Yoon Ok Jang1†, Hee‑Sung Ahn2†, Thuy Nguyen Thi Dao1, JeongYeon Hong3,4, Wangyong Shin5, Young‑Min Lim5, Sun Ju Chung5, Jae‑Hong Lee5, Huifang Liu1, Bonhan Koo1, Myoung Gyu Kim1, Kyunggon Kim3,4*, Eun‑Jae Lee5* and Yong Shin1*
1Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea.
2Department of Convergence Medicine, Asan Medical Center, Seoul 05505, Republic of Korea.
3Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Republic of Korea.
4Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea.
5Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea.
†Yoon Ok Jang and Hee-Sung Ahn these authors equally contributed to this study.
*Correspondence: Kyunggon Kim, Eun‑Jae Lee, Yong Shin
Background: Brain-derived exosomes released into the blood are considered a liquid biopsy to investigate the pathophysiological state, reflecting the aberrant heterogeneous pathways of pathological progression of the brain in neurological diseases. Brain-derived blood exosomes provide promising prospects for the diagnosis of neurological diseases, with exciting possibilities for the early and sensitive diagnosis of such diseases. However, the capability of traditional exosome isolation assays to specifically isolate blood exosomes and to characterize the brain-derived blood exosomal proteins by high-throughput proteomics for clinical specimens from patients with neurological diseases cannot be assured. We report a magnetic transferrin nanoparticles (MTNs) assay, which combined transferrin and magnetic nanoparticles to isolate brain-derived blood exosomes from clinical samples.
Methods: The principle of the MTNs assay is a ligand-receptor interaction through transferrin on MTNs and transferrin receptor on exosomes, and electrostatic interaction via positively charged MTNs and negatively charged exosomes to isolate brain-derived blood exosomes. In addition, the MTNs assay is simple and rapid (< 35 min) and does not require any large instrument. We confirmed that the MTNs assay accurately and efficiently isolated exosomes from serum samples of humans with neurodegenerative diseases, such as dementia, Parkinson's disease (PD), and multiple sclerosis (MS). Moreover, we isolated exosomes from serum samples of 30 patients with three distinct neurodegenerative diseases and performed unbiased proteomic analysis to explore the pilot value of brain-derived blood protein profiles as biomarkers.
Results: Using comparative statistical analysis, we found 21 candidate protein biomarkers that were significantly different among three groups of neurodegenerative diseases.
Conclusion: The MTNs assay is a convenient approach for the specific and affordable isolation of extracellular vesicles from body fluids for minimally-invasive diagnosis of neurological diseases.