Instability of extracellular matrix gene expression in primary cell culture of fibroblasts from human vocal fold lamina propria and tracheal scar

Primary fibroblast cell cultures were established from lamina propria of human vocal fold and tracheal scar. There exists a crucial need to provide new tools for studying voice biology, and one of the first steps is the development of a human primary laryngeal cell culture bank. Because cell lines can lose their differentiated phenotype in culture across passages, documentation of gene expression must be determined for passage populations, for us to have knowledge of cell behavior in vitro. Comparison of messenger RNA gene expression of extracellular matrix proteins (procollagen L collagenase, elastin, hyaluronic acid synthase 2. hyaluronidase, fibronectin, cd44, fibromodulin, and decorin) across cell passages (3, 4, 5, 6, 10, and 12 for normal lamina propria and 3, 4, 5, 6, and 10 for tracheal scar) revealed varied growth patterns. Cytogenetic analysis demonstrated relative stability of the karyotypes across passages for the tracheal scar cell cultures, whereas the karyotypes of the normal lamina propria fibroblasts showed instability in in vitro cultures. Recommendations for use of primary cell culture for further studies of gene expression are made.