Porcine gut mucosal immunity-Interaction of inductive and effector components of galt

Mucous membrane is the second largest organ after skin in terms of the surface area. The mucous membrane throughout the body is effectively protected by means of lymphoid tissue aggregates present in the lamina propria or tunica submucosa. The small and large intestine which not only deals with the macromolecules related to the body nutrition but also need to encounter the gut commensals, pathogenic bacteria, virus or food toxins. These whole tasks of local immunity are accomplished by means of the gut-associated lymphoid tissue (GALT). The organisation pattern of the GALT and their different components are responsible for immune protection or immune tolerance, wherever necessary. The histocompartmentalisation of the GALT of small and large intestine and their relation to systemic immunity is one major area of research for evaluating the feasibility of alternate route of vaccination to contain various gut ailments. GALT comprises two prime components: induction site and effector site. Inductive site comprises the GALT, that is, Peyer's patches (PP) of small intestine and solitary lymphoid nodules of the large intestine. The induction of the mucosal immunology is triggered by means of trapping of particulate antigen by the M cells present in the follicle associated epithelium of the GALT. The presentation of antigen by the dendritic cell and other antigen presenting cells stimulate the activation of subsets of B and T cell found in the lamina propria, lymphoid follicles and interfollicular areas (IFAs) of the GALT. The study of this interaction of the inductive and effector site of GALT is of particular importance for effective immune protection at the local level and on the systemic immunity. Several works have carried out on different aspects of the GALT of porcine intestine as it is not only an economically important species, but also utilised as animal model for human. As such, the research pertaining to the development of mucosal vaccines is targeted on development of suitable vaccine candidate for retrovirus, colorectal cancer; or vaccine delivery agents to contain gut ailments of human and animals. This review is intended to summarise few important and basic aspects of porcine gut mucosal system.