Available to order

International strain nameC57BL/6-H2-Aatm1Blt/Cnrm
Alternative nameC57BL/6-H2-Aa
Strain typeTargeted Mutant Strains : Knock-out
Allele/Transgene symbolH2-Aatm1Blt,
Gene/Transgene symbolH2-Aa

Information from provider

ProviderHorst Bluethmann
Provider affiliationPharmaceuticals Divisons, F. Hoffmann-La Roche Ltd.
Genetic informationThe targeting vector was generated from a BamHI-XbaI fragment of the H2-Aab gene by introducing a neomycin resistance gene flanked by phosphoglycerate kinase-1 (pgk-1) promoter- and poly (A)+ signal sequences into a unique HindIII site in exon 2. The H2-Aa homologies provided at both sides of the neo cassette were 3 kb and 1 kb, respectively. The targeting vector was linearized before electroporation into embryonic stem cells derived from C57BL/6 mice.
Phenotypic informationIn mice of H-2b haplotype, a naturally occurring mutation in the Ea promoter region blocks the expression of Ea genes, and leads to the lack of Ea heterodimers on the surface of thymic epithelial and immune cells. The additional targeted disruption of the Aa gene completely prevents the expression of MHC class II molecules in B6-H2-Aatm1Blt mice. This leads to a severe reduction in the development of mature CD4+CD8- T cells in the thymus.
Breeding historyThe mutation was introduced in C57BL/6 ES cells. Heterozygous mutant mice were generated by crossing with C57BL/6 and intercrossed to generate a homozygous mutant strain.
  • Targeted disruption of the MHC class II Aa gene in C57BL/6 mice.;Köntgen F, Süss G, Stewart C, Steinmetz M, Bluethmann H, ;1993;International immunology;5;957-64; 8398989
Homozygous fertileyes
Homozygous viableyes
Homozygous matings requiredyes

Information from EMMA

Archiving centreCNR, Consiglio Nazionale delle Ricerche, Monterotondo, Italy

Disease and phenotype information

MGI phenotypes (allele matching)
  • enlarged lymph nodes / MGI
  • thymus hyperplasia / MGI
  • enlarged thymus / MGI
  • abnormal MHC II cell surface expression on macrophages / MGI
  • abnormal T cell morphology / MGI
  • decreased CD4-positive, alpha beta T cell number / MGI
  • increased CD8-positive, alpha-beta T cell number / MGI
  • abnormal splenocyte physiology / MGI

Literature references

  • Targeted disruption of the MHC class II Aa gene in C57BL/6 mice.;Köntgen F, Süss G, Stewart C, Steinmetz M, Bluethmann H, ;1993;International immunology;5;957-64; 8398989

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Requesting frozen sperm or embryos is generally advisable wherever possible, in order to minimise the shipment of live mice.

  • Frozen embryos. Delivered in 4 weeks (after paperwork in place). €1740*
  • Rederivation of mice from frozen stock, delivery time available upon request . €3880*

Due to the dynamic nature of our processes strain availability may change at short notice. The local repository manager will advise you in these circumstances.

* In addition users have to cover all the shipping costs (including the cost for returning dry-shippers, where applicable).

More details on pricing and delivery times

Practical information

Example health report
(Current health report will be provided later)

Material Transfer Agreement (MTA)
For this strain no provider MTA is needed. Distribution is based on the EMMA conditions only.

EMMA conditions
Legally binding conditions for the transfer

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