Relationship of cytokines to adverse reaction of chimeric antigen receptor T cell immunotherapy and targeted drug intervention / 中国生物制品学杂志

@#Chimeric antigen receptor T cell(CAR-T)immunotherapy is the most potential adoptive immunotherapy for malignant tumors,which needs no antigen presenting cells(APC)and is not limited by major histocompatibiliy complex(MHC). CAR-T immunotherapy not only recognizes and kills tumor cells directly,but also forms memory T cells and establishs long-term anti-tumor mechanism,of which the effect in leukemia,multiple myeloma and other non-solid tumors as well as the great potential in solid tumors have been widely verified. However,a variety of adverse reactions such as cytokine release syndrome(CRS),neurotoxicity(NT)and miss target effect are produced during CAR-T immunotherapy,of which the occurrence of CRS and NT may be related to the abnormal level of cytokines. Remarkable increase of cytokine level is a major characteristics of CRS. However,the increase of cytokines is neither the root cause nor the only result of CAR-T adverse reaction. CAR-T immunotherapy has a high incidence of adverse reaction which may even endanger the life of patients. Cytokine targeted drugs such as Anakinra and Tocilizumab may decrease the incidence of adverse reaction and improve the prognosis of patients. This paper reviews the correlation of cytokines with CRS and NT in CAR-T immunotherapy and the effect of cytokine targeting drugs,so as to provide a reference for the basic research,quality control and clinical application of CAR-T immunotherapy.

Preclinical study of suicide gene as a safety switch to control CAR-T cell cytotoxicity / 中国肿瘤生物治疗杂志

@#[Abstract] Objective: To investigate whether AP1903, a small-molecule chemical inducer, can terminate the cytotoxicity of CD19CAR-T cells over-expressing iCasp9 suicide gene in vivo and in vitro. Methods: CD19CAR-T cells over-expressing iCasp9 (iCasp9-CD19CAR-T) were constructed and co-incubated with AP1903. Then, the cell phenotype and apoptosis were detected by Flow cytometry, and the iCasp9/CID suicide gene system was verified on K562 and T cells, respectively. The cytotoxicity of iCasp9-CD19CAR-T cells was detected in vivo (survival rate of NCG mice bearing Raji cell transplanted xenograft) and in vitro (cell killing function was detected by Flow cytometry) under the administration of AP1903. Results: Compared with CD19CAR-T cells, iCasp9-CD19CAR-T cells showed in significant difference in proliferation, phenotype and cytotoxicity both in vitro and in vivo (all P>0.05). At 2 h after AP1903 administration, the apoptosis rates of K562 and T cells co-expressing iCasp9 and CD19CAR were (33.8±0.9)% and (27.95±0.35)%, respectively; and at 24 h after AP1903 administration, the apoptosis rates reached 100% in both cell lines. The in vitro cytotoxicity of iCasp9-CD19CAR-T cells induced by AP1903 was significantly lower than that without AP1903 treatment (P<0.01); the 60-day survival rate of mice bearing Raji cell transplanted tumor treated with AP1903-induced iCasp9-CD19CAR-T cells was also significantly lower than those treated with iCasp9-CD19CAR-T cells alone (P<0.01). Conclusion: AP1903 can effectively terminate the cytotoxicity of CD19CAR-T cells over-expressing iCasp9 suicide gene in vitro and in vivo.

A giant step forward: chimeric antigen receptor T-cell therapy for lymphoma / 医学前沿

The combination of the immunotherapy (i.e., the use of monoclonal antibodies) and the conventional chemotherapy increases the long-term survival of patients with lymphoma. However, for patients with relapsed or treatment-resistant lymphoma, a novel treatment approach is urgently needed. Chimeric antigen receptor T (CAR-T) cells were introduced as a treatment for these patients. Based on recent clinical data, approximately 50% of patients with relapsed or refractory B-cell lymphoma achieved complete remission after receiving the CD19 CAR-T cell therapy. Moreover, clinical data revealed that some patients remained in remission for more than two years after the CAR-T cell therapy. Other than the CD19-targeted CAR-T, the novel target antigens, such as CD20, CD22, CD30, and CD37, which were greatly expressed on lymphoma cells, were studied under preclinical and clinical evaluations for use in the treatment of lymphoma. Nonetheless, the CAR-T therapy was usually associated with potentially lethal adverse effects, such as the cytokine release syndrome and the neurotoxicity. Therefore, optimizing the structure of CAR, creating new drugs, and combining CAR-T cell therapy with stem cell transplantation are potential solutions to increase the effectiveness of treatment and reduce the toxicity in patients with lymphoma after the CAR-T cell therapy.