Toll-like receptors (TLR) comprise an emerging family that recognize pathogen-associated molecular patterns and promote the activation of leukocytes. Recently, TLR has been demonstrated to play a role in experimental allograft rejection. However, the TLR-4 gene has a polymorphism that can be associated with a blunted immune response, especially to microbial pathogens. We sought to study the incidence of TLR 4 gene variants among renal transplant donors and recipients from living and deceased organs and then to correlate them with short-term and long-term outcomes.
Methods: Analysis of TLR4 polymorphisms at Asp299Gly and Thr399Ile codons were performed using restriction fragment length polymorphism. Demographic data was obtained from patient records.
Results: Among 201 patients, 141 were recipients from related donors (group 1) and 60 recipients from 45 deceased donors (group 2). Patients were followed for 108 +/- 85 months after transplantation. The incidence of polymorphism for TLR-4 Asp299Gly, Thr399Ile or both were 8.9% in recipients and 8.0% in donors. Patients who received a kidney with polymorphism, Asp299Gly, or Thr399Ile, or both, did not show a difference in rate of acute tubular necrosis compared with controls (no polymorphism). Acute rejection occurred in 17.6% of recipients with Asp299Gly/Thr399Ile polymorphisms and in 39.5% of wild-type recipients (P = .400). The incidence of bacterial infection was equal in both groups.
Conclusion: The incidence of polymorphism in this study was similar in both groups, and donor or recipient polymorphisms were not associated with different renal graft outcomes.