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

Purpose of review: 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.

Recent findings: 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.

Summary: 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.