Geonnotti, Anthony RBilska, MiroslawaYuan, XingOchsenbauer, ChristinaEdmonds, Tara GKappes, John CLiao, Hua-XinHaynes, Barton FMontefiori, David C2011-04-152010-03https://hdl.handle.net/10161/3301Bacterial lipopolysaccharide (endotoxin) is a frequent contaminant of biological specimens and is also known to be a potent inducer of beta-chemokines and other soluble factors that inhibit HIV-1 infection in vitro. Though lipopolysaccharide (LPS) has been shown to stimulate the production of soluble HIV-1 inhibitors in cultures of monocyte-derived macrophages, the ability of LPS to induce similar inhibitors in other cell types is poorly characterized. Here we show that LPS exhibits potent anti-HIV activity in phytohemagglutinin-stimulated peripheral blood mononuclear cells (PBMCs) but has no detectable anti-HIV-1 activity in TZM-bl cells. The anti-HIV-1 activity of LPS in PBMCs was strongly associated with the production of beta-chemokines from CD14-positive monocytes. Culture supernatants from LPS-stimulated PBMCs exhibited potent anti-HIV-1 activity when added to TZM-bl cells but, in this case, the antiviral activity appeared to be related to IFN-gamma rather than to beta-chemokines. These observations indicate that LPS stimulates PBMCs to produce a complex array of soluble HIV-1 inhibitors, including beta-chemokines and IFN-gamma, that differentially inhibit HIV-1 depending on the target cell type. The results also highlight the need to use endotoxin-free specimens to avoid artifacts when assessing HIV-1-specific neutralizing antibodies in PBMC-based assays.en-USAntibodies, MonoclonalAntibodies, NeutralizingCell Line, TumorChemokines, CCEquipment ContaminationEscherichia coliHIV InfectionsHIV-1HumansInterferon-gammaLeukocytes, MononuclearLipopolysaccharidesNeutralization TestsSalmonella entericaJournal article1931-8405