UMBILICAL-CORD BLOOD MONONUCLEAR CELL HIV-1 LTR BINDING ACTIVITIES

Vertically transmitted HIV disease constitutes a significant problem i n pediatrics, In order to characterize some of the possible host facto rs involved in HIV replication in fetuses and newborns, we surveyed th e HIV-1 LTR binding factors present in nuclear extracts from cord bloo d mononuclear cells. A series of electrophoretic mobility shift assays (EMSAs) showed that protein extracts from cord blood interacted with several regions of the HIV LTR, The most prominent binding activities involved the NF-kB sites, but other regions of the LTR also showed fac tor binding with the cord blood extracts, Some of these cord blood ext ract binding activities displayed qualitative differences when compare d to adult peripheral blood mononuclear cell extracts in EMSA and UV c ross-linking studies, Transient transfection experiments indicated tha t the NF-kB and Spl sequences were important for wild type levels of e xpression in cord blood cells, but that additional sequences 5' to the NF-kB sites also contributed activity. Thus, factors that interact wi th many of the well-known HIV LTR regulatory sites are present in cord blood cells. However, certain qualitative differences distinguished c ord blood and adult peripheral blood binding activities and these may contribute to pathogenesis of HIV infection in neonates.