Mice homozygous for Fcgr2tm1Ttk have elevated Immunoglobulin levels in response to thymus-dependent and thymus-independent antigens. Mice are sensitive to IgG-triggered degranulation and have an enhanced passive cutaneous analphylaxis reaction. These mice may be useful for studies of allergic and autoimmune disorders, including systemic lupus erythematosus (SLE).
Dr. Jeffrey V. Ravetch, Memorial Sloan Kettering Cancer Center
Mice homozygous for the Fcgr2tm1Ttk targeted mutation are viable and fertile. Myeloid and lymphoid development is normal. Immunoglobulin levels are elevated in response to thymus-dependent and thymus-independent antigens. Mice are sensitive to IgG-triggered degranulation and have an enhanced passive cutaneous analphylaxis reaction.
A targeting vector was designed to replace exon "S2" of the targeted gene with a neomycin resistance cassette. The construct was electroporated into 129S4/SvJae-derived J1 embryonic stem (ES) cells. Homozygous mutant mice on a mixed C57BL/6;129 genetic background were sent to The Jackson Laboratory in 1997. After arrival, mutant mice were bred with B6129SF1/J (Stock No. 101043) and/or B6129SF2/J (Stock No. 101045) for at least one generation to maintain/cryopreserve/rederive the living colony.
|Allele Name||targeted mutation 1, Toshiyuki Takai|
|Allele Type||Targeted (Null/Knockout)|
|Allele Synonym(s)||FcgammaRII; FcgammaRII-; FcgammaRII2B-; FcgammaRIIB-; Fcgr2btm1Rav; FcgRIIB129-; FcRIIB-; IIB-; TAC264|
|Gene Symbol and Name||Fcgr2b, Fc receptor, IgG, low affinity IIb|
|Strain of Origin||129S4/SvJae|
|Molecular Note||A 2.3 kb genomic fragment containing the S1 and EC1 exons was replaced by a neomycin resistance cassette. Encoded transcript was undetectable in homozygous mutant mice via Northern blot analysis (data not shown). Western blot analysis of LPS-stimulated B cells derived from homozygous mice confirmed that no protein was made from this allele, and FACS analysis demonstrated that no functional protein was expressed on the cell surface of B cells in homozygous mice.|
|Mutations Made By|| |
Dr. Jeffrey Ravetch, Memorial Sloan Kettering Cancer Center
The expected coat color from breeding is Agouti and Black.
When using the FcgγRIIb - mouse strain in a publication, please cite the originating article(s) and include JAX stock #002848 in your Materials and Methods section.