ALS/FTD-linked TBK1 deficiency in microglia induces an aged-like microglial signature and drives social recognition deficits in mice.

TANK-Binding Kinase 1 (TBK1) is involved in autophagy and immune signaling. Dominant loss-of-function mutations in TBK1 have been linked to Amyotrophic Lateral Sclerosis (ALS), Fronto-temporal dementia (FTD), and ALS/FTD. However, pathogenic mechanisms remain unclear, particularly the cell-type specific disease contributions of TBK1 mutations.

Analysis of monocyte infiltration in MPTP mice reveals that microglial CX3CR1 protects against neurotoxic over-induction of monocyte-attracting CCL2 by astrocytes.

Background: Evidence from mice suggests that brain infiltrating immune cells contribute to neurodegeneration, and we previously identified a deleterious lymphocyte infiltration in Parkinson's disease mice. However, this remains controversial for monocytes, due to artifact-prone techniques used to distinguish them from microglia. Our aim was to reassess this open question, by taking advantage of the recent recognition that chemokine receptors CCR2 and CX3CR1 can differentiate between inflammatory monocytes and microglia, enabling to test whether CCR2 monocytes infiltrate the brain during dopaminergic (DA) neurodegeneration and whether they contribute to neuronal death.