T cells bearing anti-CD19 and/or anti-CD38 chimeric antigen receptors effectively abrogate primary double-hit lymphoma cells

Patients with B cell lymphomas bearing MYC translocation combined with translocation involving other genes, such as BCL2, BCL3, or BCL6, defined as double-hit lymphoma (DHL), have a poor prognosis. Recent studies expanded the concept to include double-expressing lymphoma (DEL) that co-overexpresses MYC protein with either of those proteins. Accordingly, we defined cytogenetic DHL and DEL as primary DHL. An adoptive T cell immunotherapy with a chimeric antigen receptor (CAR) has been clinically shown to exhibit cytotoxicity in refractory neoplasias. We revealed the marked cytotoxicity of anti-CD19- and/or anti-CD38-CAR T cells against primary DHL cells from patients. CD19- and/or CD38-specific T cells were co-cultured with cytogenetic DHL (n = 3) or DEL (n = 2) cells from five patients for 3 days. We examined whether T cells retrovirally transduced with each vector showed cytotoxicity against DHL cells. Anti-CD19- and/or anti-CD38-CAR T cells were co-cultured with primary DHL cells at an E:T ratio of 1:2 for 3 days. Anti-CD19- and anti-CD38-CAR T cells completely abrogated these DHL cells, respectively. Anti-CD19-CAR T cells synergistically exerted collaborative cytotoxicity against these primary DHL cells with anti-CD38-CAR T cells. Therefore, refractory DHL cells can be efficiently abrogated by the clinical use of T cells with anti-CD19- and/or anti-CD38-CAR.