title: Cell-based microfluidic platform for mimicking human olfactory system.
abstract: Various attempts have been made to mimic the human olfactory system using human olfactory receptors (hORs). In particular, OR-expressed cell-based odorant detection systems mimic the smell sensing mechanism of humans, as they exploit endogenous cellular signaling pathways. However, the majority of such cell-based studies have been performed in the liquid phase to maintain cell viability, and liquid odorants were used as detection targets. Here, we present a microfluidic device for the detection of gaseous odorants which more closely mimics the human olfactory system. Cells expressing hOR were cultured on a porous membrane. The membrane was then flipped over and placed between two compartments. The upper compartment is the gaseous part where gaseous odorants are supplied, while the lower compartment is the aqueous part where viable cells are maintained in the liquid medium. Using this simple microfluidic device, we were able to detect gaseous odorant molecules by a fluorescence signal. The fluorescence signal was generated by calcium influx resulting from the interaction between odorant molecules and the hOR. The system allowed detection of gaseous odorant molecules in real-time, and the findings showed that the fluorescence responses increased dose-dependently in the range of 0-2 ppm odorant. In addition, the system can discriminate among gaseous odorant molecules. This microfluidic system closely mimics the human olfactory system in the sense that the submerged cells detect gaseous odorants.
authors.affiliation: School of Chemical and Biological Engineering, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Seung Hwan
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Interdisciplinary Program of Bioengineering, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Eun Hae
authors.initials: EH
authors.lastname: Oh
authors.affiliation: School of Chemical and Biological Engineering, Seoul National University, Seoul 151-742, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul 151-742, Republic of Korea; Bio-MAX Institute, Seoul National University, Seoul 151-742, Republic of Korea; Advanced Institutes of Convergence Technology, Suwon, Gyeonggi-do 443-270, Republic of Korea. Electronic address: thpark@snu.ac.kr.
authors.forename: Tai Hyun
authors.initials: TH
authors.lastname: Park
mesh_terms: D001681:Biological Assay / Q000295:instrumentation*; D032701:Biomimetics / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017022:Flow Injection Analysis / Q000295:instrumentation; D005740:Gases / Q000032:analysis; D057809:HEK293 Cells; D006801:Humans; D056656:Lab-On-A-Chip Devices; D009812:Odorants / Q000032:analysis*; D018035:Receptors, Odorant / Q000032:analysis*; D012903:Smell / Q000187:drug effects / Q000502:physiology*; D046888:Tissue Array Analysis / Q000295:instrumentation*
chemical_list: D005740:Gases; D018035:Receptors, Odorant
keywords: Cell-based odorant detection system; Gaseous odorant; Microfluidics platform; Olfactory receptor