ABSTRACT
Anti-CD19 chimeric antigen receptor (CAR)-T cell therapy has achieved 40%-50% long-term complete response in relapsed or refractory diffuse large B-cell lymphoma (DLBCL) patients. However, the underlying mechanism of alterations in the tumor microenvironments resulting in CAR-T cell therapy failure needs further investigation. A multi-center phase I/II trial of anti-CD19 CD28z CAR-T (FKC876, ChiCTR1800019661) was conducted. Among 22 evaluable DLBCL patients, seven achieved complete remission, 10 experienced partial remissions, while four had stable disease by day 29. Single-cell RNA sequencing results were obtained from core needle biopsy tumor samples collected from long-term complete remission and early-progressed patients, and compared at different stages of treatment. M2-subtype macrophages were significantly involved in both in vivo and in vitro anti-tumor functions of CAR-T cells, leading to CAR-T cell therapy failure and disease progression in DLBCL. Immunosuppressive tumor microenvironments persisted before CAR-T cell therapy, during both cell expansion and disease progression, which could not be altered by infiltrating CAR-T cells. Aberrant metabolism profile of M2-subtype macrophages and those of dysfunctional T cells also contributed to the immunosuppressive tumor microenvironments. Thus, our findings provided a clinical rationale for targeting tumor microenvironments and reprogramming immune cell metabolism as effective therapeutic strategies to prevent lymphoma relapse in future designs of CAR-T cell therapy.
ABSTRACT
Factors associated with complete and durable remissions after anti-CD19 chimeric antigen receptor T (CAR-T) cell immunotherapy for relapsed or refractory non-Hodgkin lymphoma (r/r NHL) have not been well characterized. In this study, we found that the different sites of extranodal involvement may affect response, overall survival (OS), and progression-free survival (PFS) in patients with r/r NHL treated with anti-CD19 CAR-T cells. In a cohort of 32 treated patients, 12 (37.5%) and 8 (25%) patients exhibited soft tissue lymphoma and bone marrow (BM) infiltrations, respectively, and 13 (41%) patients exhibited infiltration at other sites. The factors that may affect prognosis were identified through multivariable analysis. As an independent risk factor, soft tissue infiltration was the only factor significantly correlated with adverse prognosis (P < 0.05), whereas other factors did not reach statistical significance. Furthermore, the site of extranodal tumor infiltration significantly and negatively affected OS and PFS in patients with r/r NHL treated with anti-CD19 CAR-T cell therapy. PFS and OS in patients with BM involvement were not significantly different from those of patients with lymph node involvement alone. Thus, anti-CD19 CAR-T cell therapy may improve the prognosis of patients with BM infiltration.
Subject(s)
Humans , Cell- and Tissue-Based Therapy , Immunotherapy, Adoptive , Lymphoma, Non-Hodgkin/therapy , Receptors, Antigen, T-Cell , Receptors, Chimeric AntigenABSTRACT
Mantle cell lymphoma (MCL) is a distinct histological type of B-cell lymphoma with a poor prognosis. Several agents, such as proteasome inhibitors, immunomodulatory drugs, and inhibitors of B cell lymphoma-2 and Bruton's tyrosine kinase have shown efficacy for relapsed or refractory (r/r) MCL but often have short-term responses. Chimeric antigen receptor (CAR) T-cell therapy has emerged as a novel treatment modality for r/r non-Hodgkin's lymphoma. However, long-term safety and tolerability associated with CAR T-cell therapy are not defined well, especially in MCL. In this report, we described a 70-year-old patient with r/r MCL with 48-month duration of follow-up who achieved long-term remission after CAR T-cell therapy. CAR T-cell-related toxicities were also mild and tolerated well even in this elderly patient. This report suggested that CAR T-cell therapy is a promising treatment modality for patients with MCL, who are generally elderly and have comorbid conditions.
Subject(s)
Adult , Aged , Humans , Cell- and Tissue-Based Therapy , Immunotherapy, Adoptive , Lymphoma, Mantle-Cell/therapy , Neoplasm Recurrence, Local , Receptors, Chimeric AntigenABSTRACT
@#[Abstract] Objective: To establish a chimeric antigen receptor（CAR）modified T cells specifically targeting CD19 molecule (CD19CAR-T cells) and to testify their in vitro killing effect on target cells. Methods: CD19-CAR fragments yielded by PCR were constructed into pCDH-GFP lentiviral vectors by molecular cloning technology. The packaged lentiviral particles were transducted into CD3+ T cells of donors. Transduction efficiency was measured by flow cytometry and PCR. The in vitro cytotoxicity of obtained CD19CAR-T cells against CD19+ Ramos cells was tested by 7-AAD staining. Results: The amplification folds of CD3+ T cells increased to (78.8± 23.2) folds after in vitro culture for 10 days, and about (58.3±5.4)% cells expressing GFP.About (57.4±9.3)% CD19+Ramos cells were specifically killed by the CD19-CAR-T cells in vitro at the E∶T ratio of 5∶1. Conclusion: This study successfully established an effective method for constructing and amplifying CD19-CAR-T cells in vitro, which showed profound efficiency and specific cytotoxity against CD19+ Ramos cells.And this report might provide an experimental evidence for clinical treatment of CD19+ B cell neoplasmas.