Kooyman D L, McClellan S B, Parker W, Avissar P L, Velardo M A, Platt J L, Logan J S
Nextran, Princeton, NJ 08536, USA.
Transplantation. 1996 Mar 27;61(6):851-5. doi: 10.1097/00007890-199603270-00001.
Gal alpha 1,3 Gal is thought to be the major antigenic epitope present on pig tissues to which XNAs bind. Removal of antibodies directed against that structure may be critical to the success of pig to human xeno-transplantation. As a first step toward the development of ligands capable of removing XNAs, we have used a phage-displayed peptide library to identify a six-amino-acid peptide that binds to the lectin GS-1-B4 (which binds the carbohydrate Gal alpha 1,3 Gal). This peptide blocks the binding of GS-1-B4 to pig aortic endothelial cells. The carbohydrate Gal alpha 1,3 Gal competes with the binding of GS-1-B4 to the peptide, suggesting that they may bind the same site. Using a RBC agglutination assay, we show that this peptide inhibits the agglutination of pig RBCs by heat-inactivated human serum at concentrations similar to that of Gal alpha 1,3 Gal.
α-半乳糖基-1,3-半乳糖（Gal α 1,3 Gal）被认为是猪组织上存在的主要抗原表位，异种天然抗体（XNAs）可与之结合。去除针对该结构的抗体可能对猪到人的异种移植成功至关重要。作为开发能够去除XNAs的配体的第一步，我们使用了噬菌体展示肽库来鉴定一种与凝集素GS-1-B4（可结合碳水化合物α-半乳糖基-1,3-半乳糖）结合的六氨基酸肽。该肽可阻断GS-1-B4与猪主动脉内皮细胞的结合。碳水化合物α-半乳糖基-1,3-半乳糖与GS-1-B4和该肽的结合存在竞争，这表明它们可能结合相同的位点。通过红细胞凝集试验，我们表明该肽在与α-半乳糖基-1,3-半乳糖相似的浓度下可抑制热灭活的人血清对猪红细胞的凝集作用。
