Asparagine residue altering it to proline in the 68th (N68P), 73rd (N73P) or 211th (N211P) residue [Supplementary Table 3]. SW480 or COS7 cells transfected with any in the CETP manufacturer CHI3L1 mutant plasmids showed a similar pattern of protein expression and localization compared to CHI3L1 WT [Supplementary Figure 5A]. Western blot evaluation confirmed that only N68P affects correct CHI3L1 glycosylation [Figure 5B]. Overexpression of CHI3L1-mutant plasmid N68P, which lacks N-glycosylation, in SW480 cells with subsequent infection with AIEC COX-2 Synonyms LF82-WT strain resulted in significantly less bacterial association, as compared to cells overexpressing WT or CHI3L1 mutant N211P, which have conserved N-glycosylation [Figure 5C]. We additional investigated how CHI3L1 N68P mutant-overexpressing cells responded to unique chiA mutants by overexpressing N68P- or N211P-mutant CHI3L1 or WT CHI3L1 in IECs after which infecting the cells with LF82-WT or the four LF82 mutants. There was drastically increased bacterial adhesion with LF82-WT and -chiA/chiALF82 in CHI3L1WT-overexpressing cells, too because the N211P mutant CHI3L1-overexpressing cells [Figure 5D, Supplementary Figure 5B]. Bacterial counts inside the groups infected together with the other mutant LF82 strains (LF82-chiA, -chiA/chiAK12 and -chiA/chiALF82-5MU) remained drastically reduce. On the other hand, there was no apparent difference in bacterial association across all groups of infected cells that overexpressed CHI3L1 mutant N68P. This indicates that N-glycosylation in the single 68th asparagine residue in mouse CHI3L1, which corresponds to human CHI3L1 60th asparagine residue, is important for ChiA-mediated host/ microbial interactions.NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author ManuscriptGastroenterology. Author manuscript; readily available in PMC 2014 September 01.Low et al.PageLF82 ChiA plays a crucial role in efficient infection in the host and in exacerbating infectious colitis in vivo To further confirm our in vitro findings and investigate the in vivo relevance in the observed virulence of LF82-WT and its four chiA mutants, 80-week-old C57Bl/6 mice have been given 1.five DSS in their drinking water to induce mild intestinal epithelial harm, and orally gavaged with 108 LF82-WT or its 4 chiA mutants for 15 consecutive days. The body weight of every mouse was monitored every day. Mice infected with LF82-WT or -chiA/ chiALF82 strains did not show any indicators of weight recovery till the endpoint and had larger clinical scores [Figure 6A]. Conversely, LF82-chiA, -chiA/chiAk12- or -chiA/ chiALF82-5MU-infected mice also as uninfected mice showed recovery just after DSS day ten, with milder clinical scores [Figure 6A]. On therapy day 7, LF82-WT-infected mouse stools contained the highest quantity of bacteria as compared to all the other groups of mice [Figure 6B]. On day 14, the stool bacterial count was highest in mice infected with either LF82-WT- or -chiA/chiALF82. Bacteria translocation assays revealed that only LF82-WT- and -chiA/chiALF82-infected mice showed appreciable bacterial counts within the liver, spleen, mesenteric lymph nodes (MLNs) and colon [Figure 6C], in association with drastically reduced colonic length as when compared with the other groups [Supplementary Figure 6A]. Colonic production of CHI3L1 was up-regulated soon after DSS treatment with or with no AIEC infection [Supplementary Figure 6B]. Furthermore, colonic histological sections clearly showed severe colitis improvement in LF82-WT and -chiA/chiALF82-infected mice, with large quantity of.