Atypical Cilia in Human Endometrium

Motile cilia throughout the bios possess a constant number of fibrils which are arranged in a regular and consistent pattern. Yet, during a study on the fine morphological changes of human uterine epithelium in different phases of the cycle, we observed an impressive number of cilia showing a wide variety of structural anomalies previously unreported in a mammalian tissue. Such a conspicuous deviation from the normal may be relevant for an evaluation of the function of the ciliated cells of the human endometrium. The study was performed on 17 endometrial biopsies obtained from 15 patients in reproductive age at different stages of the menstrual cycle. The patients were seen for minor gynecological affections , none of which included abnormal uterine bleeding or endometritis. Two patients were biop-sied twice in the course of our study. Fragments of endometrium, obtained randomly from the uterine cavity by the suction method, were immediately diced into small blocks which were fixed in 1% OsO4 with salts added (17), or in 2.5 % glutaralde-hyde in 0.1 M cacodylate buffer (12). Glutaralde-hyde fixation was followed by postosmication of the tissue. Embedding was performed in Epon 812 (8). The thin sections were stained with lead hydroxide (6) and studied with Hitachi HU 11A and HU 11C electron microscopes. Anomalous cilia were found in 10 of 15 patients, and their presence could not be related to any particular stage of the cycle. One of the patients was biopsied twice during the same cycle and showed cilia abnormalities in both tissue samples. In the positive cases, the structural defects were present in a large number of cells, where they often involved the majority of cilia (Fig. 8). Anomalies were found in the shaft of the cilium as well as in the apical cytoplasm of the ciliated cells. A detailed description of the wide variety of defects observed in the ciliary shafts would be beyond the scope of this report. In essence the defects were represented by the following: (a) aberrations of the number of elements of the axial complex, which were of the plus type (Figs. 1 and 3) or of the minus type (Figs. 2, 4-6); (b) abnormal arrangement of the fibrils of the axial complex (Figs. 1, 8, and 12); and (c) abnormal structural characteristics of the fibrils of the axial complex (Fig. 1). Two or more anomalies were occasionally found in the same ciliary shaft. Fig. 7, …