抗活化血小板单克隆抗体与尿激酶杂合分子的纤溶作用

用双功能团试剂将尿激酶(UK)B链和抗人活化血小板α-颗粒膜蛋白GMP-140单克隆抗体(SZ-51)的Fab片段共价偶联。偶联的杂合分子UK-SZ-51保留了原抗体的结合专一性,它在体外的溶栓效率较尿激酶提高约5倍,其溶栓作用对血浆中纤维蛋白原的含量无影响。     

抗人血小板单克隆抗体的研究——Ⅱ.抗血小板糖蛋白Ⅰ单克隆抗体——SZ-2

单克隆抗体SZ-2特异作用于人血小板和巨核细胞,测定10例正常人血小板SZ-2结合位点数为15200±4100/血小板,KD值0.66±0.33nM。SZ-2所识别的抗原对糜蛋白酶敏感,但对神经氨酸酶不敏感,亲和层析技术证明其为血小板糖蛋白Ib(GPIb)。SZ-2与其它抗GPIb单克隆抗体不同,它不仅抑制瑞斯托霉素诱导的血小板聚集,而且也抑制Ⅰ型胶原和血小板活化因子诱导的血小板聚集,并抑制上述诱导剂引起的血小板5-HT和βTG释放。     

Hybridization to an Anti-activated Platelet Monoclonal Antibody Enhances Fibrinolytic Potency on Urokinase

The B-chain of urokinase (UK) was covalently linked by disulfide bond to the Fab fragment of an anti-human activated platelet monoclonal antibody(SZ-51). The UKSZ-51 conjugate retained the original binding specificity of its parent antibody, and produced about a 5-fold enhancement in clot lysis in plasma over that of the urokinase in vitro. Whereas UK significantly decreased the concentration of fibrinogen in plasma clot assay supernatants, UK-SZ-51 did not.     

STUDIES ON MONOCLONAL ANTIBODIES AGAINST HUMAN PLATELETS——A MONOCLONAL ANTIBODY TO HUMAN PLATELET GLYCOPROTEIN I——SZ-2

A monocloual antibody, SZ-2, reacts specifically on human platelets and megakaryocytes. The plate-lets from 10 normal donors are bound to 15,200±4,100 SZ-2 molecules/platelet. The antigen recognizedby SZ-2 is chymotrypsin-sensitive but neuraminidase-insensitive, and has been identified as glycoproteinIb (GPIb) by an affinity chromatography technique. SZ-2 is different from other monoclonal antibodiesto GPIb. It inhibits not only platelet aggregation induced by ristocetin, but also platelet aggregation in-duced by collagen (type Ⅰ) and by PAF. SZ-2 also inhibits platelet serotonin and β-thromboglobulinrelease in response to these stimuli.