[Age-dependent distribution of Langerhans cells within human conjunctival epithelium]

Non-pathological conjunctival specimens (240) were used for evaluation of Langerhans cell (LC) numbers per square millimeter. Of the 240, 60 were taken from each of four age groups (1-20 years, 21-40 years, 41-60 years, 61 years and older). In each group, 20 came from the bulbar conjunctiva (lateral superior), 20 from the fornix region (central superior), and 20 from the palpebral conjunctiva (central inferior). Quantitative analysis was carried out with the Langerhans-specific anti-CD1a antibody using APAAP method. Additionally, 40 conjunctival specimens were stained with the Tü 36 (all HLA/DR Ag) and the Tü 39 (all HLA/DR, -/DP Ag). A basic decline in the density of LC cells corresponding to advancing age of the tissue donors was found in all three regions studied (< or = 20 years: 4.4 LC/mm2; > 60 years: 1.2 LC/mm2). The largest number of LC (4.7 LC/mm2) was found in the palpebral conjunctiva (central inferior); 3.1 LC/mm2 were found in the fornix (central superior) and 1.0 LC/mm2 in the bulbar conjunctiva (lateral superior). As an antigen-presenting cell, the LC plays an important role in immune reactions in the area of the superficial ocular epithelium. The data gained here can serve as a basis for studies of pathological tissue since, as is known from dermatological research, firm relationships exist between specific inflammatory or tumorous diseases and LC density in the affected organs. Moreover, a direct connection is to be assumed between the success of transplantation and LC density in allogenic conjunctival grafts.