High-throughput single-cell antibody secretion quantification and enrichment using droplet microfluidics-based FRET assay
Justina Rutkauskaite,
Simon Berger,
Stavros Stavrakis,
Oliver Dressler,
John Heyman,
Xavier Casadevall i Solvas,
Andrew deMello,
Linas Mazutis
Affiliations
Justina Rutkauskaite
Institute of Biotechnology, Life Sciences Centre, Vilnius University, 7 Sauletekio ave., 10257 Vilnius, Lithuania; Institute for Chemical and Bioengineering, ETH Zurich, Vladimir Prelog Weg 1, 8093 Zürich, Switzerland
Simon Berger
Institute for Chemical and Bioengineering, ETH Zurich, Vladimir Prelog Weg 1, 8093 Zürich, Switzerland
Stavros Stavrakis
Institute for Chemical and Bioengineering, ETH Zurich, Vladimir Prelog Weg 1, 8093 Zürich, Switzerland
Oliver Dressler
Institute for Chemical and Bioengineering, ETH Zurich, Vladimir Prelog Weg 1, 8093 Zürich, Switzerland
John Heyman
Harvard University, SEAS, 9 Oxford St., Cambridge, MA 02139, USA
Xavier Casadevall i Solvas
MeBioS division, Department of Biosystems, KU Leuven, Willem de Croylaan 42, 3001 Leuven, Belgium
Andrew deMello
Institute for Chemical and Bioengineering, ETH Zurich, Vladimir Prelog Weg 1, 8093 Zürich, Switzerland; Corresponding author
Linas Mazutis
Institute of Biotechnology, Life Sciences Centre, Vilnius University, 7 Sauletekio ave., 10257 Vilnius, Lithuania; Corresponding author
Summary: High-throughput screening and enrichment of antibody-producing cells have many important applications. Herein, we present a droplet microfluidic approach for high-throughput screening and sorting of antibody-secreting cells using a Förster resonance electron transfer (FRET)-based assay. The FRET signal is mediated by the specific binding of the secreted antibody to two fluorescently labeled probes supplied within a droplet. Functional hybridoma cells expressing either membrane-bound or secreted monoclonal antibodies (mAbs), or both, were efficiently differentiated in less than 30 min. The antibody secretion rate by individual hybridoma cells was recorded in the range of 14,000 Abs/min, while the density of membrane-bound fraction was approximately 100 Abs/μm2. Combining the FRET assay with droplet-based single-cell sorting, an 800-fold enrichment of antigen-specific cells was achieved after one round of sorting. The presented system overcomes several key limitations observed in conventional FACS-based screening methods and should be applicable to assaying various other secreted proteins.
