The single-analyte FluoroSpot assay provides an ELISpot alternative with fluorescent detection instead of enzymatic. The assay enables enumeration of cells secreting human Interleukin-10 (IL-10). FluoroSpotBASIC (550) contains monoclonal capture and detection antibodies, a secondary fluorophore-conjugated detection reagent (SA-550) and a Fluorescence enhancer.