Title

Inflammation and autoimmunity caused by a SHP1 mutation depend on IL-1, MyD88, and a microbial trigger.

Document Type

Article

Publication Date

2008

Keywords

Animals, Autoimmune-Diseases, Autoimmunity, Ethylnitrosourea, Homozygote, Inflammation, Interleukin-1, Interleukin-1-Receptor-Associated-Kinases, Listeria-Infections, Mice-Mutant-Strains, Mutagenesis, Mutation, Myeloid-Differentiation-Factor-88, Protein-Tyrosine-Phosphatase-Non-Receptor-Type-6, Receptors-Interleukin-1, Toll-Like-Receptors

JAX Source

Proc Natl Acad Sci U S A 2008 Sep; 105(39):15028-33.

Abstract

A recessive phenotype called spin (spontaneous inflammation) was induced by N-ethyl-N-nitrosourea (ENU) mutagenesis in C57BL/6J mice. Homozygotes display chronic inflammatory lesions affecting the feet, salivary glands and lungs, and antichromatin antibodies. They are immunocompetent and show enhanced resistance to infection by Listeria monocytogenes. TLR-induced TNF and IL-1 production are normal in macrophages derived from spin mice. The autoinflammatory phenotype of spin mice is fully suppressed by compound homozygosity for Myd88(poc), Irak4(otiose), and Il1r1-null mutations, but not Ticam1(Lps2), Stat1(m1Btlr), or Tnf-null mutations. Both autoimmune and autoinflammatory phenotypes are suppressed when spin homozygotes are derived into a germ-free environment. The spin phenotype was ascribed to a viable hypomorphic allele of Ptpn6, which encodes the tyrosine phosphatase SHP1, mutated in mice with the classical motheaten alleles me and me-v. Inflammation and autoimmunity caused by SHP1 deficiency are thus conditional. The SHP1-deficient phenotype is driven by microbes, which activate TLR signaling pathways to elicit IL-1 production. IL-1 signaling via MyD88 elicits inflammatory disease.