Abstract: The method of culturing cells disclosed herein includes printing cells onto a substrate that includes cell adhesive regions and cell repulsive regions. The cells are suspended in a printing medium to create a cell suspension, and a volume of the cell suspension is loaded into a printer. A cell adhesive region of the substrate is aligned beneath the printing channel of the printer, and droplets of the cell suspension are dispensed from the printing channel directly onto the cell adhesive region. Contact of the dispensed droplets with cell repulsive regions of the substrate is limited, either by targeting of the droplets to the cell adhesive regions, by repulsions generated by the cell repulsive areas, or both. The cells adhere to the cell adhesive regions to create a cell pattern, and are maintained thereafter in a physiologically suitable environment.

Abstract: A pumpless microfluidic system is disclosed that can be used to mimic the interaction of organ systems with the immune system. Also disclosed is a method for mimicking an immune system, comprising culturing a plurality of organ cells and at least one population of immune cells in the disclosed pumpless microfluidic system under physiological conditions. The method can further comprise activating an immune reaction in the pumpless microfluidic system, continuing the culture for a defined period, collecting a sample of culture medium from the system, and assaying the sample for one or more indicators of an immune response.