外周血自然杀伤T细胞数目减少、抑制性受体上调和功能障碍可能参与手足口病重症化

目的探讨手足口病(hand foot and mouth disease,HFMD)患儿外周血自然杀伤T细胞(natural killer T cells,NKT)数目、表型及功能活性在不同病情、EV71感染中的变化及意义。方法应用流式细胞术检测39例健康儿童和55例HFMD患儿的外周NKT细胞数量、表型(NKD2A、CD94和NKG2D)及杀伤颗粒或细胞因子分泌功能(CD107a、GB或IFN-γ、IL-10)。酶联免疫吸附法检测血浆细胞因子和趋化因子(IL-2、IL-6、IL-10、TNF-α、IFN-γ和MCP-1)的水平。结果与健康儿童相比,重症(EV71~+/EV71~-)患儿NKT细胞数量及百分比均显著降低(P0.05);重症(尤其EV71~-重症)患儿NKT细胞表达抑制性NKG2A/CD94受体显著升高(P0.05);轻症患儿的NKT细胞分泌IL-10显著增多(P0.05);重症HFMD患儿血浆IL-6、TNF-α、IFN-γ和MCP-1的水平显著增高(P0.05);EV71-重症患儿IL-10水平明显增高(P0.05)。NKT细胞数目与CD107a~+NKT或GB~+NKT%呈正相关(P0.05);IL-10~+NKT%与NKG2D~+NKT%或IFN-γ~+NKT%呈正相关(P0.05)。结论随着HFMD病情进展,外周血NKT细胞数目减少,抑制性受体(NKG2A/CD94)表达上调,细胞因子分泌和细胞毒性功能障碍等,可能促进HFMD患儿免疫功能紊乱并参与HFMD重症化。     

白细胞介素-7在肠道病毒71感染所致的手足口病合并中枢神经系统损害患儿中的表达及对CD8~+T细胞功能的影响

目的观察白细胞介素-7(IL-7)在肠道病毒71感染(EV71)所致的手足口病(HFMD)合并中枢神经系统损害患儿中的表达,研究IL-7对CD8~+T细胞的调控作用。方法入组EV71感染所致的HFMD患儿48例(轻症HFMD 27例、伴有中枢神经系统损害的重症HFMD 21例),同时入组9例年龄、性别相匹配的健康对照者(HC)。分离血浆,纯化CD8~+T细胞,对重症HFMD患儿行腰椎穿刺术取脑脊液。酶联免疫吸附试验检测血浆和脑脊液中IL-7水平,实时定量PCR法检测CD127 mRNA相对表达量。使用重组人IL-7刺激纯化的CD8~+T细胞,观察分泌细胞增殖、分泌细胞因子和IL-7下游信号分子的表达变化。建立CD8~+T细胞和EV71感染的U-87MG细胞的直接接触和间接接触共培养系统,观察重组人IL-7对CD8~+T细胞功能的影响。结果伴有中枢神经系统损伤的重症HFMD患儿血浆中IL-7的表达水平较轻症HFMD和HC显著下降(P0.000 1)。脑脊液IL-7水平在影像学正常和异常的重症HFMD之间的差异无统计学意义(P=0.218)。CD8~+T细胞绝对计数及CD127 mRNA在CD8~+T细胞中的相对表达量在HC、轻症HFMD和重症HFMD之间的差异无统计学意义(P0.05)。重组人IL-7刺激不影响重症HFMD患儿外周血纯化的CD8~+T细胞的增殖,但可显著增加CD8~+T细胞分泌干扰素-γ(IFN-γ)和肿瘤坏死因子(TNF-α)的水平,同时CD8~+T细胞中信号传导及转录激活因子5的磷酸化及细胞因子信号抑制物3的表达均显著升高。重组人IL-7刺激可增强重症HFMD患儿CD8~+T细胞的细胞杀伤功能,主要表现为IL-7刺激后直接接触培养系统中靶细胞的死亡比例以及分泌IFN-γ和TNF-α的水平增加,而间接接触培养细胞中靶细胞死亡比例未见显著变化。结论 IL-7在伴有中枢神经系统损伤的重症HFMD患儿中的表达降低可能影响CD8~+T细胞的杀伤功能。     

