RT Journal Article SR Electronic(1) A1 Krakauer, Teresa A1 Peters, CJYR 1993 T1 Lipopolysaccharide inhibits the production of lymphocytic choriomeningitis virus in a human monocytic cell line JF Journal of General Virology, VO 74 IS 8 SP 1653 OP 1656 DO https://doi.org/10.1099/0022-1317-74-8-1653 PB Microbiology Society, SN 1465-2099, AB The human monocytic cell line THP-1 was used as a model to study the mechanism of infection in the monocyte/macrophage, a natural target of lymphocytic choriomeningitis virus (LCMV) infection in vivo. Both the virulent strain, LCMV. WE, and the avirulent strain, LCMV. ARM, infected THP-1 cells, but did not stimulate THP-1 cells to secrete interleukin 1 (IL-1) or tumour necrosis factor (TNF-α). When lipopolysaccharide (LPS) was added to THP-1 cells together with LCMV, an 80 to 90% reduction in the number of infected cells (measured by immunofluorescence) and a 90% reduction in viral plaques was observed 5 to 6 days postinfection. Neither interferon α (IFN-α) nor IFN-β were detected in supernatants from THP-1 cells after the addition of LCMV, LPS, or LPS plus LCMV. In contrast, the same levels of IL-1 and TNF-α were observed in the presence of LPS and LCMV, or LPS alone. However, antibodies to IL-1, TNF-α, interleukin 6 and IFN-α did not block the antiviral effect of LPS. In kinetic studies, LPS added 1 day after adding LCMV to THP-1 cells was still effective in reducing the number of infected cells. Our findings suggest that LPS alters cellular metabolism, possibly through the induction of IFN-α, and that IFN-α in the absence of LPS suppresses virus production., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-74-8-1653