Effect of Lactobacillus casei on serum interleukins following enteropathogenic E. coli infection in experimental rabbits

Abstract

In the present study we investigated the pro-inflammatory and anti-inflammatory effect of Lactobacillus casei following infection with multi-drug resistant enteropathogenic Escherichia coli infection in experimental rabbits. For this purpose, 40 adult rabbits were divided into different groups and were infected with multi-drug resistant E. coli AZ1 strain except the control groups. The rabbits were orally administered with L. casei SABA6 strain in two different ways i.e. pre-treatment and post-treatment and both were continued for 7 days. The rabbits were sacrificed sequentially at 0, 4, 7 and 10 days post infection (dpi). Serum and intestinal tissue samples were collected from each rabbit. Intestinal tissue samples were subjected to histopathological examination that showed microscopic lesions at 4 and 7 dpi among infected group. The serum samples were processed for determination of Interleukin-6 (IL-6, pro-inflammatory) and Interleukin10 (IL-10, anti-inflammatory) using ELISA. It was found that oral administration of L. casei SABA6 reduces the eruption of intestinal epithelial cells and reduces the incidence of diarrhea. Further, L. casei SABA6 also resulted in immuno modulation by significant increase in concentration of IL-6 and IL-10 particularly at 4 and 7 dpi and protects against E. coli AZ1 infection. Altogether, it was concluded that increased IL-6 and IL-10 levels were responsible for protection against EPEC infections. The sequential sacrifice of experimental animals could be adopted for future studies to find out pathogenesis and virulence mechanism of EPEC infections along with protective efficacy of different probiotics.