Two-stage CD8+ CAR T-cell differentiation in patients with large B-cell lymphoma
Guoshuai Cao, Yifei Hu, Tony Pan, Erting Tang, Nicholas Asby, Thomas Althaus, Jun Wan, Peter A. Riedell, Michael R. Bishop, Justin Kline, Jun Huang
Abstract
Advancements in chimeric antigen receptor (CAR) T-cell therapy for treating diffuse large B-cell lymphoma (DLBCL) have been limited by an incomplete understanding of CAR T-cell differentiation in patients. Here, we show via single-cell, multi-modal, and longitudinal analyses, that CD8+ CAR T cells from DLBCL patients successfully treated with axicabtagene ciloleucel undergo two distinct waves of clonal expansion in vivo. The first wave is dominated by an exhausted-like effector memory phenotype during peak expansion (day 8–14). The second wave is dominated by a terminal effector phenotype during the post-peak persistence period (day 21–28). Importantly, the two waves have distinct ontogeny from the infusion product and are biologically uncoupled. Precursors of the first wave exhibit more effector-like signatures, whereas precursors of the second wave exhibit more stem-like signatures. We demonstrate that CAR T-cell expansion and persistence are mediated by clonally, phenotypically, and ontogenically distinct CAR T-cell populations that serve complementary clinical purposes. Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease group with CAR T cells offering therapeutic success in otherwise hard-to-treat cases. Here, authors study the in vivo expansion and persistence of CAR T cells in the peripheral blood of successfully treated DLBCL patients, demonstrating that two different CD8+ precursor phenotypes in the initial cell product give rise to two independent waves of clonally expanded CAR T cells with distinct phenotypes in peripheral blood.