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Label-free nanoscale optical metrology on myelinated axons in vivo.

ABSTRACT: In the mammalian nervous system, myelin provides electrical insulation for the neural circuit by forming a highly organized, multilayered thin film around the axon fibers. Here, we investigate the spectral reflectance from this subcellular nanostructure and devise a new label-free technique based on a spectroscopic analysis of reflected light, enabling nanoscale imaging of myelinated axons in their natural living state. Using this technique, we demonstrate three-dimensional mapping of the axon diameter and sensing of dynamic changes in the substructure of myelin at nanoscale. We further reveal the prevalence of axon bulging in the brain cortex in vivo after mild compressive trauma. Our novel tool opens new avenues of investigation by creating unprecedented access to the nanostructural dynamics of live myelinated axons in health and disease.

SUBMITTER: Kwon J

PROVIDER: S-EPMC5705720 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Label-free nanoscale optical metrology on myelinated axons in vivo.

Kwon Junhwan J Kim Moonseok M Park Hyejin H Kang Bok-Man BM Jo Yongjae Y Kim Jae-Hwan JH James Oliver O Yun Seok-Hyun SH Kim Seong-Gi SG Suh Minah M Choi Myunghwan M

Nature communications 20171128 1

In the mammalian nervous system, myelin provides electrical insulation for the neural circuit by forming a highly organized, multilayered thin film around the axon fibers. Here, we investigate the spectral reflectance from this subcellular nanostructure and devise a new label-free technique based on a spectroscopic analysis of reflected light, enabling nanoscale imaging of myelinated axons in their natural living state. Using this technique, we demonstrate three-dimensional mapping of the axon d ...[more]

PMID: 29184114

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