CELL-SURFACE PHENOTYPIC CHANGES INDUCED IN H9 T-CELLS CHRONICALLY INFECTED WITH HTLV TYPE-I OR HIV TYPE-1 OR COINFECTED WITH THE 2 VIRUSES

To investigate whether HTLV-I infection, HIV-1 infection, or HIV-1 inf ection of HTLV-I-infected cells affect the expression of cellular surf ace molecules, an HTLV-I-infected T cell line derived from the H9 T ce ll line was established (H36). H9 cells uninfected or infected with HT LV-I were then infected with HIV-1. We have compared the density of di fferent surface markers on these three infected H9 T cell lines. These markers consist of T cell-specific antigens (CD2, CD3, CD4, and CD8), activated T cell antigens (CD25 and CD71), major histocompatibility c omplex (MHC) antigens (class I and II), and adhesion molecules (LFA-1 and ICAM-1). The experiments reported in this article show that chroni c HTLV-I infection, HIV-1 infection, and HIV-1 infection of HTLV-I-inf ected T cells modulate the expression of several immunologically impor tant cell surface antigens. The nature and the extent of T lymphoid ce ll phenotypic modulation depend on the infecting virus. Furthermore, H TLV-I and HIV-1 interact with each other in the phenotypic modulation of coinfected cells.