慢性乙型肝炎患者在HBV不同抗原负载下树突状细胞功能的变化

目的观察在不同HBV抗原负载下树突状细胞(DC)功能的变化及在核苷(酸)类药物抗病毒治疗后DC的功能变化。方法分离17例慢性乙型肝炎患者外周血单个核细胞(PBMC),并在不同抗原负载下(HBsAg、HBcAg、HBsAg联合HBcAg)诱导DC分化成熟,用流式细胞技术测定DC表面共刺激分子CD80、CD83、CD1a及HLA-Ⅱ类分子HLA-DR表达水平,同时用淋巴细胞增殖试验评估DC功能。结果与负载HBsAg诱导相比,HBcAg、HBsAg联合HBcAg诱导下DC共刺激分子表达明显增强(HLA-DR:85.12±1.55比98.37±1.27比99.21±1.33;CD1a:15.69±2.46比16.25±2.33比42.20±1.10;CD80:71.88±6.38比80.74±3.23比94.70±2.77;CD83:32.64±2.77比42.55±2.88比44.16±1.89)。淋巴细胞增殖试验提示DC功能改善更显著,尤其HBsAg联合HBcAg诱导DC功能改善更加明显(HBV DNA阳性:7.29±0.17比7.99±0.43比8.56±0.31;HBV DNA阴性:7.48±0.30比8.22±0.41比8.78±0.31)。将17例慢性乙型肝炎患者在核苷(酸)类药物抗病毒治疗前后DC功能进行比较,经抗病毒治疗在充分抑制HBV DNA复制的情况下,DC功能的恢复更趋于完善(HLA-DR:99.21±1.33比99.82±2.67;CD1a:42.20±1.10比71.33±5.89;CD80:94.70±2.77比96.42±3.56;CD83:44.16±1.89比68.34±2.11)。结论 HBsAg联合HBcAg诱导DC细胞功能明显得到恢复和增强,HBV DNA阴性时诱导自体DC功能恢复更趋完善。     

乙型肝炎相关肝癌外周血树突状细胞负载肿瘤抗原前后免疫功能的变化

目的探讨肝癌患者外周血单个核细胞(PBMC)来源树突状细胞(DC)表面分子表达及负载肿瘤抗原前后免疫功能变化与免疫逃逸的关系。方法分离18例乙型肝炎相关原发性肝癌、11例乙型肝炎肝硬化患者和10名健康献血者PBMC,体外培养,并加入重组人粒细胞巨噬细胞集落刺激因子(GM-CSF)和白细胞介素-4(IL-4)诱导DC。以共聚焦显微镜和扫描电镜观察形态,以流式细胞仪检测DC表面人类白细胞抗原(HLA)-DR、CD1a、CD80、CD83、CD86等分子表达水平。以HCCLM6肝癌细胞株制备肿瘤抗原,分别负载3种DC,最后以混合淋巴细胞反应(MLR)测定DC负载前后刺激同种异型T淋巴细胞增殖能力,并测定MLR上清液中IL-12的含量。结果肝硬化和肝癌组PBMC、DC得率低于正常组(P<0.05);HLA- DR、CD1a、CD80和CD86等分子表达水平也低于正常组(P<0.05);负载肿瘤抗原前肝硬化和肝癌组刺激同种异型T淋巴细胞增殖能力和MLR上清液中IL-12含量明显低于正常组,负载肿瘤抗原后3组均提高, 并以肝硬化组提高最为明显,但IL-12含量仍低于正常组。结论DC表型和功能缺陷可能是乙型肝炎病毒产生免疫耐受和肝癌细胞免疫逃逸的重要机制。肝硬化患者DC仍有一定功能。     

