ANTIGEN-PRESENTING CAPACITY OF LANGERHANS CELLS FROM RAT ORAL EPITHELIUM

The ability of Langerhans cells (LC) From rat oral mucosa to internali ze and process antigens and to participate in the induction of T cell mitogenesis was examined. To purify LC from epithelial cells, monoclon al anti-class II antibodies and immunomagnetic beads were employed. Su spensions of epithelial cells, containing LC, were found to be effecti ve in mediating a Con A-induced T cell proliferation. Depletion of cla ss II molecule-expressing LC reduced the proliferation of T cells by 8 0%. Presentation of ovalbumin (OA) to primed T cells was found to be d ependent on the concentration of OA and the number of LC. Partially pu rified LC were five times as effective in inducing proliferation of pr imed T cells as the untreated suspension of epithelial cells. The data suggest that LC obtained from rat oral mucosa can generate accessory signals, process antigens and serve as antigen-presenting cells.