DETECTION OF UNINTEGRATED HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 DNA IN PERSISTENTLY INFECTED CD8+ CELLS

The presence of unintegrated viral DNA has been reported in cells pers istently infected by lentiviruses. including human immunodeficiency vi rus type 1 (HIV-1). We confirm that CD8+ cells can be productively and persistently infected by HIV-1 for up to 4 months, as determined by s ecretion of viral core antigen p24 into the extracellular medium and b y indirect immunofluorescence. The expression of the external viral gl ycoprotein gp120 at the surface of these cells was demonstrated by two -colour flow cytometry. Progeny virions recovered from CD8+ cells were infectious in CD4+ T cells. Despite an absence of significant cytopat hology, these chronically infected CD8+ cells were shown to harbour un integrated HIV-1 DNA, as detected by quantitative PCR. Both linear and circular forms of the extrachromosomal viral genome were present in i nfected CD8+ cells, as early as 3 weeks before a peak in viral replica tion. These findings provide evidence that the presence of unintegrate d viral DNA during lentiviral infection may not always correlate with c.p.e.