Expression of Mucins and Trefoil Factor Family Protein-1 in the Colon of Pigs Naturally Infected with Salmonella typhimurium

The expression patterns of different mucins (MUC1, MUC2, MUC4, MUC5AC, MUC5C and MUC6) and trefoil factor family protein-1 (TFF1) in the colon of healthy pigs and pigs naturally infected with Salmonella typhimurium is reported. Twenty infected pigs approximately 80-160 days of age from 20 different herds were studied. These animals had similar microscopical change in colonic tissue characterized by mucosal erosion or sloughing and acute inflammation. S. typhimurium was cultured from all lesions and the identity of each isolate was confirmed by serotyping. Immunohistochemical studies of colonic tissue revealed reduced expression of MUC4 on the surface of the cryptal epithelium of S. typhimurium-infected pigs compared with non-infected pigs (P<0.001). By contrast, colon from infected animals had increased expression of MUC5AC (P<0.0001) and TFF1 (P=0.0095) relative to controls and there was a significant positive correlation between expression of these two molecules (Spearman coefficient 0.64, P<0.0001). Further studies are needed to evaluate the functional relationship between altered expression of these molecules and inflammation in Salmonella-infected pigs.