DNA SEGMENT ENCODING ERB-3 POLYPEPTIDE, AND ANTIBODY AND BIOASSAY FOR DETECTING THE ABOVE POLYPEPTIDE

摘要

PROBLEM TO BE SOLVED: To obtain a DNA segment encoding the receptor protein relevant to an erbB protooncogene system which is unknown in the past or not predicted even being present and further to develop a method of analyzing for the gene protein product capable of determining whether or not the expression of RNA and the abnormal expression of the above oncogene are contained in a human cancer. SOLUTION: This DNA segment is an antibody or its active fragment specifically combining with erbB-3 polypeptide and the bioassay comprises forming the complex between an antibody or its active fragment not specifically combining with erbB-2 polypeptide or erbB polypeptide, or the above antibody or its active fragment and the erbB-3 to detect the erbB-3 in a biological sample by the presence of the complex.