CD45RA-depleted DLI for the Treatment of Refractory/Persistent Viral Infections After Haploidentical Transplantation

Inclusion Criteria: Participants must meet all of the following criteria: * Patients who have undergone hematopoietic stem cell transplantation. * Presence of viremia and/or viral infection-related disease caused by a single virus or multiple viruses among the following: CMV, EBV, ADV, BK, B19, JC, HHV-6B, HSV1, or HSV2. * Patients who, after ≥2 weeks of first-line therapy, have persistent viral positivity, no relief or worsening of clinical symptoms, or re-infection with the same pathogen after viral clearance. * Availability of a suitable lymphocyte donor. * Adequate organ function, meeting the following laboratory criteria: * Liver function: ALT and AST ≤ 10 × upper limit of normal (ULN), TBIL ≤ 5 × ULN. * Renal function: BUN and Cr ≤ 1.25 × ULN. * No cardiac insufficiency on electrocardiogram (ECG) or echocardiogram. * Pulmonary function: oxygen saturation \> 90% on room air. * Willingness and ability of the patient or their legal guardian to receive treatment, comply with the treatment plan, follow-up schedule, and laboratory examinations, and provision of signed informed consent before any study-specific procedure. Exclusion Criteria: Patients meeting any of the following criteria will be excluded from this study: * Active grade II-IV acute graft-versus-host disease (aGVHD). * Prednisone or equivalent corticosteroid dose \> 0.5 mg/kg/day. * Receipt of anti-thymocyte globulin (ATG), alemtuzumab (Campath), or other T-cell immunosuppressive monoclonal antibodies withi…