In Part 1 of the Structure of the Skin, the basic foundation of the skin was discussed. Now the focus will shift to the specialized cells that give the skin its unique capabilities to multitask.
Langerhans cells are found in the epidermis and are thought to be a type of immune cell that may function somewhat like a watchman. It is looking for outside pathogens and informs the immune system in case a reaction needs to be mounted.
Merkel cells are found at the base of the epidermis and have a close connection to the nervous system. They are thought to play a role in sensation to sense touch.
Fibroblasts are found in the dermis and responsible for producing connective tissue and assisting in healing after injury to the skin.
Capillaries are found through the dermis to provide blood flow and nourish the skin. Lymphatic vessels are also found that remove waste and excess fluid. When our cheeks look flush with redness, this is because the capillaries have vasodilated and give an overall red appearance to the skin.
Each of these cells has the ability to misbehave and form different types of skin cancer as well. Merkel cells in particular can form an aggressive type of skin cancer called Merkel Cell Carcinoma. This will be discussed in a later post.
It is interesting to note that collagen is found in the dermis, below the epidermis. Although some products will boast about collagen as an ingredient, it is not necessarily true that collagen can be applied superficially to the skin and find its way into the dermis. Although there may be some overall improvement in the appearance of the skin, this is likely from excess hydration in the superficial layers of skin from the product.
The next post will focus on the specialized structures of the skin such as oil glands and sweat glands.