Cellular Therapies in Transplantation - Regulatory T Cell Therapies and Virus Specific Therapies

Cellular therapies have shown great promise in enhancing immune tolerance and managing opportunistic infections in transplant recipients. This review explores the latest advancements in regulatory T cell (Treg) and virus-specific T cell (VST) therapies in solid organ transplantation.

Treg-based therapies, including polyclonal Tregs, donor antigen-reactive Tregs (darTregs), and chimeric antigen receptor Tregs (CAR-Tregs) are being studied to minimize conventional, systemic immunosuppression while preventing graft rejection. Clinical trials demonstrated the safety and feasibility of ex vivo-expanded Tregs in kidney and liver transplantation, supporting reduced rejection rates and lower infection risks. The clinical applicability of CAR-T cell therapies extends to autoimmune diseases. Additionally, VSTs targeting BK virus, cytomegalovirus, Epstein-Barr virus, and adenovirus offer a novel approach for refractory viral infections in transplant recipients. Advances in third-party, "off-the-shelf" and multi-VSTs allow faster availability and standardized, scalable manufacturing compared to conventional VSTs.

By reducing dependence on conventional immunosuppression, cellular therapies provide a promising approach in transplantation. To establish their role in clinical transplantation, further research is needed to optimize dosing and manufacture, improve antigen specificity, and address long-term safety concerns.