MUCOSA SPECIFIC LYMPHOCYTES IN THE HUMAN CONJUNCTIVA, CORNEOSCLERAL LIMBUS AND LACRIMAL GLAND

Conjunctiva associated lymphoid tissue shows several similarities to m ucosa associated lymphoid tissue of the gut and respiratory tract. The se similarities have been described in relation to lymphocyte subpopul ations and epithelial cell morphology. However, unlike the lymphoid ti ssue of the gut and respiratory tract, mucosa specific lymphocytes hav e not been described in the ocular mucosa. In this study we demonstrat ed the presence of mucosa specific lymphocytes bearing the Human Mucos al Lymphocyte - 1 antigen (beta 7 integrin), in the human conjunctiva, limbus and lacrimal gland. The distribution of this subset of lymphoc ytes corresponded to the distribution of CD8+ T-cells and was found ma ximally in the epithelium of the epibulbar conjunctiva and in the lacr imal gland. The Human mucosal lymphocyte antigen may function to deter mine mucosal homing of this particular subset of CD8+ T-cells, which i n turn, may have special function in immunological defense and toleran ce mechanisms occurring at mucosal surfaces.