[Immunohistochemical study of SP1, HPL and HCG in chorionic tissue with early spontaneous and induced abortions]

Using an indirect enzyme-labeled antibody method, localization of SP1, HPL and HCG in spontaneous abortions (29 cases) was compared with those in induced abortions (39 cases). At the same time, histological changes were examined in the same specimens. 1) Histologically, the fibrinoid degeneration in cytotrophoblastic mass was more often found in spontaneous abortions than in induced abortions. Stromal fibrosis frequently existed in spontaneous abortions (6-10 weeks: 53%, 11-16 weeks: 93%). Stromal edema was rare in induced abortions, but was detected in spontaneous abortions (6-10 weeks: 13%, 11-16 weeks: 50%). These findings were increased with gestational age. 2) Horseradish peroxidase (HRP) reaction products from SP1, HPL and HCG located mainly in the syncytiotrophoblast. The intensity of HRP reaction was not always uniform in each villus. 8% in induced abortions and 59% in spontaneous abortions showed reaction with anti-HCG in some stromas in syncytiotrophoblast. Most of them also showed stromal fibrosis. In spontaneous abortions, the intensity of HRP reaction on HPL was relatively increased in comparison with that on HCG or SP1. In some severe degenerated specimens, SP1 and HPL were found in syncytiotrophoblast, but HCG seemed to be located on the outer part of the stroma adjacent to syncytiotrophoblast.