Immunoassays: ELISPOT and FluoroSpot
ELISpot and FluoroSpot are highly sensitive immunoassays that use sandwich enzyme-linked immunosorbent assay (ELISA)-based technology to measure the frequency of cells that secrete soluble targets at the single-cell level. The technique is suitable for secreted proteins, such as cytokines, where single-cell analysis is of interest. These assays are ideal in immuno-oncology research for identifying specific tumor antigens, and to quantify antigen-specific effector cells. The limit of detection typically achieved can be 1 in 100,000 cells. The high sensitivity of the assay makes it particularly valuable to measure the cell-mediated immune response where low frequency cells typically occur.
The FluoroSpot assay utilizes fluorochrome-conjugated detection antibodies, allowing the simultaneous detection of several analytes and subsequent T-cell sub-population analysis. The detection is made possible by using a biotinylated detection antibody for one analyte, and tag-labeled detection antibodies for the other analyte(s). The resulting spots are analyzed in an automated reader, as e.g., Mabtech IRISTM.
Ex Vivo Oncology Assays
Our oncology center of excellence in Ann Arbor, Michigan frequently uses these assays ex vivo for discovery oncology work.