Epiteelisoluilla

Epiteelisoluilla is the Finnish term related to epithelial cells, the cells that form the epithelium, the protective and functional tissue that lines surfaces and cavities of the body and forms many glands. Epithelial cells cover external surfaces such as the skin and line internal passageways including the digestive, respiratory, and urinary tracts, as well as blood and lymphatic vessels in the form of endothelium.

Epithelial cells are characterized by polarity, with distinct apical and basolateral surfaces, and they sit on a basement membrane. They are connected by cell junctions such as tight junctions, adherens junctions, desmosomes, and gap junctions, which together regulate permeability and communication. Epithelia are classified by the number of cell layers (simple, stratified, pseudostratified) and by cell shape (squamous, cuboidal, columnar), with specialized forms such as transitional epithelium in the bladder.

Functions of epithelial cells include forming a protective barrier, regulating selective transport of ions and molecules, absorbing nutrients, and secreting substances through glands or as part of mucosal surfaces. Some epithelial cells are highly specialized, including goblet cells that produce mucus, ciliated cells that move mucus via ciliary action, and enterocytes with microvilli that increase surface area for absorption. Regeneration is rapid in many epithelia, driven by stem or progenitor cells in the basal layer.

Clinical relevance includes the prominence of carcinomas, cancers arising from epithelial cells, and the role of epithelial barrier dysfunction in inflammatory and infectious diseases. In research and medicine, epithelial cell models and organoids are used to study physiology, drug absorption, and pathophysiology. The term epiteelisoluilla may appear in Finnish scientific writing to denote phenomena occurring on or within epithelial cells.