2016 年 6 月 8 日	 	 日本機械学会北海道支部	  バイオメカニクス懇話会	 
第 23 回講演会	 	 （共催：日本機械学会北海道支部，日本機械学会バイオエンジニアリング部門「計測と力学̶
生体への応用̶」研究会，日本生体医工学会専門別研究会「バイオメカニクス研究会」）	 	 

主査	  大橋	  俊朗	 	 
下記の要領にて第 23 回講演会を開催いたします．本講演会は日本機械学会北海道支部
特別講演会，日本機械学会バイオエンジニアリング部門第 51 回「計測と力学-生体への応用-」研究会，日本生体医工学会専門別研究会「バイオメカニクス研究会」第 160回研究会と共催といたします．多数のご参加をお待ちしております．多数のご参加をお待ちしております．	 	 
記	 
日	  時：2016 年 6 月 24 日（金），11:00~12:00
場	  所：北海道大学大学院工学研究院・工学部	  大会議室 A1-17 室
http://www.eng.hokudai.ac.jp/building/?place=outer
講	  演：「Magnetic nanoparticles for new therapies and diagnosis」Prof. M. Ricardo Ibarra
Director, Instituto de Nanociencia de Aragón (INA) Universidad de Zaragoza, Spain
Professor, Laboratorio de Microscopias Avanzadas (LMA) Universidad de Zaragoza, Spain
Magnetic nanoparticles (MNPs) constitute nowadays a vast field of research due to thecurrent and expected application in nanobiomedicine. The potential MNPs stems from theintrinsic properties of their magnetic cores, combined with the functionality acquired under anappropriate coating. The capability for loading and targeted controlled release of drugs is oneof the main issues in cancer therapy (for recent reviews see [1,2]). The biofunctionalization of
the nanoparticles surface make them suitable for magnetic separation based on thebiomolecular recognition of biological moieties. New inmunomagnetic assays using magnetic
nanoparticles provides a new route to quantize the results in biosensors. The presence ofMNPs also perturb locally the hydrogen proton relaxation, this phenomenon is on the bases ofthe enhance MRI diagnostic using contrast agents. Targeting of these contrast agents could
detect angiogenesis processes at early stages.
In this talk a brief review of all these different applications will be depicted emphasizing

the application of electromagnetic waves in new therapies based on magnetic hyperthermia.
The case of dendritic cells (DCs) as main candidate for magnetic hyperthermia will bereported. Magnetic hyperthermia (MH) is based on the use of MNPs to selectively increase thetemperature of MNP-loaded target tissues when applying an alternating magnetic field (AMF)
in the range of radiofrequency. To date, all MH research has focused on heat generation in anattempt to elucidate the mechanisms for the death of MNP-loaded cells submitted to AMF.
However, recent in vitro studies have demonstrated the feasibility of inducing dramatic cell
death without increasing the macroscopic temperature during AMF exposure. Here, we showthat the cell death observed following AMF exposure, specifically that of MNPs loaded
dendritic cells (DCs) in culture, was caused by the release of toxic agents into the cell culture
supernatants and not due to a macroscopic temperature increase[3]. We performed MH in vitro
experiments to demonstrate that the supernatant of the cell culture following AMF exposure
was highly toxic when added to control unloaded DCs, as this treatment led to nearly 100%cell death. Therefore, our results demonstrate that heat is not the only agent responsible fortriggering cell death following MH treatment. This finding offers new perspectives for the useof DCs as the proverbial Trojan horse to vectorise MNPs to the target tumour area and theseresults further support the use of DCs as therapeutic agents against cancer when submitted toAMF. Furthermore, this discovery may help in understanding the mechanism of cell death
mediated by exposure to AMF.
[1] “Magnetic nanoparticles for drug delivery” M. Arruebo, R. Fernandez-Pacheco, M.R.
Ibarra and J. Santamaría. Nanotoday 2 (2007) 22[2] “Magnetic nanoparticles for cancer therapy” G.F: Goya, V. Grazu and M.R. Ibarra.
Current Nanoscience 4 (2008) 1-16
[3] “Induced cell toxicity originates dendritic cell death following magnetic hyperthermia
treatment” L Asín, G F Goya, A Tres & M R Ibarra. Cell Death and Disease 4, e596
doi:10.1038/cddis.2013.121 (http://www.nature.com/cddis)
問い合わせ先：大橋	  俊朗	  	  北海道大学大学院工学研究院人間機械システムデザイン部門
Tel&Fax: 011-706-6424, Email: ohashi@eng.hokudai.ac.jp