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) dise ase, a question central to the pathogenesis of HIV is whether or not t he depletion of CD4(+) lymphocytes is a random or selective event, The majority of peripheral blood T lymphocytes use alpha and beta variabl e chains as components of their T-cell receptor (TCR) complex, Depleti on of CD4(+) T lymphocytes from the peripheral blood may be dependent on the V beta chain expressed by the CD4(+) cell, based on the hypothe sis that HIV may encode a superantigen. Peripheral blood from normal c ontrols and HIV+ patients was studied for alterations in the expressio n 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 be ta 13, and V beta 19 on all lymphocytes and on both CD4(+) and CD8(+) lymphocytes independently, Alteration of the V beta chains in HIV+ dis ease was analyzed as a function of absolute CD4 count and Centers for Disease Control (CDC) stage of the patient. These data suggest that th e loss of T helper (CD4) lymphocytes during the course of HIV disease may be a selective event, These data are consistent with the hypothesi s that selective depletion of CD4(+), V beta 19(+) lymphocytes may be due to the encoding of a superantigen by HIV. Furthermore, using multi color flow cytometry and stratifying patients by absolute CD4 counts ( or stage of disease) may reveal immunologic changes that might otherwi se he overlooked. (C) 1995 Wiley-Liss, Inc.