模式识别受体TLR3、RIG-I和MDA5在慢性乙肝患者外周血的表达水平

目的:观察慢性乙型肝炎(CHB)患者外周血中单个核细胞胞膜和胞质模式识别受体mRNA的表达表达水平。方法:54例慢性乙型肝炎患者为实验组,40例健康体检者为对照组。采集实验组和对照组的新鲜空腹抗凝血,分离单个核细胞,提取单个核细胞中RNA,并反转录为c DNA,应用实时定量PCR技术检测Toll样受体3(TLR3)、维甲酸诱导基因-I(RIG-I)、黑色素瘤分化相关分子5(MDA5)、I型干扰素(IFN-α、IFN-β)、转录因子3(IRF-3)mRNA表达水平。结果:与正常对照组比较,实验组的TLR3、RIG-I、MDA5、IFN-α、IFN-β、IRF-3 mRNA表达水平均明显降低,具有显著性差异(P0.05)。高病毒载量组中的各分子表达水平与低病毒载量组和健康对照组比较降低更明显,且TLR3、RIG-I、MDA5、IFN-α、IFN-β、IRF-3mRNA水平分别与HBV-DNA的含量呈负相关(r=-0.697、-0.738、-0.867、-0.618、-0.415、-0.573)。结论:细胞胞膜(TLR3)和胞质(RIG-1、MDA5)模式识别受体、IFN-α、IFN-β、IRF-3 mRNA水平在慢性乙型肝炎患者的外周血单个核细胞中的表达降低,可能与HBV感染的慢性化状态有关。     

瑞香素对人PBMC的细胞因子和TLRs mRNA表达的影响

目的观察瑞香素对人外周血单个核细胞的细胞因子和Toll样受体表达的影响,研究瑞香素增强淋巴细胞功能的作用机制。方法分离人外周血T、B细胞和单核细胞,分别加入瑞香素,37℃,5%CO2培养48 h后,采用实时荧光定量PCR检测瑞香素对T细胞IL-2、IFN-γ,B细胞IL-12,单核细胞IL-1 mRNA及T、B细胞TLR1～10的mRNA表达的影响;同时检测先用抗TLR4单抗封闭,再用瑞香素处理细胞后上述细胞因子和TLRs的mRNA表达变化。结果瑞香素能明显上调T细胞IL-2及IFN-γ、B细胞IL-12、单核细胞IL-1 mRNA和T细胞TLR1、TLR4,B细胞TLR4、TLR9 mRNA的表达(P﹤0.05),其中T细胞IL-2、B细胞IL-12、单核细胞IL-1 mRNA的表达和T细胞TLR4,B细胞TLR4、TLR9 mRNA表达可被抗TLR4单抗部分阻断。结论瑞香素增强淋巴细胞的免疫功能的可能机制是通过上调T细胞TLR1、TLR4,B细胞TLR4、TLR9的表达,分别参与其细胞内信号转导,从基因转录水平促进T、B细胞分泌细胞因子。     

急性期过敏性紫癜患儿血清细胞因子及单核细胞Fcγ受体表达变化初探

目的 观察急性期过敏性紫癜(HSP)患儿单核细胞(MC) Fcγ受体(FcγR)表达变化,进一步探讨HSP免疫发病机制.方法 急性期HSP患儿30例,同年龄健康对照儿童15例.流式细胞术检测MC表面活化型受体FcγR Ⅰ和Fc-γRⅢ表达水平;实时荧光定量PCR(real-time PCR)检测活化型FcγRⅡa、抑制型FcγRⅡb、细胞因子(IL-1β、IL-6、TNF-α、IFN-α)、趋化因子(IP-10、RANTES、iNOS)和BLyS/April mRNA表达;试验酶联免疫吸附(ELISA)检测血浆IL-4、IL-10和TNF-α蛋白浓度.结果 (1)急性期HSP患儿MC FcγR Ⅰ和FcγRⅢ表达明显高于对照组(P＜0.05);FcγRⅡamRNA表达较对照组明显增高(P＜0.05),而FcγR Ⅱb mRNA表达较对照组显著降低(P＜0.05);(2)急性期HSP患儿MC细胞因子(IL-1β、IL-6、TNF-α、IFN-α)、趋化因子(IP-10、RANTES、iNOS)及BLyS/April表达均明显高于正常对照组(P＜0.05),相关性分析发现细胞因子和趋化因子与FcγRⅡa/FcγRⅡb均呈正相关;(3)急性期HSP患儿血浆炎症细胞因子IL-4、IL-10和TNF-α浓度显著增高(P＜0.05),其中TNF-α浓度与MC FcγRⅡb mRNA表达呈负相关(r=-0.73,P＜0.05).结论 急性期HSP出现细胞因子表达异常和单核细胞活化型/抑制型Fcγ表达失衡.     

