Enhancement of HIV-1 infection by the capsular polysaccharide of Cryptococcus neoformans.

Patients with AIDS who become infected with Cryptococcus neoformans have a poor prognosis. We speculated that the presence of cryptococcal capsular polysaccharide may enhance HIV-1 infection. In an in-vitro study, the presence of cryptococcal polysaccharide significantly increased (p less than 0.05) production of p24 antigen after infection of H9 cells with HIV-1-infected H9 cells. We also found similar results when lymphocytes from an HIV-1-infected patient were co-cultured with mononuclear cells from an uninfected individual. Our findings suggest a new pathogenic role for the capsular polysaccharide--namely, the capacity to enhance HIV-1 infectivity.