Neuron-Glia Interactions in Neural Plasticity: Contributions of Neural Extracellular Matrix and Perineuronal Nets

Table 1

Cellular sources of the major PNNs components.

Name	Neurons		Astrocytes		Oligodendrocytes		NG2 glia		Citations
	In vitro	In vivo	In vitro	In vivo	In vitro	In vivo	In vitro	In vivo
HA	++	++	++	++	−	−	−	−	[49, 55, 74–76]
Aggrecan	++	++	++	−	−	−	−	−	[46–51]
Brevican	−	+^1	+++	+++	−	−	−	−	[55–57]
Neurocan	+++	+++	+^2	−	−	−	−	−	[46, 55, 60, 61]
Phosphacan	−	++	−	++	−	++	−	++	[55, 82, 83]
Versican	+^3	−	+^3	−	+++	+++	−	++	[46, 55, 63]
Tnr	++	++	+^4	−	++	++	−	++	[48–50, 55, 88, 89]
Tnc	−	+^5	+++	+++	−	−	−	−	[103–106]
Crtl1	−	+++	−	−	−	−	−	−	[48, 55, 98]
Bral2	−	+++	−	−	−	−	−	−	[48, 55, 98]
Semaphorin 3A	−	++	++	++	−	−	−	−	[76, 109–111]

Symbol +++ indicates the evidence for strong protein and/or mRNA expression, almost restricted to a certain cell type; symbol ++ indicates moderate expression under physiological conditions; + indicates weak or transient expression in a particular cellular subtype or under certain experimental conditions, indicated by superscript footnotes and described below. Dashes indicate the absence of evidence for cell type specific expression published so far.
¹Neurons of molecular layer of cerebellar cortex and by large excitatory deep cerebellar nuclei neurons [55].
²Astrocytic monolayers in culture [61].
³Neurons and astrocytes differentiated from embryonic stem cells [46].
⁴Type 2 but not type 1 astrocytes [89].
⁵Transient expression by neurons of spinal cord and hippocampus during development [103, 105].