含CpG基序寡核苷酸对慢性乙型肝炎患者外周血树突状细胞的免疫激活研究

目的 研究含非甲基化CpG基序的寡核苷酸（CpG-ODN）对慢性乙型肝炎患者（CHB）外周血树突状细胞（DC）表型和功能的影响。方法以CD14磁性分选微珠分离CHB患者外周血高纯度单核细胞；以重组人粒细胞巨噬细胞集落刺激因子（hGM—CSF）、重组人白细胞介素-4（hIL-4）诱导扩增DC；以CpG-ODN刺激DC成熟，并与肿瘤坏死因子（TNF）-n比较，评价其对DC表达表面分子人类白细胞组织相容性抗原（HLA）-DR、CD86、CD1a，分泌IL-12p70以及刺激同种T细胞增殖能力的影响。结果与non—ODN和磷酸盐缓冲液（PBS）组比较，CpG-ODN能明显提高CHB患者外周血DC表面分子HLA—DR、CD86的表达，使IL-12分泌增加，刺激同种异体T细胞增殖的能力亦显著增强（P=0．017和0．023），但不能明显提高CD1a的表达；CpG-ODN的上述刺激作用接近或略逊于hTNF-α，但差异无统计学意义（P〉0．05）。结论CpG-ODN与hTNF-α一样能够促进CHB患者外周血DC成熟进而增强其抗原提呈功能。     

HBsAg、HBcAg活化树突状细胞治疗慢性乙型肝炎的体外研究

目的 研究慢性乙型肝炎患者外周血树突状细胞(DC)经HBsAg、HBcAg活化后的免疫功能.方法 从慢性乙型肝炎患者外周血中培养扩增DC,在DC成熟前,加入纯的HBsAg、HBcAg刺激,用流式细胞仪检测DC表型,用液闪计数仪观察DC对T细胞的增殖作用,用ELISA法检测混合淋巴细胞反应(MLR)中细胞因子的分泌水平.结果 经HBcAg刺激DC的CD86表达率为(92.14±5.12)%,明显高于HBsAg刺激组和未加抗原组(P＜0.01);经HBcAg刺激组DC诱导同种异体静止T细胞增殖的能力每分钟液闪计数值(cpm)为34259±3127,明显高于HBsAg刺激组(20258±2917)和单个核细胞组(3469±417),P＜0.01;经HBcAg刺激组DC MLR中IL-12浓度为(342±42.3)ng/L,分别高于HBsAg刺激组和未加抗原组(P＜0.01).结论 体外经HBcAg刺激DC可有效提呈抗原病毒,并可进一步刺激T细胞产生.     

胞质转导肽-HBcAg18-27-Tapasin体外诱导HBV转基因小鼠髓源性树突状细胞成熟及在T淋巴细胞增殖中的作用

目的:观察融合蛋白胞质转导肽(cytoplasmic transduction peptide,CTP)-HBcAg18-27-Tapasin体外诱导HBV转基因小鼠髓源性树突状细胞(dendritic cell,DC)成熟和对T淋巴细胞增殖的作用.方法:体外分离、培养HBV转基因小鼠及近交系C57BL/6小鼠髓源性DC,加入重组粒细胞-巨噬细胞集落刺激因子和白介素(interleukin,IL)-4培养5d,再加入实验组10μg/mL CTP-HBcAg18-27-Tapasin、对照组10μg/mL CTP-HBcAg18-27、10μg/mL HBcAg18-27-Tapasin及空白组RPMI1640完全培养液.流式细胞术测定DC表面分子CD80、CD83、MHC-1的表达,ELISA法测定DC培养上清液中的IL-12p70的水平,细胞计数试剂盒(CCK-8)检测T淋巴细胞增殖反应,流式细胞仪检测增殖的T淋巴细胞内的细胞因子.结果:体外成功诱导小鼠髓源性DC;CTP-HBcAg18-27-Tapasin能明显上调DC表面分子CD80、CD83、MHC-1的表达;并且CTP-HBcAg18-27-Tapasin组诱导DC分泌的IL-12p70水平及诱导DC增殖T淋巴细胞增殖能力明显高于对照组及空白组[IL-12p70转基因小鼠(F=205.85,P=0.000);C57BL/6小鼠(F=406.20,P=0.000)];流式细胞仪检测实验组融合蛋白诱导的CTL水平也高于对照组[转基因小鼠(F=155.45,P=0.000);C57BL/6小鼠(F=392.90,P=0.000)],同时HBV转基因小鼠DC表面分子及在T淋巴细胞增殖中的作用要比C57BL/6小鼠低.结论:分子伴侣Tapasin修饰胞内化抗原肽能促进HBV转基因小鼠髓源性DC的分化、成熟,并能增强DC刺激T淋巴细胞增殖能力及诱导CTL的产生.     

