动物源Ⅰ型胶原蛋白可引起BALB/c小鼠细胞免疫反应和组织免疫毒性

摘要

背景：天然纯胶原被认为具有较低的免疫原性和较好的生物相容性。目的：体外评估动物源Ⅰ型胶原蛋白的免疫原性。方法：将牛跟腱经免疫原性清除后，提取制成Ⅰ型胶原蛋白，HPLC 测定胶原蛋白纯度，荧光染色定量胶原蛋白中残留DNA。将50只BALB/c小鼠随机均分为5组，分别皮下注射生理盐水(阴性对照)、小牛来源Ⅰ型胶原蛋白标准品(阳性对照)、33.4，66.8，133.4 mg/kg的动物源Ⅰ型胶原蛋白，1次/d，连续注射12 d后，检测注射胶原蛋白后小鼠淋巴细胞的增殖、细胞分型及NK细胞杀伤功能；连续注射3周后，取脾脏、肝脏及肺组织进行病理组织学检查。结果与结论：相比Ⅰ型胶原蛋白标准品，纯化后的牛源性Ⅰ型胶原蛋白纯度可达到99%以上，而残留 DNA低于1 mg/L，远远低于目前常规脱细胞基质中DNA的残留水平50-100µg/g(干质量)。注射12 d后，各组均未发生淋巴细胞增殖、NK细胞杀伤功能及淋巴细胞亚群的比例的变化。注射3周后，66.8，133.4 mg/kg动物源胶原蛋白组小鼠脾小动脉周围淋巴鞘面积明显增厚变大，有可能引发偶发性的肝损伤和肺损伤，而脾小体生发中心面积未发生明显变化。表明连续皮下注射动物源胶原蛋白可引发 BALB/c 小鼠发生较低水平的脾淋巴细胞免疫应答，可能引起偶发性肝、肺损伤。%BACKGROUND:Natural colagen is considered to have low immunogenicity and good biocompatibility relatively. OBJECTIVE:To evaluate the immunogenicity of animal-based colagenin vitro. METHODS:Type I colagen was extracted from bovine tendon after immunogenicity removal. The colagen purity was detected by high performance liquid chromatography and residual DNA was measured quantitatively by fluorescence staining. Fifty BALB/c mice were randomly divided into five groups: subcutaneous injection of normal saline solution (negative control), bovine colagen (positive control), 33.4, 66.8, 133.4 mg/kg of bovine tendon colagen, respectively, once a day. After 12 days of continuously subcutaneous injection, lymphocyte proliferation, and cel classification and NK cel kiling function of mice were detected; after 3 weeks of continuous injection, the spleen, liver, spleen and lung tissue of mice were taken for histological examination. RESULTS AND CONCLUSION:Compared with the standard type I colagen, the purity of purified type I bovine colagen reached more than 99%, but the residual DNA was below 1 mg/L which was far less than the residue level of conventional cel-free DNA in the matrix (dry weight: 50-100 μg/g). After 12 days of continuous injection, there were no changes in lymphocyte proliferation, NK cel kiling function and the proportion of lymphocyte subsets. After 3 weeks of injection, the spleen and lymph sheath of mice around the smal artery became thickened in the 66.8 and 133.6 mg/kg bovine tendon colagen groups, which could cause accidental liver injury and lung injury, but the splenic corpuscle germinal center area had no change. These findings indicate that continuously subcutaneous injection of animal-based colagen can cause the lower lymphocyte immune response to the spleen of BALB/c mice, which may cause accidental liver and lung injuries.