Enhancement of serum fibronectin adsorption and the clonal plating efficiencies of Swiss mouse 3T3 fibroblast and MM14 mouse myoblast cells on polymer substrates modified by radiofrequency plasma deposition

Abstract

Surfaces which specifically enhance fibronectin (FN) adsorption from serum containing media were prepared and investigated. Since FN adsorbed to a substrate from serum facilitates the spreading and subsequent replication of anchorage-dependent cells in culture, these new surfaces were of interest. The surfaces studied were prepared by treating either poly(ethyleneterephthalate) (PET) or polystyrene (PS) with a radiofrequency plasma discharge of ethylene oxide (C 2H 4O) or perfluoropropane (C 3F 8) vapor, a mixture of the two, or one of the following vapors: acetone, air, methanol, or water. The surfaces were analyzed by electron spectroscopy for chemical analysis (ESCA). Identification and quantitation of surface functional groups was done by high resolution ESCA. FN adsorption from a series of serum dilutions to modified plastic surfaces was measured using Iodine ( 125I)-labeled FN. Swiss mouse 3T3 fibroblasts and MM14 mouse skeletal myoblasts were each plated onto these surfaces, as well as on two different types of commercially available culture dishes. Plating efficiency was measured on each surface. 3T3 cell spreading after 2 h, spreading kinetics, and attachment kinetics were also studied on some surfaces. All PET and PS plasma-treated surfaces except those treated with C 3F 8 adsorbed more FN than did three commercially available culture surfaces. FN adsorption was maximal at intermediate serum concentration on all surfaces. The greatest enhancement in FN adsorption occurred on the acetone plasma-treated surface. Bovine serum albumin adsorption from serum to the acetone plasma-treated surface was less than that to the untreated surface. The plating efficiencies of both 3T3 and MM14 cell types correlated well with FN adsorption to the plasma-treated surfaces, but the cell behavior on the commercial tissue culture dishes did not always follow this trend. In general, surfaces exhibiting both high plating efficiencies and high FN adsorption had a greater fraction of surface C-O functionalities than did low plating efficiency, low FN adsorption substrates. The possible role of FN as well as other serum spreading factors in mediating enhanced cell growth is discussed.