ACIDIC SPHINGOMYELINASE MEDIATES ENTRY OF N-GONORRHEA INTO NONPHAGOCYTIC CELLS

Invasion of human mucosal cells by N. gonorrhoeae via the binding to h eparansulfate proteoglycan receptors is considered a crucial event of the infection. Using different human epithelial cells and primary fibr oblasts, we show here an activation of the phosphatidylcholine-specifi c phospholipase C (PC-PLC) and acidic sphingomyelinase (ASM) by N. gon orrhoeae, resulting in the release of diacylglycerol and ceramide. Gen etic and/or pharmacological blockade of ASM and PC-PLC cause inhibitio n of cellular invasion by N. gonorrhoeae. Complementation of ASM-defic ient fibroblasts from Niemann-Pick disease patients restored N. gonorr hoeae-induced signaling and entry processes. The activation of PC-PLC and ASM, therefore, is an essential requirement for the entry of N. go norrhoeae into distinct nonphagocytic human cell types including sever al epithelial cells and primary fibroblasts.