What impact does glycosylation have on the protein?

Answer

Glycosylation is a critical quality to consider for proteins.  The amount and type of glycosylation has dramatic effect on the physical nature of the protein and its biological function.  In addition to amino acid sequence, glycosylation can affect the folding of proteins and their ability to aggregate with each other.  The different folding and aggregate structures then have a resultant effect on stability and solubility.  The function is also affected in many ways by glycosylation, including the pharmacodynamics and pharmacokinetics of antibodies.  Antibodies with lower glycoforms can be cleared faster leading to a lower physiological half life.  The binding of the protein to the target is also affected in how long and how tightly it will bind.  Antigenicity can be impacted by glycosylation where certain glycoforms can increase antigenicity.  Amount of glycosylation addition and complexity of the glycoform both impact the protein, and there is a wide range of effects glycosylation can have these various protein characteristics.  In many cases, differential glycosylation effects can impact therapeutic efficacy of a protein.