Large-scale investigation of the olfactory receptor space using a microfluidic microwell array

Area of Science:

• Neuroscience
• Cell Biology
• Biotechnology

Background:

• Mammalian olfactory systems detect numerous odorants using a vast array of odorant receptors (ORs).
• Each olfactory sensory neuron (OSN) expresses a single OR type, creating a complex system for odor discrimination.
• Analyzing odorant responses across all OR-OSN types is challenging due to the large repertoire and difficulties with heterologous expression.

Purpose of the Study:

• To develop a high-throughput screening method for analyzing odorant responses in single olfactory sensory neurons (OSNs).
• To overcome limitations in studying the large repertoire of odorant receptor (OR) types and their associated OSNs.
• To enable the characterization of rare and broadly responsive OSN populations.

Main Methods:

• Development of a microfluidic screening platform utilizing microwells for simultaneous single-cell analysis.
• Application of calcium imaging to detect and analyze odorant-evoked responses in large numbers of OSNs.
• Screening of over 20,000 single cells, enabling simultaneous analysis of approximately 2900 OSNs.

Main Results:

• Simultaneous screening and analysis of odorant responses from approximately 2900 OSNs.
• Successful detection of rare OSNs exhibiting specific odorant responses.
• Identification of OSN populations broadly responsive to odorants with unrelated chemical structures.

Conclusions:

• The developed microfluidic approach enables high-throughput screening of single-cell responses.
• This technique facilitates the characterization of olfactory sensory neuron (OSN) populations and rare cell behaviors.
• The method has broad applicability for screening large cell populations in toxicology, pharmacology, and cancer research.