Detecting cytokine production at the single-cell level.

Cytokines are versatile mediators of intercellular communication. Their functional diversity has aroused considerable interest and prompted the rapid development of a number of techniques for their detection and measurement. However, conventional cytokine assays measure only their bulk release by large numbers of cells and give no indication of the identity or frequency of producer cells. Here, the advantages and disadvantages of a relatively new approach to detect cytokine production by single cells are reviewed.