Chinese scholars have made progress in the study of meningeal immunity in adult mice

Figure Stem cells were found to exert meningeal immunity in the steady-state meninges of adult mice

With the funding of the National Natural Science Foundation of China (approval numbers: 81930027, 92169207, 81625010), Zhang Jiyan's team at the Beijing Brain Science and Brain-like Research Center found that adult mouse steady-state meninges have hematopoietic stem cells, and the research results were based on "Identification of hematopoietic stem residing cells in the adult mouse steady-state meninges.
" Meninges of Adult Mice at Steady State", published online in the journal
Cell Reports on November 8, 2022.
Link to the paper: https://doi.
org/10.
1016/j.
celrep.
2022.
111592
.

Traditional theories suggest that the blood-brain barrier acts as a solid protective layer to provide an immune-immune environment
for the central nervous system.
Hematopoietic stem cells are present in mammalian fetal liver, umbilical cord blood and bone marrow, and have the potential
for self-renewal and multidirectional differentiation.
It has been reported that there are settled hematopoietic precursor cells in tissues and organs such as liver and lungs, which can differentiate in situ to produce specific tissue-resident immune cells, but multi-lineage steady-state extramedullary hematopoiesis in adulthood has not been found
.

Through single-cell transcriptome sequencing analysis and flow cytometry sorting, the presence of hematopoietic stem cells
in the meningeal homeostasis environment of adult mice was found.
These hematopoietic stem cells colonize mice after birth, present a specific transcriptional profile, have the potential for self-renewal and multidirectional differentiation, and can provide the central nervous system with white blood cells more adapted to the local microenvironment (Figure).

The results revealed the existence of a "self-sufficient" pool of immune cells in the meninges, which expanded our understanding of physiological extramedullary hematopoiesis and provided a new theoretical reference
for meningeal immunity.