A team of scientists of Wageningen University & Research, with cell biology, molecular biology and mathematics experts developed a microfluidic technique called receptomics that allows for the sequential exposure of samples against potentially hundreds of membrane receptors in parallel.
The receptor coding genes are printed in a grid layout of approximately one square centimetre onto a glass slide. A cell layer is seeded on top of the glass slide and the cells attach to the printed DNA. When the cells absorb the DNA via reverse transfection, a living cell array is formed where each spot of the array expresses an unique receptor.
Receptors (GPCR’s and ion channels) have many different biological functions in the human body like the detection of taste or scent molecules and hormones. These molecules are captured on the outside of the cell and they subsequently trigger a biological response inside of the cell. Those intracellular signals can be diverse but often involve calcium ions. Our receptomics technique visualizes the changes in calcium ion concentration within the cells of the entire living cell array. We visualize the real-time calcium signals of all array spots in parallel to determine specific response patterns for each sample. In that way we are able to capture for example taste differences in food stuffs like tomato, coffee or beer or hormone differences in blood serum.
A crucial tool in our receptomics technique is the software that allows for the rapid analysis of the signals and statistical tools to report receptor specific differences between samples.
We run receptomics projects focusing on tongue-on-a-chip, nose-on-a-chip and gut-on-a-chip applications. In the case of the gut-on-a-chip application the receptomics chip is placed downstream of gut cells to sense the hormones that are secreted from the gut cells upon stimulation.
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2. Henquet MGL, Roelse M, de Vos RCH, Schipper A, Polder G, Verhoeven HA, de Ruijter NCA, Jongsma MA (2016) Metabolomics meets functional assays: coupling LCMS and microfluidic cell-based receptor-ligand analyses. Metabolomics 12: 1-13 http://dx.doi.org/10.1007/s11306-016-1057-y
3. Srivastava S, Ramaneti R, Roelse M, Vrouwe EX, Brinkman A, de Smet LCPM, van Rijn C, Jongsma MA (2015) A generic microfluidic biosensor of G protein-coupled receptor activation – impedance measurements of reversible morphological changes of reverse transfected HEK293 cells on micro-electrodes. RSC Advances 5, 52563-52570. http://dx.doi.org/10.1039/C5RA04976H
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