Immunohistochemical investigation of the upper, lower and nictitating membrane of Elanus caeruleus
Immunohistochemical study to the upper and lower eyelids revealed that the CD1a-positive Langerhans cells of skin are distributed in the stratum basal more than the stratum spinosum of the squamous epithelium. As well as, it appears in the stroma around the blood vessels, HEV and around and inside the feather follicle. Moreover, no Langerhans cells were observed near the conjunctiva surface.
In addition, there is a varying concentration and un-equal distribution of lymphocytes within the CALT. Where, the B cells which cluster under the basement membrane were higher number than T cells which scattered close to blood vessels. While, the plasma cells were the fewest and randomly distributed within the CALT and it increase around HEV.
In the third eyelid, population of CD20+(B cell), CD3+(T cell) and CD1a+ (Langerhans cells) increase in density around the blood vessels, where the highest concentration was to T cells, while, the lowest population of the plasma cells diffuse as singular cells between the two surface of the membrane.