[A method of screening highly common neoantigens with immunogenicity in colorectal cancer based on public somatic mutation library].

Colorectal cancer (CRC) is a malignant cancer with high incidence and mortality in the world. Immunotherapy targeting neoantigens can induce durable tumor regression in cancer patients, but is almost limited to personalized precision therapy, due to the individual differences of unique neoantigens. With the discovery of many common oncogenic mutations, and such mutation-associated neoantigens could cover more patients, and hence are valuable in clinical field. However, whether the common neoantigens can be identified in CRC is unknown. Combining the somatic mutations data from 321 CRC patients with a filter standard and 7 predicted algorithms, we screened and obtained 25 HLA-A*1101-restricted common neoantigens with a high binding affinity (IC50<50 nmol/L) and presentation score (>0.90). Besides the positive epitope KRAS_G12V8-16, 11 out of 25 common neoantigens specifically induced in vitro pre- stimulated cytotoxic lymphocyte (CTL) to secrete interferon gamma (IFN-γ). Moreover, combining cell-sorting technology and single-cell RNA sequencing, the immune repertoire profiles of C1orf170_S418G413-421 and KRAS_G12V8-16-specific CTL were analyzed and validated. Their related T-cell receptor engineered T cell (TCR-T) cells could also recognize the neoantigens and secrete IFN-γ. Hence, we have established a method to screen for common neoantigens with immunogenicity in CRC based on the public somatic mutation library. It can provide essential peptide and TCR information for immunotherapies, such as peptides, dendritic cells (DC) vaccines, TCR-like antibodies, TCR-T, etc., for the CRC and other cancers, which has practical application value in the clinics.

[Characteristics of Bacterial Communities in Surface-flow Constructed Wetlands].

Employing high-throughput sequencing as the method, this study analyzed the relationship between the water environment and the microbial community structure in the surface-flow constructed wetland. The results showed that: the mean Shannon-Wiener index was 6.57 and there were mainly 18 categories in the microbial community, including Proteobacterice (38.97%), Bacteroidetes (15.63%) etc. Of these, the total content of 22 genera was over 1%. The microbial biodiversity showed an increasing trend at the beginning and then turned to a decreasing trend in the flowing direction. The results also revealed that pH, ORP, NH4+-N, NO2--N and TN acted as important restricting factors for the microbial community.