Sodium acetate

Cholesterol (Nippon Fine Chemical Co., Ltd, Japan), Dlin-MC3-DMA (AVT Pharmaceutical Tech Co. Ltd., China), DSPC (Nippon Fine Chemical Co., Ltd), DMG-PEG2000 (AVT Pharmaceutical Tech Co. Ltd., China), Ethyl alcohol (Tedia, USA), sodium acetate (FUJIFILM Wako Pure Chemical Corporation, Japan), acetic acid (Sigma Aldrich, Germany), water for injection (WFI), HEPES (FUJIFILM Wako Pure Chemical Corporation, Japan), sodium acetate (FUJIFILM Wako Pure Chemical Corporation, Japan), sodium hydroxide (Merck Germany), disodium hydrogen phosphate (FUJIFILM Wako Pure Chemical Corporation, Japan), potassium dihydrogen phosphate (FUJIFILM Wako Pure Chemical Corporation, Japan), sodium chloride (Merck, Germany), potassium chloride (FUJIFILM Wako Pure Chemical Corporation, Japan) were used in relevant experiments. Water for injection (WFI) was used for water.
Seven Excellence pH/ion meter (Mettler Toledo, Switzerland), Excellence Plus High-Performance Microbalance (Mettler Toledo, Switzerland) and Precision balance (Mettler Toledo, Switzerland), General T-mixture (In-house developed), SB—4200DTS sonication system (Ningbo science Biotechnology Co., Ltd., China) were used. The AKTA flux S and AKTA flux 6 TFF system (GE Healthcare, Sweden) and 0.1 m² NMWCO 100 kDa PES cassette (Sartorius Stedim, Germany) were used in buffer exchange step for 100 × scale-up batch.

Sodium acetate (0.1 M; Fujifilm Wako Pure Chemical Corp.) and 0.1 M acetate (Fujifilm Wako Pure Chemical Corp.) were mixed to prepare TRAP buffer. Naphthol AS-Mix phosphate (Sigma-Aldrich Co., LLC., MO, USA) diluted with N,N-Dimethylformamide (Fujifilm Wako Pure Chemical Corp.) and fast red violet LB salt (Sigma-Aldrich Co., LLC.) were diluted with TRAP buffer to prepare TRAP staining solution. Cells were fixed by 10% formaldehyde (Fujifilm Wako Pure Chemical Corp.) for 30 min. Fixed cells were stained by adding TRAP staining solution for 20 min.

Mice were fed either normal chow containing 5% cellulose (Clea diet AIN-93G) or a low-fiber diet (Clea diet AIN-93G without cellulose). When studying the effect of a high-fiber diet, mice were given a low-fiber diet supplemented with 30% pectin (Wako, Tokyo, Japan). All diets were purchased from CLEA Laboratory Animal Corp. Mice were adapted to low-fiber or high-fiber chow 2 weeks before immunization and throughout the study.
When studying the effect of SCFAs, mice were given sodium acetate or sodium propionate or sodium butyrate (Wako) in the drinking water at a final concentration of 200 mM for 3 weeks before immunization and throughout the study. Mice were given normal drinking water in the control group.