CMV-CMI in csCMVi After HSCT

Cytomegalovirus (CMV) reactivation is a common and serious complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT), and the reconstitution of CMV-specific cell-mediated immunity (CMV-CMI) plays a key role in viral control. This prospective, exploratory study will enroll 40 adult CMV-seropositive patients who experience their first CMV reactivation after allo-HSCT. CMV-specific T cell levels (IFN-γ-producing T cells stimulated by IE-1 and pp65 antigens) will be measured using ELISPOT at four time points: at diagnosis of CMV viremia, 3 weeks after initiating preemptive therapy, at anti-CMV drug withdrawal, and 4 weeks after treatment discontinuation. Patients will be followed for 12 weeks after stopping treatment. The primary objective is to describe the changes in CMV-specific T cell levels over the therapy. Secondary objectives are to explore the relationship between these levels and the occurrence of refractory CMV infection, recurrent CMV infection, and CMV disease. Findings may help identify patients at high risk of progressing to severe or persistent CMV infection at an early stage of preemptive therapy, enabling personalized intervention strategies.