Primary Adult Astrocytes Research Articles

Diminished LC3-Associated Phagocytosis by Huntington's Disease Striatal Astrocytes.

Background:In recent years the functions of astrocytes have shifted from conventional supportive roles to also include active roles in altering synapses and engulfment of cellular debris. Recent studies have implicated astrocytes in both protective and pathogenic roles impacting Huntington’s disease (HD) progression.Objective:The goal of this study is to determine if phagocytosis of cellular debris is compromised in HD striatal astrocytes.Methods:Primary adult astrocytes were derived from two HD mouse models; the fast-progressing R6/2 and slower progressing Q175. With the use of laser nanosurgery, a single astrocyte was lysed within an astrocyte network. The phagocytic response of astrocytes was observed with phase contrast and by fluorescence microscopy for GFP-LC3 transiently transfected cells.Results:Astrocyte phagocytosis was significantly diminished in primary astrocytes, consistent with the progression of HD in R6/2 and Q175 mouse models. This was defined by the number of astrocytes responding via phagocytosis and by the average number of vesicles formed per cell. GFP-LC3 was found to increasingly localize to phagocytic vesicles over a 20-min imaging period, but not in HD mice, suggesting the involvement of LC3 in astrocyte phagocytosis.Conclusion:We demonstrate a progressive decrease in LC3-associated phagocytosis in HD mouse striatal astrocytes.

Amyloid-β-induced chemokine production in primary human macrophages and astrocytes

In Alzheimer's disease (AD), chemotaxis might be responsible for attracting glial cells towards the neuritic plaque. Using primary monocyte-derived macrophages and primary adult astrocytes as a model, amyloid-beta (Aβ) (1–42) was able to stimulate the production, as measured by RT-PCR, of MIP-1α and MIP-1β mRNA in macrophages and MCP-1 in astrocytes. Cocultures showed in unstimulated as well as in Aβ-stimulated cells an increase in MIP-1α, MIP-1β and MCP-1 mRNA. ELISAs of supernatant samples of stimulated macrophages and astrocytes also showed an increase in MIP-1α and MIP-1β in macrophages and MCP-1 in astrocytes. Stimulated cocultures showed an increase in MIP-1α, MIP-1β and MCP-1 protein levels in contrast to unstimulated cocultures.