Immunohistochemical analysis of estrogen and progesterone receptors in endometrium and peritoneal endometriosis: a new quantitative method.

OBJECTIVE: To evaluate estrogen receptors (ER) and progesterone receptors (PR) content in glandular and stromal cells of eutopic and ectopic endometrium. DESIGN: A recently advanced stereographic computer technology was applied for the investigation of steroid receptors. SETTING: University hospital department of gynecology. PATIENTS: Biopsies of endometrium and typical peritoneal endometriotic lesions were taken from 19 infertile patients with laparoscopically proved endometriosis. Endometrial biopsies were also taken from 15 patients without endometriosis. All of them were untreated. RESULTS: In normal endometrium, the highest concentrations of ER and PR occurred in the epithelial and stromal cells during the late proliferative phase of the menstrual cycle. Estrogen receptor and PR content declined throughout the secretory phase. Progesterone receptor content was found not to be significantly decreased in the stroma during the early secretory phase and quite high in the late secretory phase. In peritoneal endometriotic lesions, the highest concentrations of ER and PR were found during the late proliferative phase. When compared with normal endometrium, a lower ER content ans a similar PR content were observed, and the cyclic changes in peritoneal endometriosis lesions were also similar. CONCLUSION: A new computerized technology for the evaluation of ER and PR in eutopic and ectopic endometrium. Although the ER content was found to be lower in endometriotic tissue when compared with endometrium, the cyclic pattern was similar in both eutopic and ectopic endometrium. Progesterone receptor content was similar in both tissues, except during the late secretory phase in ectopic glandular epithelium in which a high persistent PR content was observed.

Determination of antigen concentration in tissue sections by immunodensitometry.

Our aim was to determine whether density of immunolabeling can be used to estimate the amount of an antigen in a tissue. The biological model was the pancreatic insulin-containing B cell. The insulin content of the pancreas of Wistar rats was decreased by five injections of glibenclamide (0.5, 1, or 2 mg/kg) every 12 hours. After resection of the whole pancreas specimens were taken for insulin extraction and measurement by radioimmunoassay and for immunocytochemistry. The sections were treated either by a polyclonal anti-insulin serum at 1/500 or 1/3000 and peroxidase-antiperoxidase complex or by a monoclonal anti-insulin serum at 1/500 and indirect immunoperoxidase. Peroxidase was revealed by diaminobenzidine. The density of immunostained B cells was determined with an automatic image analyzer (Ibas 2000, Kontron, FRG). Compared with controls, pancreatic insulin concentration was decreased by about 40, 60, and 85% in rats treated by the three doses of glibenclamide. A strong correlation was found between the insulin concentration and the optical density of islets under certain conditions: with the monoclonal anti-insulin serum (r = 0.90) and with the polyclonal anti-insulin serum at a high dilution (r = 0.95) but not at a low dilution (r = 0.13). With the latter, the optical density was high even in islets with reduced insulin content. In conclusion, a low dilution of antiserum should be used to detect cells with a small amount of antigen, whereas a higher dilution makes it possible to estimate the antigen concentration in the tissue. Thus, under appropriate conditions, a linear relationship exists between the optical density of the immunostained material and the concentration of immunoassayable antigen. This technique may thus prove useful in evaluating the functional state of cells, in particular secretory cells, under normal or pathological conditions.