title: Estimation of the distribution of intravenously injected adipose tissue-derived stem cells labeled with quantum dots in mice organs through the determination of their metallic components by ICPMS.
abstract: Adipose tissue-derived stem cells (ASCs) have shown promise in cell therapy because of their ability to self-renew damaged or diseased organs and easy harvest. To ensure the distribution and quantification of the ASCs injected from tail vein, several whole-body imaging techniques including fluorescence optical imaging with quantum dots (QDs) have been employed, but they may suffer from insufficient sensitivity and accuracy. Here, we report quantitative distribution of ASCs in various organs (heart, lung, liver, spleen, and kidney) of mice, which were intravenously injected with QDs-labeled ASCs (QDs-ASCs), through the detection of QDs-derived metallic components by inductively coupled plasma mass spectrometry (ICPMS). For accurate and precise determination, each organ was harvested and completely digested with a mixture of HNO(3) and H(2)O(2) in a microwave oven prior to ICPMS measurement, which was equipped with a microflow injection system and a laboratory-made capillary-attached micronebulizer. After optimization, 16 elements including major components (Cd, Se, and Te) of QDs and essential elements (Na, K, Mg, Ca, P, S, Mn, Fe, Co, Cu, Zn, Se, Sr, and Mo) were successfully determined in the organs. As compared to untreated mice, QDs-ASCs-treated mice showed significantly higher levels of Cd and Te in all organs, and as expected, the molar ratio of Cd to Te in each organ was in good agreement with the molar composition ratio in the QDs. This result indicates that the increment of Cd (or Te) can be used as a tracer for calculating the distribution of ASCs in mice organs. As a result of the calculation, 36.8%, 19.1%, 0.59%, 0.49%, and 0.25% of the total ASCs injected were estimated to be distributed in the liver, lung, heart, spleen, and kidney, respectively.
authors.affiliation: Division of Nano-materials Science, EcoTopia Science Institute, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Takasaki
authors.forename: Masaki
authors.initials: M
authors.lastname: Watanabe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yukawa
authors.forename: Akhmad
authors.initials: A
authors.lastname: Sabarudin
authors.forename: Kazumi
authors.initials: K
authors.lastname: Inagaki
authors.forename: Noritada
authors.initials: N
authors.lastname: Kaji
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Okamoto
authors.forename: Manabu
authors.initials: M
authors.lastname: Tokeshi
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Miyamoto
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Noguchi
authors.forename: Tomonari
authors.initials: T
authors.lastname: Umemura
authors.forename: Shuji
authors.initials: S
authors.lastname: Hayashi
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Baba
authors.forename: Hiroki
authors.initials: H
authors.lastname: Haraguchi
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000818:Animals; D002417:Cattle; D005260:Female; D007275:Injections, Intravenous; D013058:Mass Spectrometry; D008670:Metals / Q000032:analysis*; D051379:Mice; D008810:Mice, Inbred C57BL; D057054:Molecular Imaging; D045663:Quantum Dots; D013234:Stem Cells / Q000166:cytology*; D014018:Tissue Distribution
chemical_list: D008670:Metals