抗核抗体（ANA）是免疫失衡的特征性指标，免疫失衡与肿瘤发生发展密切相关，但是ANA能否自主进入活细胞及其对肿瘤的调控作用仍无报道。我们已筛选并制备出5种全人单克隆ANA，通过与活细胞共孵育发现其能够进入活细胞内，且体内外实验均发现这些ANA可抑制多种肿瘤细胞增殖。因此我们推测ANA可能通过自主入胞/核直接发挥抗肿瘤作用，或通过调节免疫间接发挥抗肿瘤作用。本课题用上述ANA拟进行：① 实时监测ANA入胞/核活动；② 分析ANA核定位信号、Fc受体等特征性序列，通过序列敲除等方法明确ANA入胞/核机制；③ 免疫学方法鉴定ANA靶点蛋白，突变或截短靶蛋白验证其功能；④ 体内外验证ANA对免疫细胞和肿瘤细胞的调控作用，并评价ANA的生物安全性。本研究将从直接入胞/核、间接免疫调控两方面评价ANA在抗肿瘤方面的潜在应用，为明确ANA入胞/核及机制提供可靠依据，为肿瘤靶向精准治疗提供新的分子靶点。

The abundant antinuclear antibodies (ANA) is a characteristic index of immune imbalance, which is closely related to pathogenesis of tumors. However, the cellular penetration of ANA and the relevant regulation to tumor cell still remains unclear. We have prepared 5 kinds of fully human monoclonal ANA. Through in vivo and in vitro experiments, we found these ANA could penetrate into the living tumor cells, and suppress the tumor cell proliferation. Therefore, we speculate that ANA could exert an antitumor effect by the penetration into tumor cell directly, or by the immune regulation indirectly. In this study, we will use these ANA to do follow experiments: ① observe the cellular/nuclear penetration of ANA; ② analyze the characteristic sequence (nuclear localization signal, Fc receptor binding sequence and so on), and further, knockout the characteristic sequence and clarify its cellular/nuclear penetration mechanism; ③ to identify the target antigens of ANA, and confirm its function by the mutation and truncation; ④ to detect the regulatory effects of ANA on the immune cells and tumor cells. and the biological safety assess of ANA will be detected by in vivo experiments. We will evaluate the potential application of ANA by two aspects, including the direct penetration and indirect regulation of immune microenvironment. This study will provide reliable evidence for cellular/nuclear penetration mechanism, and provide molecular targets for tumor treatment.