FUNCTIONAL DEFICIENCIES IN 2 DISTINCT INTERFERON-ALPHA-PRODUCING CELL-POPULATIONS IN PERIPHERAL-BLOOD MONONUCLEAR-CELLS FROM HUMAN-IMMUNODEFICIENCY-VIRUS SEROPOSITIVE PATIENTS

Two populations of IFN-alpha producing cells (IPC) were examined to de termine whether they are coordinately dysregulated in human immunodefi ciency virus (HIV) disease. IFN-alpha produced in response to herpes s implex virus (HSV) and Sendai virus (SV) was measured and the frequenc ies of the IPC were obtained by ELISpot assay. IPC that respond to HSV (natural IFN-alpha producing cells) and those responding to SV (predo minantly monocytes) were present, on average, at 7.6 and 138 per 10(4) PBMC in healthy controls, respectively, More patients had a reduced I FN-alpha response to HSV than to SV, and individual patients did not s how a decreased response to SV without a decreased response to HSV. Ne ither IPC function was correlated with CD4(+) cell levels. We conclude that the defects in IFN-alpha production in these two cell population s arise independently, possibly due to differences in susceptibility t o HIV infection or molecular regulation.