Metaplastic

Metaplastic refers to a change in cell type. Specifically, it describes the phenomenon where one mature differentiated cell type is replaced by another mature differentiated cell type. This transformation typically occurs in response to chronic irritation or injury, although the exact mechanisms are still being investigated. Metaplasia is generally considered an adaptive process, a way for the tissue to better withstand the adverse conditions. However, it is not a benign adaptation, as metaplastic epithelium is often more susceptible to becoming cancerous than the original cell type.

A common example of metaplasia is squamous metaplasia, where a glandular epithelium transforms into a squamous epithelium. This is frequently seen in the respiratory tract of smokers, where the normal ciliated pseudostratified columnar epithelium is replaced by stratified squamous epithelium. Another example is intestinal metaplasia, where the gastric mucosa changes to resemble intestinal epithelium, often found in individuals with Helicobacter pylori infection or chronic gastritis. While the metaplastic cells themselves are mature and functional, the change in cell type can disrupt the normal function of the organ. Monitoring and addressing the underlying cause of metaplasia are crucial to prevent further tissue damage and the potential development of malignancy.