FluoroSpot is the multiplex version of ELISpot. Just like in the ELISpot assay, target proteins secreted by cells are captured by specific antibodies immediately after secretion and throughout the stimulation process, making it an extremely sensitive assay. The difference to ELISpot lies in the mode of detection: where ELISpot relies on an enzymatic reaction, FluoroSpot utilizes fluorescence. This allows for multiplex analyses of several proteins simultaneously, enabling studies of cell populations with different functional profiles.