PTD-HBcAg体外诱导小鼠髓源性树突状细胞成熟及在T淋巴细胞增殖中的作用

目的 观察融合蛋白PTD-HBcAg诱导体外培养的小鼠髓源性树突状细胞(DC)成熟及对T淋巴细胞增殖的作用.方法 体外分离培养近交系BALB/C小鼠髓源性DC加入重组粒细胞-巨噬细胞集落刺激因子(rgM-CSF)、重组IL-4培养5 d,再加人TNF-a、HBcAg和PTD-HBcAg诱导DC成熟.激光共聚焦显微镜观察免疫荧光在细胞中的分布及定位,流式细胞计数仪测定DC表面分子表达,ELISA法测定DC培养上清液中IL-12 p70的水平,CCK-8试剂盒检测T淋巴细胞增殖反应.组间数据比较采用t检验.结果 成功体外诱导培养小鼠髓源性DC,HBcAg主要定位于DC膜表面,而PTD-HBcAg能够穿透DC膜进入细胞质.PTD-HBcAg能明显上调DC表面分子CD80、CD86和主要组织相容性复合体(MHC)II类分子表达;50 mg/L和100 mg/L PTD-HBcAg诱导DC分泌IL-12 p70水半分别为(142.50±18.31)ng/L和(124.30±15.12)ng/L,明显高于HBcAg诱导组的(42.31±4.21)ng/L(t=9.234和9.045,均P＜0.05);PTD-HBcAg诱导DC刺激T淋巴细胞增殖能力明显高于HBcAg组及阳性对照TNF-a组.结论 PTD-HBcAg具有穿透DC膜能力,并能促进DC分化、成熟,明显上调表面共刺激分子表达,增强DC刺激T淋巴细胞增殖能力及分泌IL-12 p70的水平.     

CpG-ODN联合HBsAg对慢性乙型肝炎患者外周血树突状细胞表型和功能的影响

目的　研究含非甲基化CpG基序的免疫刺激寡核苷酸 (CpG- ODN)与重组HBsAg对慢性乙型肝炎患者 (CHB)外周血树突状细胞 (dendriticcell ,DC)表型和功能的影响。方法　以重组人GM CSF、IL 4自CHB患者和健康者外周血单个核细胞诱导扩增DC ;以CpG ODN和HBsAg单独或联合刺激DC ,并与TNF α比较 ,评价其对DC表达表面分子HLA DR、CD86、CD1a ,分泌IL 12p70以及刺激同种T细胞增殖能力的影响 ;同时检测血浆TGF- β、IFN- γ含量。 结果　与PBS组比 ,CpG- ODN单用或联合HBsAg均能明显提高CHB患者DC表面分子HLA DR的表达 ,使IL- 12分泌增加 ,刺激同种T细胞增殖的能力亦增强 ,CpG ODN联合HBsAg尚能明显提高CD1a的表达 ;CpG- ODN的上述刺激作用类似于TNF α ;CHB患者血浆TGF- β、IFN -γ含量明显高于正常对照。 结论　CpG -ODN与TNF α一样能够促进CHB患者外周血DC分化和成熟 ;CpG- ODN与HBsAg联合刺激能协同增强DC的特异性抗原递呈作用 ;CHB患者的细胞因子环境可能是DC功能沉默的重要原因。     

CpG-ODN对慢性乙型肝炎患者外周血树突状细胞表型和功能的影响

研究含非甲基化CpG基序的寡核苷酸(CpG-ODN)对慢性乙型肝炎患者(CHB)外周血树突状细胞(den- dritic cell,DC)表型和功能的影响。以CpG-ODN刺激CHB和健康者外周血单核细胞衍生的DC成熟,结果显示,与 non-ODN和PBS组比,CpG-ODN能明显提高CHB患者DC的HLA-DR、CD86表达,使其IL-12分泌增加,刺激T 细胞增殖的能力亦显著增强(P<0．05),但不能明显提高CD1a表达。因此,CpG-ODN与TNF-α一样能促进CHB 患者外周血DC成熟进瓶增强其抗原提呈功能;CHB患者的細胞因子环境可能是DC功能沉默的重要原因。     

