Direct evidence for involvement of NF-kappa B in transcriptional activation of tumor necrosis factor by a spirochetal lipoprotein

Variable major lipoprotein (Vmp) is a major tumor necrosis factor (TNF)-ind ucing component of Borrelia recurrentis, the agent of louse-borne relapsing fever. B. recurrentis Vmp rapidly stimulates nuclear translocation of NF-k appa B and proinflammatory cytokine gene expression in the human monocyte-l ike cell line MonoMac 6. By overexpressing disabled mutant I kappa B alpha in MonoMac 6 cells cotransfected with a reporter gene, we provide evidence that NF-kappa B is essential for the transcriptional activation of TNF in t his system.