Abaza M S, Young C R, Atassi M Z
Department of Biochemistry, Baylor College of Medicine, Houston, Texas 77030.
J Protein Chem. 1992 Oct;11(5):445-54. doi: 10.1007/BF01025021.
Monoclonal antibodies (mAbs) of predetermined specificity were prepared by immunizing with a free (i.e., not conjugated to any carrier) synthetic peptide representing region 15-22 (site 1) of sperm whale myoglobin (SpMb). The cross-reactions of Mb variants with three mAbs were studied in order to determine whether such interactions are influenced by substitutions outside the site. Finback whale Mb, which has no substitutions within region 15-22, showed lower cross-reactivity and relative binding affinity than the reference antigen, SpMb. Bottle-nose Atlantic dolphin myoglobin (BdMb) and badger myoglobin (BgMb), although they have identical substitutions within region 15-22 (Ala-15 to Gly and Val-21 to Leu), showed very different binding properties. The cross-reaction of BdMb was quite comparable to that of SpMb, while that of BgMb was much lower. Since the two proteins have identical structures in regions 15-22, the differences in their cross-reactivities are readily attributed to the effects of substitutions outside this region. Another pair of myoglobins, horse myoglobins (HsMb) and chicken myoglobin (ChMb), also have two identical substitutions (Ala-15 to Gly and Val-21 to Ile) within region 15-22, but possessed different cross-reactivity. The results indicate that the reaction of mAbs, whose specificity is precisely known and predetermined by the immunizing free peptide, can be markedly affected by substitutions outside the indicated binding region on the protein.
通过用代表抹香鲸肌红蛋白（SpMb）第15 - 22区域（位点1）的游离（即未与任何载体偶联）合成肽进行免疫，制备了具有预定特异性的单克隆抗体（mAb）。研究了肌红蛋白（Mb）变体与三种单克隆抗体的交叉反应，以确定这种相互作用是否受该位点以外的取代影响。在第15 - 22区域内没有取代的长须鲸肌红蛋白，与参考抗原SpMb相比，显示出较低的交叉反应性和相对结合亲和力。宽吻大西洋海豚肌红蛋白（BdMb）和獾肌红蛋白（BgMb），尽管它们在第15 - 22区域（Ala - 15至Gly以及Val - 21至Leu）具有相同的取代，但显示出非常不同的结合特性。BdMb的交叉反应与SpMb相当，而BgMb的交叉反应则低得多。由于这两种蛋白质在第15 - 22区域具有相同的结构，它们交叉反应性的差异很容易归因于该区域以外取代的影响。另一对肌红蛋白，马肌红蛋白（HsMb）和鸡肌红蛋白（ChMb），在第15 - 22区域内也有两个相同的取代（Ala - 15至Gly以及Val - 21至Ile），但具有不同的交叉反应性。结果表明，其特异性由免疫游离肽精确确定和预定的单克隆抗体的反应，可受到蛋白质上所示结合区域以外取代的显著影响。
