C57bl 6ncrslc b6 mice

C57BL/6NCrSlc (B6) mice used at Kindai University were purchased from Japan SLC, Inc., Hamamatsu, Japan. All mice were housed and bred in the Experimental Animal Facilities at Kindai University Faculty of Medicine under specific pathogen-free conditions. Mice 7 to 20 weeks in age were used in this study. Mice used in Tsukuba University are described below.

Groups of six-week-old male C57BL/6NCrSlc (B6) mice, each group comprised of 32 mice to form eight group-housing cages, from a mixture of multiple litters were purchased from Japan SLC Inc. (Shizuoka, Japan) and kept in the animal facility of the National Institute of Genetics (NIG) in Japan. Group-housing experiments were performed using polycarbonate cages that were 18 cm wide, 17 cm high and 30 cm deep. The cages were produced for use in behaviour tests of “24 hour home-cage activity and social behaviour monitoring” (Ohara Co. Ltd., Tokyo, Japan). Four animals were kept in each cage, as described below. The animals were supplied with Palsoft paper bedding (Oriental Yeast, Tokyo, Japan). The animal room was maintained at a humidity of 50 ± 10% and a temperature of 23 ± 2 °C under a 12-h light/12-h dark cycle (the light period was from 06:00 to 18:00). The animals were allowed free access to CE-2 food (CLEA Japan, Tokyo, Japan) and water. Mice were maintained and all experiments were performed in accordance with NIG guidelines and all procedures were approved by the NIG Committee for Animal Care and Use (approval no. 26-9).

C57BL/6NCrSlc (B6) mice were purchased from Japan SLC. All the following mice were backcrossed to the B6 or B6-CD45.1 strain: B1-8^flox/+ mice (Lam et al., 1997 (link)), B1-8^hi mice (Shih et al., 2002 (link)), Igk^–/– mice (Chen et al., 1993 (link)), Cd19^cre/+ mice (Rickert et al., 1995 (link)), and Prkcd^–/– mice (Miyamoto et al., 2002 (link)). Prkcd ^fl/fl mice on the B6 background were developed by Drs. Niino, Shioda, and Sakimura (Niino et al., 2021 (link)) and purchased from the RIKEN BioResource Center (RBRC06462). Mice were immunized i.p. with 100 µg of NP₄₆-Ficoll (F-1420; Biosearch Technologies), 1 µg of PPS3 (169 X; American Type Culture Collection) or 100 µg of NP₄₀-CGG in alum (Haniuda et al., 2016 (link)) unless otherwise noted. For flow cytometry of spleen cells, mice were immunized i.v. with 100 µg of NP₄₆-Ficoll. Sex-matched 7–14-week-old mice were used for all experiments. All mice were maintained in the Tokyo University of Science (TUS) mouse facility under specific pathogen-free conditions. Mouse procedures were performed under protocols approved by the TUS Animal Care and Use Committee (Approval No. S19017 and S20011).