What is the Epithelium?
The epithelium refers to one of the four types of animal tissue—the others are connective tissues, nervous tissues and muscle tissues. In addition to forming a number of glands, the epithelioid cells line the surfaces and cavities of structures throughout the entire body.
What are Epitheloid Cells?
Epithelioid cells are formations of cells that line the cavities in the human body. Epitheloid cells also cover flat surfaces on the body; of the four primary tissue types in the body, epithelioid cells are the most common.
The Epithelioid cells are bound together in sheets of human tissue known as the epithelia. These tissue sheets are tied together through a number of interactions, including adherens, gap junctions, tight junctions and desmosomes. The tight junction, which is deemed the tightest bond, is the only one found in the epithelium.
Functions of epitheloid cells include the following: selective absorption, protection, secretion, detection of sensations and trans-cellular transport.
How are Epitheloid Cells Classified?
Epitheloid tissues are classified by their composition; epithelioid cells are classified by the precise shapes of their cells. The four primary classes of simple epithelium cells are:
1.) simple squamous
2.) simple columnar
3.) simple cuboidal
The simple squamous epithelioid cells line areas where passive diffusion of gases take place. For example, these cells will be located in the linings of pericardial, the peritoneal cavities, the linings of the lungs and the walls of capillaries.
The simple cuboidal epithelioid cells typically possess absorptive, excretory and secretory functions. Examples of these cells include: salivary and pancreas glands, as well as the small collecting ducts of kidneys.
The simple columnar epithelioid cells are located in areas in possession of high secretive qualities (wall of the stomach) or absorptive qualities (small intestines). These types of epithelioid cells possess cellular extensions.
Lastly, the pseudostratified epithelia, also referred to as the called respiratory epithelium, are exclusively confined to the larger respiratory airways (the nasal cavity, bronchi and trachea etc.)
How are Epithelioid Cells Associated with Mesothelioma Cancer?
Epithelioid cells are connected to mesothelioma cancer, because transformations in the cells can, over time, form the deadly cancer. Epithelioid mesothelioma cancer is in fact the most common form of mesothelioma cancer—this particular disease accounts for approximately 70% of all mesothelioma cancer cases.
As stated above, the epithelioid cells are uniform in shape with unique tubular patterns and a cellular nucleus that, when evaluated under high magnification, is distinct from other nuclei. That being said, other types of cancers take similar form to epithelioid mesothelioma cancer.
Epithelioid mesothelioma cancer is a cancer that forms in the mesothelium, which is a protective layer of tissue that surrounds several vital organs. Epithelia cells, which are found throughout the human body, exist to separate several body environments. For instance, epithelial cells found in the skin separate the outside of the body from the inside.