Intestinal and Mucosal Microbiomic Response to Oral Challenge of Enterotoxigenic Escherichia Coli in Weaned Pigs

Abstract

Enterotoxigenic Escherichia coli (ETEC) is closely associated with diarrhoea in children in resource-limited countries and of travellers’ diarrhoea. This study aims to investigate the change of ileal mucosal microbiome and ileal protein expression as well as their correlation in pigs by E. coli K88 (ETEC). Seven weaned male pigs were orally given 1 ×109 CFU of ETEC (ETEC, n = 7), and the other seven received saline (CON, n = 7). Ileal tissues were obtained 48 h after the ETEC challenge for both proteomic and mucosal microbiomic analyses. Nine proteins were altered in expression level in the ETEC group, including decreased expression of FABP1 and FABP6 involved in bile acid circulation. TLR-9 mediated pathway was also affected at transcription level with increased expression of SIGIRR and MyD88. Correlation analysis revealed correlations between the ileal proteins and mucosal bacterial taxa, including the positive correlation between Lactobacilli and PPP3CA (r = 0.9, p < 0.001), and negative correlation between Prevotella with CTNND1 (r = -0.7, p < 0.01). In conclusion, ETEC infection caused inflammation and impaired the circulation of bile acids, and the mucosal microbiome may affect the expression of intestinal proteins. Further studies are needed for exact roles of these affected processes in the pathogenesis of ETEC-triggered diarrhoea.

IgYs: on her majesty’s secret service

“…The analysis of hen yolk antibodies included not only IgY activity and stability but also tests in mice, which showed a significant inhibition of cell adhesion in two of the three strains tested, as analyzed on the basis of PCR detection of ETEC-specific enterotoxin primers ( 188 ). The fusion plasmids that included three copies of pig-derived enterotoxigenic E. coli (K88ac) flagellar gene (fliC) or two copies of human enterotoxigenic E. coli fliC gene were also used to produce the recombinant proteins and further applied for hen immunization, resulting in specific antibodies production presenting the ability to inhibit the bacteria adhesion to the intestinal porcine enterocytes (IPEC-J2) ( 261 ) or showing in vivo anti-adherent activity in mice ( 262 ). In another example, the K88ac strain was a source of adhesin gene faeG and, together with adhesin gene fedF of strain F18ac, was used for recombinant fusion protein production.…”