甲型流感病毒天然免疫机制研究进展CSCD

流行性感冒病毒,简称流感病毒,属于正粘病毒科.流感病毒感染宿主后,急性高热、全身疼痛、显著乏力和呼吸道症状是其典型的临床症状.感染宿主后,可引起Toll样受体、RIG-Ⅰ样受体和NOD样受体等宿主模式识别受体介导的抗病毒信号通路的激活,诱导干扰素和IL-1,IL-18等细胞因子表达,起到抗病毒的作用.本文对这三类PRRs的作用机制进行阐述.     

传染性单核细胞增多症患儿NKG2D表达变化初探

目的 观察传染性单核细胞增多症(infectious mononucleosis,IM)患儿自然杀伤(NK)细胞和CD8+T细胞NKG2D表达,探讨导致Epstein-Barr病毒(EBV)感染免疫功能紊乱的可能机制.方法 传染性单核细胞增多症患儿29例,同龄健康对照组25例.流式细胞术检测外周血NK细胞、CD8+T细胞表面激活性受体NKG2D及抑制性受体NKG2A表达,CD14+单核细胞(MC)表面NKG2D配体MHC Ⅰ相关分子A(MICA)与人巨细胞病毒蛋白UL16的结合蛋白1(ULBP-1)表达;酶联免疫吸附试验(EHSA)检测血浆游离MICA (sMICA)、IL-7、IL-12、IL-15、IFN-γ及TGF-β等细胞因子浓度.结果 (1)IM组患儿NK细胞及CD8+T细胞表面NKG2D表达明显低于对照组(P＜0.05),其中3例拟诊EBV-相关噬血细胞综合征(EBV-HLH)患儿表达下调最为显著;(2)IM组患儿CD14+ MC MICA与ULBP-1表达与对照组相比差异无统计学意义(P＞0.05);(3)IM患儿细胞因子IL-15与TGF-β较对照组降低,IL-7、IL-12、IFN-γ及sMICA较对照组升高;(4)IM患儿NK细胞NKG2A表达明显高于对照组(P＜0.05),CD8+T细胞NKG2A表达与对照组相比无明显差异(P＞0.05).结论 EBV感染患儿NK细胞、CD8+T细胞NKG2D表达过度下调可能是导致免疫功能紊乱的原因之一,IL-15及IL-12等细胞因子调控失衡,sMICA血浓度增高等多种因素可能与其NKG2D表达下调有关.     

静脉注射丙种球蛋白治疗对急性期川崎病IgGFc受体和TLR4表达的影响

目的 探讨静脉注射丙种球蛋白(intravenous immunoglobulin,IVIG)治疗对川崎病(Kawasaki disease,KD) Toll样受体4(Toll-like receptor4,TLR4)表达的影响.方法 急性KD患儿25例,正常同龄对照儿童15例.流式细胞术检测单核细胞(monocyte cells,MC) TLR4表达水平;双抗体夹心酶联免疫吸附试验(ELISA)检测血浆TNF-α浓度;反转录-聚合酶链反应(RT-PCR)及荧光定量PCR检测MC FcγRⅡb、TLR4信号转导途径分子(MyD88、TRAF-6、TAKl)和细胞因子(IL-1β、IL-6、TNF-α)mRNA表达.结果 急性期KD患儿MC TLR4及其转导分子表达明显高于同龄对照组(P＜0.05),IVIG治疗后较治疗前明显降低(P＜0.05);急性期KD患儿MC FcγRⅡb明显低于同龄对照组(P＜0.05),IVIG治疗后明显升高(P＜0.05);急性期KD患儿IL-1β、IL-6、TNF-α表达及血浆TNF-α浓度显著增高(P＜0.05),IVIG治疗后下降(P＜0.05);急性期KD患儿MC FcγRⅡb表达与TLR4表达及炎症细胞因子呈相关性(P＜0.05).结论 IVIG可能上调FcγRⅡb表达,下调TLR4表达,从而抑制炎症反应.     

