Immunocytochemical demonstration of estrogen receptor β in human periodontal ligament cells

Two transcription associated estrogen receptor (ER) subtypes have been identified and named ERα and ERβ. In the present study we investigate the expression of these ER subtypes in cultured human periodontal ligament (PDL) cells by immunocytochemistry. ERβ immunoreactivity was observed in the nuclei of about 40% of the PDL cells, while no ERα immunoreactivity was detected. In human breast cancer MCF-7 cells, serving as positive controls, both ERα and ERβ immunoreactivities were demonstrated. No immunoreactivity was observed after omission of the primary antibodies. This study suggests that estrogen acts on gene transcription preferentially via ERβ in human PDL cells.