Immune response in experimentally induced uremia. VI. Uremic macrophages are defective in their ability to present antigen to T cells.
The ability of uremic lymphocytes to respond to antigens was examined. We have found that (1) The ability of uremic unfractionated lymph node cells to respond to antigens is severely diminished when compared to the response of control cells; (2) Uremic macrophages are defective in their ability to present antigen to T cells; (3) Treatment of control splenic macrophages with monoclonal anti-Ia antibodies diminishes these macrophages' ability to present antigen, while uremic macrophages so treated show little change in their already diminished accessory cell function; and (4) The uremic splenic macrophage population has more small cells and less Ia determinants per cell than do control splenic macrophages as determined by cytofluorographic analysis. The percentage of Ia+ splenic macrophages is similar in control and uremic rats. It appears that the diminished response of uremic cells to antigens is due to the inability of uremic macrophages to present antigen to T cells. This may play a role in the increased rate of infections seen in uremic patients.
D000818:Animals; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D008198:Lymph Nodes / Q000166:cytology; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology*; D014511:Uremia / Q000276:immunology*
D000949:Histocompatibility Antigens Class II