PERSISTENCE OF SIMIAN IMMUNODEFICIENCY VIRUS MNE VARIANTS UPON TRANSMISSION

In macaques infected with a clone of simian immunodeficiency virus (SI V) Mne, viral variants consistently evolve multiple new potential glyc osylation sites in the first variable region (V1) prior to the develop ment of AIDS. In the present study, we asked whether viruses with thes e glycosylation sites persist when they are transmitted to a naive mac aque. Variants that evolved after transmission to a recipient macaque were compared with virus that evolved in the donor, which had been inf ected by cloned SIV Mne. Upon transmission, the specific serine/threon ine-rich motifs potentially encoding novel O-linked glycosylation site (s) in V1 were conserved in virus isolated from lymph node, spleen, an d liver tissue from the recipient. There was some accumulation of chan ges in V3 of envelope in virus from the recipient, whereas changes in this region were not observed in virus from the donor macaque. Some va riants detected in the tissue of the recipient at necropsy were most c losely related to viruses present in the donor inoculum even though th ese particular variants were not detected early after infection in the recipient's peripheral blood mononuclear cells. Overall, virus with t he predominant V1 sequences associated with progression to disease are transmitted to and persist in the recipient animal.