Prosthesis (i.e. – artificial body members) – parts thereof – or ai – Implantable prosthesis – Hair or skin
Patent
1997-10-22
2000-08-29
Yu, Mickey
Prosthesis (i.e., artificial body members), parts thereof, or ai
Implantable prosthesis
Hair or skin
623 66, 424422, A61F 210
Patent
active
061102083
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to: epidermis and dermal appendage, and containing as the support two biocompatible materials based on hyaluronic acid (HA) derivatives device, and as vehicling agent for preparing controlled release medicament.
BACKGROUND OF THE INVENTION
Skin loss due to trauma or disease is usually treated by the autograft technique, that is, by substituting the missing skin with pieces taken from donor areas of the same patient. An important step forward in the treatment of such lesions by reconstructive surgery is represented by in vitro cultures of keratinocytes (kc) (J. Rheinwald and H. Green, Cell, 6:331, 1975), whereby said cultures are allowed to expand in vitro, and membranes of epidermal cells are obtained which are potentially useful to cover skin wounds. This technique has been widely used in clinical practice, mainly for burn patients (G. G. Gallico et al., M. Engl.J. Med., 311-448, 1984), but problems arose right from the start, such as the difficulty for such grafts to take, the fragility of the epithelial sheets and consequent difficulty for the surgeon to handle them.
A different approach was adopted by Yannas et al. (Science, 215:174, 1982), who used resorbable porous materials constituted by coprecipitates of collagen and glycosaminoglycans (GAG), particularly chondroitin-6-sulphate, covered by a thin film of silicon membrane. The characteristic of such materials is that they present randomly formed, intercommunicating pores, rather like a sponge.
S. Boyce and J. Hansbrough (Surgery, 103-421, 1988) described growing kc on the surface of membranes made of collagen and GAG, reducing the surface porosity of the material. In order to limit the development of epidermal culture on the membrane surface, an additional, non-porous layer was inserted.
Skin graft technology must take into consideration the interaction between kc, the basal membrane and the underlying dermis. Nowadays it is generally thought that in the case of full-thickness lesions, autografts can be notably facilitated by placing a dermal bed in the wound underneath the epithelial layer.
The basal kc thus lie on a more physiological substrate and can develop a basal membrane and dermal-epidermal linking structures, capable of lending the necessary resistance to the graft.
Recent clinical studies have suggested that Cuono's method (Langdon et al. J. Invest. Dermatol. 91 5: 478, 1988), whereby a "full-thickness" wound is treated with an allograft from the skin of a cadaver, gives better results in terms of the percentage of graft which takes and general quality of the skin on healing.
However, grafts are difficult to obtain, expensive to store and are potential carriers of pathogenic viruses.
There is clearly a need for new, biodegradable, artificial skin substitutes which do not have these drawbacks, and satisfy the following requirements: cause inflammation or toxic phenomena when implanted in vivo; cell-polymer interactions, sufficient volume for the deposit of extracellular matrix and only slight, or no, migrational impediments during in vitro culture. longer requires it. Indeed, foreign bodies in vivo represent a high risk of infection and/or inflammation.
Indeed, the products already on the market or being developed present certain drawbacks: their degradation is uncontrollable and interferes with the wound healing process, thus favouring inflammation. Moreover, these substitutes require the epithelial cells to be thickly seeded on the support and left to proliferate for a long time.
Some examples of the products known to date and generally recommended for use in treatment of severe burns are: human fibroblasts are cultivated on a spongy, resorbable material constituted by polylactic, polyglycol or polygalactoside acid. Autologous kc are seeded onto these materials; heterologous human fibroblasts are cultivated on a collagen based substrate; human or pigs' skin, wherein the basal membrane and dermal matrix remain intact. The tissue is stored at a low temperature (-80.degree. C.) until
REFERENCES:
patent: 4485096 (1984-11-01), Bell
patent: 5326356 (1994-07-01), Della Valle et al.
patent: 5650164 (1997-07-01), Valle et al
patent: 5658331 (1997-08-01), Valle et al.
The New England Journal of Medicine, vol. 311, No. 7, pp. 448-451, Aug. 1984, "Permanent Coverage of Large Burn Wounds With Autologous Cultured Human Epitherlium", Gallico, III, M.D. et al.
Science, vol. 215, No. 8, pp. 174-176, Jan. 1982, "Wound Tissue Can Utilize a Polymeric Template to Synthesize a Functional Extension of Skin".
Surgery, vol. 103, No. 4, pp. 421-431, Apr. 1988, "Biologic Attachment, Growth, and Differentiation of Cultured Human Epidermal Keratinocytes on a Graftable Collagen and Chondroitin-6-Sulfate Substrate", Boyce, Ph.D., et al.
The Society for Investigative Dermatology, Inc., vol. 91, No. 5, pp. 478-485, Nov. 1988, "Reconstitution of Structure and Cell Function in Human Skin Grafts Derived From Cryopreserved Allogeneic Dermis and Autologous Cultured Keratinocytes", Langdon, M.D., et al.
Abstract, American Society for Aestheric Plastic Surgery, Inc., p. 80, Jan.-Mar. 1995.
The Journal of Cell Biology, vol. 113, No. 1, pp. 207-221, Apr. 1991, "Human Keratinocytes Express a New CD44 Core Protein (CD44E) as a Heparan-Sulfate Intrinsic Membrane Proteoglyca with Additional Exons", Brown et al.
The Journal of Cell Biology, vol. 111, No. 6, Pt. 1, pp. 2765-2774, Dec. 1990, "The Hyaluronate Receptor is a Member of the CD44 (H-CAM) Family of Cell Surface Glycoproteins", Culty et al.
Developmental Biology, vol. 155, 324-336, 1993, CD44 Positive Macrophages Take Up Hyaluronan During Lung Development Underhill et al.
The Society for Investigative Dermatology, Inc., vol. 101, No. 4, pp. 634-638, Oct. 1993, "Human Hair Follicle Germinative Epidermal Cell Culture", Reynolds et al.
Proc. Nat'l. Acad. Sci. USA, vol. 76, No. 11, pp. 5565-5669, Nov. 1979, "Growth of Cultured Human Epidermal Cells Into Multiple Epithelia Suitable for Grafing", Green et al.
Wounds, vol. 3, No. 3, pp. 116-126, May-Jun. 1991, "Human Keratinocytes Cultured on Membranes Composed of Benzyl of Hyaluronic Acid Suitable for Grafting", Andreassi et al.
The Journal of Investigative Dermatology, 81:74s-81s, 1983, "Keratinocytes Synthesized Basal-Lamina Proteins in Culture", Prunieras et al.
In Vitro Cellular & Developmental Biology, vol. 22, No. 12, pp. 695-705, Dec. 1986, "Keratinocytes Grown at the Air-Liquid Interface", Bernstam et al.
Cell, 6:331-344, Nov. 1975, "Serial Cultivation of Strains of Human Epidermal Karatinocytes: The Formation of Keratinizing Colonies From Single Cells", Rheinwald et al.
Abatangelo Giovanni
Callegaro Lanfranco
Soranzo Carlo
Fidia Advanced Biopolymers S.R.L
Nguyen Dinh X.
Yu Mickey
LandOfFree
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