In this episode, Marco Davila and Brian Betts explain that taking advantage of the differential expression of CD83, human CD83-targeted CAR T cells prevent and treat GVHD, as well as kill myeloid leukemia.
Graft-versus-host disease (GVHD) remains an important cause of morbidity and mortality after allogeneic hematopoietic cell transplantation (allo-HCT). For decades, GVHD prophylaxis has included calcineurin inhibitors, despite their incomplete efficacy and impairment of graft-versus-leukemia (GVL). Distinct from pharmacologic immune suppression, we have developed what we believe is a novel, human CD83-targeted chimeric antigen receptor (CAR) T cell for GVHD prevention. CD83 is expressed on allo-activated conventional CD4+ T cells (Tconvs) and proinflammatory dendritic cells (DCs), which are both implicated in GVHD pathogenesis. Human CD83 CAR T cells eradicate pathogenic CD83+ target cells, substantially increase the ratio of regulatory T cells (Tregs) to allo-activated Tconvs, and provide durable prevention of xenogeneic GVHD. CD83 CAR T cells are also capable of treating xenogeneic GVHD. We show that human acute myeloid leukemia (AML) expresses CD83 and that myeloid leukemia cell lines are readily killed by CD83 CAR T cells. Human CD83 CAR T cells are a promising cell-based approach to preventing 2 critical complications of allo-HCT — GVHD and relapse. Thus, the use of human CD83 CAR T cells for GVHD prevention and treatment, as well as for targeting CD83+ AML, warrants clinical investigation.
Bishwas Shrestha, Kelly Walton, Jordan Reff, Elizabeth M. Sagatys, Nhan Tu, Justin Boucher, Gongbo Li, Tayyebb Ghafoor, Martin Felices, Jeffrey S. Miller, Joseph Pidala, Bruce R. Blazar, Claudio Anasetti, Brian C. Betts, Marco L. Davila