Vitronectin (Vn) is an adhesive glycoprotein, synthesized by the liver, released in plasma and present in the extracellular matrix. Vn binds PAI-1. This complex fully activates PAI-1, unlike PAI-1 in solution, where it does not appear to be stable and inactive. Vn therefore seems to regulate the enzymatic specificity of PAI-1, by stabilizing it. Decreased Vn levels occur in DICs and liver disease (cirrhosis). Vn deposition is associated with atherosclerotic lesions.
All proteins are accompanied by product information sheets which describe proper storage conditions. In order that we may warrant product stability, it is imperative that these storage conditions be maintained at all times. By briefly centrifuging the samples in their original containers, complete recovery of the sample at the bottom of the tube will be accomplished. Never allow protein solutions to remain at room temperature for excessive periods of time. Elevated temperatures may enhance the rate of protein degradation. Avoid storing or maintaining dilute protein samples for a long period of time. In general, purified proteins are inherently more stable in concentrated form. Many proteins are «sticky» by nature. To avoid losing protein due to adsorption, extremely dilute protein samples should be prepared in buffers containing excipients such as bovine serum albumin, poly(ethylene glycol), or gelatin.
