Abstract: A microscale bioreactor system for and method is disclosed for providing improved cell culture growth conditions in a small-volume vessel. For example, a microbioreactor system is provided that may include a small-volume vessel and wherein the small-volume vessel may include a field of actuatable surface-attached microposts. Further, the microbioreactor system may include an actuation mechanism for actuating the surface-attached microposts into movement. In some embodiments, the surface-attached microposts may be functionalized with, for example, activation signals for converting standard T-cells in a growth media to activated T-cells. Further, a method of using the microbioreactor system for providing cell culture growth conditions including enhanced oxygenation and nutrients distribution in a small-volume vessel is provided.