Invasion of human fallopian tube epithelium by Escherichia coli expressing combinations of a gonococcal porin, opacity-associated protein, and chimeric lipo-oligosaccharide

The transepithelial migration of Escherichia coli that expressed all possible combinations of a plasmid-encoded gonococcal porin (Por), opacity-associated protein (Opa), and 3F11 lipo-oligosaccharide (LOS) epitope was investigated. Surface expression of Por mediated selective changes in E. coli antibiotic susceptibility, and coexpression of Opa and the 3F11 LOS epitope mediated bacterial clumping (P <.01). In the human fallopian tube organ-culture model, Opa-producing variants attached up to 44-fold better than control bacteria (P <.01), and Por-producing variants exceeded submucosal invasion of control bacteria by 500-fold (P <.01). Opa and Por each facilitated intracellular invasion 20-40-fold (P <.01). In dual expresser variants, the 3F11 LOS epitope markedly reduced attachment and invasion mediated by Opa or Por. The LOS inhibitory effect was curbed when all 3 factors were expressed, which suggests an additional interaction of the 3 factors at the bacterial surface. Por, Opa, and LOS play important roles in Neisseria gonorrhoeae trafficking across human fallopian tube epithelium.