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Updated: Aug 9, 2026
12:47
Using RNA-interference to Investigate the Innate Immune Response in Mouse Macrophages
Published on: November 3, 2014
Human macrophage-colony stimulating factor: alternative RNA and protein processing from a single gene
D P Cerretti1, J Wignall, D Anderson
1Department of Molecular Biology, Immunex Corporation, Seattle, Washington 98101.
Molecular Immunology
|August 1, 1988
Summary
This study identifies a third human Macrophage-colony stimulating factor (M-CSF) cDNA clone and demonstrates its biological activity. Surprisingly, M-CSF’s membrane-spanning region is not essential for activity but influences cell surface association.
Area of Science:
- Molecular Biology
- Hematopoiesis
- Cell Signaling
Background:
- Macrophage-colony stimulating factor (M-CSF) is crucial for macrophage development.
- Previous research identified two human M-CSF cDNA clones.
- The function of M-CSF variants and their domains requires further investigation.
Purpose of the Study:
- To isolate and characterize a novel human M-CSF cDNA clone.
- To investigate the biological activity and functional domains of M-CSF variants.
- To explore the role of the M-CSF membrane-spanning region in protein activity and localization.
Main Methods:
- Isolation and sequencing of a third human M-CSF cDNA clone and a genomic clone.
- Transfection of COS-7 cells with M-CSF cDNA and genomic clones.
- Assay of biological activity using murine and human bone marrow cell proliferation and colony formation.
- Analysis of M-CSF protein subunits and the effect of the membrane-spanning region.
Main Results:
- A third human M-CSF cDNA encoding a 438 amino acid protein was isolated.
- Transfected cells expressed biologically active M-CSF, stimulating murine and human myeloid cell growth.
- Recombinant human M-CSF did not induce proliferation of human bone marrow cells.
- The membrane-spanning region was not essential for M-CSF activity but mediated cell surface association.
Conclusions:
- Multiple human M-CSF isoforms can be generated from different cDNA clones.
- The M-CSF membrane-spanning region plays a role in protein localization rather than essential biological activity.
- Further research is needed to understand the differential effects of M-CSF on human versus murine cells.
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