Porins from Salmonella enterica serovar Typhimurium induce TNF-alpha, IL-6 and IL-8 release by CD14-independent and CD11a/CD18-dependent mechanisms.

Lipopolysaccharide (LPS) of Gram-negative bacteria and several surface components of Gram-positive bacteria utilize CD14 and CD11a/18 as cellular receptors to induce expression and release of cytokines. Of the surface components of Gram-negative bacteria, porins exhibit a biological activity similar to that of LPS. The results in this paper show that the mechanism of stimulation by porins of THP-1 cells enriched in CD14 receptor after treatment with 1,25-dihydroxyvitamin D(3) (vitamin D(3)) is independent of this receptor, but is partially dependent on CD11a/18 integrins.