CYTOKINE secretion - assay or PCR?

[Dr Robin Barclay PhD]

The cheapest cytokine assays are bioassays - there are a number 
of cell lines which (i) need a particular cytokine or (ii) are 
sensitive to a particular cytokine.  If you have the time and are 
not "rolling in loot" as someone else put it - bioassay may be 
the optimal method.  Out of interest - how will you know which 
cells secreted the cytokines - are you starting with purified 
populations?