Structural Physiology Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8566, Japan.
Department of Biochemistry, Bio-Peak Co., Ltd., 584-70 Shimonojo, Takasaki 370-0854, Japan.
Molecules. 2019 Aug 14;24(16):2949. doi: 10.3390/molecules24162949.
Monoclonal antibodies with high affinity and specificity are essential for research and clinical purposes, yet remain difficult to produce. Agretope peptides that can potentiate antigen-specific antibody production have been reported recently. Here, we screened in silico for peptides with higher affinity against the agretope binding pocket in the MHC-II. The screening was based on the 3D crystal structure of a complex between MHC-II and a 14-mer peptide consisting of ovalbumin residues 323-339. Using this 14-mer peptide as template, we constructed a library of candidate peptides and screened for those that bound tightly to MHC-II. Peptide sequences that exhibited a higher binding affinity than the original ovalbumin peptide were identified. The peptide with the highest binding affinity was synthesized and its ability to boost antigen-specific antibody production in vivo and in vitro was assessed. In both cases, antigen-specific IgG antibody production was potentiated. Monoclonal antibodies were established by in vitro immunization using this peptide as immunostimulant, confirming the usefulness of such screened peptides for monoclonal antibody production.
单克隆抗体具有高亲和力和特异性，是研究和临床应用的必备工具，但仍然难以生产。最近有报道称，具有增强抗原特异性抗体产生能力的共同表位肽。在这里，我们通过计算机筛选了针对 MHC-II 共同表位结合口袋的高亲和力肽。筛选基于 MHC-II 与由卵清蛋白残基 323-339 组成的 14 肽复合物的 3D 晶体结构。使用该 14 肽作为模板，我们构建了候选肽文库，并筛选与 MHC-II 紧密结合的肽。鉴定出与原始卵清蛋白肽结合亲和力更高的肽序列。合成了结合亲和力最高的肽，并评估了其在体内和体外增强抗原特异性抗体产生的能力。在这两种情况下，抗原特异性 IgG 抗体的产生都得到了增强。使用该肽作为免疫刺激剂通过体外免疫，建立了单克隆抗体，证实了筛选出的肽在单克隆抗体生产中的有用性。
