B6NCrl.129(B6)-Apoe^tm1Unc Ccr1^tm1Gao Ccr5^tm1Blck/BlckJ

Stock number: 030895
Product name: 15AE-B
Research areas: Cardiovascular Research, Mouse/Human Gene Homologs, Research Tools

Description

15AE-B mice are C57BL/6NCrl-congenic triple mutant animals harboring the ApoE knock-out allele (Apoe^tm1Unc), the CCR1 knock-out allele (Ccr1^tm1Gao) and the CCR5 knock-out allele (Ccr5^tm1Blck). These mice are useful for studying the pathogenesis and treatment of atherosclerosis, as well as lipoprotein/cholesterol metabolism, neurovascular function, inflammation and neurodegenerative cardiovascular disease.

Detailed description

C57BL/6N-congenic 15AE-B mice homozygous for knock-out alleles of ApoE, Ccr1 and Ccr5 (ApoE-/-Ccr1-/-Ccr5-/-) are viable and fertile with no apparent reproductive abnormalities.

Dr. Bruno Luckow has made the following C57BL/6N-congenic strains available: ApoE knock-out (AE-B; Stock No. 030891), ApoE Ccr1 double knock-out (1AE-B; Stock No. 030892), ApoE Ccr2 double knock-out (2AE-Bd; Stock No. 030893), ApoE Ccr5 double knock-out (5AE-B; Stock No. 030894), ApoE Ccr1 Ccr5 triple knock-out (15AE-B; Stock No. 030895) and ApoE Ccr2 Ccr5 triple knock-out (25AE-Bd; Stock No. 030896).

Development

These 15AE-B mice (Stock No. 030895) are C57BL/6NCrl-congenic triple mutant animals harboring the ApoE knock-out allele (Apoe^tm1Unc), the CCR1 knock-out allele (Ccr1^tm1Gao) and the CCR5 knock-out allele (Ccr5^tm1Blck). Each mutant allele is described below.

The ApoE knock-out allele (Apoe^tm1Unc) was created in the laboratory of Dr. Nobuyo Maeda (University of North Carolina at Chapel Hill) to have a neo cassette replacing part of the coding region of the apolipoprotein E Locus on chromosome 7. In 2005, Dr. Bruno Luckow (Klinikum der Universitaet Muenchen) obtained C57BL/6J-congenic ApoE knock-out mice from The Jackson Laboratory (Stock No. 002052), bred them several generations to C57BL/6NCrl mice (Charles River Laboratories), and then used them as described below.

The CCR1 knock-out allele (Ccr1^tm1Gao) was created by Dr. Ji-Liang Gao in the laboratory of Dr. Philip M. Murphy (National Institutes of Health [NIH]). The targeting vector was designed to replace part of the coding region of the chemokine (C-C motif) receptor 1 locus on chromosome 9 with a neo cassette. After electroporation into 129S4/SvJae-derived J1 embryonic stem (ES) cells, chimeras were bred to C57BL/6 mice to establish their CCR1 knock-out colony. They were backcrossed six generations with C57BL/6J mice, and then sent to Dr. Luckow in 1999. The CCR1 knock-out colony was then backcrossed ten generations to C57BL/6NCrl, and subsequently used as described below.

The CCR5 knock-out allele (Ccr5^tm1Blck) was created in the laboratory of Dr. Bruno Luckow (Klinikum der Universitaet Muenchen) to have a lacZ::neo cassette replacing most of the ORF on exon 2 (thereby deleting 342 of 354 amino acids) of the chemokine (C-C motif) receptor 5 locus on chromosome 9. After electroporation into 129P2/OlaHsd-derived E14.1 embryonic stem (ES) cells, chimeras were bred to C57BL/6NCrl mice to establish their CCR5 knock-out colony. The CCR5 knock-out colony was backcrossed ten generations to C57BL/6NCrl, and then used as described below.

