Peripheral blood mononuclear cells from AIDS patients release but do not respond to antigen-stimulated NK-activating lymphokines.
We have previously shown that streptococcal product (SP) extracted from the culture supernatants of Streptococcus pyogenes ATCC 19615 augments NK activity, partly by inducing the release of soluble factors from mononuclear cells. In this study we use SP as an NK stimulant to investigate the mechanism of NK depression in AIDS. We demonstrate that the NK activity of AIDS patients is lower than normal controls and can be significantly enhanced with SP, although not to control levels. The decreased cytotoxicity in AIDS is not due to a depletion of NK cells, nor to the depletion of lymphokines from CD4 cells that are directly involved in NK cell activation. PBMCs from patients with AIDS respond to SP, producing normal levels of NK-enhancing substances in their supernatants. However, upon examining the ability of SP-induced supernatants from control cells to augment the NK activity of cells from AIDS patients, we find significantly less activity in AIDS cells than in control cells, suggesting an intrinsic effector dysfunction of NK cells in AIDS.
Lapham
C K
CK
Department of Microbiology and Immunology, SUNY Health Science Center at Syracuse.
Sacks
L V
LV
Tomar
R H
RH
D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000328:Adult; D000942:Antigens, Bacterial / Q000008:administration & dosage; D000943:Antigens, Differentiation; D000945:Antigens, Differentiation, T-Lymphocyte; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008222:Lymphokines / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011961:Receptors, Fc; D017452:Receptors, IgG; D013297:Streptococcus pyogenes / Q000276:immunology
D000942:Antigens, Bacterial; D000943:Antigens, Differentiation; D000945:Antigens, Differentiation, T-Lymphocyte; D008222:Lymphokines; D011961:Receptors, Fc; D017452:Receptors, IgG