The Study Of Mucosal Inductive Site (PPs) In Mucosa-associated Lymphoid Tissue In The Large Intestine Of Alxa Bactrian Camel

10Bactrian camels’ mucosa-associated lymphoid tissue (MALT) of thelarge intestine were comparatively studied by anatomical and histologicalmethods, and the ultrastructure of Peyer’s patches (PPs) with a scrotiformwhich were located on the mucosal surfaces of the ileocecal orifice wereobserved by the electron microscope. In order to explore all forms PPs withthe development, aging and atrophy characteristics,3Bactrian camel’s fetusand3old Bactrian camels’ MALT of the large intestine were comparativelystudied by anatomical and histological methods. Moreover, to explore thedivision of the inductive sites and the effector sites of the Bactrian camellarge intestinal mucosal immunity system, the SIgA plasma cells and the IgGplasma cells distributed in the Bactrian camel large intestine wererespectively studied by the immunohistochemistry method.The results showed that:(1) PPs were mainly located on the mucosalsurfaces of the entire ileocecal orifice, the beginning of the cecum and thefirst third of the colon. The shape of PPs gradually changed from"scrotiform" to "faviform" along the large intestine with the scrotiform PP asthe major type in the ileocecal orifice. The distribution density also graduallydecreased from the ileocecal orifice to the colon. The histologicalobservations further revealed that the MALT in the form of PPs or isolatedlymphoid follicles（ILF）and lamina propria lymphocytes was mainly presentin the lamina propria and submucosa from the entire ileocecal orifice, wherethe muscularis mucosa is usually incomplete, to the colonic forepart. Inaddition, lymphoid tissue was much more abundant in the lamina propria and submucosa of the ileocecal orifice as compared to the cecum and colon.Statistically, the MALT of the ileocecal orifice contained a higher number oflymphoid follicles (37.7/10mm2) than that of the cecum, colon or rectum(P<0.05).(2) Outside of the scrotiform PPs’mucosa with the ileocecal orifice,the glands are very crowded and their secretion are more exuberant whichcompared with the inside of them. However, the microfolds cells areobviously distributed at the inside of the scrotiform PPs’ mucosa.(3) Thedevelopment of Bactrian camels’ PPs in the large intestine began with thefetal period, but their structures are not mature. However, which obviouslyatrophy at the aging period.(4) Immunohistochemical staining resultsshowed the sIgA plasma cells and the IgG plasma cells were mainly locatedin the mucosa lamina proria of the Bactrian camel large intestine, and werearound the intestinal grand which were far away from the PPs. It indicatedthese sites are the effector sites of the Bactrian camel large intestinal mucosalimmunity system.In conclusion, there are rich PPs in the Bactrian camels’ largeintestinal mucosa, the development of Bactrian camels’ PPs in the largeintestine began with the fetal period, and peaked in middle-aged period, andsubsequently declined with age and when old period the PPs had severelyatrophied; The inductive sites of the Bactrian camels’large intestinal mucosalimmunity is the PPs which are at the entire ileocecal orifice, the beginning ofthe cecum and the first third of the colon. The scrotiform PPs are likely to theresult of long-term adaptation of the Bactrian camel to the harsh livingenvironment. Moreover, except the PPs’ area, the rest of the large intestinalmucosa is the effector sites.