The Impact of Basiliximab on Clinical Treg Detection through the Interference with CD25 Binding Site

Objective. Basiliximab (BXM) is commercial monoclonal antibody inhibitor of interleukin 2 receptor, which is widely used in the transplantation therapy for preventing acute rejection. However, we found BXM would interfere with the detection of Treg through flow cytometry in clinical practice. This study aimed to explore the interference caused by BXM in the clinical detection of Treg. Methods. We compared the effects of BXM on two CD25 antibodies with different clone site, which are commonly used for Treg measurement. Results. The result suggested CD25 (2A3) was inhibited by BXM, while CD25 (M -A251) was not affected. Moreover, we found 2A3/M-A251 Treg Ratio could reflect Treg cell activity and BXM blood concentration to some extent. Conclusion. BXM can effectively inhibit the binding of CD25 (2A3) antibody to its receptor on T cells membrane, which should be noted during Treg clinical detection.