Cell migration is a process by which the cells move from one location to another, playing an essential role in embryological development, repair and regeneration, immune response, and metastasis. Cells migrate in response to chemical or mechanical signals generated by specific organs or tissues. The overall mechanism includes three steps - polarization, protrusion, and release. Polarization involves the formation of a distinct cell front and rear, which determines the direction of movement.

The skin is divided into epidermis, dermis, and hypodermis, the skin's outermost, middle, and inner layers. The human epidermal layer regularly undergoes renewal, where old, dead cells are replaced by new cells. Epidermal stem cells or EpiSCs divide and differentiate to restore the lost cells. For the renewal process, some EpiSCs continuously self-renew. In contrast, few others differentiate into transit-amplifying cells, which later form prickle or spinous cells, followed by granular cells,...

Epidermal stem cells (EpiSCs) are mainly located at the basal layer of the epidermis. These cells repair minor injuries of the skin and replace dead skin cells. However, EpiSCs’ cannot heal severe wounds such as major burns or those from diabetes or hereditary disorders. In such cases, culturing the epidermal stem cells from the patient is possible and has yielded successful treatment options, such as laboratory-grown skin grafts. These grafts are synthesized using a patient’s own EpiSCs...

Regeneration and repair processes are critical in healing damages caused by injury, disease, and aging. In regeneration, the damaged tissue is entirely replaced with new growth that restores the original architecture and function. In contrast, tissue repair usually results in a fixed tissue architecture involving scar formation. Scars generally do not reestablish tissue function and may also exhibit structural abnormalities at the injury site.
Regeneration
All animals have varying degrees of...

Following injury, the integrity of the injured tissues must be reestablished. For example, in skin tissue, wound repair involves coordination among resident skin cells, blood mononuclear cells, extracellular matrix, growth factors, and cytokines to complete the healing cascade.
Formation of Blood Clot
In case of deep injuries, trauma to blood vessels results in blood loss. In the meantime, phospholipids released from the ruptured endothelial cellular membrane are converted into arachidonic...

Epithelial tissues are large sheets of cells covering all of the surfaces of the body. These surfaces can be internal or external, for example, skin, airways, the digestive tract, the urinary system, and the reproductive system. Hollow organs and body cavities that do not connect to the body's exterior, including blood vessels and serous membranes, are lined by epithelial tissue known as the endothelium.
Epithelial tissues provide the body's first line of protection from physical, chemical, and...