Ifn γ

The HLA- DQ8/DRB1*0301 double transgenic (Tg) mice [DQ8 (DQA1*0103, DQB1*0302).-DRB1*0301 (DRB1*0301] were produced as previously described (11 (link), 19 (link)). Briefly, HLA class II transgenes were introduced into (B6 × SWR)F₁ fertilized eggs. Positive offspring were backcrossed to B10.M mice for several generations. HLA class Tg mice were mated with MHC class II deficient mice (AE^−/−) on B6 background (7 (link)) and intercrossed to generate the HLA-DRB1*0301.AE^−/− and HLA-DQ8.AE ^−/− Tg lines. HLA-DRB1*0301.AE^−/− and HLA-DQ8.AE ^−/− Tg mice were separately mated with IFNγ-deficient mice on B6 background (Jackson Laboratory) to generate HLA-DRB1*0301.AE^−/−.IFNγ^−/−, and HLA-DQ8.AE^−/−.IFNγ^−/− respectively. DRB1*0301.DQ8.AE^−/−.IFNγ^−/− Tg mice were produced by intercrossing HLA-DRB1*0301.AE^−/−.IFNγ^−/− with HLA-DQ8.AE^−/−.IFNγ^−/− mice. Majority of HLA class-II Tg mice have mixed B6/B10 background. All mice were bred and maintained in the pathogen-free Immunogenetics Mouse Colony of Mayo Clinic according to National Institutes of Health and institutional guidelines. All experiments were approved by the Institutional Animal Care and Use Committee (IACUC) at Mayo Clinic, Rochester.

Female BALB/c, RAG1^−/−, IFN-γ^−/−, SCID, and (C57BL/6 × SJL)F1 hybrid mice were from the Jackson Laboratories and Swiss-Webster mice were from Taconic. RAG1^−/−IFN-γ^−/− mice were generated by mating RAG1^−/− with IFN-γ^−/− animals. For generation of a transgenic mouse strain that produces IFN-γ only in CD11b-expressing cells, the pCD11b-IFN-γ transgene (Fig. 2B) was constructed by placing IFN-γ coding sequence under control of the CD11b promoter by modifying a CD11b-Thy1.1 construct (5 (link)) kindly provided by Dr. Daniel Tenen of Harvard Medical School. After confirming the activity of pCD11b-IFN-γ to induce production of IFN-γ only in CD11b⁺ cells by transfecting CD11b⁺ (J774) and CD11b⁻ (COS7) cells in vitro (Supplemental Table I), pCD11b-IFN-γ transgene was microinjected into zygotes from (C57BL/6 × SJL)F1 hybrid animals. Pups carrying the transgene identified by PCR (Fig. 2C) were mated to (C57BL/6 × SJL)F1, backcrossed to BALB/c mice 6 times, and then mated with IFN-γ^−/− mice to generate animals that express this cytokine only by CD11b⁺ cells (CD11b only-IFN-γ mice). Experimental procedures were performed in accordance with approved protocols from the Institutional Animal Care and Use Committee.

C57BL/6j (B6; H2K^b), BALB/c (H2K^d), IFN-γ−/−, Prf1−/−, and Rag2IL2Rg doubly deficient mice were purchased from The Jackson Laboratory (Bar Harbor, ME). MyD88KO mice on a C57BL/6 background were a generous gift from R. Medzhitov (HHMI, Yale University, New Haven, CT, USA). IL-36R −/− mice (C57BL/6-Il1rl2 (Derer et al., 2014 (link))) were provided by Amgen (Seattle, WA) via Taconic (Hudson, NY) under an approved MTA. All mice were housed in the specific pathogen-free facility of the University of Pittsburgh School of Medicine or Soochow University. Experiments were conducted under an institutional animal care and use committee-approved protocol and in accordance with National Institutes of Health guidelines.