Institute for Animal Health, Pirbright Laboratory, Ash Road, Woking, Surrey GU24 0NF, UK.
Vet Microbiol. 2011 Apr 21;149(1-2):242-7. doi: 10.1016/j.vetmic.2010.11.003. Epub 2010 Nov 9.
Characterisation of seven neutralising monoclonal antibodies (mAbs) produced against foot-and-mouth disease virus A(24) Cruzeiro revealed three reactivity groups. Gr-I recognised linear epitopes where as Gr-II was conformation-dependent and trypsin-insensitive. The Gr-III was also conformation-dependent, but trypsin-sensitive. Mar (mAb neutralisation resistant)-mutants could only be produced against Gr-I and Gr-III mAbs. Capsid sequence comparison of Gr-I mar-mutants with parent virus revealed changes in the G-H loop of VP1 at positions 141, 143 and 147. Similarly, a Gr-III mar-mutant showed a change from a highly conserved glycine to a tryptophan at position 148 of VP1 along with three additional changes at the N-terminus of VP1, VP2 and VP4. This residue at 148 of VP1 is located at +2 position after "RGD" and is equivalent to the position identified by the mAb recognising site 5 in serotype O viruses. This site is probably formed because of the interaction of the G-H loop with other residues in different structural proteins.
针对口蹄疫病毒 A(24) Cruzeiro 产生的七种中和单克隆抗体（mAb）的特性研究表明，存在三个反应性组。Gr-I 识别线性表位，Gr-II 是构象依赖性的，且对胰蛋白酶不敏感。Gr-III 也是构象依赖性的，但对胰蛋白酶敏感。仅能针对 Gr-I 和 Gr-III mAb 产生 Mar（mAb 中和抗性）突变体。Gr-I mar-突变体与亲本病毒的衣壳序列比较显示，VP1 的 G-H 环在位置 141、143 和 147 处发生变化。同样，Gr-III mar-突变体在 VP1 的位置 148 处从高度保守的甘氨酸突变为色氨酸，同时在 VP1、VP2 和 VP4 的 N 端还有另外三个变化。VP1 上的这个位置 148 位于“RGD”之后的+2 位，与 O 型病毒中 mAb 识别位点 5 所识别的位置相同。由于 G-H 环与其他结构蛋白中的不同残基相互作用，可能形成了这个位点。
