Morphological Study On Mucosa-associated Lymphoid Tissue Of Digestive Tract In Juema Pig

Juema pig is a rare breed peculiar to the plateau in China.In order to broaden the research ideas of juema pig,and supplement the research gap in the Gut-associated lymphoid tissue(GALT)of juema pig.As an object,the morphology of the digestive tract mucosa-associated lymphoid tissues of 8 juema pigs was analyzed in detail through anatomy and histology,which involved the anatomical structure and general histology of lymphoid tissues of the digestive tract mucosa of juema pigs.Characteristics,distribution of goblet cells and mast cells,distribution of IgA and IgG secreting cells,and the use of electron microscopy to observe and analyze the ultrastructure of lymphoid tissues related to the digestive tract mucosa of juema pigs.The specific research results are as follows:1.Anatomy characteristics of GALTThe relevant lymphoid tissues observed on the surface of the digestive tract mucosa of juema pigs were mainly mature lymphoid tissues(Peyer’s patches,PPS).PPS is more widely distributed in the stomach,jejunum,and colon.There is no significant difference in the data among the three(P> 0.05).There is less distribution in the ileum,cecum and rectum.No PPS was found in the duodenum.The shape of stomach to ileum PPS changed from honeycomb to strip,and the shape of ileum to rectum PPS changed from strip to button.2.General histological characteristics of GALTJuema pig’s GALT is located in the submucosa and lamina propria,mainly containing mature lymphoid tissue(PPS),solitary Isolated Lymphoid Follicles(ILFS)and Cryptopatches(CPS).It is found in the stomach,duodenum,cecum and rectum.The submucosa and lamina propria are mostly ILFS and CPS,and the submucosa and lamina propria of jejunum,ileum,and colon are mostly PPS.Lymph tissue is surrounded by collagen fiber network around the follicles.The number and area of lymphatic follicles per unit area of GALT and the area of lymphocytes and collagen fibers in the unit field of view showed a trend of increasing and then decreasing in the digestive tract of juema pigs,and reached a peak at the ileum.3.Distribution of mast cells and goblet cellsThe goblet cells in the gastrointestinal mucosa of the juema pig are mainly distributed in the glands of the lamina propria,with fewer developed goblet cells in the glands in the stomach,and most developed goblet cells in the duodenal glands.The area of sigmoid cells is the largest,which is significantly higher than that of other parts(P <0.05).The intestinal glands from the duodenum to the ileum protrude into the intestinal cavity to form intestinal villi.The glands are densely arranged in a single tube shape,no intestinal villi are formed,and goblet cells increase.The mast cells in the digestive tract mucosa of the juema pig are mainly distributed around the crypts of the intestinal gland of the propria and around the blood vessels in the lymphoid follicle area,and a small amount is distributed in the submucosa.The trend of decrease after increase is maximum in the ileum.4.Distribution of IgA-secreting cells and IgG-secreting cellsThe IgA and IgG-secreting cells in the digestive tract mucosa of the juema pig are diffusely distributed in the lamina propria,the lamella propria are distributed around the crypts of the lamina propria,and are less distributed near the intestinal cavity.The epithelium and germinal center are distributed in a small amount,and the lymph follicle center and basal part are rarely distributed.The content of IgA-secreting cells in the digestive tract mucosa of juema pigs was significantly higher than that of IgG-secreting cells.Except for the ileum and cecum,the area of IgA and IgG-secreting cells in the non-GALT region in the same part was higher than that of GALT region.The distribution of IgA-secreting cells and the distribution of IgG-secreting cells were basically the same between the various parts of the digestive tract.5.Ultrastructure characteristics of GALTScanning electron microscope observation revealed that a large number of M cells can be clearly observed on the surface of the GALT mucosa of the juema pig,and there are irregularly arranged and short sparse microvilli on the surface of the M cells that are different from the microvilli structure on the surface of the intestinal mucosa.Transmission electron microscopy observation revealed that lymphocytes were mainly present in GALT of juema pigs,while granulocytes,mast cells,and plasma cells were distributed in small amounts.M cells,goblet cells,Parnett cells,and lymphocytes were clearly observed in the lamina propria.In summary,the GALT in the digestive tract of juema pigs differs in terms of quantity,morphology,etc.due to their different locations.The structure and function of GALT in the ileum is the most complete,reflecting the organization and maturity of lymphatic tissue in this area.Although GALT accounts for a small proportion in the entire digestive tract,it exerts a strong immune function without affecting the digestive and absorption functions,dominates the immune regulation of the entire digestive tract,and reflects the specificity of GALT in mucosal immunity and importance.