TGFB1 and infection: When intestinal monolayers were pre-exposed to the recombinant L. paracasei probiotic expressing LAP, followed by infection with L. monocytogenes, a 44%, 45%, and 46% reduction in adhesion, invasion, and transepithelial translocation, respectively, was observed.234 A Lactobacillus casei ATCC 334 strain was also engineered to produce LAP from a nonpathogenic strain of Listeria innocua and pathogenic strain of L. monocytogenes on its surface.