蝙蝠蛾被毛孢菌丝体通过激活TLR2、TLR4和Dectin-1诱导Th1型免疫反应

目的:研究蝙蝠蛾被毛孢菌丝体(MHCS)对抗原呈递细胞树突状细胞(Dendritic cells,DCs)成熟和功能的调节作用.方法:利用流式细胞术、实时荧光定量PCR、Western blot和混合淋巴细胞培养等实验方法,检测了MHCS对DCs成熟和功能相关表面分子、细胞因子表达以及Toll样受体(TLR)2、TLR4和Dectin-1相关信号转导通路蛋白活性的调节作用.结果:MHCS显著上调DCs表面分子CD11c、MHCⅠ和MHC Ⅱ、辅助刺激分子CD40、CD80和CD86以及模式识别受体TLR2、TLR4和Dectin-1的表达;促进Th1型细胞因子IL-12产生,抑制Th2型细胞因子IL-10、IL-13和TGF-β1产生;诱导TAK1和IRF3磷酸化活性增加.MHCS也显著刺激幼稚型Th1细胞增殖,诱导幼稚型Th细胞向Th1方向分化.利用中和性抗体,分别阻断DCs细胞TLR2、TLR4或Dectin-1活性,可部分抑制MHCS诱导的DCs成熟.结论:MHCS能促进DO成熟,诱导Th1型免疫反应.MHCS的这些作用与其激活模式识别受体TLR2、TLR4或Dectin-1有关.     

TLR4介导的BV-2细胞抗HCV固有免疫应答机制初步研究

目的:观察BV-2细胞感染HCV后IFN-β、IL-6分泌和TLR4表达相关性,初步探讨TLR4是否介导参与中枢神经系统抗HCV固有免疫应答及其可能机制。方法:将BV-2细胞接种于24孔培养板,贴壁后换用含20%HCV阳性血清的培养液感染细胞,为HCV实验组,同时设正常血清组和空白对照组。应用流式细胞术检测各组BV-2细胞TLR4蛋白水平的表达;用RT-PCR观察阻断TLR4后各组BV-2细胞TLR4mRNA表达变化;用ELISA检测阻断TLR4后各组BV-2细胞IFN-β、IL-6分泌变化。结果:HCV实验组TLR4表达和IFN-β、IL-6分泌均高于正常血清组及空白对照组(P<0.01);阻断TLR4的HCV实验组TLR4mRNA表达及IFN-β、IL-6分泌明显低于非阻断组(P<0.01)。结论:HCV感染中枢神经系统后,TLR4可通过启动下游细胞因子IL-6、IFN-β等的转录和翻译,介导参与宿主抗HCV固有免疫应答过程。     

A whole blood assay to assess peripheral blood dendritic cell function in response to Toll-like receptor stimulation

