Analysis of the feasibility and prognostic value of circulating tumor DNA monitoring in detecting gene mutations in patients with diffuse large B-cell lymphoma receiving chimeric antigen receptor T-cell therapy / 中华血液学杂志

Objective: To explore the prognostic value of circulating tumor DNA (ctDNA) testing in patients with refractory/relapsed diffuse large B-cell lymphoma (R/R DLBCL) undergoing chimeric antigen receptor T-cell (CAR-T) therapy, and to guide the prevention and subsequent treatment of CAR-T-cell therapy failure. Methods: In this study, 48 patients with R/R DLBCL who received CAR-T-cell therapy at the First Affiliated Hospital of Zhejiang University School of Medicine between December 2017 and March 2022 were included. Furthermore, ctDNA testing of 187 lymphoma-related gene sets was performed on peripheral blood samples obtained before treatment. The patients were divided into complete remission and noncomplete remission groups. The chi-square test and t-test were used to compare group differences, and the Log-rank test was used to compare the differences in survival. Results: Among the patients who did not achieve complete remission after CAR-T-cell therapy for R/R DLBCL, the top ten genes with the highest mutation frequencies were TP53 (41%), TTN (36%), BCR (27%), KMT2D (27%), IGLL5 (23%), KMT2C (23%), MYD88 (23%), BTG2 (18%), MUC16 (18%), and SGK1 (18%). Kaplan-Meier survival analysis revealed that patients with ctDNA mutation genes >10 had poorer overall survival (OS) rate (1-year OS rate: 0 vs 73.8%, P<0.001) and progression-free survival (PFS) rate (1-year PFS rate: 0 vs 51.8%, P=0.011) compared with patients with ctDNA mutation genes ≤10. Moreover, patients with MUC16 mutation positivity before treatment had better OS (2-year OS rate: 56.8% vs 26.7%, P=0.046), whereas patients with BTG2 mutation positivity had poorer OS (1-year OS rate: 0 vs 72.5%, P=0.005) . Conclusion: ctDNA detection can serve as a tool for evaluating the efficacy of CAR-T-cell therapy in patients with R/R DLBCL. The pretreatment gene mutation burden, mutations in MUC16 and BTG2 have potential prognostic value.

Weathering the storm: COVID-19 infection in patients with hematological malignancies / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Within a matter of months, this highly contagious novel virus has led to a global outbreak and is still spreading rapidly across continents. In patients with COVID-19, underlying chronic diseases and comorbidities are associated with dismal treatment outcomes. Owing to their immunosuppressive status, patients with hematological malignancies (HMs) are at an increased risk of infection and have a worse prognosis than patients without HMs. Accordingly, intensive attention should be paid to this cohort. In this review, we summarize and analyze specific clinical manifestations for patients with coexisting COVID-19 and HMs. Furthermore, we briefly describe customized management strategies and interventions for this susceptible cohort. This review is intended to guide clinical practice.

Current advances in chimeric antigen receptor T-cell therapy for refractory/relapsed multiple myeloma / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Multiple myeloma (MM), considered an incurable hematological malignancy, is characterized by its clonal evolution of malignant plasma cells. Although the application of autologous stem cell transplantation (ASCT) and the introduction of novel agents such as immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs) have doubled the median overall survival to eight years, relapsed and refractory diseases are still frequent events in the course of MM. To achieve a durable and deep remission, immunotherapy modalities have been developed for relapsed/refractory multiple myeloma (RRMM). Among these approaches, chimeric antigen receptor (CAR) T-cell therapy is the most promising star, based on the results of previous success in B-cell neoplasms. In this immunotherapy, autologous T cells are engineered to express an artificial receptor which targets a tumor-associated antigen and initiates the T-cell killing procedure. Tisagenlecleucel and Axicabtagene, targeting the CD19 antigen, are the two pacesetters of CAR T-cell products. They were approved by the US Food and Drug Administration (FDA) in 2017 for the treatment of acute lymphocytic leukemia (ALL) and diffuse large B-cell lymphoma (DLBCL). Their development enabled unparalleled efficacy in combating hematopoietic neoplasms. In this review article, we summarize six promising candidate antigens in MM that can be targeted by CARs and discuss some noteworthy studies of the safety profile of current CAR T-cell therapy.

