Natural anticoagulant and fibrinolytic pathways in renal allograft failure.

This is an immunocytochemical study of the relationship between depletion of natural anticoagulant and fibrinolytic pathways and allograft survival following renal transplantation. Patients (n = 44) were classified in three groups according to the length of time between transplantation and allograft failure: group 1 (n = 14) failed within a month of transplantation; group 2 (n = 14) failed between one month and one year after transplantation; and group 3 (n = 16) failed after one year of transplantation. Control biopsies were from donor kidneys (n = 16) prior to transplantation. There were no statistically significant differences in recipient age, gender, donor kidney type (living-related versus cadaver), histocompatibility, and plasma cholesterol, triglycerides, or creatinine concentrations between groups. However, group 1 allografts had a greater depletion of the vascular heparan sulfate proteoglycan-antithrombin III natural anticoagulant pathway than allografts in group 2 or 3 (P < or = 0.05), and this depletion was associated with significantly greater fibrin deposition in group 1 than in either group 2 or 3 (P < or = 0.05). All three groups demonstrated severe depletion of tissue plasminogen activator from arteriolar smooth muscle cells and depressed fibrinolysis as evidenced by increased fibrin/plasmin ratios. However, no significant differences were found for either endothelial thrombomodulin or T cell, neutrophil, or macrophage infiltration between the groups. These data indicate that differences in graft outcome may be determined more by compromised vascular function than by the presence of cellular infiltrates.