PODS®, the longer-lasting growth factor
![PODS®, the longer-lasting growth factor](http://cellgs.e2ecdn.co.uk/ArticleImages/PODS2.jpg?w=755&h=500&mode=pad&quality=85)
Growth factors (GFs), which include cytokines, are rather unstable proteins with half-lives sometimes as short as a few minutes. This instability is an important part of their function. Imagine GFs that persisted for months in-vivo: they would be widely diffused and their ability to define tissues would be lost.