The Gel Microdrop (GMD) Secretion Assay rapidly identifies cells that secrete a protein of interest. Viable, high-secreting or rare cells can be isolated and recovered using fluorescence activated cell sorting (FACS). Please click here for more information on the GMD Protein Secretion Assay and FACS.

  Encapsulated cells are analyzed or recovered using flow cytometry based on the amount of protein captured in each GMD. The capture and detection is analogous to the sandwich antibody format used in enzyme-linked immunosorbent assays (ELISA), however, the immunoreaction itself takes place within the agarose microsphere, leaving the encapsulated cell intact. A schematic representation of the GMD secretion assay is depicted below.


The GMD Secretion Assay Involves Four Easy Steps


  Protein secreted by an individual cell is captured and fluorescently labeled within the GMD. Unoccupied GMDs and GMDs occupied by non-secreting cells do not fluoresce. The fluorescence intensity of each occupied GMD corresponds to the amount of protein secreted by the cell. Fluorescing GMDs occupied by secreting cells can be sorted and recovered based on level of protein secretion.  

Advantages of the GMD Protein Secretion Assay

  We offer a lease program which includes a CellSys 100™ Microdrop Maker, CelMix™ and CelBioGel™ encapsulation reagents, training, and technical support. Alternatively, if you have a characterized cell line and two non-overlapping antibodies (one biotinylated and one fluorescently labeled), we will screen and sort your cells on a fee-for-service basis. Please contact us for details regarding either of these arrangements.  

Secretion Assay Forms And Additional Information (click on the PDF to view)