Participation of the Intestinal Epithelium and Mast Cells in Local Mucosal Immune Responses in Commercial Poultry

ABSTRACT The intestinal mucosa of commercial poul-try is continually subjected to invasion or colonization by a wide array of potentially hostile enteric pathogens. Although, recent investigations have focused on lympho-cyte involvement in immune responses in the intestine, lymphocyte-mediated immunity alone will not explain the barrier nature of mucosal membranes associated with rejection of many enteric pathogens upon secondary ho-mologous challenge. Our laboratories have focused on nontraditional elements of mucosal immunity in poultry to better understand host-pathogen interactions in the intestine. Following classical and novel immunization procedures, we have identified an antigen-specific mech-anism of immediate responsiveness of the mucosal epi-thelium characterized by epithelial chloride secretion. This mechanism, characteristic of intestinal anaphylaxis, is mediated by local immune elements. Similar mecha-(Key words: mucosal immunity, intestinal epithelium, mast cell, antibody titer