Cellular Evidence of Telocytes as Novel Interstitial Cells within the Magnum of Chicken Oviduct

Abstract Telocytes are a novel type of interstitial cells recently identified in many organs of mammals, but little information in the avian. So this study shows the latest findings associated with telocytes, with a special attention on the magnum of chicken oviduct, in the muscular layer and lamina propria by transmission electron microscopy. Telocytes are characterized by telopodes, which are thin and long prolongations, and a small amount of cytoplasm rich with mitochondria. Different shaped telocytes (spindle to triangular) depending on the number of prolongations. In the muscular layer, telocytes have direct connection with smooth muscle cells, the cell body of telocytes mainly exist in the interstitial space between the smooth muscle bundles and their telopodes is very long, whereas, large number of short telopodes were scattered in between the smooth muscle cells except the cell body of telocytes. In the lamina propria, extremely long telopodes were twisting around each other and were usually collagen-embedded. Both in the lamina propria and muscular layer, telocytes have a close relationship with other cell types, such as immune cells and never ending and blood vessels. Telopodes appear with dichotomous branching and alternation of podom and podomer, forming a 3D network structure with complex homo- and hetero-cellular junctions. In addition, distinctive size of vesicles were visible around the telopodes, and maybe released from telopodes because the close relation between vesicle and telopode. All characteristics of telocytes in the magnum indicate that telocytes may play a potential, but important, role in the pathogenesis of oviduct diseases.