New immune regulators of sciatic nerve regeneration?Lessons from the neighborhood

For decades,the immune system has been associated with host protection against infectious pathogens or tumors,while also contributing to autoimmunity.Notwithstanding,this paradigm is now changing,with recent studies highlighting novel roles for immune mediators in the maintenance of steady-state tissue homeostasis.In this perspective,we review some of the latest findings featuring immune modulators of the nervous system pathophysiology,with a special focus on interleukin(IL)-17.

The neurosphere assay:an effective in vitro technique to study neural stem cells

Neural stem cells(NSCs)are known to be present in the adult mammalian brain where they constitutively differentiate into the neuronal,astroglial,and oligodendroglial lineages,in defined processes termed neurogenesis,ast rogl iogenesis and oligodendrogenesis,respectively(reviewed in Braun and Jessberger,2014).During brain development,NSCs are present throughout the brain,becoming progressively restricted to defined brain regions.In the adult brain,NSCs are mainly present in areas classically known as neurogenic niches,i.e.the subventricular zone(SVZ),along the lateral walls of the lateral ventricles,and the subgranular zone,located in the dentate gyrus(DG)of the hippocampus.

A 96-wells fluidic system for high-throughput screenings under laminar high wall shear stress conditions

The ability of endothelial cells to respond to blood flow is fundamental for the correct formation and maintenance of a functional and hierarchically organized vascular network.Defective flow responses,in particular related to high flow conditions,have been associated with atherosclerosis,stroke,arteriovenous malformations,and neurodegenerative diseases.Yet,the molecular mechanisms involved in high flow response are still poorly understood.Here,we described the development and validation of a 96-wells fluidic system,with interchangeable cell culture and fluidics,to perform high-throughput screenings under laminar high-flow conditions.We demonstrated that endothelial cells in our newly developed 96-wells fluidic system respond to fluid flow-induced shear stress by aligning along the flow direction and increasing the levels of KLF2 and KLF4.We further demonstrate that our 96-wells fluidic system allows for efficient gene knock-down compatible with automated liquid handling for high-throughput screening platforms.Overall,we propose that this modular 96-well fluidic system is an excellent platform to perform genome-wide and/or drug screenings to identify the molecular mechanisms involved in the responses of endothelial cells to high wall shear stress.

Mannosylated glycans impair normal T-cell development by reprogramming commitment and repertoire diversity

T-cell development ensures the formation of diverse repertoires of T-cell receptors(TCRs)that recognize a variety of antigens.Glycosylation is a major posttranslational modification present in virtually all cells,including T-lymphocytes,that regulates activity/functions.Although these structures are known to be involved in TCR-selection in DP thymocytes,it is unclear how glycans regulate other thymic development processes and how they influence susceptibility to disease.Here,we discovered stage-specific glycome compositions during T-cell development in human and murine thymocytes,as well as dynamic alterations.After restricting the N-glycosylation profile of thymocytes to high-mannose structures,using specific glycoengineered mice(Rag1CreMgat1fl/fl),we showed remarkable defects in key developmental checkpoints,includingß-selection,regulatory T-cell generation andγδT-cell development,associated with increased susceptibility to colon and kidney inflammation and infection.We further demonstrated that a single N-glycan antenna(modeled in Rag1CreMgat2fl/fl mice)is the sine-qua-non condition to ensure normal development.In conclusion,we revealed that mannosylated thymocytes lead to a dysregulation in T-cell development that is associated with inflammation susceptibility.

基于单细胞多组学研究揭示小鼠γδT细胞的新发现

γδT cells are a second T cell lineage conserved throughout evolution and across animal species that express aγδT-cell receptor(TCR)consisting of a TCRγand a TCRδchain.γδT cells develop in the murine thymus into various subsets with distinct functional potential that preferentially home to specific peripheral tissues,rather than lymphoid organs[1].