Serum soluble interleukin 2 receptor (sIL-2R) as a marker of acute rejection in renal transplant children

The aim of the study was to evaluate whether or not serum levels of soluble interleukin 2 receptor (sIL-2R) predict acute rejection in pediatric recipients. We studied 51 pediatric renal transplant recipients divided into three groups: Group 1) Biopsy-proven cellular acute rejection (n = 19), Group 2) Graft dysfunction with histological diagnosis other than acute rejection (n = 8) and Group 3) Patients with stable graft function, no biopsy (n = 24). Serum samples for sIL-2R measurement by sandwich ELISA were obtained at the time of renal transplant and at the time of renal biopsy due to graft dysfunction (Groups 1 and 2) or at six months post-transplant in the case of Group 3. The mean ± s.e. serum values of sIL-2R were higher in patients during acute rejection (6539 ± 1802 pg/mL) compared to patients with other causes of graft dysfunction (2217 ± 256 pg/mL) or stable graft function at six months (2183 ± 283 pg/mL) (Kruskal-Wallis p = 0.004). When the sIL2-R levels at the time of transplant were compared to those at the time of biopsy (Groups 1 and 2) or at six months post-transplant in Group 3, there was no significant difference between baseline and biopsy in the acute rejection group (paired t-test = 0.07), whereas there was a significant reduction in Groups 2 and 3.