Failure of Insulin-like Growth Factor Type I to Suppress HIV Type 1 in Adult or Umbilical Cord Mononuclear Blood Cells

Insulin-like growth factor type I (IGF-I) has been used as a treatment for cachexia in adults with AIDS and has been reported to show inhibitory activity against HIV-1_IIIB in cord blood mononuclear cells (CBMCs) in vitro at low-concentration (1%) fetal bovine serum (FCS). We evaluated the effect of IGF-I on MN, IIIB, and BaL strains, as well as on a patient isolate of HIV-1 in CBMCs and adult peripheral blood mononuclear cells (PBMCs). IGF-I failed to show any inhibitory effect on HIV replication in CBMCs or adult PBMCs under various culture conditions. In contrast to an earlier report of an antiviral effect, IGF-I augmented HIV-1 replication in PHA-stimulated PBMCs maintained in a low concentration of FCS.