Chimeric antigen receptor T cell targeting EGFRvIII for metastatic lung cancer therapy / 医学前沿

Lung cancer is the most common incident cancer and the leading cause of cancer death. In recent years, the development of tumor immunotherapy especially chimeric antigen receptor T (CAR-T) cell has shown a promising future. Epidermal growth factor receptor variant III (EGFRvIII) is a tumor-specific mutation expressed in various types of tumors and has been detected in non-small cell lung cancer with a mutation rate of 10%. Thus, EGFRvIII is a potential antigen for targeted lung cancer therapy. In this study, CAR vectors were constructed and transfected into virus-packaging cells. Then, activated T cells were infected with retrovirus harvested from stable virus-producing single clone cell lines. CAR expression on the surfaces of the T cells was detected by flow cytometry and Western blot. The function of CAR-T targeting EGFRvIII was then evaluated. The EGFRvIII-CAR vector was successfully constructed and confirmed by DNA sequencing. A stable virus-producing cell line was produced from a single clone by limited dilution. The culture conditions for the cell line, including cell density, temperature, and culture medium were optimized. After infection with retrovirus, CAR was expressed on more than 90% of the T cells. The proliferation of CAR-T cells were induced by cytokine and specific antigen in vitro. More importantly, EGFRvIII-CART specifically and efficiently recognized and killed A549-EGFRvIII cells with an effector/target ratio of 10:1 by expressing and releasing cytokines, including perforin, granzyme B, IFN-γ, and TNF-α. The in vivo study indicated that the metastasis of A549-EGFRvIII cells in mice were inhibited by EGFRvIII-CART cells, and the survival of the mice was significantly prolonged with no serious side effects. EGFRvIII-CART showed significantly efficient antitumor activity against lung cancer cells expressing EGFRvIII in vivo and in vitro. Therefore, CAR-T targeting EGFRvIII is a potential therapeutic strategy in preventing recurrence and metastasis of lung cancer after surgery.

Establishment of High-throughput Model for Anaphylactic Reaction in Vitro and Evaluation of Potential Anaphylactogen Isoliensinine / 中国中医药信息杂志

Objective To establish a high-throughput evaluation model for anaphylactic reactions; To screen and identify potential anaphylactogens from TCM monomeric compounds.MethodsCell model of stably expressed MrgX2 was established. Recombinate plasmid pmCherry-C1-MrgX2 was transfected to HEK293 to establish cell line for screening model. MrgX2 agonist and antagonist were used to identify the validation and stability of the cell line. A small library consisting of 180 compounds was profiled by using a cell-based calcium mobilization assay to find novel compounds targeting the MrgX2 receptor. EC50 test, IC50 test, specificity validation and cytotoxicity evaluation were carried out to detect the function of the positive agonist.ResultsThe EC50 of C48/80 to MrgX2 model was 2.7 μg/mL and the IC50 of 2-APB (evoked by 10 μg/mL C48/80) was 46.29 μmol/L. The first generation cell model of MrgX2 was similar to the 20th generation, and the Z factor of MrgX2 cell model was 0.78. In the primary screening for agonist, isoliensinine was identified as a novel agonist targeting receptor MrgX2 with an EC50 of 4.5 μmol/L and IC50 of39.47 μmol/L. Moreover, isoliensinine was validated to activate MrgX2 receptor specifically without cytotoxicity. Conclusion A high-throughput evaluation method for anaphylactic reactions can be established in vitro through calcium mobilization assay. A potential anaphylactogen isoliensinine is identified and validated.

Inhibitory Effect of Oleanolic Acid on Lipid Accumulation in Cytoplasm of 3T3-L1 Adipocyte / 世界科学技术-中医药现代化

A collection of 57 natural compounds derived from Chinese herbal medicines were evaluated for their an-ti-adipogenic effects. The lipid droplets in differentiated 3T3-L1 adipocytes treated with tested substrate were de-tected by an image-based assay. The results demonstrated that oleanolic acid (OA) inhibited lipid droplets accumula-tion in 3T3-L1 adipocytes in a dose-dependent manner with the IC50 value of 14.5 μmol·L-1. In addition, ToxInsight assay showed that OA was free of liver injury for HepG2 cells within 60 μmol·L-1. It was concluded that OA, which had an obvious anti-adipogenic effect, can be a candidate for hyperlipidemia therapy.