Gamma interferon induces the appearance of a CD4-, major histocompatibility complex class II+ macrophage subpopulation in the rat peritoneal cavity.
Peritoneal cells from gamma interferon (IFN-gamma)-treated rats were phenotypically characterized by flow cytometry. Intraperitoneal inoculation of 3 x 10(4) units of IFN-gamma induced, within 24 h, the appearance of a CD4-, major histocompatibility complex (MHC) class II+ macrophage subpopulation not present in rats treated with phosphate-buffered saline. IFN-gamma induced an increased expression of MHC class II I-A molecules on both CD4- and CD4+ macrophages. Both cell types adhered to plastic and expressed high levels of the macrophage membrane molecules CD11b and OX41. Histological examination of sorted CD4- and CD4+ macrophages confirmed the macrophage morphology of both populations with less granula in the former. We conclude that the appearance of CD4- macrophages in the peritoneal cavity after inoculation with IFN-gamma most probably reflects a selective recruitment of these cells from blood or surrounding tissues. The function of these cells is still unknown, although strong expression of MHC class II I-A indicates competence as antigen-presenting cells.
Ericsson
P O
PO
Wallenberg Laboratory, University of Lund, Sweden.
Hedlund
G
G
Dohlsten
M
M
Carlsson
R
R
Sjögren
H O
HO
D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis*; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000032:analysis*; D007371:Interferon-gamma / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D010529:Peritoneal Cavity / Q000166:cytology; D051381:Rats
D000945:Antigens, Differentiation, T-Lymphocyte; D000949:Histocompatibility Antigens Class II; D007371:Interferon-gamma