Fox H B, De Togni P, McMahon G, Levy S B, Robinson J S, Karnovsky M J, Babior B M
Blood. 1987 May;69(5):1394-400.
Escherichia coli minicells containing the plasmid pSC101 (approximately 10 kb) or pBR322 (approximately 4 kb) were opsonized and incubated with human neutrophils. The neutrophils responded to the minicells as they would to native E coli: they ingested the minicells, discharged their granule contents into the minicell-containing phagosomes, and expressed a respiratory burst. After one hour of incubation, the fate of the ingested plasmid DNA was examined. No DNA degradation was detected by trichloroacetic acid precipitation or agarose gel electrophoresis. Moreover, when pBR322 recovered from ingested minicells was transformed into E coli, no mutations in either of the antibiotic resistance genes carried by the plasmid were detected out of many thousand transformants screened. These findings confirm the surprisingly limited effect of neutrophils on ingested DNA.
含有质粒pSC101(约10 kb)或pBR322(约4 kb)的大肠杆菌微细胞经调理后与人中性粒细胞一起孵育。中性粒细胞对微细胞的反应与它们对天然大肠杆菌的反应相同:它们摄取微细胞,将其颗粒内容物释放到含有微细胞的吞噬体中,并表现出呼吸爆发。孵育一小时后,检查摄取的质粒DNA的命运。通过三氯乙酸沉淀或琼脂糖凝胶电泳未检测到DNA降解。此外,当从摄取微细胞中回收的pBR322转化到大肠杆菌中时,在筛选的数千个转化体中未检测到质粒携带的任何一个抗生素抗性基因发生突变。这些发现证实了中性粒细胞对摄取的DNA的影响出人意料地有限。