Transforming growth factor-β activation in cell-free extracellular matrix preparations. Commentary

Transforming growth factor-β (TGF-β) is an important regulator of many cellular and immunological functions. It is often deposited in extracellular matrices in a latent form. This commentary is to draw attention to the likelihood that preparing cell-free matrices from tissue cultures by high pH buffers, such as ammonium hydroxide, can activate the TGF-β. Therefore, cells subsequently seeded onto such matrices may respond to the presence of active TGF-β in addition to interactions with macromolecular extracellular matrix components.