Plasmodium yoelii 17XL infection modified maturation and function of dendritic cells by skewing Tregs and amplificating Th17
BMC INFECTIOUS DISEASES
Authors: Chen, Guang; Du, Ji-wei; Nie, Qing; Du, Yun-ting; Liu, Shuang-chun; Liu, De-hui; Zhang, Hui-ming; Wang, Fang-fang
Abstract
Background Emerging data has suggested that Tregs, Th17, Th1 and Th2 are correlated with early immune mechanisms by controlling Plasmodium infection. Plasmodium infection appeared to impair the antigen presentation and maturation of DCs, leading to attenuation of specific cellular immune response ultimately. Hence, in this study, we aim to evaluate the relevance between DCs and Tregs/Th17 populations in the process and outcomes of infection with Plasmodium yoelii 17XL (P.y17XL). Methods DCs detection/analysis dynamically was performed by Tregs depletion or Th17 neutralization in P.y17XL infected BALB/c mice via flow cytometry. Then the levels of cytokines production were detected using enzyme-linked mmunosorbent assay (ELISA). Results Our results indicated that Tregs depletion or Th17 neutralization in BALB/c mice infected with P.y17XL significantly up-regulated the percentages of mDC and pDC, increased the expressions of major histocompatibility complex (MHC) class II, CD80, CD86 on DCs and the levels of IL-10/IL-12 secreted by DCs, indicating that abnormal amplification of Tregs or Th17 may damage the maturation and function of DCs during the early stage of malaria infection. Interestingly, we also found that the abnormal amplification of Th17, as well as Tregs, could inhibit the maturation of DCs. Conclusions Tregs skewing or Th17 amplification during the early stage of malaria infection may inhibit the maturation and function of DCs by modifying the subsets of DCs, expressions of surface molecules on DCs and secretion mode of cytokines.
Bone marrow dendritic cells deficient for CD40 and IL-23p19 are tolerogenic in vitro
IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES
Authors: Kalantari, Tahereh; Ciric, Bogoljub; Kamali-Sarvestani, Eskandar; Rostami, Abdolmohamad
Abstract
Objective(s): In addition to pro-inflammatory role, dendritic cells (DCs) can also be anti-inflammatory when they acquire tolerogenic phenotype. In this study we tested the role of CD40 and IL-23p19 in antigen presenting function of bone marrow-derived DCs (BMDCs) by comparing BMDCs derived from CD40 knockout (CD40KO-DCs) and IL-23p19 (IL-23p19KO-DCs) knockout mice with those from C57BL/6 mice (Cont-DCs). We have focused on CD40 and IL-23, as these molecules have well established pro-inflammatory roles in a number of autoimmune and inflammatory diseases. Materials and Methods: The expression of maturation markers MHC II and co-stimulatory molecules CD40, CD80, and CD86 was analyzed by flow cytometry, while the expression of CD40 and IL-23p19 was measured by RT-PCR. The capacity of BMDCs to activate CD4+ T cells was evaluated by 3H-thymidine incorporation, and the capacity of BMDCs to uptake antigen was evaluated using fluorescent OVA and flow cytometry. Results: The lack of CD40 or IL-23p19 had no effect on uptake of FITC-OVA by the DCs, confirming their immature phenotype. Moreover, CD40KO-DCs had significantly reduced capacity to stimulate proliferation of CD4+ T cells. CD4+ T cells activated by CD40KO-DCs and IL-23p19KO-DCs produced significantly less IFN-gamma (P-value <= 0.05), while CD4+ T cells stimulated by IL-23p19KO-DCs produced less GM-CSF and more IL-10 than Cont-DCs. Conclusion: This study shows that CD40KO-DCs and IL-23p19KO-DCs have a marked tolerogenic potency in vitro. Future in vivo studies should determine if and to what extent DCs lacking CD40 or IL-23 have a potential to be useful in therapy of autoimmune inflammation.