The HLA-B44 model was generated by Pharmexa-Epimmune. The model was created by microinjecting a chimeric transgene combining a fragment of the genomic clone of the human HLA-B*4002 gene that included leader sequence, α1 and α2 domains ligated to a fragment of the murine H2-K^b gene containing the α3, transmembrane and cytoplasmic domains, all under the control of the murine H2-K^b promoter. This transgene was microinjected into C57BL/6 zygotes. The resultant mice from Founder Line B44.01 were on an inbred C57BL/6 background. The line was maintained by breeding hemizygotes to wild type C57BL/6NTac mice for 4 generations. Taconic received stock from Pharmexa-Epimmune in 2008. The line was embryo transfer derived by breeding C57BL/6NTac wild type females to hemizygous males and then was intracrossed to homozygosity. The colony is maintained through breeding of homozygous males to homozygous females. SNP profiles indicate that the strain is currently at 100% (NE10) on the C57BL/6NTac genetic background. In the production colony, wild type C57BL/6NTac females are bred to homozygous males on the C57BL/6NTac background to produce hemizygous pups on the C57BL/6NTac background. In addition, another production colony is breeding BALB/cAnNTac females with homozygous males on the C57BL/6NTAC background to product hemizygous CB6F1 pups, which are sold under model #9664.