气道内注射负载卵白蛋白多肽的树突状细胞可诱导肺内炎症

Dendritic Cells Overloaded Antigens Injected Intratracheally Induce Lung Inflammation

目的探讨树突状细胞(DCs)作为免疫治疗载体气道内注射的可行性。方法取BALB/c小鼠骨髓单个核细胞,以重组小鼠粒-巨细胞集落刺激因子(rmGM-CSF)+重组小鼠白细胞介素4(rmIL-4)体外诱导培养DCs。经磁珠纯化后得到的DCs用卵白蛋白323-339氨基酸区(OVA323-339多肽)冲击24 h。DC-OVA组小鼠按每鼠2×106细胞数进行小鼠气道内接种。DC组小鼠以DCs直接进行气道内接种作为阴性对照。接种后次日起以1%OVA雾化,连续5 d。经典哮喘模型组小鼠采用经典OVA腹腔注射致敏及激发方法复制哮喘模型作为阳性对照。末次雾化后24 h处死小鼠,分析肺脏病理学表现、支气管肺泡灌洗液(BALF)中的细胞成分。结果 DC-OVA组小鼠肺内呈现小支气管及血管周围大量炎细胞浸润,杯状细胞增多,BALF中细胞数明显增多,血清中OVA-特异性IgE水平与经典复制哮喘模型组OVA-特异性IgE水平相似[(48.22±4.76)U/mL比(52.75±4.03)U/mL,P>0.05]。采用该方法复制的模型与采用经典方法复制的哮喘模型表现相似。DC组肺组织无明显的炎症,血清中的OVA-特异性IgE水平低于检测的敏感度。结论体外抗原负载后的DCs气道内注射具有活力并能有效递呈抗原,DCs可能作为免疫治疗的载体。

Objective To investigate the feasibility of dendritic cells （DCs） as vector of immunotherapy through intratracheal injection.Methods The DCs obtained from the bone marrow of BALB/c mice were cultured and isolated with CD11c-positive magnetic beads.Then DCs were overloaded with ovalbumin peptide 323-339（OVA 323-339） for 24 hours.The mice in the DC-OVA group were intratrachelly injected DCs overloaded with OVA 323-339 in dose of 2×106 cells per mouse.The mice in the negative control group were intratracheally injected with DCs untreated by OVA 323-339.On the second day,all mice were challenged with 1% OVA in PBS lasting for five days.The asthma animal model established by classic method was used for the positive control.Pathologic changes in lung and cell numbers in bronchoalveolar lavage fluid（BALF） were assayed 24 hours after challenged.Results Just like the lung tissues from the mice asthma models,the lung tissues from the mice instilled with DCs overloaded with allergen OVA 323-339 showed extensive inflammatory cells infiltration,most of which were eosinophils,neutrophils and lymphocytes.The lung tissues in the DC group showed no obvious inflammation.There were more cells in BALF in the DC-OVA group than that in the DC group.OVA-specific IgE in serum from the DC-OVA group was not significantly different from that in the mice asthma models [（48.22±4.76） U/mL vs.（52.75±4.03） U/mL,P0.05].Conclusion DCs overloaded antigen has the ability of transferring of antigen effectively and may be used as vectors of immunotherapy.