Reactivity of epidermal growth factor receptor monoclonal antibodies with human uterine tissues

Two monoclonal antibodies (29.1 and 528), which were raised against the epidermal growth factor receptor, were used to evaluate expression of epidermal growth factor receptor in frozen uterine tissue with immunohistochemical techniques. Monoclonal antibody 29.1 stained only vascular endothelium and glandular epithelium in patients who were blood type A. This staining pattern is consistent with the previously reported blood type A specificity of this antibody. Monoclonal antibody 528, which recognizes a peptide determinant is thought to be specific for the epidermal growth factor receptor, stained both endometrial glands and endometrial stromal cells heavily. Faint staining was also seen in myometrium in most cases. This marked difference in expression of epidermal growth factor receptor between endometrium and myometrium contrasts with results of prior biochemical studies in which tissue homogenates were used. No variation in intensity of staining was seen between proliferative and secretory endometrium with the use of either antibody.