Modulation of in vitro myogenesis induced by different polymer substrates

The understanding of substrate dependence of cellular differentiation is im portant in the surface design of biocompatible artificial devices as well a s cell-incorporated tissue engineered devices. In an attempt to understand some of the genetic and epigenetic aspects of the control of cell different iation in the presence of two different materials, Chronoflex (CH) and plas ma treated Chronoflex coated with Hyaluronan (CH-HA), we used primary cultu res of human myogenic cells, a model that encompasses cell proliferation, m igration, fusion, and differentiation dependent gene activation. By testing both the material samples on the growth of human myoblasts in primary cult ures, we demonstrated that both CH and CH-HA substrates were able to suppor t the cell growth since they did not affect cell count and DNA synthesis. O n the contrary, the degree of myoblast differentiation, assessed as a funct ion of creatine phosphokinase (CPK) activity on living cells, was completel y different on the two biomaterials. Indeed, the amount of CPK increased on CH-HA cultured cells as a result of myotube formation, while CH grown myob lasts remained unfused and displayed no increase on the CPK activity even a fter 12 days culture. Moreover, the expression level of MyoD and myogenin m RNA, both related to myogenic cell differentiation, appeared extremely low in CH-grown cells, while they were rapidly induced in CH-HA cultured myobla sts. (C) 1999 Kluwer Academic Publishers.