Cell Surface Phenotypic Changes Induced in H9 T Cells Chronically Infected with HTLV Type I or HIV Type 1 or Coinfected with the Two Viruses

Abstract

To investigate whether HTLV-I infection, HIV-I infection, or HIV-I infection of HTLV-I-infected cells affect the expression of cellular surface molecules, an HTLV-I-infected T cell line derived from the H9 T cell line was established (H36). H9 cells uninfected or infected with HTLV-I were then infected with HIV-1. We have compared the density of different 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 complex (MHC) antigens (class I and II), and adhesion molecules (LFA-1 and ICAM-1). The experiments reported in this article show that chronic HTLV-I infection, HIV-1 infection, and HIV-1 infection of HTLV-I-infected T cells modulate the expression of several immunologically important cell surface antigens. The nature and the extent of T lymphoid cell phenotypic modulation depend on the infecting virus. Furthermore, HTLV-I and HIV-1 interact with each other in the phenotypic modulation of coinfected cells.

Physical and Functional Interaction between the Human T-Cell Lymphotropic Virus Type 1 Tax1 Protein and the CCAAT Binding Protein NF-Y

“…(3,25,38,47,51,64). Therefore, we sought to determine what effect the interaction of Tax with NF-Y has on the expression of MHC class II genes.…”

“…Quantitative and qualitative changes in the expression of MHC class II molecules on the cell surface dramatically affect the onset of the immune response and may be the basis of a wide variety of disease states (51). By cell surface staining, the MHC class II molecule has been shown to be elevated in peripheral blood lymphocytes isolated from HTLV-1-infected patients as compared to normal donors (3,47,64,92). In addition, HTLV-1 infection of neuroblastoma cells or transfection of a glial cell line with Tax demonstrated that Tax activated the expression of MHC class II in these cells (47).…”

Complement-dependent cytotoxic antibodies to human T lymphotropic virus type I (HTLV-I)-infected cells in the sera of HTLV-I-infected individuals

“…H36 expresses HTLV-I antigens on the cell membrane surface [25]. Although the percentage of HTLV-I cells in H36 cultures fluctuated with time between 30% and 80% as indicated by immunofluorescence analysis [25], the use of this line and H9 cells (as well as H9-III B , H9-MN) allowed simultaneous testing of the effects of sera on target cells differing from one another by virtue only of their infection status. Such uninfected control cells are not available for any of the other cell lines chronically infected with HTLV-I.…”

“…These cell lines all express viral antigens [23] with the exception of line C8166 which contains a defective HTLV-I provirus. H9 cells [24] were persistently infected with HTLV-I (H36) [25], with HIV IIIB (H9-III B ) or HIV MN (H9-MN) (obtained from the AIDS Research and Reference Reagent Program, National Institute of Health, Bethesda, MD). These lines were used to detect complement-dependent cytotoxic antibodies to HTLV-I and HIV-1.…”

Simian Retrovirus Infections: Potential Confounding Variables in Primate Toxicology Studies

“…Altered cell surface markers, including increased expression of CD25, and down regulation of CD71, HLA class II antigens and certain adhesion molecules (LFA1) have been observed in HTLV infection (46). Similar studies of cell surface changes induced by STLV infection in nonhuman primates are lacking.…”