Gene expression profile of Th1 and Th2 cytokines and their receptors in human and nonhuman primates.

BACKGROUND

To date comparative knowledge concerning gene expression profiles of T-helper 1(Th1)/Th2 cytokines and their receptors between human and non-human primates is scarce.

METHODS

We assessed the gene expression level of both Th1 [interleukin-4(IL-4)] and Th2 [IL-12, interferon-gamma(IFN-gamma)] cytokines and the receptors (IL-4Ralpha, IFN-gammaR1, IFN-gammaR2) in peripheral blood mononuclear cells (PBMC) from humans, chimpanzee, baboon, and macaque by a quantitative real-time reverse transcriptase-polymerase chain reaction(RT-PCR).

RESULTS

The expression level of the IFN-gamma gene was markedly lower in humans than that in non-human primates. The IL-4 gene expression was significantly higher, whereas that of IL-12 was distinctly lower, in human/chimpanzee than in baboon/macaque. The IFN-gammaR2 gene expression was especially higher in the macaque than in the other three primates.

CONCLUSIONS

These results indicate distinct gene expression of Th1/Th2 cytokines and their receptors in primates. These also suggest characteristic differences in Th1/Th2 immune responses affecting host defense and/or disease susceptibility among these primates.