Partially HLA-matched multi-virus-specific polyclonal CD4+ and CD8+ cells with or without ex vivo expansion have shown promise in treating active infections in patients with post-solid organ transplantation or HSCT or with other immunosuppressed states but have only been described in a small number of cases.20,55, , –58 Papadopoulou et al.20 reported eleven patients of which eight patients had up to four active infections, with a virological and clinical response in 94%. Here, CD4 is linked to infection.