First Author | Lin X | Year | 2013 |
Journal | J Immunol | Volume | 190 |
Issue | 7 | Pages | 3109-20 |
PubMed ID | 23427248 | Mgi Jnum | J:194526 |
Mgi Id | MGI:5474129 | Doi | 10.4049/jimmunol.1203422 |
Citation | Lin X, et al. (2013) Genetic Interactions among Idd3, Idd5.1, Idd5.2, and Idd5.3 Protective Loci in the Nonobese Diabetic Mouse Model of Type 1 Diabetes. J Immunol 190(7):3109-20 |
abstractText | In the NOD mouse model of type 1 diabetes, insulin-dependent diabetes (Idd) loci control the development of insulitis and diabetes. Independently, protective alleles of Idd3/Il2 or Idd5 are able to partially protect congenic NOD mice from insulitis and diabetes, and to partially tolerize islet-specific CD8(+) T cells. However, when the two regions are combined, mice are almost completely protected, strongly suggesting the existence of genetic interactions between the two loci. Idd5 contains at least three protective subregions/causative gene candidates, Idd5.1/Ctla4, Idd5.2/Slc11a1, and Idd5.3/Acadl, yet it is unknown which of them interacts with Idd3/Il2. Through the use of a series of novel congenic strains containing the Idd3/Il2 region and different combinations of Idd5 subregion(s), we defined these genetic interactions. The combination of Idd3/Il2 and Idd5.3/Acadl was able to provide nearly complete protection from type 1 diabetes, but all three Idd5 subregions were required to protect from insulitis and fully restore self-tolerance. By backcrossing a Slc11a1 knockout allele onto the NOD genetic background, we have demonstrated that Slc11a1 is responsible for the diabetes protection resulting from Idd5.2. We also used Slc11a1 knockout-SCID and Idd5.2-SCID mice to show that both loss-of-function alleles provide protection from insulitis when expressed on the SCID host alone. These results lend further support to the hypothesis that Slc11a1 is Idd5.2. |