Significance of plasma and peripheral blood mononuclear cell derived HIV-1sequences in establishing epidemiologic linkage between two individuals multiply exposed to HIV-1

Establishing epidemiologic linkage in individuals multiply exposed to HIV c an be a difficult task. To date, only peripheral blood mononuclear cell (PB MC)-derived sequences have been used in studying HIV-1 transmission between individuals. So far, the combined utility of plasma and PBMC-derived HIV-1 sequences has not been assessed in establishing epidemiologic linkage in p eople involved in transmission of HIV. In this study, both PBMC (DNA) and p lasma (RNA) derived viral quasispecies was used in establishing epidemiolog ic linkage between two infected individuals (B-90 and B-69) multiply expose d to HIV-1 via injecting drug use. A detailed sequence, and phylogenetic an alyses of HIV-1V3 region quasispecies derived from these two compartments c learly demonstrated compartmentalization of viral quasispecies between PBMC and plasma. More importantly, these data also demonstrate that in order to establish epidemiologic linkage between individuals multiply exposed to HI V-1, analyses of viral strains from both plasma and PBMC compartments may b e necessary. The PBMC compartment alone may not provide sufficient informat ion on epidemiologic linkage, overall diversification of viral quasispecies , replacement of older strains and the emergence of new viral recombinant s trains in vivo. These are the first analyses that demonstrate the increment al value of plasma derived sequences, when used in conjunction with PBMC-de rived sequences, in establishing the epidemiologic linkage between individu als multiply exposed to HIV parenterally. Further, the plasma derived HIV-1 sequences may prove to be invaluable in predicting a recent transmission b etween two epidemiologically-linked individuals. (C) 1999 Academic Press.