Cutting Edge: Diabetes-Associated Quantitative Trait Locus, Idd4, Is Responsible for the IL-12p40 Overexpression Defect in Nonobese Diabetic (NOD) Mice

• Published in: The Journal of immunology (1950) 2003-10, Vol.171 (7), p.3333-3337
• Main Authors: Simpson, Pedro B, Mistry, Monica S, Maki, Richard A, Yang, Weidong, Schwarz, David A, Johnson, Eric B, Lio, Francisco M, Alleva, David G
• Format: Article
• Language: English
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.171.7.3333

APCs of the nonobese diabetic (NOD) mouse have a genetically programmed capacity to overexpress IL-12p40, a cytokine critical for development of pathogenic autoreactive Th1 cells. To determine whether a diabetes-associated NOD chromosomal locus (i.e., Idd) was responsible for this defect, LPS-stimulated macrophages from several recombinant congenic inbred mice with Idd loci on a C57BL/6 background or with different combinations of NOD and CBA genomic segments were screened for IL-12p40 production. Only macrophages from the congenic strains containing the Idd4 locus showed IL-12p40 overproduction/expression. Moreover, analysis of IL-12p40 sequence polymorphisms demonstrated that the Idd4 intervals in these strains contained the IL-12p40 allele of the NOD, although further analysis is required to determine whether the IL-12p40 allele itself is responsible for its overexpression. Thus, the non-MHC-associated Idd4 locus appears responsible for IL-12p40 overexpression, which may be a predisposing factor for type 1 diabetes in NOD mice.