CpG寡核苷酸联合HBsAg对慢性乙型肝炎患者树突细胞功能及核因子活性的影响

目的 研究含CpG寡核苷酸(CpG-ODN)联合重组HBsAg对慢性乙型肝炎(CHB)患者外周血树突状细胞(DC)表型和功能及其对核因子-κB和激活蛋白-1活性的影响.方法 以重组细胞因子联合诱导扩增CHB患者外周血单个核细胞得到DC;以CpG-ODN和HBsAg及肿瘤坏死因子α刺激DC,评价其表型、功能和胞核核因子-κB、激活蛋白-1活性.结果 CpG-ODN联合HBsAg明显提高CHB患者DC表面分子人类白细胞抗原-DR表达、白细胞介素-12分泌以及刺激同种T淋巴细胞增殖的能力,尤其能提高CD1a的表达.上述免疫佐剂能增强DC细胞核因子κB活性,同时抑制激活蛋白-1活性.结论 CpG-ODN与hTNF α一样能够促进CHB患者外周血DC成熟;其作用机制可能是选择性激活或抑制DC胞内不同核因子活性.     

负载肿瘤抗原的DC体外诱导抗肿瘤免疫反应的实验研究

目的 研究自体及同种异体树突状细胞(DC)体外负载肿瘤抗原后刺激T淋巴细胞增殖及诱导抗肿瘤免疫反应的能力.方法 利用细胞因子诱导人骨髓单个核细胞生成DC,尼龙毛柱法分离T淋巴细胞,3H-TdR掺入法检测负载肺癌细胞凋亡小体的自体及同种异体DC体外刺激T细胞增殖反应,乳酸脱氢酶(LDH)释放法检测负载肺癌细胞凋亡小体的自体及同种异体DC刺激的T细胞对肺癌细胞和乳腺癌细胞系MCF-7的杀伤作用.结果 骨髓细胞诱生的自体及同种异体DC负载肿瘤抗原后,均具有刺激T淋巴细胞增殖的能力,负载肿瘤抗原的自体及异体DC激活的T淋巴细胞后均可杀伤两种靶细胞,T细胞对MCF-7的杀伤力明显低于对患者肺癌细胞的杀伤力. 结论人自体或异体DC体外负载细胞性肿瘤抗原后,可有效地刺激T淋巴细胞的增殖,产生特异性肿瘤杀伤作用.     

HBcAg-pulsed dendritic cell vaccine induces Th1 polarization and production of hepatitis B virus-specific cytotoxic T lymphocytes

Aim:  Dendritic cells (DCs) pulsed with HBsAg efficiently reverse the immune tolerance to hepatitis B virus (HBV) and induce HBV-specific cytotoxic T lymphocyte (CTL) responses in transgenic mice and healthy volunteers. However, it is not clear whether HBV core antigen (HBcAg)-pulsed DCs can effectively induce CD4⁺ helper T cells polarization into Th1, which contribute to the induction and maintenance of HBV-specific CD8⁺ T cells in chronic hepatitis B (CHB) patients. To address this issue, we conducted this study and investigated whether HBcAg-pulsed DCs could polarize Th1 cells and induce an HBcAg-specific CTL response.
Methods:  HBcAg-pulsed DCs were generated from 21 CHB patients. The capacity of the HBcAg-pulsed DC vaccine to stimulate CD4⁺ and CD8⁺ T cells to produce IFN-γ and IL-4 was estimated by intercellular cytokine staining, and the HBcAg-pulsed DCs derived from 10 humam leucocyte antigen (HLA)-A2⁺ CHB patients were tested for the induction of HBV-specific CTLs from autologous T cells by pentamer staining. The cytotoxicity of these CTLs was evaluated in vitro by flow cytometry.
Results:  The HBcAg-pulsed DCs derived from CHB patients exhibited a stronger capacity to stimulate autologous CD4⁺ and CD8⁺ T cells to release IFN-γ rather than IL-4, which could induce HBV core 18-27 specific CTLs, suggesting a specific cytotoxicity against T2 cells that had been loaded with the HBV core 18-27 peptide in vitro .
Conclusion:  HBcAg-pulsed DC vaccine derived from CHB patients efficiently induced autologous T cell polarization to Th1 and generation of HBV core 18-27 specific CTLs.     