We report a practical technique to assess peripheral blood dendritic cell (DC) maturation and function in whole blood (WB), which requires minimal blood volumes and minimizes ex vivo manipulations of clinical specimens. We determined optimal conditions for flow cytometric analysis of markers of DC maturation, including CCR7, CD25, CD80 and CD83, and of the intracellular cytokines, tumor necrosis factor- (TNF-) and interferon- (IFN-), in both myeloid (mDC) and plasmacytoid (pDC) lineages. We demonstrate concentration-dependent production of these cytokines by DC following short-term stimulation with ligands to Toll-like receptors (TLRs) 2/1, 3, 4, 7, 8 and 9. Kinetic studies revealed maximal TNF- and IFN- protein expression at 2 to 3 h after stimulation with certain TLR ligands. Finally, utilizing cells from a cohort of eight healthy donors, we compared DC responses to TLR activation in WB, freshly isolated peripheral blood mononuclear cells (PBMC) and cryopreserved PBMC. We found that TNF- responses were essentially preserved, but IFN- responses were profoundly diminished or entirely abrogated following cryopreservation. In conclusion, we propose that WB analysis of peripheral DC function is a rapid, reliable and simple method to evaluate TLR function in clinical specimens, which obviates artifact-prone cell purification. The major impact of cryopreservation on some DC responses further strengthens the case for a rapid method that uses fresh blood.     

Functional characterization of ex vivo blood myeloid and plasmacytoid dendritic cells after infection with dengue virus

Myeloid and plasmacytoid dendritic cells (mDC and pDC) are naturally distinctive subsets. We exposed both subsets to dengue virus (DV) in vitro and investigated their functional characteristics. High levels of DV replication in mDC were found to correlate with DC-SIGN expression. Production of inflammatory cytokines by mDC increased gradually after DV-infection, which was dependent on DV replication. Co-stimulatory markers were upregulated on mDC upon DV-infection. On the contrary, lower levels of DV-replication were observed in pDC, but the cytokine production in pDC was quicker and stronger. This cytokine response was not dependent on viral replication, but dependent on cell endosomal activity and TLR7, and could be also induced by purified DV genome RNA. These results clearly suggested functional differences between mDC and pDC in response to DV infection. Additionally, the TLR7-mediated recognition of DV RNA may be involved in pDC functional activation.     

Fusion protein of TLR5-ligand and allergen potentiates activation and IL-10 secretion in murine myeloid DC

Toll-like receptor ligands are immune-modulatory components linking innate and adaptive immune responses and are considered to be promising vaccine components. Objective of this study was to investigate the adjuvant activity of Listeria monocytogenesis-derived TLR5-ligand flagellin A (flaA) genetically fused to ovalbumin (Ova, major chicken white egg allergen) in a murine in vitro system. Recombinant flaA, rOva, and a fusion protein of rflaA and rOva (rflaA:Ova) were over-expressed in Escherchia coli and purified by FPLC. LPS depletion was confirmed by LAL test. TLR5-binding was evaluated by human and murine TLR5-transgenic HEK 293 cells. The immune-modulatory effect of rflaA:Ova and rflaA:Ova modified by reduction and alkylation on purified BALB/c bone marrow-derived myeloid (mDC) and plasmacytoid dendritic cells (pDC) was investigated by flow cytometry and intracellular cytokine staining (ICS). Dose-dependent IL-8 secretion from transgenic HEK 293 cells confirmed binding of rflaA and rflaA:Ova molecules to human and murine TLR5. Recombinant flaA showed similar biological reactivity to TLR5-ligand fliC derived from Salmonella typhimurium applied as positive control. Compared to rflaA, both rflaA:Ova preparations induced higher expression of maturation markers (CD40, CD69, CD80, and CD86) on mDC, whereas only CD69 and CD40 were upregulated on pDC. Moreover, IL-6 and IL-10 production by mDC was enhanced upon stimulation with rflaA:Ova constructs in comparison to an equimolar mixture of both proteins whereas pDC did not show secretion of the investigated cytokines. Any immunological effects of LPS can be excluded by depletion of endotoxins and the lack of IL-10 production upon proteinase K digestion of rflaA:Ova. In summary, the rflaA:Ova fusion proteins showed an enhanced immune modulating capacity in comparison to rflaA or the mixture of rflaA and antigen. Since the rflaA:Ova fusion proteins induce strong IL-10 induction they are considered as potential vaccine candidates to improve allergen-specific immunotherapy.     

