TNF and MIF transcription and secretion kinetics. PBMC from 2 donors were stimulated for 3, 9 or 18 hours (T3, T9 and T18 respectively) with LPS or SAC. TNF-α and MIF transcripts were quantified using CyProQuant-PCR and the corresponding secreted proteins were measured by ELISA. Transcript numbers are normalised for one million copies of β2-MG RNA relative to the level of transcripts in un-stimulated cells (fold increase). Secreted proteins are expressed as pg/mL for one million living cells.