Induction of RANTES, HLA-DR, and intercellular adhesion molecule-1 on highly purified distal tubular cells from human kidney

(B)ackground Expression of proinflammatory molecules by tubular epithelial cells plays an important role in renal allograft rejection and inflammatory kidney diseases. Different studies from patients with acute rejection poin t to the involvement of distal tubular segments. At present no in vitro sys tem for the human distal tubule is established. Methods. Human distal tubular cells were isolated immunomagnetically. Cultu red cells were stimulated with cytokines (interferon-gamma, tumor necrosis factor-alpha, interleukin-1 beta, or a cytokine mix). Secretion of RANTES ( regulated upon activation, normal T-cell expressed and secreted) was evalua ted with an enzyme-linked immunoassay, Expression of HLA-DR and intercellul ar adhesion molecule (ICAM)-1 was assessed by flow cytometric analysis and immunofluorescence studies. Results. Our data clearly indicate that distal tubular cells express RANTES , HLA-DR, and ICAM-1 in response to a mixture of specific cytokines. Dexame thasone inhibited the induced expression of RANTES and HLA-DR significantly , but not that of ICAM-1. Conclusions. We demonstrate an appropriate in vitro system for the human di stal tubule. The present study proves the involvement of the distal tubular segment during inflammatory kidney diseases.