Frontiers in Bioengineering and Biotechnology (Jan 2021)

Maturation of Neural Cells Leads to Enhanced Axon-Extracellular Matrix Adhesion and Altered Injury Response

  • Xueying Shao,
  • Xueying Shao,
  • Xueying Shao,
  • Maja Højvang Sørensen,
  • Chao Fang,
  • Chao Fang,
  • Raymond Chuen Chung Chang,
  • Zhiqin Chu,
  • Yuan Lin,
  • Yuan Lin

DOI
https://doi.org/10.3389/fbioe.2020.621777
Journal volume & issue
Vol. 8

Abstract

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Although it is known that stronger cell-extracellular matrix interactions will be developed as neurons mature, how such change influences their response against traumatic injury remains largely unknown. In this report, by transecting axons with a sharp atomic force microscope tip, we showed that the injury-induced retracting motion of axon can be temporarily arrested by tight NCAM (neural cell adhesion molecule) mediated adhesion patches, leading to a retraction curve decorated with sudden bursts. Interestingly, although the size of adhesion clusters (~0.5–1 μm) was found to be more or less the same in mature and immature neurons (after 7- and 3-days of culturing, respectively), the areal density of such clusters is three times higher in mature axons resulting in a much reduced retraction in response to injury. A physical model was also adopted to explain the observed retraction trajectories which suggested that apparent adhesion energy between axon and the substrate increases from ~0.12 to 0.39 mJ/m2 as neural cell matures, in good agreement with our experiments.

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