text: Compound collagen-based scaffolds have been developed in an attempt to improve the function of these scaffolds for tissue engineering. An example of a compound collagen scaffold is the collagen-chitosan matrix. Chitosan is a polysaccharide that is chemically similar to cellulose. Unlike collagen, chitosan biodegrades relatively slowly. However, chitosan is not very biocompatible with fibroblasts. To improve the stability of scaffolds containing gelatin or collagen and the biocompatibility of chitosan  is made by crosslinking the two; they compensate for each other's shortcomings.
  Collagen-elastine membrane, collagen-glycosaminoglycane (C-GAG) matrix, cross-linked collagen matrix Integra and Terudermis are other examples of compound collagen scaffolds.
  Allogeneic cultured keratinocytes and fibroblasts in bovine collagen (Gintuit) is the first cell-based product made from allogeneic human cells and bovine collagen approved by the US Food and Drug Administration (FDA). It is an allogeneic cellularized scaffold product and was approved for medical use in the United States in March 2012.