MECHANISMS OF IMPAIRED ANTICRYPTOCOCCAL ACTIVITY OF MONOCYTES FROM DONORS INFECTED WITH HUMAN-IMMUNODEFICIENCY-VIRUS

The mechanisms by which monocytes from patients infected with human im munodeficiency virus (HIV) have reduced growth inhibitory activity aga inst Cryptococcus neoformans was examined, Monocyte-enriched periphera l blood mononuclear cells from 12 HIV-seropositive donors with CD4 cel l counts of 10-210 cells/mm(3) (median, 85) and HIV-seronegative donor s were compared in assays to determine the binding and phagocytosis of C. neoformans and the respiratory burst and degranulation in response to C. neoformans and zymosan. Monocytes from HIV-infected and uninfec ted persons bound and ingested C. neoformans equally well; however, ge neration of hydrogen peroxide and specific release of beta-glucuronida se in response to C. neoformans was significantly reduced in monocyte- enriched cells from the HIV-infected donors, The impaired anticryptoco ccal activity of monocytes from persons with HIV may be related to def ects in both oxidative and nonoxidative effector pathways that occur a fter the binding and internalization of the organism.