HIV-2 INFECTION IN 12 EUROPEAN RESIDENTS - VIRUS CHARACTERISTICS AND DISEASE PROGRESSION

Objective: To assess the disease progression rate among 12 HIV-2-infec ted West European residents (nine of West African descent), compared w ith the disease progression rate among HIV-1-infected individuals of t he same population, and the characteristics of the HIV-2 strains invol ved. Methods: HIV-2-infected individuals were identified by commercial ly available serological assays, their clinical status and CD4+ cell c ounts were monitored, and HIV-2 was isolated from their peripheral blo od mononuclear cells. T-cell-line tropism and syncytium-inducing capac ities of the isolated viruses were determined and their phylogenetic r elationships were analysed by comparing polymerase chain reaction-ampl ified nucleotide sequences of reverse transcriptase (RT) gene segments . Results: Eight of the 12 HIV-2-infected individuals presented with p rogressive disease and one of them progressed from Centers for Disease Control and Prevention group A1 to A3 within 36 months after seroconv ersion. The ratios of asymptomatic versus symptomatic individuals amon g residents of the Rotterdam region of West African descent were 2:7 f or HIV-2 and 8:9 for HIV-1-infected individuals. HIV-2 was isolated fr om six of the nine individuals with progressive disease. The time requ ired for virus isolation correlated inversely with the individuals' CD 4+ cell counts. Five of the HIV-2 isolates replicated in immortalized T-cell lines, and two isolates from patients with AIDS were syncytium- inducing. Five HIV-2 isolates from patients born in the Cape Verdian I sles grouped together within subtype A. The HIV-2 isolate from a patie nt of Ghanese origin belonged to subtype B. Mutations were identified in the RT genes from HIV-2 isolates of two zidovudine-treated patients , one of which has also been shown to be involved in zidovudine resist ance in HIV-1. Conclusion: Disease progression in HIV-2 infection may be as rapid as in HIV-1. HIV-2 isolation and viral phenotype were rela ted to disease status, and mutations identical to those observed in HI V-1 zidovudine resistance were observed in patients treated with zidov udine.