The influence of fetal calf serum on interferon-gamma induced HLA-DR expression on U937 cells.
The induction of HLA-DR antigen expression on U937 cells by interferon-gamma (IFN-gamma) is positively influenced by amount of fetal calf serum (FCS) added to the tissue culture medium. A transient alkalinization of FCS before its addition to the medium, dramatically decreased the immunomodulating activity of IFN-gamma. FCS was also found to be a dose-dependent enhancer of the IFN-gamma-induced 2',5'-oligoadenylate (2-5A) synthetase production. Our findings suggest the need for a serum factor(s), labile at basic pH values, to support at least two of the multiple IFN-gamma activities.
Institute of Microbiology, University of Brescia, Italy.
J
J
Gao
S
S
Folghera
S
S
Fiorentini
M
M
Tinti
C
C
Varinacci
G
G
Flamminio
L
L
Peroni
A
A
Caruso
D015088:2',5'-Oligoadenylate Synthetase / Q000096:biosynthesis; D000818:Animals; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D005312:Fetal Blood / Q000502:physiology*; D006684:HLA-DR Antigens / Q000032:analysis*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007371:Interferon-gamma / Q000494:pharmacology*; D009000:Monocytes / Q000276:immunology
D006684:HLA-DR Antigens; D007371:Interferon-gamma; D015088:2',5'-Oligoadenylate Synthetase