[Production and application of mouse antiserum to human estrogen receptors]

An antiserum to peptide containing 15 amino acids corresponding to the region-D of human estrogen receptors (hERD) was obtained in mice by immunization with the peptide conjngated to KLH. Using this antiserum, the ER status of paraffin-embeded sections of 95 human breast carcinomas (in which, sections of 31 were both frozen and paraffin-embeded ones) were studied. The corresponding rate for determination of ER status between immunohistochemical staining (IHC) and dextran coated charcoal (DCC) assay was 89.5%. The concordance rate for semiquantitative gradings was 69.3%. In addition, in situ hybridization (ISH) of 15 frozen sections of the samples using digoxigenin labeled dUTP to identify the expression of ER mRNA was also done. The result of ISH was fully consistent with that of IHC (100%). The results show that the mouse antiserum to hERD obtained in this study is specific and sensitive for IHC assay of ER and IHC is a valuable adjunct and/or alternative to the biochemical method for determination of the ER status of breast cancer.