Enhancement of CTLs induced by DCs loaded with ubiquitinated hepatitis B virus core antigen

AIM: To investigate whether hepatitis B virus (HBV) could induce a hepatitis B virus core antigen (HBcAg)-specific cytotoxic T lymphocyte (CTL) response in vitro by dendritic cells (DCs) transduced with lentiviral vector-encoding ubiquitinated hepatitis B virus core antigen (LV-Ub-HBcAg).METHODS: Recombinant LV-Ub-HBcAg were transfected into highly susceptible 293 T cells to obtain high virus titres. Bone marrow-derived DCs isolated from BALB/c mice were cultured with recombinant granulocyte-macrophage colony-stimulating factor and recombinant interleukin (IL)-4. LV-Ub-HBcAg, lentiviral vector-encoding hepatitis B virus core antigen (LV-HBcAg), lentiviral vector (LV) or lipopolysaccharide were added to induce DC maturation, and the DC phenotypes were analyzed by flow cytometry. The level of IL-12 in the supernatant was detected by enzyme-linked immunosorbent assay (ELISA). T lymphocytes were proliferated using Cell Counting Kit-8. DCs were cultured and induced to mature using different LVs, and co-cultured with allogeneic T cells to detect the secretion levels of IL-2, IL-4, IL-10 and interferon-γ in the supernatants of T cells by ELISA. Intracellular cytokines of proliferative T cells were analyzed by flow cytometry, and specific CTL activity was measured by a lactate dehydrogenase release assay.RESULTS: LV-Ub-HBcAg-induced DCs secreted more IL-12 and upregulated the expression of CD80, CD86 and major histocompatibility class II. DCs sensitised by different LVs effectively promoted cytokine secretion; the levels of IL-2 and interferon-γ induced by LV-Ub-HBcAg were higher than those induced by LV-HBcAg. Compared with LV-HBcAg-transduced DCs, LV-Ub-HBcAg-transduced DCs more efficiently stimulated the proliferation of T lymphocytes and generated HBcAg-specific cytotoxic T lymphocytes.CONCLUSION: LV-Ub-HBcAg effectively induced DC maturation. The mature DCs efficiently induced T cell polarisation to Th1 and generated HBcAg-specific CTLs.     

Dendritic cells from chronic hepatitis B patients can induce HBV antigen-specific T cell responses

AIM: To determine whether dendritic cells (DCs) from chronic hepatitis B patients could induce HBV antigen-specific T cell responses or not. METHODS: DCs were generated from peripheral blood mononuclear cells of patients with chronic hepatitis B (CHB) infection and healthy donors. We compared the phenotypes of these DCs and their ability to secrete cytokines and to participate in mixed lymphocyte reactions. In addition, autologous lymphocytes were cultured with DCs loaded with HBV core region peptide HBcAg8-27, an epitope recognized by cytotoxic T lymphocytes (CTL), and bearing human leucocyte antigen (HLA)-A2 for 10 d. Cytokine secretion and lytic activity against peptide-pulsed target cells were assessed. RESULTS: DCs with typical morphology were generated successfully by culturing peripheral blood mononuclear cells (PBMCs) from CHB patients with AIM-V containing GM-CSF and IL-4. Compared with DCs from normal donors, the level of CD80 expressed in DCs from CHB patients was lower, and DCs from patients had lower capacity of stimulate T cell proliferation. When PBMCs isolated from patients with chronic or acute hepatitis B infection and from normal donors were cocultured with HBcAg18-27 peptide, the antigen-specific memory response of PBMCs from acute hepatitis B patients was stronger than that of PBMCs from chronic hepatitis B patients or normal donors. PBMCs cocultured with DCs treated with HBcAg18-27 CTL epitope peptide induced an antigen-specific T cell reaction, in which the level of secreted cytokines and lytic activity were higher than those produced by memory T cells. CONCLUSION: DCs from patients with CHB can induce HBV antigen-specific T cell reactions, including secretion of cytokines essential for HBV clearance and for killing cells infected with HBV.     

