Soluble CD30 in patients with antibody-mediated rejection of the kidney allograft

The aim of our retrospective study was to evaluate the clinical significance of measurement of the soluble CD30 (sCD30) molecule for the prediction of antibody-mediated (humoral) rejection (HR). Sixty-two kidney transplant recipients (thirty-one C4d-positive and thirty-one C4d-negative patients) were included into the study. Soluble CD30 levels were evaluated before transplantation and during periods of graft function deterioration. The median concentrations of the sCD30 molecule were identical in C4d-positive and C4d-negative patients before and after transplantation (65.5 vs. 65.0 and 28.2 vs. 36.0 U/ml, respectively). C4d+ patients who developed DSA de novo had a tendency to have higher sCD30 levels before transplantation (80.7 ± 53.6 U/ml, n = 8) compared with C4d-negative patients (65.0 ± 33.4 U/ml, n = 15). Soluble CD30 levels were evaluated as positive and negative (≥ 100 U/ml and < 100 U/ml respectively) and the sensitivity, specificity and accuracy of sCD30 estimation with regard to finding C4d deposits in peritubular capillaries were determined. The sensitivity of sCD30+ testing was generally below 40%, while the specificity of the test, i.e. the likelihood that if sCD30 testing is negative, C4d deposits would be absent, was 82%. C4d+ patients who developed DSA de novo were evaluated separately; the specificity of sCD30 testing for the incidence of HR in this cohort was 86%.ConclusionWe could not confirm in our study that high sCD30 levels (≥ 100 U/ml) might be predictive for the incidence of HR. Negative sCD30 values might be however helpful for identifying patients with a low risk for development of DSA and antibody-mediated rejection.