Role of human dural fibroblasts in the angiogenic responses of human endothelial cells: An in vitro dural model and the application of lab‐on‐a‐chip for EDAS

Encephaloduroarteriosynangiosis (EDAS), an indirect anastomosis procedure, is widely accepted as a primary treatment for moyamoya disease (MMD) to improve collateral blood flow. During surgical intervention, dural fibroblasts (DuF) are thought to produce various proteins that create an angiogenic microenvironment. However, the biophysiological evidence supporting the angiogenic properties of this surgical technique has not been thoroughly elucidated. The purpose of these studies was to determine whether DuF releases pro‐angiogenic factors and chemokines and promotes angiogenic properties in human endothelial cells (ECs) under IL‐1β‐mediated wound conditions, which are expected to occur during the process of neo‐vascularization within the dura mater. Furthermore, a microfluidic chemotaxis platform was implemented to investigate the angiogenic activity of ECs in response to a reconstituted dura model. Transcriptome sequencing revealed that IL‐1β stimulation on DuF induced a significant upregulation of various pro‐angiogenic genes, including IL‐6, IL‐8, CCL‐2, CCL‐5, SMOC‐1, and SCG‐2 (p < 0.05). Moreover, compared to ECs cultured in naïve media or naïve DuF media, those exposed to IL‐1β‐DuF conditioned media expressed higher mRNA and protein levels of these pro‐angiogenic factors (p < 0.001). ECs co‐cultured with IL‐1β‐DuF also exhibited considerable migration on the microfluidic chemotaxis platform. Furthermore, the chemotactic effects on the ECs were reduced upon neutralization of IL‐8 or inhibition of NF‐κB signaling. Our findings demonstrate that IL‐1β‐DuFs release factors that activate and enhance the angiogenic properties of ECs. These results suggest a potential interaction between DuF and ECs following EDAS for MMD, and these components could be targeted for the development of therapeutic biomarkers.