Co-stimulation with TLR3 and TLR21 ligands synergistically up-regulates Th1-cytokine IFN-γ and regulatory cytokine IL-10 expression in chicken monocytes

Toll-like receptors (TLRs) are pattern recognition receptors of the innate immune system for various conserved pathogen-associated molecular motifs. Chicken TLR3 and TLR21 (avian equivalent to mammalian TLR9) recognize poly I:C (double-stranded RNA) and CpG-ODN (a CpG-motif containing oligodeoxydinucleotide), respectively. Interaction between TLR3 and TLR21 agonists poly I:C and CpG-ODN has been reported to synergize in expression of proinflammatory cytokines and chemokines and the production of nitric oxide in chicken monocytes. However, the interaction between poly I:C and CpG-ODN on the expression of interferons (IFNs) and Th1/Th2 cytokines remains unknown. The objective of the present study was to investigate the effect of the interaction between poly I:C and CpG-ODN on the mRNA expression levels of IFN-α and IFN-β, Th1 cytokines IFN-γ and IL-12, Th2 cytokine IL-4, and regulatory IL-10 in chicken monocytes. When stimulated with either agonist alone, CpG-ODN significantly up-regulated the expression of INF-γ, IL-10, and IL-12p40, but not IFN-α and IFN-β; whereas poly I:C induced the expression of INF-γ, IFN-α, IFN-β, and IL-10; but not IL-12p40. However, stimulation with a combinatory CpG-ODN and poly I:C further synergistically increased the expression of IFN-γ and IL-10 mRNA. Our results provide strong evidence supporting the critical role of TLR3 and TLR21 in avian innate immunity against both viral and bacterial infections; and the synergistic interaction between the TLR3 and TLR21 pathways produces a stronger Th1-biased immune response in chicken monocytes. Our result also suggest a potential use of poly I:C and CpG-ODN together as a more efficient adjuvant for poultry vaccine development.     

慢性HCV感染者外周血中髓样和浆样树突状细胞频数和表型研究

目的 探讨慢性HCV感染者外周血中髓样树突状细胞(mDC)和浆样树突状细胞(pDC)频数和表型的变化,并分析其与丙型肝炎临床指标间的相关性.方法 采用流式细胞术检测HCV感染者及健康对照外周血中mDC和pDC的频数及细胞表面共刺激分子HLA-DR、CD83、CD86、CD40和共抑制分子PD-L1的表达水平,并分析DC频数与HCV感染者血浆病毒载量、谷丙转氨酶(ALT)的相关性.结果 与健康对照组相比,HCV感染者外周血中mDC和pDC的频数明显降低(患者组分别为0.37±0.19和0.19±0.12,对照组为0.51±0.18和0.29±0.13,P＜0.05),且mDC频数与血浆HCV载量和血清ALT水平呈负相关(r=-0.5878,P＜0.0001;r=-0.4628,P=0.003).患者mDC和pDC表面共刺激分子HLA-DR、CD83、CD86、CD40以及共抑制分子PD-L1的表达均有不同程度升高,差别有统计学意义(共刺激分子P＜0.01,共抑制分子P＜0.05或0.01).结论 慢性HCV感染者外周血mDC和pDC频数下降,但DC表面共刺激分子和共抑制分子的表达均明显升高.该结果提示mDC数量的减少可能与HCV的慢性持续性感染有关.

Abstract：

Objective To explore the frequencies and phenotype of myeloid and plasmacytoid dendritic cells (mDC and pDC) in chronic HCV infection and to investigate the relationships between DC frequencies and HCV viral load and serum ALT level. Methods PBMC were isolated from chronic HCV infected patients and healthy control. Multi-color flow cytometry was used to analyze the frequencies and surface marker expression on mDC and pDC. The relationship between DC frequencies and viral load and ALT level was also calculated. Results In comparison with healthy control, frequencies of mDC and pDC in chronic HCV infection were significantly decreased (0. 37 ± 0. 19 and 0. 19 ± 0. 12 vs 0. 51 ± 0. 18 and 0. 29 ± 0.13, P＜0.05). The frequency of mDC was negatively correlated with HCV viral load (r= -0.5878, P ＜ 0. 0001 ) and serum ALT level ( r = - 0. 4628 , P = 0. 003 ). Both costimulatory markers ( HLA-DR, CD83, CD86, and CD40) and coinhibitory marker (PD-L1) expression on mDC and pDC in HCV infection were increased (P＜0.01 for costimulatory marker, P＜0.05 or F＜0.01 for coinhibitory marker). Conclusion The frequencies of mDC and pDC in chronic HCV infection were decreased, while the expression of costimulatory markers and coinhibitory marker were increased or not decreased in HCV infection. The decreased frequency of mDC was probably related to persistance of HCV infection.     

