ANTIVIRAL IMMUNITY IN HIV-1-INFECTED LONG-TERM NONPROGRESSORS (LTNPS)

Now that the acquired immunodeficiency syndrome (AIDS) epidemic is wel l into its second decade, it has become evident that a small percentag e (approximately 5%) of HIV-infected individuals do not experience pro gression of HIV disease even after several years of being infected wit h HIV. These individuals have been designated as 'long term non-progre ssors' (LTNPs). From a virologic standpoint, these LTNPs have low vira l burden in mononuclear cells, but persistent virus replication as man ifested by chronic and generally low levels of plasma viremia. From an immunologic standpoint, immune functions including CD8(+) T-cell- and CD4(+) T-cell-mediated functions are preserved. In addition, they sho w a vigorous humoral immune response. More importantly, lymphoid tissu e structure and function are preserved in LTNPs. Despite persistent lo w-level virus replication and chronic stimulation of the immune system , immune activation is qualitatively and quantitatively different in L TNPs compared to that observed in HIV-infected individuals whose HIV d isease has progressed. (C)1996 Academic Press Ltd