Types Of Cells Found In The Skin
There are different types of cells found in the skin and most of them are found in the epidermis of the skin. The stem cells in the epidermis are located at the base of the epidermis and are glued by the hemidesmosomes to the basement membrane. There are three distinct types of cells found in the skin epidermis.
1. Keratinocyte
This is the most predominant of all types of cells found in the skin epidermis. It is located at the outmost part of the skin and constitutes about 90 percent of all types of cells found in the skin. Those that are located at the stratum basale (basal layer) are sometimes called basal karatinocytes or basal cells. The main duty of the keratinocytes is the prevention of water loss, UV radiation, heat, and the defense against attack pathogens like viruses, parasites, fungi, and bacteria. When pathogens start invading the epidermis, it prompts the reaction of keratinocytes as they provide proinflammatory mediators, particularly chemokines like CCL2 and CXCL10 which signals white blood cells to the pathogen invasion site.
2. Merkel cells
These types of cells found in the skin are receptors which can be easily attacked and form malignant tumors known as Merkel cell carcinomas. There have been proof that they originate from neural crest, and a recent study on vertebrates discovered that they have epithelial origins. These types of cells found in the skin can equally be found on some areas of the mucosa. They are also located at the stratum basale and are equally found in the rete ridges.
Merkel cells have often been regarded as APUD cells due to the fact that they are made up of dense core granules.
3. Melanocytes
These types of cells found in the skin are cells that produce melanin and they are found at the heart, the bones, the meninges, the inner ear, the unea, and the stratum basel (bottom layer) of the epidermis. Melanin is the substance that determines what color a skin will posses.
There are other types of cells found in the skin. Langerhans cells are cells that present antigen and are located on the mucosa and skin. They are always found in all the epidermis layers but are very rampant in the stratum spinosum. Langerhans can also be found in the blood vessels and the mucosa of the foreskin, mouth, and vagina. They can equally be seen in other associated tissues. When the skin is infected, it is the duty of the langerhan to be fully operational antigen-presenting cells.
Other types of cells found in the skin – Dermal Cells
The dermis of the skin equally has its own specialized cells which are presented below:
* Hair follicles: these are found in the dermis alongside the erector pilli muscle as they are glued to each other.
* The apocrine gland and Sebaceous glands glands are equally connected to the follicle.
* The eccrine (sweat) glands are also found in the dermis but are linked with the follicle
Other specialized nerve cells include vater-pacini and Meissner corpuscles which transmit the feeling of pressure and touch.
