Antiviral T Cells for Adenovirus in the Pretransplant Period: A Bridge Therapy for Severe Combined Immunodeficiency

Viral infections can be life threatening in patients with severe combined immunodeficiency (SCID) and other forms of profound primary immunodeficiency disorders both before and after hematopoietic stem cell transplantation (HSCT). Adoptive immunotherapy with virus-specific T cells (VSTs) has been utilized in many patients in the setting of HSCT, but has very rarely been attempted for treatment of viral infections before HSCT. Here we describe the use of VSTs in an infant with RAG1 SCID who had developed disseminated adenovirus which failed to improve on cidofovir. Adenovirus cleared following 2 doses of VSTs and marrow infusion from a matched unrelated donor, without incidence of graft versus host disease. T cell receptor-b sequencing demonstrated expansion of adenovirus-specific T cell fraction of the VSTs, suggesting that infusion facilitated viral clearance. This report suggests that VSTs are likely safe in the pre-HSCT period, and may be a useful bridge therapy for infants with SCID and persistent viral infections.