Engineering a Stable Synaptogenic Extracellular Matrix

Laila Al-Alwan, Markus Hellmund, Rainer Haag, Timothy Kennedy


Synapses are specialized sites of asymmetric cell – cell contact that mediate information transfer between neurons and their targets. Many proteins involved in the recruitment, organization and maintenance of synapses have been identified. Surprisingly, synaptic differentiation does not require a biological membrane surface. Instead, synaptic specializations can form quickly at sites of neurite adhesion to microspheres (beads) coated with synaptogenic proteins or even poly-lysine, a synthetic cationic polypeptide, raising the possibility that functional hemi-synaptic connections could be formed onto designer engineered surfaces. Previous studies examining the stability of synapses formed in brain onto poly-lysine coated beads found they were unstable, degraded, and ultimately replaced by a glial scar. Here, we address the capacity of an extreme biomimetic of poly-lysine, PGB50, a dendritic polyglycerol (dPG)-amine soft matter nanoparticle, to enhance synapse formation in long-term cultures of rat cortical neurons. Microbeads coated with PGB50 exhibit substantially enhanced synaptogenesis and synapse stability compared to poly-lysine. We propose that synaptogenic extracellular matrices could be used to engineer synaptogenic electrodes with enhanced neural-compatibility, reducing glial scaring and inflammation, and allowing for bi-directional communication with neurons through the formation of stable of synaptic specializations.


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Paper Citation

in Harvard Style

Al-Alwan L., Hellmund M., Haag R. and Kennedy T. (2016). Engineering a Stable Synaptogenic Extracellular Matrix . In - NEUROTECHNIX, ISBN , pages 0-0

in Bibtex Style

author={Laila Al-Alwan and Markus Hellmund and Rainer Haag and Timothy Kennedy},
title={Engineering a Stable Synaptogenic Extracellular Matrix},
booktitle={ - NEUROTECHNIX,},

in EndNote Style

TI - Engineering a Stable Synaptogenic Extracellular Matrix
SN -
AU - Al-Alwan L.
AU - Hellmund M.
AU - Haag R.
AU - Kennedy T.
PY - 2016
SP - 0
EP - 0
DO -