2003 Volume 24 Issue 2 Pages 59-69
For determining the actual antigenic molecules in human immunodeficiency virus type-l (HIV-l) recognized by cytotoxic T lymphocytes (CTLs) generated among long term non-progressors (LTNP) who might gain protective immunity against HIV-l through nef-deleted mutants, we have designed replication-defective recombinant HIV-1 particles pseudctyped with vesicular stomatitis virus glycoprotein (VSV-G), cariying an enhanced green fluorescent protein (EGFP) gene in place of the env. VSV-G pseudotyped virions had significantly augmented infectivity for both dividing and non—dividing cells, and EGFP enables single cell analysis to identify the infected cells producing viral antigen p24. These pseudotyped viral particles could also infect Herpesvirus saimiri-transformed human CD4+ T cells (HVS-T) to produce p24 antigen with or without the nef gene. Although the surface expression of CD4 and class I MHC molecules but not class II MHC, Fas and B7-2 molecules was down-modulated in T cells infected with pseudotyped virions expressing the nef gene, none of the above molecules were down-modulated in the cells infected with nef-deleted pseudotyped virions. VSV-G pseudotyped HIV-1 particles encoding the EGFP gene and HSV-T cells will be useful for analyzing the actual target molecules recognized by CTLs having protective capacity against HIV-l in vivo and thus, will open new paths for vaccine development.
