Regenerative medicine in skin repair
The ability to repair extensive continuous solutions of the skin has always been a problem of vital importance in medicine, because the loss of integrity of the organ deputy to the protection from external insults exposes the body to a huge range of risk of loss of homeostasis, as well as the aggressive part of microorganisms. The solutions of continuous skin are, therefore, protected with allogeneic skin from cadaver donor or autologous with constructs obtained by processes of cell expansion.
For the preparation of the cell culture, it is necessary a sample of tissue from patient or donor. The sampling is performed on a flat body area, avoiding the articular surfaces, the face and hands. The sample of burned patients is preferably carried out by the second day after admission the patient. Following disinfection protocols and transportation of the tissue sample, the biopsy is machined and with the use of enzymes, are separated cells of the dermis and epidermis.
One proceeds to the cultivation in defined medium, the cell growth in special incubators and, after about 3 weeks, the cells are seeded on special supports (“scaffold” or “foils”) used to convey the cells in the lesion. They, in fact, can be placed directly on the area to be treated or cryogenically preserved in special containers to be used at a later time as needed. From the surgical point of view, the main advantage of growing epithelial is that a large area of skin substitute can be produced to cover areas bloody: a fragment biopsy of 2 cm2 can be made to expand up to a surface 10,000 times greater in 3-4 weeks.
Currently, the processing of skin cells is performed for the preparation of:
- Keratinocytes foils 10×10 cm for autologous use
- Keratinocytes foils 10×10 cm for homologous use
- Fibroblasts Foils 8×8 cm for autologous use
- Fibroblasts Foils 8×8 cm for homologous use
The term Epidermolysis bullosa (EB) refers to a heterogeneous group of diseases, mostly hereditary, whose common feature is a particular susceptibility of the integuments to the clutch, with formation of bullous lesions following trauma also of small entity. There are different clinical forms of the disease, some of them very slight, and other serious that can be fatal in neonatal or even in the womb. The symptoms occur during the first months of life in newborns. The overall prevalence of EB simple, junctional EB and dystrophic EB in the population was estimated at 1/130.000 in the United States, 1/100.000 in Italy.
At the level of cutaneous widely throughout the body, but especially in locations most exposed to friction, bullous lesions are present, often ulcerated with loss of skin appendages, sometimes scarring alopecia. The bullous lesions occur also borne by the mucosa of the gastrointestinal system, then the oral mucosa, esophageal mucosa, with consequent cicatricial stenosis, anal mucosa. These findings then lead to a framework of malnutrition, and subsequent growth retardation, resulting in pain in feeding and defecation. In more severe cases there is involvement of the mucosa with the development of ocular keratitis, lesions of the respiratory tract, anemia.
The current treatment of the disease is a symptomatic treatment, not a cure of the disease as a correction of incorrect genes is currently not available
Recurrence is the dominant feature of this disease, so that the results are divided into short when it occurs before two years, good between 2 and 4 years and excellent when you are able to exceed 4 years. In fact, the concept of recurrence is difficult to define as a decline in the 5th finger is perfectly compatible with the functionality of the hand as a restriction of 1 space limits roughly use.