First Author | Yang Z | Year | 2012 |
Journal | J Biol Chem | Volume | 287 |
Issue | 13 | Pages | 9972-81 |
PubMed ID | 22294690 | Mgi Jnum | J:183278 |
Mgi Id | MGI:5318161 | Doi | 10.1074/jbc.M111.288498 |
Citation | Yang Z, et al. (2012) Mutated major histocompatibility complex class II transactivator up-regulates interleukin-33-dependent differentiation of Th2 subset through Nod2 binding for NLR (NOD-like receptor) signaling initiation. J Biol Chem 287(13):9972-81 |
abstractText | Dominant-negative mutants of class II transactivator (mCIITAs) with N-terminal depletion have been used to repress the transcription of class II genes in xenotransplantation. Here, we report that mCIITA overexpressing myeloid cell line Ana-1 (Ana-1-mCIITA) derived from a C57BL/6 mouse was able to down-regulate the MHC class II expression and reverse immune responses from Th1 (IL-2(+)IFN-gamma(+)STAT4(+)) to Th2 (IL-4(+)IL-5(+)IL-10(+)IL-13(+)STAT6(+)) when cocultured with T cells. Mechanism analysis indicated that the mCIITA protein is able to initiate a NOD-like receptor-related signaling pathway via binding of the cytoplasmic Nod2 protein, which was followed by activating RIP2, caspase 1, and IKK-alpha/beta. This ensures the expression of the genes encoding the cytokines IL-33, IL-1beta, and TNF-alpha; however, only the highly expressed IL-33 is responsible for inducing the type 2 response, with a skewed Th2 cytokine secretion (IL-4(+)IL-5(+)IL-10(+)IL-13(+)IL-2(-)IFN-gamma(-)), which was completely prevented by the deactivation of the Nod2 gene with siRNA or by the blockage of the IL-33-related signaling using the mAb ST2L against the IL-33 receptor. mCIITA-mediated Th2 conversion was also successfully induced in vivo in a mCIITA-transgenic C57BL/6 mouse model. These results indicate that the Th1/Th2 balance could be regulated by an N terminus-depleted CIITA molecule via NOD-like receptor-related signaling, a property valuable for disease control, especially for inducing transplantation tolerance via the repression of class II expression and the attenuation of a Th1-dominant response. |