Ex Vivo Model ◽

Stimulating Factor

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Granulocyte-Macrophage Colony-Stimulating Factor Upregulates Reduced 5-Lipoxygenase Metabolism in Peripheral Blood Monocytes and Neutrophils in Acquired Immunodeficiency Syndrome

Blood ◽

10.1182/blood.v94.11.3897 ◽

1999 ◽

Vol 94 (11) ◽

pp. 3897-3905 ◽

Cited By ~ 33

Author(s):

Michael J. Coffey ◽

Susan M. Phare ◽

Sandro Cinti ◽

Marc Peters-Golden ◽

Powel H. Kazanjian

Keyword(s):

Acquired Immunodeficiency Syndrome ◽

Peripheral Blood ◽

Ex Vivo ◽

Colony Stimulating Factor ◽

Gm Csf ◽

Acquired Immunodeficiency ◽

Macrophage Colony Stimulating Factor ◽

Macrophage Colony ◽

Immunodeficiency Syndrome ◽

Stimulating Factor

Abstract Leukotrienes (LT) are mediators derived from the 5-lipoxygenase (5-LO) pathway, which play a role in host defense, and are synthesized by both monocytes (peripheral blood monocyte [PBM]) and neutrophils (PMN). Because 5-LO metabolism is reduced in alveolar macrophages and PMN from acquired immunodeficiency syndrome (AIDS) subjects, we investigated the synthesis of LT by PBM and PMN from these subjects. There was a reduction (74.2% ± 8.8% of control) in LT synthesis in PBM from human immunodeficiency virus (HIV)-infected compared with normal subjects. Expression of 5-LO (51.2% ± 8.8% of control), and 5-LO activating protein (FLAP) (48.5% ± 8.0% of control) was reduced in parallel. We hypothesized that this reduction in LT synthetic capacity in PBM and PMN was due to reduced cytokine production by CD4 T cells, such as granulocyte-macrophage colony-stimulating factor (GM-CSF). We treated 10 AIDS subjects with GM-CSF for 5 days. PBM 5-LO metabolism ex vivo was selectively increased after GM-CSF therapy and was associated with increased 5-LO and FLAP expression. PMN leukotriene B4(LTB4) synthesis was also augmented and associated with increased 5-LO, FLAP, and cytosolic phospholipase A2 expression. In conclusion, as previously demonstrated for PMN, PBM from AIDS subjects also demonstrate reduced 5-LO metabolism. GM-CSF therapy reversed this defect in both PBM and PMN. In view of the role of LT in antimicrobial function, cytokine administration in AIDS may play a role as adjunct therapy for infections.

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Stromal fibroblast heparan sulfate is required for cytokine-mediated ex vivo maintenance of human long-term culture-initiating cells

Blood ◽

10.1182/blood.v87.8.3229.bloodjournal8783229 ◽

1996 ◽

Vol 87 (8) ◽

pp. 3229-3236 ◽

Cited By ~ 97

Author(s):

P Gupta ◽

JB McCarthy ◽

CM Verfaillie

Keyword(s):

Stem Cell ◽

Heparan Sulfate ◽

Ex Vivo ◽

Function Analysis ◽

Soluble Form ◽

Stromal Fibroblast ◽

Colony Stimulating Factor ◽

Long Term Culture ◽

Stimulating Factor

We have recently demonstrated that 50% of primitive human long-term culture-initiating cells (LTC-IC) are maintained for up to 8 weeks in stroma-dependent cultures in which progenitor-stroma contact is prevented (stroma noncontact), or when progenitors are cultured in medium conditioned by stromal feeders. This indicates that factors responsible for LTC-IC maintenance are present in soluble form in stromal supernatant (SN). Although the picogram concentrations of cytokines present in stromal SN can induce the differentiation of CD34+/HLA-DR- (DR-) cells to clonogenic cells (colony forming cells; CFC), they maintain only 10% of LTC-IC for 5 weeks, suggesting that factors other than these cytokines are required for LTC-IC maintenance. To characterize the factor(s) in stromal SN responsible for LTC-IC maintenance, we purified glycoproteins and proteoglycans (PG) from the SN of the LTC-IC supportive murine marrow stromal fibroblast cell line M2–10B4 by ion exchange high performance liquid chromatography (HPLC). Culture of DR- cells in a combination of M2–10B4-derived PG, but not glycoproteins and picogram concentrations of recombinant human interleukin-6 (IL-6), granulocyte colony-stimulating factor (G-CSF), stem cell factor (SCF), leukemia inhibitory factor (LIF), granulocyte- macrophage colony-stimulating factor (GM-CSF), and macrophage inflammatory protein-1alpha (MIP-1alpha) resulted in the recovery of 96% +/- 8% of LTC-IC maintained in cultures supplemented with unfractionated stromal SN. LTC-IC maintenance was largely retained after digestion of the PG-rich fraction with proteinase K and after dissociative gel filtration chromatography, but was completely abolished following treatment with nitrous acid, which digests heparan sulfate glycosaminoglycans (HS GAG). As for M2–10B4-derived HS GAG, high concentrations of bovine kidney HS GAG, but not bovine tracheal chondroitin sulfate, significantly improved cytokine-mediated LTC-IC maintenance. Maintenance of LTC-IC by these nonmarrow-derived HS GAG was, however, significantly lower than that seen with M2–10B4-derived HS. These studies demonstrate a role for marrow stroma-derived HS GAG in the long-term in vitro maintenance of human LTC-IC. Further structure-function analysis of these HS GAG may have important implications for ex vivo stem cell expansion and gene transfer into hematopoietic progenitors.

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