CXCL8 and primary central nervous system vasculitis: In addition, the CSF sTREM2 level of the PACNS patients was significantly positively correlated with the CSF IL-6 concentration (r=0.753, P=0.031, Figure 3D) and CSF IL-8 concentration (r=0.713, P=0.047, Figure 3E), and negatively correlated with the CSF IL-1β concentration (r=-0.777, P=0.023, Figure 3F).