Analysis of T cell lines from rejecting renal allografts.

Acute rejection after renal allotransplantation is characterized by the presence of a mononuclear cell infiltrate in the interstitium with involvement of tubuli. In a previous study on renal histology we showed that tubular damage by graft infiltrating cells (GIC) is a sign of clinically significant rejection. We cultured proximal tubular epithelial cells (PTEC) and T cells bearing the interleukin 2 (IL-2) receptor from biopsies after transplantation.

IL-1 alpha stimulated TNF alpha production by cultured human proximal tubular epithelial cells.

Tumor necrosis factor alpha (TNF alpha) production by proximal tubuli was studied by immunoperoxidase staining of 20 renal biopsies from transplant patients. A positive staining for TNF alpha on proximal tubuli was seen in nine out of 15 patients with interstitial infiltrate, five without clinical significant rejection and four with moderate to severe interstitial rejection. TNF alpha was only expressed on tubuli within areas of interstitial infiltrate.