Loading…
Astrocytes (almost immobile) make up at least 50% of humans' brain and spinal cord cells. Astrocytes are essential for synapse formation (3). If they provide trophic support to neurons, one cannot remove them without catastrophic consequences [4].
Liddelow et al. 2020 Trends in Immunology 41: 820
However, astrocytes have been suggested to have immunological functions in both health and disease [19,20].
Castellanii & Schwartz 2020 Trends in immunology 41: 794
Astrocytes were shown to exert both pro- and anti-inflammatory signaling functions, depending on the context.
Castellanii & Schwartz 2020 Trends in immunology 41: 794
Astrocytes produce the inflammatory cytokine IL-1 beta, known to induce neuronal damage.
Castellanii & Schwartz 2020 Trends in immunology 41: 794
they can participate in leukocyte recruitment by releasing the chemokine C-C motif chemokine ligand 2 (CCL2)
Castellanii & Schwartz 2020 Trends in immunology 41: 794
CCL2 release was shown to be promoted by secretion of the alarmin IL-33 by damaged oligodendrocytes
Gadani et al. 2015 Neuron 85: 703-709
Ito et al. 2019 Nature 565: 246-250
astrocytes express innate immune receptors such as Toll-like receptors (TLRs) [8].
Castellanii & Schwartz 2020 Trends in immunology 41: 794
Heparin-binding EGF-like growth factor (HBEGF) is a trophic support molecule for astrocytes [9].
Liddelow et al. 2020 Trends in Immunology 41: 820
Astrocytes are the most abundant glial cell type in the mammalian CNS and interact with neurons, endothelial cells, microglia, oligodendrocytes, and other astrocytes [7]; these interactions lead to the formation of a complex multicellular cerebral network. In addition, they modify the blood–brain barrier (BBB) permeability, and recruitment of peripheral immune cells into the CNS [8].
Castellanii & Schwartz 2020 Trends in immunology 41: 794