Chicken egg yolk antibodies (IgY) modulate the intestinal mucosal immune response in a mouse model of Salmonella typhimurium infection

This study determined the effects of chicken egg yolk antibodies (IgY) on immune responses in the intestinal mucosal of mice infected with Salmonella typhimurium. Sixty, 28-day-old mice were divided into 4 groups and treated with streptomycin or sterile water for 2 days followed by 1 day without treatment. The control group was unchallenged whereas the mice in the other three groups were treated twice with 10(9) CFU mL(− 1)S. typhimurium. For the next 3 days, control mice continued to receive no treatment whereas the mice in the remaining three groups were orally administered with 20 mg mL(− 1) of specific IgY, 20 mg mL(− 1) of nonspecific IgY or PBS. S. typhimurium activated gut-associated lymphoid tissue, increasing the release of IFN-γ and TNF-α in the mucosa and increased the number of activated T-lymphocytes and cytotoxic T-γδ. Specific IgY attenuated the increase in IFN-γ and TNF-α and the decrease in IL-10. S. typhimurium induced mobilization of CD8(+) and CD8(+) TCRγδ T cells in the epithelium and CD4(+) and CD8(+) T cells in the lamina propria reflecting an inflammatory process that was attenuated by IgY. These results suggest that specific IgY modulates intestinal mucosal immune responses during a S. typhimurium infection.