Artificial Skin:
The skin generated in vitro is in fact the epidermis portion of skin only; when the epidermis is applied to the burnt part, this leads to the regeneration of dermis (remaining parts of skin) beneath. But improvements in the approach have allowed the reconstitution of virtually complete skin (both epidermis and dermis), called as living skin equivalent (LSE); this technology uses a collagen matrix as a support for development of the tissue. The skin explants used for attaining artificial skin may be either obtained from the patient concerned or from the foreskin (loose skin from the tip of penis) of newborn. Skin cells of new-borns grow more strongly than adult skin; the use of a synthetic polymer called as PGA helps the newborn skin to develop with no scars. Artificial skin from newborn skin explants is used to wrap the wound until the patient's skin is cultured and artificial skin is gained for grafting.
The production of artificial skin is following and this is particularly cell and not organ culture. The bulk (Ca 90%) of epidermis is constituted by cells that called keratinocytes which generated the dead cells (corneocytes) making up the outermost cornfield layers of skin. The keratinocytes are dissociated by treating the skin explants with trypsin. These cells are sophisticated in vessels the bottom of which is enclosed with irradiated 3T3 fibroblast cell line; this is because certain products from fibroblast cells facilitate the proliferation of keratinocytes. Keratinocytes develop to make colonies, which are again dissociated into single cells and cultured in the same manner. The process is repeated again and again till a confluent sheet of pure epithelium is completed; this sheet is detached from the culture vessels, cleaned and used for grafting. The explants for developing artificial skin for the graft might come from the patient himself to avoid rejection. A 3 cm2 skin explants may yield about 1.7 m2 artificial skin in 3-4 weeks representing a 5000-fold increase. In approximate 5 years after grafting of the artificial skin, all the essential components of skin are regenerated. Artificial skin grafts have been used to successfully repair several types of skin defects, including chronic skin ulcers.