The modulation of PPAR1 and PPAR2 mRNA expression by ciglitazone in CD3/CD28-activated nave and memory CD4+ T cells

Abstract

Given their roles in immune regulation, the expression of the nuclear receptor peroxisome proliferator-activated receptor (PPAR) 1 and 2 isoforms was investigated in human nav̈e (CD45RA+) and memory (CD45RO+) CD4+ T cells. Stimulation of both types of cells via the CD3/CD28 pathway resulted in high expression of both PPAR receptors as measured by real-time PCR. Treatment with the PPAR agonist, ciglitazone, increased PPAR1 expression but decreased PPARγ2 expression in stimulated nave and memory cells. Furthermore, when present, the magnitude of both PPAR receptors expression was lower in nave cells, perhaps suggesting a lower regulatory control of these cells. Similar profiles of selected proinflammatory cytokines were expressed by the two cell types following stimulation. The induction of PPAR1 and suppression of PPARγ2 expressions in nave and memory CD4+ T cells in the presence of ciglitazone suggest that the PPAR subtypes may have different roles in the regulation of T-cell function. © 2012 Mohd Nor Norazmi et al.