Neural cell–cell and cell–substrate adhesion through N-cadherin, N-CAM and L1

Abstract

In this study neural (N)-cadherin, neural cell adhesion molecule (N-CAM) and L1 proteins and their antibody equivalents were covalently immobilized on a polyethylene-imine (PEI)-coated glass surface to form neuron-adhesive coatings. Impedance sensing and (supplementary) image analysis were used to monitor the effects of these CAMs. Immobilization of high concentrations of both N-cadherin protein and antibody led to good adhesion of neurons to the modified surface, better than surfaces treated with 30.0 and 100.0 µg ml(-1) N-CAM protein and antibody. L1 antibody and protein coating revealed no significant effect on neuronal cell-substrate adhesion. In a second series of combinatorial experiments, we used the same antibodies and proteins as medium-additives to inhibit cell-cell adhesion between neurons. Adhesion of neurons cultured on N-cadherin protein or antibody-modified surfaces was lowered by the addition of a soluble N-cadherin protein and antibody to the culturing medium, accelerating neuronal aggregation. The presence of a soluble N-CAM antibody or protein had no effect on the adhesion of neuronal cells on a N-cadherin protein-modified surface. On a N-cadherin antibody-coated surface, the addition of a soluble N-CAM protein led to cell death of neurons after 48 h, while a N-CAM antibody had no effect. In the presence of a soluble N-cadherin protein and antibody the aggregation of neurons was inhibited, both on N-CAM protein and N-CAM antibody-modified surfaces. Neurons cultured on immobilized antibodies were less affected by the addition of soluble CAM blockers than neurons cultured on immobilized proteins, indicating that antibody-protein bonds are more stable compared to protein-protein bonds.

Retrograde transport defects inMunc18-1null neurons explain abnormal Golgi morphology

“…To understand whether the abnormal Golgi morphology affects Golgi function, we examined the expression levels and localisation of two proteins that are trafficked through the Golgi: celladhesion protein N-Cadherin and Neurotrophin receptor Tropomyosin Receptor Kinase B (TrkB) (Fig4. A-B) (Klein et al, 1991;Wiertz et al, 2011). In Munc18-1 KO neurons, the N-Cadherin staining intensity in the TGN46-positive area was comparable to WT neurons (Fig.…”

Loss of MUNC18‐1 leads to retrograde transport defects in neurons

“…To understand whether the abnormal Golgi morphology affects Golgi function, we examined the expression levels and localisation of two proteins that are trafficked through the Golgi: cell‐adhesion protein N‐Cadherin and Neurotrophin receptor Tropomyosin Receptor Kinase B (TrkB) (Figure 4. A‐B) (Klein et al, 1991; Wiertz et al, 2011). In Munc18‐1 KO neurons, the N‐Cadherin staining intensity in the TGN46‐positive area was comparable to WT neurons (Figure 4c), while the TrkB intensity was ~% lower (Figure 4d).…”

“…To understand whether the abnormal Golgi morphology affects Golgi function, we examined the expression levels and localisation of two proteins that are trafficked through the Golgi: cell-adhesion protein N-Cadherin and Neurotrophin receptor Tropomyosin Receptor Kinase B (TrkB) (Figure 4. A-B) (Klein et al, 1991;Wiertz et al, 2011).…”

Self-assembled chitin nanofiber templates for artificial neural networks

“…Controlled adhesion of neural cells to substrates in vitro has attracted attention due to their potential application for neuroscience investigations, 1 artificial neural networks, 2,3 and neuroelectronics. 4,5 Neuron attachment in well-defined networks is necessary for cell survival and is important for ensuring and examining cell-cell communications responsible for neural signalling. 6,7 However, it is difficult to produce a network that satisfies cell attachment and long-term viability, due to neuron degeneration at low culture density.…”