摘要
目的 研究一株新制备的抗人血小板第4因子(PF4)单克隆抗体(mAb)SZ-95的抗原表位和对PF4结合肝素功能的影响。 方法通过间接ELISA、Western blot以及肝素-PF4复合物ELISA研究SZ-95所识别的抗原决定簇和其对PF4生物学功能的影响。 结果 这株特异性识别人PF4的mAb不识别与PF4高度同源的β-血小板球蛋白(β-TG),以及包括PF4分子中部大部分β折叠的合成多肽(P34-58)。并且,抗体结合肝素-PF4复合物的数量随复合物中的肝素量增加而减少。结论我们推测SZ-95识别的抗原表位可能位于人PF4 N末端的可变区域或者C末端α螺旋。并且mAb结合肝素-PF4复合物的肝素剂量依赖性改变,说明SZ-95识别的抗原表位与肝素与PF4的结合位点有关,可能影响PF4中和肝素的功能,有助于PF4结构和功能的进一步研究。
Aim To identify the epitope recognized by a novel monoclonal antibody SZ-95 against Platelet Factor 4(PF4) and to study its effect on PF4 binding to heparin. Methods The epitope of SZ-95 and its action on biological activities of PF4 was determined by indirect ELISA,Western blot and heparin-PF4 complex ELISA.Results The mAb SZ-95 recognizing human PF4 specifically does not react with beta-thromboglobulin(β-TG) and the synthetic peptide corresponding to amino acids 34 to 58 (P34-58). The number of SZ-95 binding to heparin-PF4 complex reduces along with the increment of heparin in complex. Conclusion It is suggested that the epitope of SZ-95 locate in the carboxylterminal α-helix or conformation flexible N-terminal region.The quantity of SZ-95 binding to heparin-PF4 complex dependent on the number of heparin in complex demonstrated that the epitope of SZ-95 is related to the binding site of PF4 on heparin.The effect of SZ-95 on PF4 binding to heparin provides evidence for further study fo structure and function of PF4.
出处
《细胞与分子免疫学杂志》
CAS
CSCD
北大核心
2002年第2期165-167,共3页
Chinese Journal of Cellular and Molecular Immunology