Maturation and cytokine production potential of dendritic cells isolated from rheumatoid arthritis patients peripheral blood and induced in vitro

BackgroundSince dendritic cells (DC) are involved in the development of autoimmune inflammation, researchers consider DC both as target cells for specific therapy of rheumatoid arthritis (RA) and as candidate cells for the development of cell-based methods to treat autoimmune diseases. The development of treatment strategies requires comprehensive research into the quantitative and qualitative characteristics of DC subtypes both ex vivo from RA patients and in vitro, to determine the possibility of inducing functionally mature DC in RA.ObjectiveTo study the phenotypic and functional properties of myeloid (mDC) and plasmacytoid (pDC) DC isolated from the peripheral blood of patients with RA and induced in vitro.Materials and methodsBlood samples were obtained from RA patients and healthy donors. Immature DC in the whole blood and in vitro induced DC were characterized by the positive expression of CD80, CD83, CCR7, IL-10, IL-4, IL-12 and IFN-α. R848 and lipopolysaccharide were used to determine DC maturation ability. From PBMCs of RA patients and health donors DCs with myeloid (imDC) and plasmacytoid (ipDC) phenotype were induced.ResultsThe relative count of mDC in the peripheral blood between studied groups did not differ. pDC count was significantly lower for RA patients. DC from RA patients were characterized by low expression levels of CD80 and CD83 on both populations cells and high expression of CCR7 only on pDC. An increase in pDC producing IL-12 and IFN-α and a decrease in mDC and pDC producing IL-4 and IL-10 were shown in RA. imDC and ipDC obtained from RA patients according to their phenotype and cytokine profile did not differ from those obtained from healthy donors.ConclusionsThere is an imbalance between subpopulations of DC in the peripheral blood of RA patients. DC of RA patients are less mature. The data suggest the involvement of DC in RA pathogenesis and confirm DC participation in balance shift towards Th1-type immune responses. At the same time, in vitro induced RA DC are phenotypically and functionally competent.     

Blueprints of Signaling Interactions between Pattern Recognition Receptors: Implications for the Design of Vaccine Adjuvants

Innate immunity activation largely depends on recognition of microorganism structures by Pattern Recognition Receptors (PRRs). PRR downstream signaling results in production of pro- and anti-inflammatory cytokines and other mediators. Moreover, PRR engagement in antigen-presenting cells initiates the activation of adaptive immunity. Recent reports suggest that for the activation of innate immune responses and initiation of adaptive immunity, synergistic effects between two or more PRRs are necessary. No systematic analysis of the interaction between the major PRR pathways were performed to date. In this study, a systematical analysis of the interactions between PRR signaling pathways was performed. PBMCs derived from 10 healthy volunteers were stimulated with either a single PRR ligand or a combination of two PRR ligands. Known ligands for the major PRR families were used: Toll-like receptors (TLRs), C-type lectin receptors (CLRs), NOD-like receptors (NLRs), and RigI-helicases. After 24 h of incubation, production of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), IL-6, and IL-10 was measured in supernatants by enzyme-linked immunosorbent assay (ELISA). The consistency of the PRR interactions (both inhibitory and synergistic) between the various individuals was assessed. A number of PRR-dependent signaling interactions were found to be consistent, both between individuals and with regard to multiple cytokines. The combinations of TLR2 and NOD2, TLR5 and NOD2, TLR5 and TLR3, and TLR5 and TLR9 acted as synergistic combinations. Surprisingly, inhibitory interactions between TLR4 and TLR2, TLR4 and Dectin-1, and TLR2 and TLR9 as well as TLR3 and TLR2 were observed. These consistent signaling interactions between PRR combinations may represent promising targets for immunomodulation and vaccine adjuvant development.