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Mast Cells Proliferate in the Peri-Hippocampal Space During Early Development and Modulate Local and Peripheral Immune Cells

ABSTRACT: Brain development is a non-linear process of regionally specific epochs occurring during windows of sensitivity to endogenous and exogenous stimuli. We have discovered an epoch in the neonatal rat brain defined by a transient population of peri-hippocampal mast cells (phMCs) that are abundant from birth through 2-weeks postnatal but absent thereafter. The phMCs are maintained by proliferation and harbor a unique transcriptome compared to mast cells residing in the skin, bone marrow or other brain regions. Pharmacological activation of this population broadly increases blood-brain-barrier permeability, recruits peripheral immune cells and stunts local microglia proliferation. Examination of the post-mortem human brain revealed mast cells in the peri-hippocampal region of a newborn but not an older child, suggesting a similar developmental period exists in humans. Mast cells specifically and early life inflammation generally, have been linked to heightened risk for neurodevelopmental disorders and these results reveal a plausible source of that risk.

ORGANISM(S): Rattus norvegicus

PROVIDER: GSE277694 | GEO | 2024/09/22

REPOSITORIES: GEO

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Mast Cells Proliferate in the Peri-Hippocampal Space During Early Development and Modulate Local and Peripheral Immune Cells

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