エキソソームを利用したデリバリーキャリアの開発を目的とした体内動態および製剤学的特性の評価

京都大学0048新制・課程博士博士(薬科学)甲第21345号薬科博第95号新制||薬科||10(附属図書館)京都大学大学院薬学研究科薬科学専攻(主査)教授 髙倉 喜信, 教授 小野 正博, 教授 山下 富義学位規則第4条第1項該当Doctor of Pharmaceutical SciencesKyoto UniversityDFA

Macrophage-dependent clearance of systemically administered B16BL6-derived exosomes from the blood circulation in mice

Previous studies using B16BL6-derived exosomes labelled with gLuc–lactadherin (gLuc-LA), a fusion protein of Gaussia luciferase (a reporter protein) and lactadherin (an exosome-tropic protein), showed that the exosomes quickly disappeared from the systemic circulation after intravenous injection in mice. In the present study, the mechanism of rapid clearance of intravenously injected B16BL6 exosomes was investigated. gLuc-LA-labelled exosomes were obtained from supernatant of B16BL6 cells after transfection with a plasmid DNA encoding gLuc-LA. Labelling was stable when the exosomes were incubated in serum. By using B16BL6 exosomes labelled with PKH26, a lipophilic fluorescent dye, it was demonstrated that PKH26-labelled B16BL6 exosomes were taken up by macrophages in the liver and spleen but not in the lung, while PKH26-labelled exosomes were taken up by the endothelial cells in the lung. Subsequently, gLuc-LA-labelled B16BL6 exosomes were injected into macrophage-depleted mice prepared by injection with clodronate-containing liposomes. The clearance of the intravenously injected B16BL6 exosomes from the blood circulation was much slower in macrophage-depleted mice than that in untreated mice. These results indicate that macrophages play important roles in the clearance of intravenously injected B16BL6 exosomes from the systemic circulation

Exosomal microRNAs as potential circulating biomarkers in gastrointestinal tract cancers: a systematic review protocol

Abstract Background Metastasis is the most frequent type of recurrence in gastrointestinal (GI) cancers, and there is an emerging potential for new diagnostic and therapeutic approaches, especially in the cases of metastatic GI carcinomas. The expression profiles of circulating exosomal microRNAs are of particular interest as novel non-invasive diagnostic and prognostic biomarkers for improved detection of GI cancers in body fluids, especially in the serum of patients with recurrent cancers. The aim of this study is to systematically review primary studies and identify the miRNA profiles of serum exosomes of GI cancers. Methods and design This systematic review will be reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidance. Relevant studies will be identified through a comprehensive search of the following main electronic databases: PubMed, Web of Science, Embase, Scopus, and Google Scholar, with no language restrictions (up to July 2017). Full copies of articles will be identified by a defined search strategy and will be considered for inclusion against pre-defined criteria. The quality assessment of the included studies will be performed by the Newcastle-Ottawa Scale (NOS). Data will be analyzed using Stata software V.12. Publication bias will be assessed by funnel plots, Beggs’ and Eggers’ tests. The levels of evidence for primary outcomes will be evaluated using the GRADE criteria. Discussion The analysis of circulating exosomal miRNA profiles provides attractive screening and non-invasive diagnostic tools for the majority of solid tumors including GI cancers. There is limited information regarding the relationship between serum exosomal miRNA profiles and the pathological condition of patients with different GI cancers. Since there is no specific biomarker for GI cancers, we aim to suggest a number of circulating exosomal miRNA candidates as potential multifaceted GI cancer biomarkers for clinical utility. Systematic review registration PROSPERO CRD4201705712