Piccioli Diego, Tavarini Simona, Nuti Sandra, Colombatto Piero, Brunetto Maurizia, Bonino Ferruccio, Ciccorossi Pietro, Zorat Francesca, Pozzato Gabriele, Comar Consuelo, Abrignani Sergio, Wack Andreas
Immunology and Virology Department, Chiron Vaccines Research Center, via Fiorentina 1, 53100 Siena, Italy.
J Hepatol. 2005 Jan;42(1):61-7. doi: 10.1016/j.jhep.2004.09.014.
BACKGROUND/AIMS: Dendritic cells (DCs) play a key role in immune responses through antigen presentation and cytokine secretion. Hepatitis C virus (HCV) is able to escape elimination by the immune system and often establishes a chronic infection. To investigate whether DC dysfunction is involved in this process, we have studied monoycte-derived DCs (Mo-DCs) and plasmacytoid DCs (pDCs), which produce large amounts of IFN-alpha, from chronic HCV patients and healthy donors.
We have assessed TNF-alpha and IFN-alpha production by pDCs using intracellular staining after total PBMCs stimulation with unmethylated CG dinucleotides (CpGs). The induction of allogeneic T cell proliferation by immature Mo-DCs was measured using the MLR assay. The up-regulation of maturation markers and the production of TNF-alpha in response to LPS were analyzed using flow cytometry and ELISA, respectively.
We have detected comparable frequencies of pDCs producing TNF-alpha and IFN-alpha in both chronic HCV patients and healthy donors and we have found that immature Mo-DCs from both patients and donors similarly induce allogeneic T cell proliferation and mature and secrete TNF-alpha in response to LPS.
Our results demonstrate that both pDC and Mo-DCs are not impaired in HCV infected patients.
背景/目的：树突状细胞（DCs）通过抗原呈递和细胞因子分泌在免疫反应中发挥关键作用。丙型肝炎病毒（HCV）能够逃避被免疫系统清除，并常常建立慢性感染。为了研究DC功能障碍是否参与这一过程，我们研究了来自慢性HCV患者和健康供体的单核细胞衍生DCs（Mo-DCs）和浆细胞样DCs（pDCs），后者可产生大量的IFN-α。
在用未甲基化的CG二核苷酸（CpGs）刺激全外周血单个核细胞（PBMCs）后，我们通过细胞内染色评估pDCs产生TNF-α和IFN-α的情况。使用混合淋巴细胞反应（MLR）测定法测量未成熟Mo-DCs对同种异体T细胞增殖的诱导作用。分别使用流式细胞术和酶联免疫吸附测定（ELISA）分析成熟标志物的上调情况以及对脂多糖（LPS）反应时TNF-α的产生情况。
我们在慢性HCV患者和健康供体中检测到产生TNF-α和IFN-α的pDCs频率相当，并且我们发现来自患者和供体的未成熟Mo-DCs同样能诱导同种异体T细胞增殖，并且在对LPS反应时成熟并分泌TNF-α。
我们的结果表明，在HCV感染患者中，pDC和Mo-DCs均未受损。