慢性乙型肝炎患者外周血树突状细胞诱导特异性T淋巴细胞应答

目的 探讨慢性乙型肝炎患者外周血树突状细胞(Dc)是否诱导特异性T细胞应答。方法(1)将研究对象分为慢性乙型肝炎患者组、急性乙型肝炎痊愈组、健康志愿者组,分离各组研究对象的外周血单个核细胞(PBMC),细胞内细胞因子染色方法检测其对细胞毒性T淋巴细胞(CTL)特异表位多肽乙型肝炎病毒核心抗原(HBcAg)18-27的记忆性免疫应答;(2)培养慢性乙型肝炎患者DC,将负载有乙型肝炎抗原表位多肽的DC诱导特异的T细胞应答。采用细胞内细胞因子染色方法检测诱导的T细胞分泌的细胞因子,乳酸脱氢酶释放法测定诱导的T细胞杀伤活性。结果(1)急性乙型肝炎患者PBMC对HBcAg 18-27 CTL特异表位多肽存在记忆的免疫应答,其分泌干扰素-γ的CD8+T细胞占CD8+T细胞总数的(4.3±2.5)％,分泌白细胞介素-2的占总细胞数的(4.8±2.2)％,分泌肿瘤坏死因子-α占总细胞数的(4.6±2.3)％。而慢性乙型肝炎患者和健康志愿者对其记忆应答很低,与急性乙型肝炎患者比较差异有显著性,t值为2.508-3.305,P<0.05。(2)用多肽共孵育过的慢性乙型肝炎患者DC多次诱导的T细胞慢性乙型肝炎患者组,加肽孵育的靶细胞比例为30:1、10:1、3:1时,其杀伤率分别为(57.0±20.3)％、(49.5±20.2)％、(21.8±12.9)％,均高于对照组,表明慢性乙型肝炎患者DC可以诱导特异的T     

前列腺素E1抑制慢性乙型重型肝炎树突状细胞成熟及CD4~+/CD8~+T细胞活性的观察

目的研究前列腺素E1对慢性乙型重型肝炎树突状细胞成熟及CD4+/CD8+T细胞活性的影响。方法抽取前列腺素E1治疗10 d前后的慢性乙型重型肝炎患者外周静脉血,密度梯度离心法分离淋巴细胞,贴壁培养获得PBMC,经重组人白细胞介素4(rhIL-4)、重组人粒-巨噬细胞集落刺激因子(rhGM-CSF)、加或不加前列腺素E1刺激培养8 d获得树突细胞(DC)。经流式细胞仪检测DC表达的HLA-DR、CD83、CD86,ELISA测定分泌的IFNγ、IL-12p70。悬浮T细胞部分检测CD4+/CD8+T细胞比例及其细胞表面CD69、HLA-DR表达;部分经IL-2培养,用于检测DC体外诱导的T淋巴细胞毒活性。结果前列腺素E1治疗慢性乙型重型肝炎,对患者CD4+/CD8+T细胞比例无明显影响,可抑制CD4+/CD8+T细胞活化分子CD69、HLA-DR的表达;前列腺素E1体外培养的DC低表达HLA-DR、CD83、CD86,分泌IFNγ、IL-12p70均下降,体外诱导的自体淋巴细胞毒活性减弱,与未加用前列腺素E1比较差异有统计学意义(P<0.01)。结论前列腺素E1治疗慢性乙型重型肝炎,可抑制CD4+/CD8+T细胞活化;体外培养可抑制DC成熟,诱导减弱自体淋巴细胞毒活性。     

慢性乙型肝炎病毒感染产妇的胎儿脐带血树突状细胞的表型及功能

目的探讨孕妇慢性乙型肝炎病毒(HBV)感染对其胎儿脐血的树突状细胞(DC)的表型和功能的影响,并与健康胎儿、健康成人及成人慢性HBV感染者进行对比研究。方法体外分离慢性HBV 感染产妇及健康产妇胎儿脐带血、健康成人及慢性乙型肝炎患者外周血单个核细胞进行树突状细胞转化,行流式细胞术对其表型进行分析,通过交叉混合淋巴细胞培养和DC培养上清液白细胞介素(IL)-12检测来分析DC的功能。结果慢性HBV感染产妇脐血来源DC的CD 80、CD 83的表达显著低于健康胎儿组、健康成人组、成人慢性HBV感染组,CD14的表达则显著高于此三组,P值均<0.0 5;慢性HBV感染产妇脐带血DC分泌的IL-12水平也明显低于健康产妇、健康成人组及慢性乙型肝炎患者(P<0.05);促异体T淋巴细胞增殖能力的强弱依次为健康成人DC-健康脐血T淋巴细胞>健康成人DC-健康成人异体T淋巴细胞>健康脐血DC-异体健康脐血T淋巴细胞>健康脐血DC-健康成人T淋巴细胞>孕母HBV感染脐血DC-健康脐血T淋巴细胞>孕母HBV感染脐血DC-健康异体成人T淋巴细胞。结论慢性HBV感染产妇胎儿脐血DC的成熟和功能显著低于健康胎儿脐血DC、健康成人甚至慢性乙型肝炎患者外周血DC。     

