Spatial regulation and surface chemistry control of monocyte/macrophage adhesion and foreign body giant cell formation by photochemically micropatterned surfaces

Along-standing goal of biomedical device development has been the generatio n of specific, desired host blood and tissue responses. An approach to meet ing this design criteria is precise surface modification that creates micro patterns of distinct physicochemical character to direct cell adhesion and behavior. For this study, poly(ethylene terephthalate) films were coated wi th poly(benzyl N,N-diethyldithiocarbamate-co-styrene) and sequentially expo sed to monomer solutions for photoirradiation. A photomask was placed over different regions to generate micropatterned surfaces with graft polymer st ripes of three distinct ionic characters. Human monocytes were cultured on these surfaces to ascertain whether adhesion and fusion of manocytes/macrop hages could be controlled. Nonionic polyacrylamide greatly inhibited adhesi on and induced clumping of the few monocytes that did adhere. Macrophage ad hesion and spreading led to high degrees of interleukin-13 induced foreign body giant cell formation on both the anionic poly(acrylic acid), sodium sa lt, and benzyl N,N-diethyldithiocarbamate portions of the culture surface. In spite of the highest observed levels of monocyte/macrophage adhesion on cationic poly(dimethylaminopropylacrylamide), methiodide, the adherent cell s were not competent to undergo fusion to form foreign body giant cells. Th ese results suggest that inflammatory cell responses may be spatially contr olled in a manner that may be ultimately exploited to improve the biocompat ibility of medical devices. (C) 1999 John Wiley & Sons, Inc.