Screening and predication on tumor neoantigen for primary plasma cell leukemia / 中国肿瘤生物治疗杂志

@#Objective:To investigate the tumor-specific neoantigen for primary plasma cell leukemia (PCL) using gene sequencing technology combined with bioinformatic analysis. Methods: Peripheral blood samples of one patient with primary PCL during relapse and remission periods were collected. HLA molecular typing was performed using polymerase chain reaction with sequencing-based typing; whole-exome and transcriptome were sequenced by next-generation sequencing method; and bioinformatics software NetMHCpan was used to predict neoantigens. Results: Six tumor-specific missense mutations were found in the patient's peripheral blood during relapse period, located in genes FRG1, MLL3, SVIL, MYOM1, ZDHHC11 and RFPL4A.Considering patient's HLA sub-types, 43 neoantigens were predicted via bioinformatics. Considering that FRG1 and MLL3 had relatively high gene expression levels, 20 neoantigens derived from mutations of the two genes were preferentially selected, among which four neoantigens had high affinity with the patient's HLA molecules and thus had potential clinical application value. Conclusion: The study has completed a tumor neoantigen screen and prediction for primary PCL. This practice demonstrates that predicting neoantigen based on tumor-specific somatic mutation is feasible for primary PCL.

In vitro construction and amplification and primary functional analysis of antiCD19 chimeric antigen receptor(CD19-CAR) modifiedTcells / 中国肿瘤生物治疗杂志

@#[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.