The precipitate was collected after centrifugation at 10,000 g for 20 min.
The precipitate was dissolved in 0.5 mol/L acetic acid at the ratio of
1:9 (w/v) and then dialyzed in 20 volumes of 0.1 mol/L acetic acid,
followed by distilled water. All processes were carried out at 4 C. ASC was lyophilized and then stored at 20 C until experimentation.