Anti-cD20scFv/CD80/CD28/zeta specific T lymphocytes eradicate primary chronic lymphocytic leukemia cells in vitro / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To construct anti-CD20scFv/CD80/CD28/zeta recombinant gene modified T cells, test its effectiveness of eradicating CD20 positive primary chronic lymphocytic leukemia (CLL) cells and provide a promising tool for tumor adoptive immunotherapy.</p><p><b>METHODS</b>The recombinant vectors were transduced into PA 317 cells and high titer retroviruses were obtained to infect human peripheral blood T lymphocytes. Resistant T cells were obtained by G418 selection for one week. Then transduced T lymphocytes and primary CLL cells were co-cultured. The status of primary chronic lymphocytic leukemia cells were observed by microscope. The level of IL-2 and IFN-gamma in the culture medium were measured.</p><p><b>RESULTS</b>Primary T cells expressing anti-CD20scFv/IgGFc/CD80/CD28/zeta could be constructed successfully. These T cells were able to lyse CD20+ targets and secrete high levels of IL-2 (1301.00 pg/ml) and IFN-gamma (602.18 pg/ml) in vitro.</p><p><b>CONCLUSION</b>(1) Recombinant gene modified T cells can be constructed successfully. (2) Recombinant gene modified T cells can specially kill CD20 positive primary CLL cells in vitro.</p>

Construction of recombinant retroviruses expressing anti-CD20 scFv/CD80 /CD28/zeta gene and expression in Jurkat cell line / 中国应用生理学杂志

<p><b>AIM</b>To construct recombinant retroviruses expressing anti-CD20 scFv/CD80/CD28/zeta gene and detect its expression in Jurkat cells.</p><p><b>METHOD</b>CD28-zetacDNA were amplified from plasmids pBULLET and inserted into pLNCX vector that contained anti-CD20 scFv/CD80 gene. The recombinant plasmids were transfected into PA 317 cells. Retroviruses were harvested from culture medium of PA 317 cells. Then NIH 3T3 were transfected with retroviruses. Objective gene expression was determined by PCR and FACS. Jurkat cells were transfected with high titer of retroviruses and resistant clones were obtained by G418 selection. Objective mRNA was determined by RT- PCR.</p><p><b>RESULTS</b>The recombinant eukaryotic vector was constructed successfully by PCR and enzyme digestion analysis and objective gene was amplified from NIH 3T3 cells transfected with retroviruses by PCR; FACS showed that objective protein could be expressed in NIH 3T3 cells. Objective gene was amplified from Jurkat cells transfected with retroviruses by RT-PCR.</p><p><b>CONCLUSION</b>Recombinant retrovirus expressing anti-CD20 scFv/CD80/CD28/zeta gene was successfully constructed and objective protein could be expressed in Jurkat cells.</p>

Construction of anti-cD20scFv/CD80/CD28/zeta recombinant gene modified T cell and research on its targeting cytotoxicity / 中华血液学杂志

<p><b>OBJECTIVE</b>To construct anti-CD20scFv/CD80/CD28/zeta recombinant gene modified T cells, test its effectiveness of eradicating CD20+ lymphoma cells and provide a probably new approach to tumor adoptive immunotherapy.</p><p><b>METHODS</b>CD28-zeta cDNA were amplified from vector pBULLET and inserted into pLNCX vector that contained anti-CD20scFv/CD80 gene. The recombinant vectors were transduced into PA317 cells and high titer retroviruses were obtained to infect human peripheral blood T lymphocytes. Resistant T cells were obtained by G418 selection at one week. Then transduced T lymphocytes and lymphoma cell lines Daudi Raji were cocultured. The cytotoxicity and cytokine production of transduced T cells were determined by non-radio-activation cytotoxicity assay and ELISA respectively.</p><p><b>RESULTS</b>The recombinant eukaryotic vector was constructed successfully as proved by enzyme digestion analysis and sequencing. These T cells were able to lyse CD20+ target cells and secrete high levels of IL-2 and IFN-gamma in vitro.</p><p><b>CONCLUSION</b>Recombinant gene modified T cells can be constructed successfully. It can specially kill CD20 positive lymphoma cells in vitro.</p>