Brain-to-cervical lymph node signaling after stroke.
Elga EspositoBum Ju AhnJingfei ShiYoshihiko NakamuraJi Hyun ParkEmiri T MandevilleZhanyang YuSu Jing ChanRakhi DesaiAyumi HayakawaXunming JiEng H LoKazuhide HayakawaPublished in: Nature communications (2019)
After stroke, peripheral immune cells are activated and these systemic responses may amplify brain damage, but how the injured brain sends out signals to trigger systemic inflammation remains unclear. Here we show that a brain-to-cervical lymph node (CLN) pathway is involved. In rats subjected to focal cerebral ischemia, lymphatic endothelial cells proliferate and macrophages are rapidly activated in CLNs within 24 h, in part via VEGF-C/VEGFR3 signalling. Microarray analyses of isolated lymphatic endothelium from CLNs of ischemic mice confirm the activation of transmembrane tyrosine kinase pathways. Blockade of VEGFR3 reduces lymphatic endothelial activation, decreases pro-inflammatory macrophages, and reduces brain infarction. In vitro, VEGF-C/VEGFR3 signalling in lymphatic endothelial cells enhances inflammatory responses in co-cultured macrophages. Lastly, surgical removal of CLNs in mice significantly reduces infarction after focal cerebral ischemia. These findings suggest that modulating the brain-to-CLN pathway may offer therapeutic opportunities to ameliorate systemic inflammation and brain injury after stroke.
Keyphrases
- cerebral ischemia
- brain injury
- lymph node
- subarachnoid hemorrhage
- endothelial cells
- blood brain barrier
- vascular endothelial growth factor
- resting state
- tyrosine kinase
- white matter
- functional connectivity
- neoadjuvant chemotherapy
- squamous cell carcinoma
- nitric oxide
- multiple sclerosis
- high glucose
- epidermal growth factor receptor
- adipose tissue
- radiation therapy
- insulin resistance