Thermally responsive polymer-grafted surfaces facilitate patterned cell seeding and co-culture

Tissue engineering constructs that effectively duplicate natural tissue function must also maintain tissue architectural and organization features, particularly the integration of multiple cell types preserving distinct, integrated phenotypes. Cell–cell communication and biochemical cross-talk have been shown to be essential for the maintenance of differentiated cell functions in tissues and organs. Current limitations of cell-culture hinder progress in understanding the features and dynamics of heterotypic cell communication pathways critical to developing more sophisticated or effective tissue-engineered devices. We describe a method to conveniently electron-beam pattern cell culture surfaces with thermo-responsive polymer chemistry that exploits changes in cell-polymer adhesive interactions over a temperature window amenable for high-throughput cell culture. Cells seeded on these patterned surfaces at 20°C adhere only to surface areas lacking thermo-responsive grafting chemistry: grafted domains at 20°C are hydrophilic and non-cell adhesive. The culture temperature is then increased to 37°C, collapsing the hydrated grafted chemistry. A second cell type is added to the culture and adheres only to these exposed relatively hydrophobic grafted patterns. Both cell types can then be effectively co-cultured at 37°C under multiple conditions. Long-term cell pattern fidelity and differentiated cell functions characteristic of each co-planar cell type are observed. This method is simple and has few limitations, compared with other existing co-culture methods.