Cellular immune responses in hepatitis B virus e antigen negative chronic hepatitis B

The immunopathogenesis of hepatitis B e antigen (HBeAg) negative chronic hepatitis B (CHB) virus (HBV) infection has not been adequately investigated. We studied the cellular immune responses of peripheral lymphocytes using proliferating assays, intracellular cytokine staining (ICS) and ELISPOT interferon-gamma (IFN-gamma) assays after non-specific and specific stimulation with whole HBV proteins and synthetic peptides. Thirty patients with HBeAg negative CHB, eleven HBsAg inactive carriers, nine patients with acute hepatitis B and 22 healthy controls were included in the study. Patients with HBeAg negative CHB demonstrated an increased number of peripheral CD8+ T cells while their peripheral blood mononuclear cells showed increased proliferation after in vitro stimulation with overlapping hepatitis B core derived peptides and an envelope derived epitope (HBs 182-191 aa), similar to those observed in acute hepatitis B. Using ICS, we found an expanded population of IFN-gamma producing T lymphocytes, CD4+ and CD8+, after non-specific stimulation, in HBeAg negative CHB compared to all other groups. HBeAg negative CHB and acute hepatitis B patients had a similarly increased number of core specific T cells measured by the IFN-gamma assays. Inactive HBsAg carriers showed minimal proliferative responses overall while they exhibited an increased number of envelope specific effector T cells (measured by ICS). In conclusion, we showed that overall CD4+ T cell responses from patients with HBeAg negative CHB were comparable to those of acute hepatitis B, while inactive HBsAg carriers despite their limited proliferative capacity the effector activity of their peripheral T cells was maintained.     

Functional analysis of peripheral blood lymphocytes isolated from patients with chronic hepatitis type B

Cell-mediated immunity, evaluated by lymphocyte proliferation and expression of the activation antigen interleukin-2 receptor in response to mitogens such as phytohemagglutinin and concanavalin-A, has been reported to be defective in chronic hepatitis B virus carriers. However, no definite conclusion on the functional state of T cells from these patients can be drawn. In the present study, we have investigated the expression of a wide set of lymphoid activation molecules as well as the proliferative response of peripheral blood lymphocytes isolated from patients with chronic hepatitis type B afterin vitro stimulation with monoclonal antibodies to both the T-cell receptor-CD3 complex and the CD2 molecule, which are the two main T-cell activation pathways. Our findings show that peripheral T lymphocytes from patients with chronic hepatitis type B express the activation antigens 4F2 molecule, interleukin-2 receptor, and activation inducer molecule (AIM) antigen, and proliferate normally after specific stimulation through either the T-cell receptor-CD3 complex or the CD2 molecule. These results suggest that the peripheral blood T cells of patients with chronic hepatitis B are fully operative and functionally competentin vitro.This work was supported in part by a grant from the INSALUD (FISS 89/0068).     

DC-SIGN在慢性乙型肝炎病毒感染时树突状细胞成熟活化中的作用

目的研究慢性HBV感染时,DC-SIGN在树突状细胞（DC）成熟和活化中介导的作用。方法将α-甘露糖苷酶抑制剂-基夫碱作用于HepG2.2.15细胞,收获上清中的高甘露糖型HBV颗粒,并于第5 d加入到外周血单核细胞衍生的DC培养基中,培养至第7 d,采用流式细胞仪检测DC表面CDla、CD83、CD80、CD86、HLA-DR分子的表达,MTT法检测DC刺激淋巴细胞增殖的能力,ELISA法检测DC分泌IL-12的水平。结果高甘露糖型HBV组,与天然的HBV组相比,DC表面CDla、CD83、CD80、CD86、HLA-DR分子的表达增加,分泌IL-12的水平升高,刺激同种异体淋巴细胞增殖的能力亦明显增强,且上述效应均可被DC-SIGN特异性抗体所阻断。结论 DC-SIGN识别高甘露糖型HBV后可以促进DC的成熟和活化,天然的HBV可能利用α-甘露糖苷酶参与的去甘露聚糖修饰来逃避DC-SIGN的识别,从而诱导DC功能的缺陷。