A Quantitative Assessment of the Morphological Characteristics of BeWo Cells as an in vitro Model of Human Trophoblast Cells

• Published in: International journal of morphology 2010-12, Vol.28 (4), p.1047-1058
• Main Authors: Abaidoo, C.S, Warren, M. A, Andrews, P. W, Boateng, K. A
• Format: Article
• Language: English
• Subjects: ANATOMY & MORPHOLOGY
• ISSN: 0717-9502; 0717-9502
• DOI: 10.4067/S0717-95022010000400011

In order to study the detailed morphology of trophoblast cells during human implantation, BeWo cells were cultured as spheroids in suspension culture. These cultures were then processed for light and electron microscopical examination. The present study showed that the BeWo spheroids consist of two cell types which are cytotrophoblast-like and syncytiotrophoblast-like. The cells with larger nuclear diameter made up only about 1% of the cell population and appear to be those of syncytiotrophoblast. Therefore the predominant cell type of the BeWo spheroids appeared to be relatively undifferentiated and cytotrophoblast-like. About 10% of the BeWo cells in the present study were mitotic, indicating a highly proliferative population. Total cell number increased about 12 times during the culture period from 107 ± 9 on day 1 to 1211 ± 145 on day 7 whereas the volume per cell increased about 2 times, from 1300 µm3 on day 1 to 2400 µm3 on day 7. Therefore overall growth of BeWo spheroids is due to both hyperplasia and hypertrophy. However, it appears that cell proliferation outstrips volumetric growth. These quantitative data show that BeWo cells grow mainly by hyperplasia and provide baseline values for further studies. In addition, the results show that BeWo cell morphology has marked similarities to that reported for human trophoblast, making it a useful model for subsequent in vitro studies.