[Optimization of CD19 chimeric antigen receptor T cell establishment and observation of the killing effect in vitro and in vivo].

Objective: To optimize the stimulation and activation system of mouse CD3(+) T cells in vitro and explore the optimal infection time of CD3(+) T cells to establish mouse CD19 chimeric antigen receptor T cells (mCD19 CAR-T) , and to also verify its killing effect in vivo and in vitro. Method: Splenic CD3(+)T cells were isolated and purified using magnetic beads, and the cells were cultured in Soluble anti-CD3/CD28, PMA+Ionomycin, and Plated anti-CD3/CD28. Cell activation and apoptosis were assessed by flow cytometry after 8, 24, 48, and 72 hours. ScFv plasmid of mouse CD19 antibody was transfected to plat-E cells to package retrovirus. Activated CD3(+) T cells were infected to construct mouse-specific CD19 chimeric antigen receptor T cells (mCD19 CAR-T) , and mCD19 CAR-T cells were co-cultured with B-cell lymphoma cell line A20 in vitro. The specific toxicity of A20 was detected by flow cytometry, and mCD19 CAR-T cells were infused into the lymphoma mouse model to detect its killing effect and distribution. Results: The activation effect of Plated anti-CD3/CD28 on CD3(+) T cells was superior, with the cells exhibiting good viability 24-48 hours after stimulation. Established mCD19 CAR-T cells with stable efficiency[ (32.27±7.56) % ] were specifically able to kill A20 tumor cells (The apoptosis rate was 24.3% at 48 h) . In vivo detection showed a non-significant decrease in the percentage[ (1.83±0.58) % ] of splenic CD19(+) cells 6 days after mCD19 CAR-T cell infusion. A marked clearance in bone marrow and spleen appeared on day 12 compared with the A20 group, and this difference was statistically significant[spleen: (0.36±0.04) % vs (47.00±13.46) % , P<0.001; bone marrow: (1.82±0.29) % vs (37.30±1.44) % , P<0.0001]. Moreover, mCD19 CAR-T cells were distributed in high proportions in the peripheral blood, spleen, and bone marrow[ (2.90±1.12) % , (4.96±0.80) % , (13.55±1.56) % ]. Conclusion: This study demonstrated an optimized activation system and the optimal infection time of CD3(+) T cells. Furthermore, stable constructed mCD19 CAR-T cells showed a remarkable killing ability in vitro and in vivo.

[Clinical application of TCGA molecular classification in endometrial endometrioid carcinoma].

Objective: To explore molecular characteristics of endometrial endometrioid cancer according to The Cancer Genome Atlas (TCGA) based molecular classification of endometrial carcinomas and to confirm simple and clinically applicable surrogate methodologies in pathological practice. Methods: Two hundred and twenty-eight cases of endometrial endometroid adenocarcinomas (EnACs) collected from August 2001 to August 2017 from Peking University Health Science Center, Peking University Third Hospital were molecularly categorized by using Sanger sequencing for the exonuclease domain mutations (EDM) of POLE, and by immunohistochemistry for p53 and mismatch repair (MMR) proteins. The cohort was classified into polymerase-E exonuclease domain mutation (POLE EDM), mismatch repair deficiency (MMR-D), p53 abnormal (p53-abn) and p53 wild type (p53-wt) groups. The correlation between molecular subgroups and the clinical-pathological features including prognosis were analyzed. Results: The cohort was distributed as follows: 11(4.8%) POLE EDM, 47(20.6%) MMR-D, 9(4.0%) p53-abn and 161(70.6%) p53-wt. p53-wt subgroup patients demonstrated significantly higher lymph node metastasis (P=0.011) and more advanced stage (P=0.036) than those of somatic hypermutation group cases (POLE EDM and MMR-D). In the FIGO grade 2-3 EnACs cohort, TCGA molecular subtyping was significantly correlated with progression-free survival and overall survival (P=0.043). POLE EDM subgroup had the best survival, while p53-abn subgroup had the worst. Conclusions: Identification of POLE EDM and MMR-D subgroups provides independent and highly valuable prognostic information beyond established histological classification. Based on immunohistochemistry of MMR, p53 and POLE mutational analysis, this pragmatic molecular classification scheme can be served as a reliable surrogate for TCGA molecular classification, which has potential to be used routinely in Chinese pathological practice.