A novel perivascular cell population in the zebrafish brain
Abstract
The blood-brain barrier is essential for the proper homeostasis and function of the CNS, but its mechanism of function is poorly understood. Perivascular cells surrounding brain blood vessels are thought to be important for blood-brain barrier establishment, but their roles are not well defined. Here, we describe a novel perivascular cell population closely associated with blood vessels on the zebrafish brain. Based on similarities in their morphology, location, and scavenger behavior, these cells appear to be the zebrafish equivalent of cells variably characterized as Fluorescent Granular Perithelial cells (FGPs), perivascular macrophages, or 'Mato Cells' in mammals. Despite their macrophage-like morphology and perivascular location, zebrafish FGPs appear molecularly most similar to lymphatic endothelium, and our imaging studies suggest that these cells emerge by transdifferentiation from endothelium of the optic choroidal vascular plexus. Our findings provide the first report of a perivascular cell population in the brain derived from vascular endothelium.
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Author details
Funding
Eunice Kennedy Shriver National Institute of Child Health and Human Development (Z1A HD008808)
- Marina Venero Galanternik
- Daniel Castranova
- Aniket V Gore
- Hyun Min Jung
- Amber N Stratman
- Mayumi F Miller
- Brant M Weinstein
National Human Genome Research Institute
- Martha R Kirby
Japan Agency for Medical Research and Development
- Koichi Kawakami
Japan Society for the Promotion of Science (JP15H02370 / JP16H01651)
- Koichi Kawakami
Eunice Kennedy Shriver National Institute of Child Health and Human Development (Z1A HD000412-30)
- Nathan H Blewett
- James Iben
- Richard J Maraia
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (ASP # 12-039 and 15-017).
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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