噬菌体抗原模拟表位的免疫原性研究

目的 通过研究胃癌相关抗原的短肽模拟表位的免疫原性,探讨肿瘤抗原表位的噬菌体模拟肽是否具有免疫原性,为进一步的胃癌疫苗研制奠定实验基础。方法 以胃癌单克隆抗体MG7所识别的胃癌相关抗原表位模拟肽为免疫原,免疫Balb/c小鼠,获得免疫血清;用表达MG7单抗所识别的相应抗原的胃癌组织切片,通过免疫组化方法筛选免疫血清;在此基础上,对阳性血清进一步用细胞荧光标记法和ELISA法进行了检测,结果 免疫血清经免疫组化筛选和细胞荧光标记法及ELISA法检测,发现其中一个噬菌体呈现的表位模拟肽的免疫血清可与人胃癌组织间呈现特异的免疫反应,由此筛选出具有免疫原性的胃癌相关抗原表位的噬菌体模拟肽。结论 用单克隆抗体从随机肽库中筛选得到的部分表位模拟肽具有引发识别厮的始抗原免疫反应的免疫原性,提示以肿瘤相关抗原的表位模拟肽为基础研制疫菌具有可行性,可望在机体内诱发有效的体液免疫反应。

Immunogenicity of phage-displayed tumor antigen-mimic peptide

Objective To determine the immunogenicity of phage displayed tumor antigen mimic peptide, and to lay experimental foundation for the development of gastric cancer vaccine. Methods Based on previous studies, two phage displayed peptide libraries were screened and 12 and 30 positive phage clones obtained from two libraries respectively. All the positive phages were purified and used them to immunize Balb/c mice. The immune serum was screened by immunohistochemical with tissue sections of human gastric cancer expressing MG7 antigen. The result was further confirmed by fluorescence labeling and ELISA.Results Through immunohistochemical screening of immune sera with tissue sections of human gastric cancer, one phage displayed mimic peptide was able to elicit production of antibody specific for human gastric cancer.Conclusion The result demonstrates that it is possible to develop tumor vaccine based on antigen epitope mimic peptide with immunogenicity.