PGP and colitis: To further mimic the P-gp-overexpressing state of PBMC in colitis, human CCRF-CEM T-lymphocyte cells were transfected with P-gp via a lentiviral system, and the overexpression of P-gp was confirmed by flow cytometry assay (Fig. 8C) and qPCR assay, which demonstrated a 2.2-fold increase of protein expression (Fig. 8D) and a 20-fold increase of gene expression (Fig. 8E), respectively.