ALTERATIONS OF T-CELL RECEPTOR VARIABLE REGION EXPRESSION IN HUMAN-IMMUNODEFICIENCY-VIRUS DISEASE

Since only a small percentage of CD4(+) lymphocytes is infected at any one time during the course of human immunodeficiency virus (HIV) disease, a question central to the pathogenesis of HIV is whether or not the depletion of CD4(+) lymphocytes is a random or selective event, The majority of peripheral blood T lymphocytes use alpha and beta variable chains as components of their T-cell receptor (TCR) complex, Depletion of CD4(+) T lymphocytes from the peripheral blood may be dependent on the V beta chain expressed by the CD4(+) cell, based on the hypothesis that HIV may encode a superantigen. Peripheral blood from normal controls and HIV+ patients was studied for alterations in the expression of various V beta chains of the TCR. Three-color flaw cytometry was used to determine the expression of V beta 2, V beta 3, V beta 8, V beta 13, and V beta 19 on all lymphocytes and on both CD4(+) and CD8(+) lymphocytes independently, Alteration of the V beta chains in HIV+ disease was analyzed as a function of absolute CD4 count and Centers for Disease Control (CDC) stage of the patient. These data suggest that the loss of T helper (CD4) lymphocytes during the course of HIV disease may be a selective event, These data are consistent with the hypothesis that selective depletion of CD4(+), V beta 19(+) lymphocytes may be due to the encoding of a superantigen by HIV. Furthermore, using multicolor flow cytometry and stratifying patients by absolute CD4 counts (or stage of disease) may reveal immunologic changes that might otherwise he overlooked. (C) 1995 Wiley-Liss, Inc.