This transgenic strain carries a rearranged Tcr alpha gene from the pathogenic anti-insulin CD4+ T-cell clone BDC12-4.1. Transgenic mice are viable and fertile. When hemizygotes are crossed with Stock No. 006304 NOD.FVB-Tg(TcrbBDC12-4.1)82Gse/GseJ, expression of the BDC12-4.1 T-cell receptor is confirmed by FACS analysis of PBMCs from the double transgenic mice. Double transgenic mice develop insulitis, but spontaneous diabetes does not develop, even in older animals (60 weeks of age), nor can insulin autoantibodies be detected in any age group. Splenocytes from double transgenic mice stimulated with B9-23 peptide produce IFN-gamma, whereas no response is observed in controls. When the congenic NOD double transgenic is combined with a homozygous Rag1tm1Mom mutation (such as in Stock No. 003729), recombination of the endogenous TCR and immunoglobulin genes is prevented. As a result, mature T cells in these mice express only the BDC12-4.1 TCR. In addition, approximately 50% of the double transgenic, Rag1tm1Mom homozygote mice develop diabetes by 30 weeks of age. Histopathology indicates severe insulitis and/or destruction of all insulin-producing cells (Jasinski et al 2006). This Tcr alpha transgenic strain when combined with the Tcr beta strain (Stock No. 006304) is useful for further studying the pathogenesis of insulin autoimmunity and diabetes.
In an attempt to offer alleles on well-characterized or multiple genetic backgrounds, alleles are frequently moved to a genetic background different from that on which an allele was first characterized. It should be noted that the phenotype could vary from that originally described. We will modify the strain description if necessary as published results become available.
