Quantification of IL-1β and RvD1 in Serum and CSF

IL-1β ELISA kits were from BioLegend (Catalog number, 432604) and the assay was conducted according to the manufacturer’s protocol. RvD1 ELISA kits from Cayman Chemicals (Catalog number, 500380) were used. For each reaction, 50 μl of serum (collected from tail vein) and 20 μl of CSF (collected from cisterna magna) were collected. Each ELISA was conducted according to the manufacturer’s instruction, and standard curves were included each time. RvD1 ELISA was conducted as previously described (Zhang et al., 2018 (link); Tao et al., 2020 (link)) and measured by comparing binding to that of a tracer consisting of RvD1 linked to acetylcholinesterase (AChE) per the manufacturer’s protocol (Cayman Chemicals). The samples and the competition RvD1 tracer were incubated overnight at 4°C. The signal in ELISA plate was developed by Ellman’s Reagent, a substrate of AChE. The optical densities of samples were measured using an ELISA plate reader (Bio-Rad) at a wavelength of 420 nm and RvD1 levels were calculated using the standard curves.