C57bl 6 b6 mice

C57BL/6 (B6) mice (Janvier; Le Genets-St-Isle; France), B6-Foxp3^eGFP mice (B6.Cg-Foxp3^tm2(EGFP)Tch/J; Jackson # 006772), PD-1^−/− mice36 (link) and PD-L1^−/− (B7-H1^−/−) mice35 (link) and were bred and kept under standard pathogen-free conditions in the animal colony of Ulm University (Ulm, Germany). All mouse immunization studies were carried out in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the German Federal Animal Protection Law. The protocols were approved by the Committee on the Ethics of Animal Experiments of the University of Ulm (Tierforschungszentrum Ulm, Oberberghof) and the Regierungspräsidium Tübingen (Permit Numbers: 1105 and 1199 to RS). All studies were carried out in accordance with the approved guidelines. Immunizations were performed under short time Isofluran anesthesia, and all efforts were made to minimize suffering. Development of autoimmune diabetes was analysed by regular blood glucose measurements and diagnosed if two consecutive blood glucose values (within 2 days) exceeded 250 mg/dl, i.e. 13.8 mmol/l (Disetronic Freestyle, Sulzbach, Germany).

C57BL/6 (B6) mice were purchased from Janvier Labs. Congenic Ly5.1^{61 (link)} and Thy1.1⁶² , Foxp3-GFP.KI^{63 (link)} and Thy1.1-IL-10 reporter mice^{30 (link)}, P14^{64 (link)}, Smarta^{65 (link)}, IL-10^{[−/−66 (link)}, and PKOB mice have been described previously and were all on C57BL/6 background. Mice were used between 8 and 16 weeks of age and were sex and age matched within experiments. All animals were bred and housed in SPF and OHB facilities at LASC Zürich, Switzerland. All experiments were performed in accordance with institutional ethical policies and national regulations and have been reviewed and approved by the Cantonal veterinary office of Zurich.

C57BL/6 (B6) mice were purchased from Janvier Laboratories and Foxp3-GFP.KI reporter^{33 (link)} and SMARTA^{34 (link)} mice have been described previously. All mice were housed and bred in SPF or OHB facilities at LASC Zurich, Switzerland. All experiments were reviewed and approved by the cantonal veterinary office of Zurich and were performed in accordance with Swiss legislation.
Lymphocytic choriomeningitis virus (LCMV) WE was propagated on L929 fibroblast cells, Vaccinia Virus (VV) on BSC40 cells. Sex- and age-matched mice, 6–12 weeks of age were infected i.v. with 200 ffu LCMV, or i.p. with 2 × 10⁶ ffu VV. For footpad infections 50 μL of PBS containing 500 ffu of LCMV were injected s.c. into the right hind footpad^{23 (link)}. Epicutaneous ear infections were modified from a previous report^{24 (link)} and performed by piercing the ear five times with a bifurcated needle that was dipped into VV stock (7.65 × 10⁸ ffu/mL) in between punches. The contralateral footpads or ears served as a control and were mock infected in an identical manner using sterile PBS. Swelling of the infected site was monitored daily with a spring-loaded caliper.