In addition to the H2k2 allele, this strain also carries the TL-18a variant allele of the thymic leukemia or TL antigen. This strain was derived from cryopreserved embryos of Stock No. 000465 because they predated an observed phenotypic change in the 000465 strain. Specifically a change in the CD4/CD8 T cell ratios and an increase in splenic leukocyte cellularity and a conspicuous elevation in cells of the monocyte lineage, was observed in that strain around 2003.Read More +
In approximately 2003 some phenotypic parameters of the B10.BR-H2k2 H2-T18a/SgSnJ mice were found to have changed relative to the strain's previous performance. In order to confirm that a change had occurred and in order to better characterize any differences that may have arisen, animals were recovered from cryopreserved embryos of the strain (Stock No. 004804) that had been frozen in 1991, and the two lines of B10.BR-H2k2 H2-T18a/SgSnJ were compared. This strain, which was the cryopreserved bankstock of 1991 that was recovered in approximately 2004, has the original phenotype and does not have the shift in the CD4/CD8 T cell ratios to an increased percentage of CD8 postitive T cells that is found in stock #465, the strain which has been continuously maintained live. Stock #465 also differs from this strain by having an increase in splenic leukocyte cellularity and a conspicuous elevation in cells of the monocyte lineage. Both colonies of B10.BR-H2k2 H2-T18a/SgSnJ (Stock No's. 000465 and 004804) may exhibit white belly spots; these spots are considered a strain characteristic.
In 1965 Jack H. Stimpfling and Alberta Richardson reported making this congenic strain in which the H2 haplotype was backcrossed from C57BR/cdJ onto C57BL/10ScSn. This congenic was fixed homozygous at N9. In 1980 this congenic reached generation N9F34 and in 1991 embryos were generated for cryopreservation from males and females at generation N9F50 and N9F51. After cryoprservation the strain was maintained on the shelf as stock #00465 and in approximately 2003 a phenotypic deviation was noticed. The 1991 cryopreserved bankstock, which pre-dated the phenotypic deviation, was then cryorecovered and assigned stock #004804. In 2012 this strain reached generation N9F52p+F19.
|Allele Name||k2 variant|
|Allele Type||Not Applicable|
|Gene Symbol and Name||H2, histocompatibility-2, MHC|
|Strain of Origin||Not Specified|
|Molecular Note||The H2k2 haplotype differs from the prototype H2k in having the a, rather than the canonical b, alleles of the Class Ib genes T18 (formerly Tla) and Qa-1. The H2k2 haplotype is shared by the inbred strains C57BR/cdJ and C58/J and the H2 congenic strain B10.BR-H2k2 H2-T18a/SgSnJ (formerly B10.BR-H2k/SgSnJ).|
|Allele Name||a variant|
|Allele Type||Not Applicable|
|Gene Symbol and Name||H2-T18, histocompatibility 2, T region locus 18|
|Strain of Origin||Not Applicable|
|Molecular Note||The allele H2-T18a determines presence of the antigenic specificities TL.1, 2, 3, 5, 6, 7 and occurs in strains A, C57BR, C58, SJL, and others.|
When using the B10.BR mouse strain in a publication, please cite the originating article(s) and include JAX stock #004804 in your Materials and Methods section.