Tolerogenic dendritic cells generated by RelB silencing using shRNA prevent acute rejection.

It is well known that adoptive transfer of donor-derived tolerogenic dendritic cells (DCs) helps to induce immune tolerance. RelB, one of NF-κB subunits, is a critical element involved in DC maturation. In the present study, our results showed tolerogenic DCs could be acquired via silencing RelB using small interfering RNA. Compared with imDCs, the tolerogenic DCs had more potent ability to inhibit mixed lymphocyte reaction (MLR) and down-regulate Th1 cytokines and prompt the production of Th2 cytokines. They both mediated immune tolerance via the increased of T cell apoptosis and generation of regulatory T cells. Administration of donor-derived tolerogenic DCs significantly prevented the allograft rejection and prolonged the survival time in a murine heart transplantation model. Our results demonstrate donor-derived, RelB-shRNA induced tolerogenic DCs can significantly induce immune tolerance in vitro and in vivo.

Cedrol alleviates the apoptosis and inflammatory response of IL-1ß-treated chondrocytes by promoting miR-542-5p expression.

Cedrol has been shown to exert anti-tumor, anti-inflammatory, and anti-oxidative effects, but its role in osteoarthritis (OA) is unclear. This study aimed to explore the effect of cedrol in OA. Chondrocytes were isolated from newborn rats and cultured in Dulbecco's modified Eagle's medium (DMEM). Then, Alcian blue staining was used to identify the chondrocytes. IL-1ß and cedrol were used to treat chondrocytes. Cell viability and apoptosis were measured by MTT and flow cytometry assays, respectively. The expressions of miR-542-5p, miR-26b-5p, miR-572, miR-138-5p, miR-328-3p, miR-1254, Bcl-2, Bax, iNOS, COX-2, and MMP-13 were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR) or western blot. NO and PGE2 levels were detected by ELISA. All the cells extracted from the newborn rats were dyed blue, indicating that the cells were chondrocytes. IL-1ß could reduce the viability and promote apoptosis and inflammatory response of chondrocytes, while cedrol could reverse the effect of IL-1ß. In addition, cedrol could significantly increase the expression of miR-542-5p in IL-1ß-treated chondrocytes. Moreover, miR-542-5p inhibitor could partly reverse the effect of cedrol in the apoptosis and inflammation response of chondrocytes. Cedrol alleviated IL-1ß-induced apoptosis and inflammatory response of chondrocytes by promoting miR-542-5p expression.

Lentiviral-mediated shRNA against RelB induces the generation of tolerogenic dendritic cells.

OBJECTIVE: Lentiviral-mediated shRNA against RelB was used to produce tolerogenic dendritic cells from murine bone marrow derived dendritic cells (BMDCs). METHOD: RelB expression in the BMDCs was silenced by lentivirus carrying RelB shRNA. The apoptosis rate and surface markers of DCs were assessed by flow cytometry. IL-12,IL-10,TGF-ß1 secreted by DCs and DNA binding capacity of NF-κB subunits in the nucleus were measured by ELISA, independently. MLR was used to analyze the capacity of DCs to inhibit immune response. RESULTS: RelB expression was significantly inhibited in DCs following lentiviral mediated delivery of RelB specific shRNA. The RelB shRNA-DC produced lower IL-12 and higher IL-10 than mature dendritic cells (mDCs) and silencing control DCs. There was no difference in the apoptosis rate between shRNA RelB-DCs and mDCs. The expression levels of co-stimulatory molecules (CD80, CD86 and CD83) and MHC-II class molecule were lower in the RelB shRNA-DCs than in the mDCs and silencing control DCs. In addition, RelB shRNA also inhibited the RelB DNA binding capacity but had no effect on other NF-κB subunits. The shRNA RelB-DCs can significantly inhibit mixed lymphocyte reaction (MLR) and down-regulate Th1 cytokines and prompt the production of Th2 cytokines. CONCLUSION: Our results indicate RelB shRNA transfection of DCs can induce the immature status, and produce tolerogenic DCs.