Characterization of Distinct T Cell Receptor Repertoires in Tumor and Distant Non-tumor Tissues from Lung Cancer Patients / 基因组蛋白质组与生物信息学报·英文版

T cells and T cell receptors (TCRs) play pivotal roles in adaptive immune responses against tumors. The development of next-generation sequencing technologies has enabled the analysis of the TCRβ repertoire usage. Given the scarce investigations on the TCR repertoire in lung cancer tissues, in this study, we analyzed TCRβ repertoires in lung cancer tissues and the matched distant non-tumor lung tissues (normal lung tissues) from 15 lung cancer patients. Based on our results, the general distribution of T cell clones was similar between cancer tissues and normal lung tissues; however, the proportion of highly expanded clones was significantly higher in normal lung tissues than in cancer tissues (0.021% ± 0.002% vs. 0.016% ± 0.001%, P = 0.0054, Wilcoxon signed rank test). In addition, a significantly higher TCR diversity was observed in cancer tissues than in normal lung tissues (431.37 ± 305.96 vs. 166.20 ± 101.58, P = 0.0075, Mann-Whitney U test). Moreover, younger patients had a significantly higher TCR diversity than older patients (640.7 ± 295.3 vs. 291.8 ± 233.6, P = 0.036, Mann-Whitney U test), and the higher TCR diversity in tumors was significantly associated with worse cancer outcomes. Thus, we provided a comprehensive comparison of the TCR repertoires between cancer tissues and matched normal lung tissues and demonstrated the presence of distinct T cell immune microenvironments in lung cancer patients.

Research progress on negative regulation of adaptive immune response by NK cells / 中国免疫学杂志

Natural killer ( NK) cells are important innate effector cells and play a vital role in maintaining homeostasis through potent cytotoxic activity and cytokine production. Recent findings show that NK cells can also shape adaptive immune responses by in-fluencing a variety of immune cells. In addition to direct interactions with other immune cells,NK cells can indirectly stimulate or inhibit adaptive immune response via influencing infected cells and pathogen load. Abundant studies have highlighted the positive regulatory functions of NK cells, while their negative regulatory functions have increasingly attracted attention in recent years. Here, we review recent findings on negative regulation of adaptive immune response by NK cells, discussing the involved effector cells and function mechanism,and demonstrate how this negative regulation influences the overall outcome of adaptive immunity in infection and tumor disease.