CD40配体-受体载体介导的CpG ODN靶向脐血B淋巴细胞的特异传递及其免疫效应(英文)

Delivery and immunologic efficacy of CpG ODN targeting B lymphocytes of umbilical cord blood by CD40 ligand-receptor-mediated carrier

背景:CpG寡核苷酸是一种高效低毒的免疫佐剂,在许多疾病的基因治疗中具有广阔的应用价值,但存在种属和细胞特异性,细胞摄取率低,易被酶降解,成为临床应用的障碍。目的:拟验证CpG寡核苷酸通过CD40配体-受体载体系统对脐血B淋巴细胞特异靶向传递及其免疫效应的增强作用。设计、时间及地点:观察对比实验,于2004-04/2007-10在广州暨南大学附属第一医院血液科、儿科完成。材料:取健康新生儿的肝素抗凝新鲜脐血,事先征得父母知情同意并获医院伦理委员会审核批准。方法:制备CD40配体-碳二亚胺-多聚左旋赖氨酸-CpG寡核苷酸交联复合物,与脐血单个核细胞共培养。分别于24,48,72,96h应用流式细胞仪检测单个核细胞对FAM标记CpG寡核苷酸的摄取率及平均摄入强度;培养96h后用直接免疫荧光标记法标记CD19,CD20,CD22单抗,以流式细胞仪检测阳性表达率;细胞悬液加入96孔板,3组分别加入CD40配体-碳二亚胺-多聚左旋赖氨酸-CpG寡核苷酸、单纯CpG寡核苷酸及ddH2O,培养92h,以四甲基偶氮唑盐比色法测细胞增殖能力;以酶联免疫吸附法测以上3组细胞培养上清IgG水平。主要观察指标:单个核细胞对CpG寡核苷酸的摄取率及平均摄入强度,淋巴细胞亚群的表达,细胞增殖能力,培养上清IgG水平。结果:与单纯CpG寡核苷酸未交联组相比,单个核细胞对交联复合物摄取率更高(>98%),达摄取峰值时间更早。共培养后CD19+,CD22+,CD20+细胞表达升高,细胞增殖量及上清IgG水平均高于对照组(P<0.05)。结论:CD40配体-受体载体系统有助于CpG寡核苷酸特异高效的B细胞靶向投递,并增强其免疫效应。

BACKGROUND： CpG oligodeoxynucleotide （ODN） is a type of highly effective immune adjuvant with low toxicity, which has an extensive application in gene therapy for many diseases. However, the specificity for species and cells leading to low uptake by cells and degradation by nuclease blocks its clinical application. OBJECTIVE： To explore the specific delivery and its immunologic efficacy of CpG ODN targeting B lymphocytes of umbilical cord blood by CD40 ligand-receptor-mediated carrier system. DESIGN, TIME AND SETTING： An observation and control experiment was performed at the Department of Hematology, and Department of Pediatric, the First Affiliated Hospital of Jinan University from April 2004 to October 2007. MATERIALS： Fresh umbilical cord blood with heparin was obtained from healthy, natal infant. Informed consent was obtained from his parents, and the experiment was approved by the hospital Ethics Committee. METHODS： CD40 ligand （CD40L）-EDC-PLL-CpG ODN conjugated complex was prepared. Mononuclear cells （MNCs） from umbilical cord blood were co-cultured with conjugated complexes. Uptake rate, mean fluorescence intensity of FAM marked CpG ODN, expressions of MNCs, proliferations of lymphocytes and the IgG levels of culture supernatants were detected by flow cytometry, fluorescence techniques, MTT assay and ELISA, respectively. MAIN OUTCOME MEASURES： The uptake rate, the mean fluorescence intensity of CpG ODN by MNCs, subgroups and proliferations of lymphocytes, and IgG levels of culture supernatants. RESULTS： Compared to the pure CpG ODN group, the uptake rate of the conjugated complexes group was higher （〉98%）, the peak level of up-taking occurred earlier, and intracellular fluorescence intensity maintained much more stable. Expressions of CD19^＋, CD22^＋, and CD20^＋ was increased, A value and IgG levels in supernatants were all higher than that of the control group. CONCLUSION： CD40 ligand-receptor-mediated carrier system is helpful for CpG ODN delivery targeting to B lymphocyte, enhancing its immunological efficiency.