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
1
 Encapsulate individual cells in CelBioGel ™ Encapsulation Matrix using the CellSys 100™ Microdrop Maker.
2
 Diffuse the biotinylated capture antibody into the GMDs. Streptavidin forms a bridge between the biotinylated encapsulation matrix and the biotinylated capture antibody.
3
 Incubate the GMDs to allow the capture and retention of secreted protein within the agarose matrix. Label captured protein using fluorescently labeled reporter antibodies.
4
 Identify and/or isolate secreting cells based on fluorescence intensity. GMD technology is compatible with fluorescence microscopy and flow cytometry methods.

 
 




 
  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
1
 Enrich for stable, high producing clones in less than one day.
2
 Isolate rare cells that occur at a frequency as low as 0.01%.
3
Eliminate time-consuming and laborious Limiting Dilution Cloning.
4
 Improve yields and increase productivity.
5
 Reduce development time and costs.

 
  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)
Secretion Assay Products & Services
Screening Service Gel Microdrop Secretion Assay
Secretion Assay Commercial Lease Form
Secretion Assay Research Lease Form
Secretion Assay Non Profit Lease Form