Relationship between Serum Soluble Interleukin-2 Receptor and Renal Allograft Rejection: A Hospital-Based Study in Kashmir Valley

Abstract

Background: Even after adequate immunosuppression therapy, acute rejection continues to be the single most important cause of graft dysfunction after renal transplantation. Renal allograft biopsy continues to be the reference standard, though certain clinical and biochemical parameters are helpful in assessment of these patients. Renal allograft rejection is mediated by T lymphocytes, expressing cell surface interleukin-2 receptors (IL-2R) which has been suggested as a marker of acute rejection episodes after organ transplantation.

Objective: To determine the pre- and post-transplantation serum soluble IL-2R levels in live related kidney transplant patients to predict acute rejection episodes.

Methods: Serial serum samples from 75 recipients and 41 healthy controls were assessed for soluble IL- 2R levels by ELISA. The outcome of the graft was also determined for each recipient.

Results: The mean±SD serum soluble IL-2R levels in renal allograft recipients with rejection were significantly (p<0.001) higher than those without rejection (329.85±59.22 vs 18.12±11.22 pg/mL). The elevation of serum soluble IL-2R was evident in acute rejection episodes and found before elevation of serum creatinine. The higher values of serum soluble IL-2R in the rejection group were significantly reduced after recovery of allograft function by adequate anti-rejection therapy. 36.4% of patients in the rejection group had proven positive biopsies for the rejection and higher creatinine values, which was found to be statistically significant (p<0.001). A cohort of 41 healthy controls showed significantly (p<0.05) lower serum soluble IL-2R concentrations (15.27±7.79 pg/mL) when compared with the rejection group.

Conclusion: Serum soluble IL-2R concentrations showed significant correlation with the acute rejection episodes in the renal allograft recipients. Prediction of soluble IL-2R levels might help the early detection of rejection episodes, which may pave way for the management of immunosuppression regimes and better graft functioning.