Microfluidic devices for studies of primary cilium mediated cellular response to dynamic flow conditions

We present the first microfabricated microfluidic devices designed specifically for studies of primary cilium mediated cellular response to dynamic flow. The primary cilium functions as a mechano-sensor in renal tubular epithelium, sensing the extracellular fluid flow. Malfunction of cilia has been implicated in e.g. polycystic kidney disease and other pathological conditions. Bending of the primary cilium by fluid flow has been shown to give rise to an intracellular calcium signal, however little is known about the sensitivity to flow duration, magnitude and direction. This paper presents a novel method for studying cilia forming cells in asymmetric microfluidic environments. The microfluidic devices presented here were designed for a dynamic control of the local fluid flow on a cellular level, and thus, enables studies of cellular responses to an amplitude, frequency and direction controlled cilium movement.