Acoustofluidic system for targeted antibody removal in transplantation: Enabling small-volume therapeutic apheresis.

Antibody-mediated rejection is a leading cause of allograft failure and mortality in pediatric solid organ transplant recipients. Current apheresis systems require large blood volumes and are primarily designed for adults, making them unsuitable for children and small animals. These systems often indiscriminately remove both harmful and protective antibodies, increasing the risk of complications such as life-threatening infections. To address this critical need, we developed acoustofluidic-based system for targeted antibody removal in transplantation (A-START). A-START is engineered to handle small blood volumes and has demonstrated efficacy in preclinical small animal trials. In a sensitized rodent skin transplantation model, A-START only demands 240 microliters of blood, selectively removing donor-specific alloantibodies (DSAs) while preserving protective antibodies, such as tetanus antibodies. A-START retains ~95% of beneficial antibodies and achieves a 60% improvement in DSA removal compared to conventional methods. These findings highlight the transformative potential of A-START as a promising, reliable, scalable solution for improving outcomes in pediatric transplantation and treating antibody-mediated diseases.