Abstract
In our first paper histochemical and scanning electron microscopic features of human mesothelial cells in vitro were discussed. This paper is concerned with the temporal change of lineage-directed antibodies, including those to keratins, vimentin, epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA) in cultured mesothelial cells.
1. In the early stages of culture the prominentlyproliferating cells stained for low (40, 45 kdaltons) molecular weight keratins said to be the main mesothelial proteins, but were negative for high (65 kdaltons) molecular weight keratin and EMA. After several weeks in reaching confluence, both types of keratin were expressed together with EMA by many cultured cells.
2. From the beginning of culture antisera to vimentin always reacted with the proliferating cells.
3. Throughout culture, none of the cultured cells showed immunoreactivity for CEA.
Our results show that cultured mesothelial cells expressed non-epithelial markers (vimentin) in the early stages of culture. On the other hand, in the course of culture, coexpression of non-epithelial and epithelial (EMA and high molecular weight keratins) markers was observed similar to the morphologically bi-phagic pattern, reported in the previous paper.
