QUANTIFICATION OF COLLAGEN FIBRE MATURITY IN DECELLULARIZED COLLAGEN MATRICES
Main Article Content
Keywords
Transplantation, Collagen, Decellularization.
Abstract
Bioengineering of tissue for transplantation is a growing area. As technology improves it is becoming increasingly possible to produce new cells, tissues and organs to replace damaged or diseased ones. Growing tissues alleviates the reliance on compatible donors and producing immunologically compatible material is possible. Growing new tissues involves the seeding of a supporting structure, or scaffold, with cells taken from the recipient. The scaffold needs to be made of an inert material that doesn’t initiate an immune response, it must have the structure and mechanical properties of the tissue that it is replacing and lastly it must provide an environment that is conducive to cell proliferation. Collagen has emerged as the scaffold material of choice for several reasons: few people possess humoral immunity against it, it is one of the most abundant proteins on earth and, as it is found in many tissues, it can provide a three dimensional structure of the correct spatial arrangement. Preparation of the collagen scaffold involves removal of the cellular content of the tissue leaving behind the extracellular matrix. This is achieved by decellularization using chemical, physical or biological reagents. The decellularization process must remove any material that could illicit a immune response, yet not damage the collagen content or structure. Certain dyes can be used to selectively stain collagen and one of these, picrosirius red, was used here to identify the collagen and study its structure. Samples of three potential scaffolds: tendon, aorta and carotid artery, were examined before and after decellularization to see how the process had affected the amount and structure of the collagen present. It was found that the decellularization process had little effect on the collagen of the tendon or carotid artery, but the aortic collagen was altered by the treatment.
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