Glycosaminoglycans from different sources

Finally, posttranslational modification of chemokines is another level of complexity when trying to understand the effects of chemokines in vivo. Recruited leukocytes and the inflamed tissue are a rich source of different enzymes that alter the structure of chemokines, changing their interaction with receptors and glycosaminoglycans and modifying their actions. Proteolysis, glycosylation, citrullination, and nitration are examples of how chemokines can be modified (Mortier et al., 2012). For instance, CD26 (also known as dipeptidylpeptidase 4) is a protease that can remove the first two amino acids from a protein that possesses a proHne or alanine in the... 

Other glycosaminoglycans chemically related to hyaluronan, such as chondroitin sulfate, keratan sulfate and heparan sulfate have a much lower molecular weight and have significantly much more variety in the isomers. Such isomers variety is due to presence of sulfated groups, number and arrangement of which could vary significantly. Hyaluronan, isolated from a variety of sources, is always chemically identical, the only difference between the HA products is molecular weight. 

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