Thymus of Rana perezi : Presence of interdigitating cells

In the thymus of Rana perezi , as in other anuran amphibians, there exist two different portions, cortex and medulla. In both sections epithelio‐reticular cells are observed as are lymphocytes, macrophages, and granulocytes. In addition, the medulla shows cysts and secretory, myoid, and hypertrophied epithelio‐reticular cells. In the cortex, plasma cells and interdigitating cells were also observed. Interdigitating cells make contact with lymphocytes. This finding provides morphological support for the hypothesized role of interdigitating cells in antigen presentation.