International Journal of Nanomedicine (Mar 2020)
A Protein Corona Adsorbed to a Bacterial Magnetosome Affects Its Cellular Uptake
Abstract
Wenjia Lai,1,* Dan Li,2,3,* Qingsong Wang,4 Xiaohui Nan,2,3 Zhichu Xiang,2,3 Yan Ma,5 Ying Liu,2 Jiankui Chen,6 Jiesheng Tian,7 Qiaojun Fang2,3 1CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People’s Republic of China; 2CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People’s Republic of China; 3University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China; 4State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, People’s Republic of China; 5Aviation Service Department, Yantai Engineering & Technology College, Yantai 264000, People’s Republic of China; 6Clinical Laboratory, Affiliated Hospital of Academy of Military Medical Sciences, Beijing 100071, People’s Republic of China; 7State Key Laboratories for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing 100193, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jiesheng TianState Key Laboratories for Agrobiotechnology and College of Biological Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing 100193, People’s Republic of ChinaTel +86 10-62731440Email [email protected] Qiaojun FangCAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, No. 11 ZhongGuanCun Beiyitiao, Haidian District, Beijing 100190, People’s Republic of ChinaTel +86 10-82545562Email [email protected]: It is well known that when exposed to human blood plasma, nanoparticles are predominantly coated by a layer of proteins, forming a corona that will mediate the subsequent cell interactions. Magnetosomes are protein-rich membrane nanoparticles which are synthesized by magnetic bacteria; these have gained a lot of attention owing to their unique magnetic and biochemical characteristics. Nevertheless, whether bacterial magnetosomes have a corona after interacting with the plasma, and how such a corona affects nanoparticle–cell interactions is yet to be elucidated. The aim of this study was to characterize corona formation around a bacterial magnetosome and to assess the functional consequences.Methods: Magnetosomes were isolated from the magnetotactic bacteria, M. gryphiswaldense (MSR-1). Size, morphology, and zeta potential were measured by transmission electron microscopy and dynamic light scattering. A quantitative characterization of plasma corona proteins was performed using LC-MS/MS. Protein absorption was further examined by circular dichroism and the effect of the corona on cellular uptake was investigated by microscopy and spectroscopy.Results: Various serum proteins were found to be selectively adsorbed on the surface of the bacterial magnetosomes following plasma exposure, forming a corona. Compared to the pristine magnetosomes, the acquired corona promoted efficient cellular uptake by human vascular endothelial cells. Using a protein-interaction prediction method, we identified cell surface receptors that could potentially associate with abundant corona components. Of these, one abundant corona protein, ApoE, may be responsible for internalization of the magnetosome-corona complex through LDL receptor-mediated internalization.Conclusion: Our findings provide clues as to the physiological response to magnetosomes and also reveal the corona composition of this membrane-coated nanomaterial after exposure to blood plasma.Keywords: LC-MS/MS, cellular interaction, cellular uptake, biogenic magnetic nanoparticle
