Human monocytic U937 cells kill Salmonella in vitro by NO-independent mechanisms

Nitric oxide (NO) has a central role in host defense against intracellular microbes. HLA-B27 has been shown to directly modulate host-microbe interact ion in vitro, leading to the impaired elimination of Salmonella in human mo nocytic U937 cells. Here, we studied whether impaired elimination of Salmon ella would result from differences in NO production between HLA-B27- and HL A-A2-transfected U937 cells. Both human monocytic transfectants produced NO equally well and killed Salmonella via NO-independent mechanisms.