The choroid plexus links innate immunity to CSF dysregulation in hydrocephalus

Cell. 2023 Feb 16;186(4):764-785.e21. doi: 10.1016/j.cell.2023.01.017.

Abstract

The choroid plexus (ChP) is the blood-cerebrospinal fluid (CSF) barrier and the primary source of CSF. Acquired hydrocephalus, caused by brain infection or hemorrhage, lacks drug treatments due to obscure pathobiology. Our integrated, multi-omic investigation of post-infectious hydrocephalus (PIH) and post-hemorrhagic hydrocephalus (PHH) models revealed that lipopolysaccharide and blood breakdown products trigger highly similar TLR4-dependent immune responses at the ChP-CSF interface. The resulting CSF "cytokine storm", elicited from peripherally derived and border-associated ChP macrophages, causes increased CSF production from ChP epithelial cells via phospho-activation of the TNF-receptor-associated kinase SPAK, which serves as a regulatory scaffold of a multi-ion transporter protein complex. Genetic or pharmacological immunomodulation prevents PIH and PHH by antagonizing SPAK-dependent CSF hypersecretion. These results reveal the ChP as a dynamic, cellularly heterogeneous tissue with highly regulated immune-secretory capacity, expand our understanding of ChP immune-epithelial cell cross talk, and reframe PIH and PHH as related neuroimmune disorders vulnerable to small molecule pharmacotherapy.

Keywords: CSF; NKCC1; SPAK; blood-CSF barrier; cerebrospinal fluid; choroid plexus; hydrocephalus; neuro-inflammation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood-Brain Barrier / metabolism
  • Brain / metabolism
  • Choroid Plexus* / metabolism
  • Cytokine Release Syndrome / pathology
  • Humans
  • Hydrocephalus* / cerebrospinal fluid
  • Hydrocephalus* / immunology
  • Immunity, Innate