Alterations in peripheral blood B-cell populations in SHIV89.6P-infected macaques (Macacca fascicularis).

In addition to CD4+ T cell depletion, the B cell compartment of HIV-infected patients exhibits abnormalities, including deficits and diminished responses to ex vivo antigenic stimulation and in vivo vaccination. We used chimeric simian-human immunodeficiency virus (SHIV) infection of cynomolgus macaques to determine the dynamics of peripheral blood B cell alterations in this model of HIV infection. During the course of infection, we observed progressive loss of total and memory (CD27+) B cells, increased percentages of activated (CD95+) B cells, hypergammaglobulinemia, and deficits in the CD21+ B cell population. In addition, we noted declines in subsets of memory B cells, including both IgM+ and class-switched (IgD-IgM- CD27+) cells, with sustained deficits in the IgM+ memory (IgM+CD27+) B cell population. The similarity of the B cell alterations in these studies to those observed in HIV+ subjects supports the utility of the SHIV macaque model for examination of HIV-related B cell dysfunction.