[Mantova cell factory: a model for skin regeneration]. / Mantova cell-factory: un modello di rigenerazione cutanea.

Chronic wounds, including venous and arteriosclerotic leg ulcers, diabetic foot ulcers, decubitus and trauma-induced wounds, represent a major problem in our society. Because the incidence of chronic wounds is high, the socioeconomic impact is considerable. The problem increases as the average age of the population increases and so the research into wound healing is continuously on the move. The aim of our research was to develop an autologous skin substitute and to verify its efficacy in closing chronic ulcers that do not respond to the currently available wound-healing treatments (topical therapy, antibiotics, surgical cleansing, external compression). Keratinocytes were obtained from the patients' foreskins. All medical procedures were undertaken with the approval of the ethics committee and with the patient's consent. In our survey we evaluated the possibility to grow autologous keratinocytes both with the ''feeder-layer'' method and on a type I collagen substrate. Using the first method, we obtained a two-dimensional strip composed of a few layers of normally arranged keratinocytes; it was, however, very fragile and this may affect the efficacy in clinical use. When cells were grown on an appropriately treated type I collagen substrate, we obtained more layers of normally arranged keratinocytes which were also differentiated into basal, spinous, granular and keratin layers. In addition to keratinocyte reproduction, we obtained reproduction of melanocytes in the correct basal position. The new skin substitute provides a new treatment option for chronic wounds that are refractory to conventional therapies. Adequate cytohistological and immunohistochemical analysis to evaluate the cells' correct morphology and phenotype is important in this technique.

Tissue engineering: chondrocyte cultures on type I collagen support. Cytohistological and immunohistochemical study.

Cartilaginous tissue has limited capacity for regeneration after damage, since the natural repair process leads to the formation of fibrocartilaginous tissue which does not have the resistance and capability of deformation under load, typical of hyaline cartilage which covers the articular surfaces. The possibility of transplanting human chondrocytes for cartilage reconstruction has been demonstrated in orthopaedics. The scope of our study was to evaluate the possibility of cultivating and expanding human chondrocytes seeded on a pure equine type I collagen support. Human articular cartilaginous cells multiplied and grew on a type I collagen substrate with production of extracellular matrix. This chondrocyte culture showed a correct morphology and phenotype as shown by alcian-PAS staining to indicate the presence of mucopolysaccharides and by immunohistochemical methods to identify type II collagen. The use of scaffolds may lead to improvement in the surgical technique, by making it possible to hold the cells physically in the area to be repaired and by allowing optimum spatial adaptation inside injuries of all shapes.