Enzyme-Linked Immunosorbent Assay (ELISA)
Cell supernatants were centrifuged at 450×g for 5 mins and stored at
-20°C until usage. Cytokine concentrations were determined using ELISA
Duoset kits for mouse IL-1β, IL-6 and TNF-α according to the
manufacturer’s protocol (#DY401, #DY406 and #DY410, respectively;
R&D System, Minneapolis, Canada). Absorbance at the wavelength of
450 nm was measured using a plate reader (SpectraMax 190; Molecular
Devices, San Jose, California, USA) as a correction wavelength of
540 nm. Concentrations were calculated using eight-parameter fit curve.