Recent headlines tell us that the average American lives in a household of 2.62 people, chows down too many potato chips, and thinks that the “Dirty Dancing” remake is a bad idea. But averaging over populations obscures the often highly variable characteristics of individuals, and the same is true for cells. To get a better idea of what’s going on inside individual cells, a talented team of Canadian researchers developed a high-throughput microfluidic device for analyzing mRNA and miRNA expression in single cells.
The device is a one-stop shop for all steps of single-cell processing: cell capture, lysis, reverse transcription, and quantitative PCR. The high-throughput device can perform 300 parallel qRT-PCR assays of single cells in nanoliter volumes. When the researchers put the device to the test by analyzing mRNA and miRNA expression in several cell types, they found that:
- the microfluidic device has a dynamic range of at least 104 for cell copy number, measurement precision greater than 10%, and single-molecule sensitivity
- miR-16 expression was tightly regulated in K562 cells, whereas miR-223 expression was highly variable among cells
- miR-145 and its target transcript, OCT4, are coregulated during differentiation in hESCs
- the device could detect an mRNA single-nucleotide variant in a primary tumor sample
The researchers predict that the device will be useful for a variety of applications, such as stratifying cell populations with mixed differentiation states and diagnosing disease at the single-cell level.
Learn more about the secret lives of single cells at PNAS, August 2011.