Porcine T-helper and regulatory T cells exhibit versatile mRNA expression capabilities for cytokines and co-stimulatory molecules

► mRNA expression of CD3-stimulated porcine PBMC, CD4−, and CD4+ Th+ Treg cells. ► mRNA analysis by RT-qPCR of various cytokines and other immune-relevant molecules. ► Resting Th cells induce various cytokines (mainly IFN-γ) upon stimulation. ► Activated Th cells induce various cytokines (mainly IL-4+IL-17) upon stimulation. ► Tregs induce immunosuppressive cytokines and molecules (e.g. IL-10+IL-35). T-helper (TH) and regulatory T cells (Tregs) are important modulators of immune responses. Aim of this study was to analyse their expression potential for cytokines and other immune-relevant molecules. Therefore, porcine PBMC, CD4− cells, CD4+CD25− resting, CD4+CD25dim activated TH cells, and CD4+CD25high Tregs were analysed on their mRNA expression potential ex vivo or after in vitro stimulation with CD3 and IL-2 by RT-qPCR. In vitro stimulation led to an increased production of pro-inflammatory (IL-6, TNFα) and TH (IL-2, IL-4, IL-17, IFN-γ) cytokines and a diverse production of immunosuppressive cytokines (IL-10 and TGF-β) in PBMC, CD4−, and CD4+ cells. Resting and activated TH cells showed an increased expression of various immune-modulatory molecules indicating that porcine TH cells possess distinct immunological skills in order to react on the actual immune situation. In contrast, Tregs appear to fulfil mainly immunosuppressive functions characterized by increased production of IL-10, IL-35, CD40L, and CD25.