重组腺相关病毒2型转导人外周血单核细胞来源树突状细胞的研究

To find out the infection efficiency of recombinant adeno-as sociated virus 2-mediated exogenou s genes in human peripheral blood monocyte-derived dendritic cells(D Cs),the process of transfection wa s investigated by FITC-labeled rAA V2,and observed under confocal mic roscope.Newly separated dendritic cells were tranfected by rAAV2-luc and rAAV2-GFP at different MOI,and transfection efficiency were detec ted by luminometer for rAAV2-luc a nd flow cytometry for rAAV2-GFP.Th e results were elucidated in four different assay systems:(1)60min w as needed for rAAV2 to bind on den dritic cells,and got into cells in the following 10min;(2)the express ion of luc could be detected at th e MOI as low as 1×10~5v.g/cell,and the expression plateau was reached by the MOI of 10~6～10~7v.g/cell,furt her increase of MOI had no functio n on expression level;(3)transgene expression was detected after 48h, and maintained a higher expression level from 96h to 240h after infec tion;(4)7days postinfection of rAA V2-GFP,5%～18% dendritic cells were GFP positive. These data suggest th at rAAV2 vector can efficiently in fect monocyte-derived dendritic ce lls and mediate exogenous gene exp ression,and that the application o f rAAV2 as vector may be useful fo r gene transfer to dendritic cells in ex vivo immunotherapy.     

类SCC样甲氧西林敏感性金黄色葡萄球菌的基因组学分析

金黄色葡萄球菌(Staphylococcus aureus, S. aureus), 作为一种常见的致病菌常可导致严重感染性疾病. 金黄色葡萄球菌的主要特点是易产生耐药性. 临床上运用多重PCR方法对S. aureus耐药菌株进行分型. SCC作为一种mecA基因的转运载体, 介导金黄色葡萄球菌产生耐药性. 本研究报道了一株新甲氧西林敏感性金黄色葡萄球菌的全基因组序列信息, 即类SCC样MSSA463菌株, 经多重PCR方法, 该菌株被误鉴定为耐甲氧西林金黄色葡萄球菌, 结果与药敏结果相冲突. 为此, 运用焦磷酸测序方法完成了该菌株的全基因组测序, 并与已知金黄色葡萄球菌的基因组序列信息不同, 发现可读框(CZ049; AB037671)存在于attL, attR反向重复序列的临近下游. 这些结果提示, 在金黄色葡萄球菌与其他微生物之间可能存在一种水平基因转移, 并改变了金黄色葡萄球菌对药物的敏感性, 推测attL, attR反向重复序列可能作为外源性基因的插入部位而存在.