Secretional Blockade by VSL#3 Figure 2. The inhibition of TNF-induced IP-10 secretion is mediated by a surface protein of L. casei. (A) Mode-K cells were stimulated for 24 h with L. casei, Lactobacillus plantarum 299v or E. coli Nissle 1917 (moi as indicated) with or without TNF (10 ng/ml) activation for 24 h. The concentration of IP-10 and IL-6 in cell culture supernatants was measured by ELISA. Bars represent mean values (+/2 SD) of triplicate samples. (B) Mode-K cells were stimulated with L. casei (moi 20) killed by formaldehyde fixation (fix), lysozyme (lys)-digestion or heat (heat)-treatment with or without TNF (10 ng/ml) activation for 24 h. (C) L. casei was treated with trypsin (try), proteinase K (pK) or phospholipase A (pA) followed by formaldehyde-fixation (fL.c). (D) TLR2 deficient as well as TLR2 expressing HEK293 cells (absence/presence of TLR2 in the cells was analysed by real- time PCR) were stimulated for 24 h with TNF (10 ng/ml) and L. casei (moi 20). IP-10 concentration was measured in the culture supernatants by ELISA. The bars represent mean values (+/2 SD) of triplicate samples. doi:10.1371/journal.pone.0004365.g002 PLoS ONE | www.plosone.org 5 February 2009 | Volume 4 | Issue 2 | e4365