Abstract
Cultured human monocytes synthesize factor H (H) and C4 binding protein (C4-bp), as assessed by measuring their presence in culture fluids, and demonstrating the presence of their corresponding mRNAs in total monocyte RNA by Northern blot analysis and by nuclear run-on experiments. H mRNA (4.3 kb and 1.8 kb) could only be detected when cycloheximide (2.5 micrograms/ml) was present in monocyte culture fluid. Recombinant interferon-gamma (IFN-gamma) and lymphoblastoid interferon-alpha (IFN-alpha) produce dose-related increases in the synthesis of H and C4-bp and in the abundance of C4-bp mRNA (2.5 kb). Increased abundance of H mRNA was also seen when cycloheximide (2.5 micrograms/ml) was present in the cultures. Both cytokines increased the transcription rates of the H and C4-bp genes. These changes in transcription were rapid, with significant increases being observed within 30 min of exposure. Following the removal of the cytokines from the cultures the transcription rates of both genes returned to control levels within 4 h. The effects of combining IFN-alpha and IFN-gamma on H and C4-bp transcription rates, mRNA abundances and protein secretion rates were not quantitatively additive. The half-life of H mRNA in monocytes was 15 min, whereas that of C4-bp mRNA was 2 h 45 min. Neither half-life was altered by IFN-gamma.
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
