• IFNAR1 (interferon alpha and beta receptor subunit 1), together with IFNAR2, forms the heterodimeric receptor for type I interferons. After binding with type I interferons, the IFNAR1/IFNAR2 receptor activates the JAK-STAT signaling cascade, which result in the transcriptional activation or repression of interferon-regulated genes.
• IFNGR1 (interferon gamma receptor 1) encodes the ligand-binding chain (alpha) of the gamma interferon receptor. Human interferon-gamma receptor is a heterodimer of IFNGR1 and IFNGR2. The importance of IFNG in the immune systems in part from its ability to inhibit viral replication directly, and most importantly from its immunostimulatory and immunomodulatory effects.
• The genome sequences between exons 1-11 in mouse Ifnar1 gene and were depleted in B-Ifnar1_Ifngr1 DKO mice(129S2). The genome sequences between exons 1-5 in mouse Ifngr1 gene were depleted in B-Ifnar1_Ifngr1 DKO mice(129S2). 
• Mouse IFNAR1 and IFNGR1 was only detectable in T cells, B cells, dendritic cells, macrophages, monocytes, and neutrophils of wild-type C57BL/6JNifdc mice and 129S2/SvPasCrl mice, but not in B-Ifnar1/Ifngr1 DKO mice(129S2).
• Mouse Ifnar1 and mouse Ifnar1 mRNA was only detectable in wild-type mice 129S2/SvPasCrl  and C57BL/6J , but not in  B-Ifnar1_Ifngr1 DKO mice(129S2).
• This model is useful in studying the role of IFN pathways in anti-viral and anti-microbial infections.

Gene targeting strategy for B-Ifnar1_Ifngr1 KO mice(129S2). The genome sequences between exons 1-11 in mouse Ifnar1 gene and were depleted in B-Ifnar1_Ifngr1 DKO mice(129S2). The genome sequences between exons 1-5 in mouse Ifngr1 gene were depleted in B-Ifnar1_Ifngr1 DKO mice(129S2).  As a result, mouse Ifnar1 and Ifngr1 protein will not be expressed anymore in B-Ifnar1_Ifngr1 KO mice(129S2).  

Strain specific IFNAR1 expression analysis in wild-type C57BL/6JNifdc mice, 129S2/SvPasCrl mice and homozygous  B-Ifnar1/Ifngr1 DKO mice(129S2) by flow cytometry. Splenocytes were collected from wild-type C57BL/6JNifdc mice, 129S2/SvPasCrl mice and homozygous B-Ifnar1/Ifngr1 DKO mice(129S2). Protein expression was analyzed with anti-mouse IFNAR1 antibody (Biolegend, 127311) by flow cytometry. Mouse IFNAR1 was only detectable in wild-type C57BL/6JNifdc mice and 129S2/SvPasCrl mice, but not in homozygous B-Ifnar1/Ifngr1 DKO mice(129S2).

Strain specific IFNGR1 expression analysis in wild-type C57BL/6JNifdc mice, 129S2/SvPasCrl mice and homozygous  B-Ifnar1/Ifngr1 DKO mice(129S2) by flow cytometry. Splenocytes were collected from wild-type C57BL/6JNifdc mice, 129S2/SvPasCrl mice and homozygous B-Ifnar1/Ifngr1 DKO mice(129S2). Protein expression was analyzed with anti-mouse IFNGR1 antibody (Invitrogen, 12-1191-80) by flow cytometry. Mouse IFNGR1 was only detectable in wild-type C57BL/6JNifdc mice and 129S2/SvPasCrl mice, but not in homozygous B-Ifnar1/Ifngr1 DKO mice(129S2).

Strain specific analysis of mIfnar1 and mIfngr1 mRNA expression in wild-type 129S2/SvPasCrl, C57BL/6JNifdc mice, and B-Ifnar1_Ifngr1 DKO mice(129S2) by RT-PCR. Spleen RNA were isolated from wild-type 129S2/SvPasCrl (+/+), C57BL/6JNifdc mice (+/+), and homozygous B-Ifnar1_Ifngr1 DKO mice(129S2) (-/-), then cDNA libraries were synthesized by reverse transcription, followed by PCR with mouse Ifnar1 and mouse Ifngr1  primers. Mouse Ifnar1 and Mouse Ifnar1 mRNA was only detectable in wild-type mice 129S2/SvPasCrl  and C57BL/6JNifdc , but not in  B-Ifnar1_Ifngr1 DKO mice(129S2).