ROLE OF HIV-1 PHENOTYPE IN VIRAL PATHOGENESIS AND ITS RELATION TO VIRAL LOAD AND CD4-CELL COUNT( T)

The predictive value of HIV-1 phenotype in peripheral blood mononuclea r cell (PBMC) coculture and the relation among viral phenotype, vira I load, and CD4+ T-cell count were examined in two studies. In study A, 132 HIV-l-infected individuals were examined retrospectively for the relation between the result of their initial HIV cultivation in PBMC c oculture and survival rate 6 years later. In study B, 176 patients wer e examined since 1994 for markers of HIV disease progression. HIV-I ph enotype was determined by PBMC cocultivation, viral load by NASBA HIV RNA QT System, and CD4+ T-cell count by flow cytometry. In study A, th e percentage of survival for patients with initial negative virus cult ure was significantly higher (95%) than in patients with nonsyncytia-i nducing (NSI) isolates (78%) and syncytia-inducing (SI) isolates (21%) (P < 0.05 and P < 0.0001, respectively). When SI phenotype was subdiv ided into moderately cytopathogenic and highly cytopathogenic, signifi cant differences in the rate of survival between these subgroups could be observed (45% vs. 14%; P < 0.05). In study B, progression from neg ative virus culture to the isolation of NSI variants was associated wi th increasing viral load (P < 0.0001) but did not affect CD4+ T-cell c ount significantly (P > 0.07), whereas the switch from NSI to SI virus was accompanied by significant decline of CD4+ T-cells (P < 0.0001) b ut no change in viral load (P > 0.21). Thus, isolation and phenotyping of HIV represents an additional striking predictive marker for progre ssion of HIV infection. J. Med. Virol. 56:259-263, 1998. (C) 1998 Wile y-Liss, Inc.