RNA extraction protocols. (A) Yield per million PBL blasts (open bars) and integrity (black bars) of RNA obtained with 5 extraction protocols. (B) PCR signals in cDNA synthesized from 200 ng total RNA of PBL blasts on high-abundance (green bars, β-actin), medium-abundance (red bars, TGF-β1), and low-abundance (blue bars, Foxp3) mRNA transcripts, following 5 RNA extraction protocols. (C) PCR signals for high-abundance (green bars, miR-155), medium-abundance (red bars, miR-142-5p), and low-abundance (blue bars, miR-223) microRNAs. Signals for TRIzol were set to 1. (D) Yield per million PBMC (open bars) and integrity (black bars) of RNA obtained with 5 extraction protocols. *P < .05. (E) PCR signals in cDNA synthesized from 200 ng total RNA of PBMC obtained directly from blood. *P < .05. #P < .01. **P < .001.