ELISA on Attachment-Dependent or Suspension Grown Cells

Enzyme-linked immunosorbant assay (ELISA) has been a powerful technique in immunology since it was first developed in 1971 by Engvall and Perlman (1). The technique is based on the fact that proteins can be absorbed nearly irreversibly to plastic (2). The antigen (or antibody) is immobilized in the well of a 96-well plate. An enzyme-conjugated antibody (or antigen) is then added to the well to bind to a specific target. Any unbound antibody (antigen) is rinsed away. Substrate is added to react with the conjugated enzyme to allow a color reaction to occur. The intensity of the color is directly related to the amount of labeled antibody (antigen) bound to the target (3). This technique allows for specific and quantitative results. The assay is significant because it is straightforward and the materials readily available.