DISTRIBUTION OF HIV TYPE-1 (HIV-1) IN BLOOD COMPONENTS - DETECTION AND SIGNIFICANCE OF HIGH-LEVELS OF HIV-1 ASSOCIATED WITH PLATELETS

BACKGROUND: Although inactivation of enveloped viruses transmitted by plasma derivatives has been successful, no methods for virus inactivat ion or removal have been established for platelet concentrates or red cell (RBC) components. Relatively little is known regarding the extent or significance of virus interactions with the cellular constituents in these components. STUDY DESIGN AND METHODS: Units of whole blood we re collected from six HIV type 1 (HIV-1)-positive, asymptomatic indivi duals and separated into peripheral blood mononuclear cells (PBMNCs), cell-free plasma, white cell-reduced platelet concentrate, and white c ell-reduced RBCs. DNA and RNA polymerase chain reaction and virus cult ure methods were used to study the compartmentalization of HIV-1 immed iately after component preparation and after storage. RESULTS: As expe cted, HIV DNA and infectious virus were detected in fresh blood and in PBMNCs, and virion-associated RNA was detected in fresh plasma from a ll six donors.The levels of viral nucleic acids in these preparations remained relatively stable with 4 degrees C storage, whereas infectivi ty of PBMNCs was rapidly lost. Washed RBCs tested negative for HIV in all assays at all time points. Platelets retained high levels of HIV R NA (but not Infectivity) after extensive washing, as Lyell as after st orage at 4 and 22 degrees C. High-level platelet-associated HIV-1 was also demonstrated in samples collected during early seroconversion. Pe riseroconversion and postseroconversion levels of platelet-associated HIV-1 correlated with the level of plasma viremia and with the rate of progression to AIDS. Cell-free virus from donor plasma and tissue cul ture fluid rapidly and firmly attached to platelets from noninfected d onors. Infectivity of tissue culture virus bound to platelets was demo nstrated in vitro.CONCLUSION: Significant levels of HIV-1 are associat ed with platelets during all stages of infection. Platelet-associated HIV could either mediate virus clearance or facilitate virus dissemina tion and expanded tropism. Finally, virus inactivation research must a ddress virus associations with platelets.