Differentiation of CEA and CEA-Related Substances by Western Blot Technique in Biliary and Gastric Diseases / 中国普外基础与临床杂志

ABSTRACT

Objective To eliminate the interference of CEA-related substances in CEA measurement and increase the specificity of CEA in the detection of malignant digestive diseases.Methods CEA level of peripheral blood and digestive juice(bile,gastric juice) from patients with benign or malignant digestive diseases was measured by ELISA,and semi-dry electrophoretic transfer method of Western blot technique to distinguish CEA and CEA-related substances.Results In malignant diseases,the CEA level of digestive juice was significantly higher than that in the blood,and there was no difference of CEA level in digestive juice and blood in benign diseases.Meanwhile,the CEA level of digestive juice and blood in malignant diseases were significantly higher than that in benign diseases.A specific band(molecular weight about 210?10~3) was detected in all malignant diseases except four cases whose CEA level was too low(less than 5 ?g/L),whereas no one of benign diseases had this specific band no matter how high or low the CEA level was.Conclusion The specificity of CEA detection in malignant digestive diseases can be improved by using digestive juice as sample and combining with Western blot technique.