蓖麻凝集素的纯化及其对肺癌血清末端Galβ1-4GlcNAc糖链的测定

Purification of ricinus communis agglutinin from castor bean and its application in research of oligosaccharides in serum of patients with lung cancer

作者应用生物化学方法从中药蓖麻籽中分离纯化蓖麻凝集素,经SDS-PAGE和血球凝集试验鉴定纯度及活性后,用亲和层析法获得的蓖凝集素识别的糖蛋白.用蓖麻凝集素和辣根过氧化物酶标记的糖蛋白建立了一种血清末端Galβ1-4GlcNAc糖链分子ELISA检测方法.对肺癌.良性肺部疾病患者和正常人血清检测结果证实:肺癌患者血清中蓖麻凝集素识别的末端Galβ1-4GlcAc糖链分子表达明显增加.以正常人组血清检测平均值加2个标准差之和(11-5×2=21U ml)作为判断肿瘤的阳性阀值.肺癌阳性率为60.6％(20/33);良性肺部疾病21.4％(6,28);正常人仅为4.0％(1 25).它的检测和分析对肺癌标志物的寻找及其发病机理的探讨具有一定意义.

In this report , the ricinus communus agglutinin (RCA1) purified from castor beans was employed to ana-lyze oligosaccharide molecules in scrum of patients with lung cancer and benign diseases . By DHAF - scphadcx A50 and scphadcx G- 100 chromatography. RCA1 was purified from the extracts of castor beans.After characterizing its bioacuvity by red blood coagglutination and purification by SDS-PAGE, RCA1 was coupled with CNBr - activated scpharosc 4B With RCA1 affinity chromatography, the glycoprotcins containing Galβ1 - 4G1cNAc - linked unit at nonrcducing end of carbohydrate chain . were isolated from gastric cancer tissue . By RCA1 and this glycoproicins labelled with pcroxidasc . a competitive binding assay was established and employed to detect the level of the oligosaccharidcs defined by RCA1 in scrum of patients with lung cancer . benign diseases and normal persons. The results suggest that expression of this oligosaccharidc molecules is higher in scrum of patients with lung cancer than that in scrum of patients with benign disease of respiratory system and healthy individulc. The positive rates are 60.6% (20. 33 )in sera of patients with lung cancer , 21.4% (6 28 )in benign di -scascs and 4.0% (1/25 )in normal persons. It is confirmed that detection of this oligosaccharidc molecules in scrum can be helpful in study and diagnosis of lung cancer .