Where does cross-linking of collagen occur?
cornea
Cross-linking of collagen refers to the ability of collagen fibrils to form strong chemical bonds with adjacent fibrils. In the cornea, collagen cross-linking occurs naturally with aging due to an oxidative deamination reaction that takes place within the end chains of the collagen.
Where can collagen fibers be found?
Collagen consists of amino acids bound together to form a triple helix of elongated fibril known as a collagen helix. It is mostly found in connective tissue such as cartilage, bones, tendons, ligaments, and skin.
What is cross-linking of collagen fibers?
The formation of collagen cross-links is attributable to the presence of two aldehyde-containing amino acids which react with other amino acids in collagen to generate difunctional, trifunctional, and tetrafunctional cross-links. Once this condition is met, cross-linking occurs in a spontaneous, progressive fashion.
Where is Tropocollagen found?
Tissues. The formation of tropocollagen begins in the nucleus of a fibroblast, when a messenger RNA (mRNA) molecule is formed on a stretch of DNA (a collagen gene) through the process of transcription.
What is cross-linking in immunology?
Crosslinking is the process of chemically joining two or more molecules by a covalent bond. Crosslinking reagents are used in a variety of techniques to assist in determining partners and domains of protein interactions, three-dimensional structures of proteins, and molecular associations in cell membranes.
What is cross-linking in polymers?
Put simply, crosslinking involves a chemical reaction between polymer chains to link them together. Crosslinking can influence several end properties across most applications, including: Coating chemical resistance. Polymer flow properties – block and print resistance. Coating toughness.
Where is collagen most commonly found?
Collagen is the most abundant protein in the human body, found in the bones, muscles, skin, and tendons. It is the substance that holds the body together. Collagen forms a scaffold to provide strength and structure.
What is an example of collagen fibers?
Collagen is a type of protein fiber found abundantly throughout our body. It provides strength and cushioning to many different areas of the body, including the skin. More specifically, collagen is found in our various types of connective tissues such as cartilage, tendons, bones, and ligaments.
How are collagen fibers stabilized and cross-linked?
Collagen fibrils are strengthened and stabilized mainly by covalent cross-links, existing both within and between individual tropocollagen molecules. These crosslinks represent the enzyme-catalyzed formation of covalent bonds involving lysine and hydroxylysine side chains.
Where are fibroblasts found?
A fibroblast is a specific type of connective tissue cell that is found in skin and tendons and other tough tissues in the body. It secretes collagen.
What is the history of corneal collagen cross-linking?
The bases for the currently employed corneal collagen cross-linking techniques were developed in Europe by researchers at the University of Dresden in the late 1990s. UV light was used to induce collagen cross-linking in riboflavin soaked porcine and rabbit corneas via the oxidation pathway.
Can uvuv light induce collagen cross-linking in corneas?
UV light was used to induce collagen cross-linking in riboflavin soaked porcine and rabbit corneas via the oxidation pathway. The resultant corneas were shown to be stiffer and more resistant to enzymatic digestion. The investigation also proved that treated corneas contained higher molecular weight polymers of collagen due to fibril crosslinking.
What is the primary purpose of cross-linking?
The primary purpose of cross-linking is to halt the progression of ectasia. Likewise, the best candidate for this therapy is an individual with a progressive ectatic disease of the cornea. The most common indication is keratoconus.
What is the effect of crosslinking on corneal epithelium?
Crosslinking effect are seen more in the anterior cornea, as riboflavin concentration reduces with increasing depth. IOP measurements are not affected significantly post CXL. The debrided epithelium is replaced in 3-4 days. Limbal stem cells are not damaged by CXL, as riboflavin is kept away by the remaining peripheral epithelium.