Study On The Distribution Characteristic S Of DC And CD68Marked By Different Phenotypes In The Small Intestinal MALT And MLN Of Bactrian Camels

Confirm the distribution characteristic of the dendritic cells (DC) andmacrophages (Mφ) in the small intestinal mucosa associated lymphoid tissues (MALT)and mesenteric lymph nodes (MLN) of the Bactrian Camels and establish themorphological basis by discussing them how to play the immune function in the smallintestinal MALT and MLN. With the SABC immunohistochemical technique(CD11c、CD103、FDC and CD68), the different phenotypes(CD11c、CD103、FDC and CD68)of DC and Mφ distributing in the different positions of the small intestinal mucosaand MLN from10adult Bactrian camels were located and observed. Results showed:(1) The distribution characteristics of different molecular markers of DC in the smallintestine MALT: The CD103+DC was widely distributed in the lamina propria of thesmall intestine of the Bactrian Camels. It was mainly distributed in intestinal villusand PPs with a few distributed in Lamina propria diffuse lymphoid tissue. theprotuberances of the CD103+DC within the intestinal villus、the surrounding of theintestinal glands and the paracortical areas of PPs were obvious, but were not obviousin the lymphoid nodule; The CD11c+DC was mainly distributed in the PPs, but rarelydistributed in the lamina propria of the small intestine. The shape of the CD11c+DCthroughout the small intestine was large, round and the protuberances were notobvious. their shapes were similar with the CD103+DC in the lymphoid nodule. TheFDC-SP+DC were diffusely distributed among the B lymphocytes and theprotuberances were slender.(2) The distribution characteristics of different molecularmarkers of DC in MLN: CD103+DC were mainly distributed the paracortical areasand the surrounding of the trabecular as well as distributed extensively in the medulla,but distributed relatively less in the germinal center. The cell morphology of theCD103+DC in different parts was similar, but the protuberance was not obvious;CD11c+DC were mainly distributed in germinal center、the paracortical areas and thesurrounding of the trabecular. These cells that the cell nucleus was large, slightly stained and the protuberance was long and thin, were surrounded by the surroundinglymphocytes; Almost all of the FDC-SP+DC were distributed in the folliculargerminal center. The FDC-SP+DC that the nuclear was irregular and the protuberancewas long and thin, was surrounded by B lymphocytes.(3) The distributioncharacteristics of CD68+Mφ in the small intestine MALT:Both the Mucous membraneand submucosa had the distribution of CD68+Mφ, what’s more, they were mainlydistributed in submucosa and the surrounding of the intestinal glands close tomuscularis mucos（athe surrounding of the intestinal glands located in deep layer）, butdistributed rarely in the intestinal villus. CD68+Mφ distributed in the intestinal villuswere round, large and had abundant cytoplasm, but the CD68+Mφ distributed in thesurrounding of the intestinal glands close to muscularis mucosa were longspindle-shaped and small.(4) The distribution characteristics of CD68+Mφ in MLN:CD68+Mφ was mainly distributed near the postcapillary venule and medullalymphatic sinus and the cell body with the kidney-shaped nuclei was big and hadabundant cytoplasm. To sum up, in the intestinal mucosa, both of CD103+DC andCD11c+DC were distributed in the immune induction zone PPs, but the former weredistributed more widely and the ability of the CD103+DC in uptaking and transportingthe antigen were stronger than the CD11c+DC; CD68+Mφ was mainly distributed inthe surrounding of the intestinal glands located in deep layer and submucosa. Becausethe CD68+Mφ located here accepted the antigen stimulation weakly in the healthcondition, the shape was small. The CD68+Mφ distributed in the intestinal villus wasoften in the active state so the shape was big. In the MLN, both the bone marrowdependent area and the thymus dependent area had the distribution of the CD11c+DCand it probably prompted the CD11c+DC presenting the antigens to both the T cellsand B cells. CD103+DC were mainly distributed in the T-dependent area and themedulla of MLN. The phenomenon probably showed that CD103+DC mainlypresented the antigens to the T cells. In addition, the CD103+DC distributed in the intestinal mucosa and MLN were probably in the different mature state. CD68+Mφwas mainly distributed in the postcapillary venule and medullary sinus and itindicated CD68+Mφ could timely monitor and devour the pathogenic microorganismfrom the blood and lymphatic fluid to T cells. Almost all the FDC+DC weredistributed in the follicular germinal center of the intestinal mucosa and MLN,participating in the production of memory B cells, antibody affinity maturation andthe maintain of humoral immunity.