Antigen presentation by renal tubular epithelial cells.

The interaction between immune effector cells such as T lymphocytes and parenchymal cells in organ-specific immune injury is dynamic. It is now appreciated that the specificity, intensity, and eventual destructive effects of such interactions can be greatly influenced by responses of the target issue. Renal tubular cells are particularly well suited to participate in such immune collaborations. (1) They are exposed to innumerable potentially immunogenic peptides from blood and glomerular filtrate and have pathways to further process these peptides; (2) they express surface molecules which facilitate their engagement to T cells; and (3) they can produce proinflammatory cytokines. In the models of immune-mediated tubulointerstitial injury that are currently studied, there has been a great interest in defining the T lymphocytes that initiate, accelerate, or suppress disease. Surprisingly, there has been relatively little attention on defining the tubular cell responses that regulate these immune-mediated processes. This review will therefore focus on this intriguing aspect of immune tubular injury and relate what is known about antigen presentation by tubular cells in autoimmune renal disease.