Quantification of cytokine transcripts using polymerase chain reaction.

Quantitative PCR techniques are both attractive and daunting. Most users appreciate the need for accurate quantification, but achieving this is not always straightforward. It usually requires more technical equipment than classical PCR and common sense controls are no longer sufficient to generate confidence in the quantitative power of the assay. This review describes the principles that underlie the most commonly used quantitative PCR techniques and their different read-outs, and aims to provide the reader with the tools needed to discriminate between the different published techniques.