Effects of high dose progestogens on white cells and necrosis in human endometrium.

Endometrium was collected from 20 high-dose progestogen-treated patients and examined for leukocyte populations by immunohistochemistry and phloxine-tartrazine staining. A labelled streptavidin-biotin-alkaline phosphatase technique was used with antibodies against leukocyte common antigen (LCA), T cells (CD3), neutrophils (NP57), macrophages] (CD68, KP1) and B cells (CD20). The numbers of LCA (1070 +/- 117/mm2), CD3 (459 +/- 60/mm2), CD68 (129 +/- 21/mm2) positive cells and endometrial granulated lymphocytes (EGL) (236 +/- 41/mm2) were significantly higher than those in the control group (P < 0.001). Of these, EGL increased most (6.7 times). NP57 positive (NP57+) neutrophils were present in five out of 20 progestogen-treated samples and NP57 negative (NP57-) neutrophils in another six out of 20; while a neutrophil was only identified in one control tissue (P = 0.002). Three progestogen-exposed endometrial samples had either focal or extensive necrosis, and many NP57+ and NP57- neutrophils were present in the necrotic areas. EGL, neutrophils and macrophages are known to release a number of cytolytic and cell toxic molecules which may play a role in the initiation or acceleration of progestational endometrial necrosis.