BK With VST for Kidney Transplant Patients

Inclusion Criteria: * Age18 ≤ 75 years * Have BKV infection/viremia following kidney transplantation, where BKV viremia is defined as positive BKV qPCR (≥ 250 copies) * Have evidence of invasive BKV infection (BK Nephropathy) * Experience one of the following: * New, persistent and/or worsening BKV-related symptoms, signs and/or markers of end organ compromise despite being on lower immunosuppressive medication * Adverse effects of lower immunosuppressive medications (e.g., dnDSA, biopsy proven rejection) * Eligible Donor * Provide Written informed consent Exclusion Criteria: * Non-kidney organ transplant recipient * Patient with acute rejection of the kidney allograft at time of T-cell transfer * Patient receiving steroids (\>0.5 mg/kg body weight (BW) prednisone equivalent) at the time of T-cell transfer * Patient treated with Thymoglobulin (ATG), Alemtuzumab or T-cell immunosuppressive monoclonal antibodies within 28 days prior to T-cell transfer * Extra renal tissue invasive BK infection * Concomitant enrollment in another clinical trial interfering with endpoints of this study * Any medical condition which could compromise participation in the study according to the investigator's assessment * Known HIV infection * Female patient who is pregnant or breast-feeding, or adult of reproductive potential not willing to use an effective method of birth control during study treatment Note: Women of childbearing potential must have a negative urine pregnancy test at study…