Compositions having a combination of specific biological components have been found to exert a number of useful effects in mammalian cells, including modulating TGF-.beta.; signaling, apoptosis, and proliferation of mammalian cells, as well as decreasing inflammation in mice. These components can be obtained commercially, or can be prepared from biological tissues such as placental tissues. Placental amniotic membrane (AM) preparations described herein include AM pieces, AM extracts, AM jelly, AM stroma, and mixtures of these compositions with additional components. The compositions can be used to treat various diseases, such as wound healing, inflammation and angiogenesis-related diseases.