Microfluidic~systems for investigating host-microbe relationship*

The symbiosis between the bioluminescent bacterium,~\textit{Vibrio fisheri,}~and the Hawaiian bobtail squid,~\textit{Euprymna scolopes,}~has been widely studied, and this association~is used~as a model system for studying bacterial~colonization of~ciliated~host tissues. The recruitment of~\textit{Vibrio fisheri}~to a~specialized light organ in the nascent squid is facilitated by various chemosensing and mechanosensing events.~To decipher the effects of such environmental and host-derived sensors on bacterial physiology, we use specifically designed microfluidic channels to engineer chemical and mechanical fields~similar to those~observed in the light organ of the squid.~These~\textit{in vitro~}studies are aimed at~complementing ongoing \textit{in vivo}~studies in the~system squid-vibrio system. This approach enables~us, for the first time, to isolate the effect of mechanical and chemical cues on bacterial motility in this symbiosis~and to quantify the bacterial response to these cues.