B6.129S4(Cg)-Igk^{tm1(Igk564)Tik} Igh^{tm1(Igh564)Tik}/J

Stock number: 032723
Product name: 564Igi
Research areas: Immunology, Inflammation and Autoimmunity Research, Internal/Organ Research

Description

564Igi is a model of systemic lupus erythematosus (SLE) that incorporates heavy and light chain genes encoding 564 immunoglobulin (derived from an autoimmune SWRxNZB hybridoma) targeted to the heavy and light chain loci of C57BL/6 mice. Autoantibodies produced by compound homozygotes are sufficient to cause kidney pathology consistent with those seen in glomerulonephropathies in human patients.

Detailed description

Systemic lupus erythematosus (SLE) is characterized by the production of autoantibodies that are frequently directed against nucleic acid-associated antigens. This 564Igi model system incorporates heavy and light chain genes encoding 564 immunoglobulin (derived from an autoimmune SWRxNZB hybridoma) targeted to the heavy and light chain loci in non-autoimmune C57BL/6 background mice.

The antibody recognizes RNA, single-stranded DNA, and nucleosomes. B cells expressing this immunoglobulin are activated, producing class-switched autoantibody in vivo despite an apparently normal induction of anergy. Production of these autoantibodies is sufficient to cause kidney pathology, as determined by immunofluorescent staining, and electron/light microscopy of frozen kidney sections taken from 13-month-old animals.

Compound heterozygous (HET/HET) breedings are recommended for this strain. Compound homozygous (HOM/HOM) females are not good mothers as the antibodies they produce react to molecules in the brain of pups, resulting in death during development. They also become very sick around 1 year of age.  HOM/HOM males survive better (sometimes up to 2 years), but develop cognitive disorders.

Development

To create the 564Igi light chain mutation, the entire Jκ region of mouse Igk gene was replaced with a loxP-flanked neomycin cassette and a rearranged VκJκ5 light chain segment amplified from hybridoma 564 (derived from autoimmune SWRxNZB mice) via homologous recombination in 129S4/SvJae-derived J1 embryonic stem (ES) cells. The integrated segment begins 686 bp upstream of the 564 Vκ gene (incorporating all the regulatory sequences) and ends 498 bp downstream of Jκ5. Resultant male chimeric mice were crossed with mice expressing CMV-cre to excise the neomycin cassette, then backcrossed to C57BL/6J for at least 10 generations.

To create the 564Igi heavy chain mutation, a segment of DNA including DQ52 and the entire JH region of the mouse Igh gene was replaced with a loxP-flanked neomycin cassette and rearranged VDJ heavy chain segment from hybridoma 564 (derived from autoimmune SWRxNZB mice) via homologous recombination. Resultant male chimeric mice were crossed with mice expressing cre recombinase to excise the neomycin cassette, but the presence of neomycin segregating with the Igh mutation has been detected in the colony at The Jackson Laboratory. This allele was backcrossed to C57BL/6J for at least 10 generations by the donating laboratory.

Mice carrying the heavy and light chain mutations were intercrossed to generate mice with targeted insertions at both loci by the donating laboratory.

Allele

Symbol: Igk^{tm1(Igk564)Tik}
Name: targeted mutation 1, Thereza Imanishi-Kari
MGI accession ID: MGI:3687307
Generation method: Targeted
Attributes: Inserted expressed sequence
Marker symbol: Igk
Marker name: immunoglobulin kappa chain complex
Marker synonyms: kappa
Chromosome: 6
Strain of origin: 129S4/SvJae
Molecular note: A floxed neomycin resistance gene, as well as the 564 VkappaJkappa5 region from a hybridoma derived from an autoimmune SWRxNZB mouse, replaced a segment of DNA including the entire J kappa region. Male chimeric mice were bred to C57BL/6 females. Offspring from these mice were crossed with cre expressing transgenic mice in order to excise the neomycin resistance cassette.

Allele

Symbol: Igh^{tm1(Igh564)Tik}
Name: targeted mutation 1, Thereza Imanishi-Kari
MGI accession ID: MGI:6287435
Generation method: Targeted
Attributes: Inserted expressed sequence
Synonyms: IgH564
Marker symbol: Igh
Marker name: immunoglobulin heavy chain complex
Chromosome: 12
Strain of origin: 129S4/SvJae
Molecular note: A floxed neomycin resistance gene, as well as the VDJ 564 region from a hybridoma derived from an autoimmune SWRxNZB mouse, replaced a segment of DNA including DQ52 and the entire JH region.
General note: The version of this allele that does not contain the neomycin selection cassette, Igh^{tm1.1(Igh564)Tik}, has been analyzed.