To generate the ApoE/CCR1/CCR5 triple mutant colony [15AE-B], Dr. Luckow bred some CCR5 knock-out mice to CCR1 knock-out mice, and the resulting CCR1/CCR5 double mutants were backcrossed to C57BL/6NCrl mice [Charles River Laboratories] for ten generations. Next, the double mutant mice were bred to C57BL/6J-congenic ApoE knock-out mice. The donating investigator reports that the ApoE/CCR1/CCR5 triple mutant colony [15AE-B] was backcrossed to C57BL/6NCrl for a total of at least six generations prior to sending mice to The Jackson Laboratory in 2017 as Stock No. 030895. Upon arrival, sperm was cryopreserved.
Of note, the donating investigator reports that it is likely that the Y chromosome of the congenic strain is of C57BL/6NCrl origin.

Also of note, the Ccr1 and Ccr5 loci are ~153 kbp apart on chromosome 9 [GRCm38.p5].

In 2017, a SNP (single nucleotide polymorphism) panel analysis, with 43 markers covering all 19 chromosomes and the X chromosome, as well as 5 markers that distinguish between the C57BL/6N and C57BL/6J substrains, was performed on the male mice sent to The Jackson Laboratory Repository. All markers were C57BL/6 allele-type. In addition, 2 of 5 markers that determine C57BL/6 substrains were found to be non-homozygous for C57BL/6N allele-type (C57BL/6J homozygous for chromosome 6 marker [~107.8 Mbp] and C57BL/6N;C57BL/6J heterozygous for chromosome 19 marker [~49.9 Mbp]). It is likely that the C57BL/6NCrl allele-type at the chromosome 6 marker is the same as C57BL/6J allele-type (rather than C57BL/6NJ allele-type). The chromosome 19 marker is This suggests that the mice sent to The Jackson Laboratory retained a some C57BL/6J-derived genomic segment on chromosome 19.

Allele

Symbol: Ccr1^tm1Gao
Name: targeted mutation 1, Ji-Liang Gao
MGI accession ID: MGI:1931850
Generation method: Targeted
Attributes: Null/Knockout
Synonyms: CCR1-
Marker symbol: Ccr1
Marker name: chemokine (C-C motif) receptor 1
Marker synonyms: CD191; CKR1; CKR-1; Cmkbr1; HM145; MIP1aR; SCYAR1
Chromosome: 9
Strain of origin: 129S4/SvJae
Molecular note: A neomycin resistance cassette replaced open reading frame sequences that correspond to 33% of the protein, from the third to the fifth transmembrane segment. Transcript was not detected in neutrophils of homozygous mutant animals.

Allele

Symbol: Ccr5^tm1Blck
Name: targeted mutation 1, Bruno Luckow
MGI accession ID: MGI:3613371
Generation method: Targeted
Attributes: Reporter; Null/Knockout
Synonyms: Ccr5^-
Marker symbol: Ccr5
Marker name: chemokine (C-C motif) receptor 5
Marker synonyms: CCCKR5; CC-CKR-5; CCR-5; CD195; Ckr5; CKR-5; Cmkbr5; IDDM22
Chromosome: 9
Strain of origin: 129P2/OlaHsd
Molecular note: A lacZ-neo cassette replaced much of the single exon. Absence of transcript was confirmed by RNase-protection assay.

Allele

Symbol: Apoe^tm1Unc
Name: targeted mutation 1, University of North Carolina
MGI accession ID: MGI:1857129
Generation method: Targeted
Attributes: Null/Knockout
Synonyms: AopE(-); apoE-; APOE KO; Apoe^tm1Un; apoE0; ApoE-KO; EKO; epsilon-; mE^-; mEKO
Marker symbol: Apoe
Marker name: apolipoprotein E
Marker synonyms: AD2; APO-E; ApoE4; APOEA; LDLCQ5; LPG
Chromosome: 7
Strain of origin: 129P2/OlaHsd
Molecular note: Insertion of a neomycin resistance cassette deleted part of exon 3 and part of intron 3 of the Apoe gene. Plasma from homozygous mutant mice gave no detectable immunoprecipitate by the Ouchterlony double immunodiffusion test using a rabbit antibody to rat APOE.