Serum soluble CD8 molecule is a marker of CD8 T-cell activation in HIV-1 disease.
To characterize CD8 T-cell activation during HIV-1 infection we measured serum soluble CD8 (sCD8) levels longitudinally in seroconverters and in individuals with established HIV infection who were in different stages of illness. CD8 T-cell activation occurs very early in HIV infection. Serum sCD8 levels were elevated in 91.5% of the first seropositive samples in seroconverters. Furthermore, CD8 T-cell activation persists throughout HIV infection. sCD8 predicted the occurrence of AIDS in HIV-seropositive individuals and so the addition of serum sCD8 levels to CD4 T-cell measurements increased the power in predicting the onset of AIDS. The serum level of sCD8 was particularly relevant to the prediction of subsequent CD4 T-cell fall relatively early in infection, for example, in the 3 years after seroconversion. However, later in HIV infection, for example within 2 years prior to development of AIDS, sCD8 levels were less predictive. sCD8 correlated with levels of beta 2-microglobulin and neopterin, which reflect activation of cell types other than CD8. Thus, serum sCD8 level can be a useful marker of specific CD8 T-cell activation, and is an independent predictor of prognosis in HIV infection.
Nishanian
P
P
Center for Interdisciplinary Research in Immunology and Disease (CIRID), UCLA School of Medicine.
Hofmann
B
B
Wang
Y
Y
Jackson
A L
AL
Detels
R
R
Fahey
J L
JL
D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology / Q000503:physiopathology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D016827:CD8 Antigens; D015331:Cohort Studies; D015658:HIV Infections / Q000276:immunology*; D006679:HIV Seropositivity / Q000276:immunology; D015497:HIV-1; D008213:Lymphocyte Activation; D016131:Lymphocyte Subsets / Q000276:immunology*; D012995:Solubility
D000945:Antigens, Differentiation, T-Lymphocyte; D015415:Biomarkers; D016827:CD8 Antigens