ELISpot

The enzyme-linked immunospot (ELISpot) assay is an extremely sensitive immunoassay used to detect and quantify protein-secreting cells. 

ELISpot is also very straightforward: cells are cultured and stimulated in a 96-well plate coated with capture antibody specific to the target protein. Cytokines, immunoglobulins, or other target proteins secreted by the cells are captured immediately upon secretion and throughout the stimulation process. Cells are removed and the secreted proteins are identified using a detection antibody. Detection reagents are added and visible spots form where each spot corresponds to an individual protein-secreting cell.