Transglutaminase 2: a novel autoantigen in canine idiopathic central nervous system inflammatory diseases.

Abstract

Necrotizing meningoencephalitis (NME), necrotizing leukoencephalitis (NLE) and granulomatous meningoencephalomyelitis (GME) are common idiopathic inflammatory central nervous system (CNS) diseases with unknown etiology in dogs. We previously showed that IgG autoantibodies in the cerebrospinal fluid (CSF) of NME cases reacted to unknown brain proteins as well as to glial fibrillary acidic protein (GFAP). In the present report, we evaluated the autoantibodies against transglutaminase2 (TG2) in the canine CNS diseases. CSF samples obtained from dogs with NME (n=19), NLE (n=7), GME (n=11) and miscellaneous CNS diseases (n=12) were subjected. CSFs from 20 healthy dogs were used as controls. Indirect fluorescent antibody test on the canine cerebrum revealed astrocyte-binding IgG in the CSF of NME. After absorption of the CSF with bovine GFAP, the CSF still possessed the reactivity to astrocytes. Double-color staining showed clear colocalization of the autoantibodies and anti-human TG2 rabbit polyclonal IgG. An immunoblot assay against human recombinant TG2 revealed anti-TG2 IgG in the CSF from dogs with NME, NLE and GME. The CSF of canine idiopathic encephalitis cases, notably of NME, tended to show high ELISA OD values against human recombinant TG2 compared to healthy controls. The presence of anti-TG2 autoantibodies in the CSF may contribute to the elucidation of the etiology of canine NME, NLE and GME.

• Authors: Miho Tanaka, Akiko Inoue, Kei Yamamoto, Satoshi Tamahara, Naoaki Matsuki
• Journal: The Journal of veterinary medical science (J Vet Med Sci) Vol. 74 Issue 6 Pg. 733-7 (Jun 2012) ISSN: 1347-7439 [Electronic] Japan
• PMID: 22230982 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Autoantigens
• Glial Fibrillary Acidic Protein
• Immunoglobulin G
• Recombinant Proteins
• Protein Glutamine gamma Glutamyltransferase 2
• Transglutaminases
• GTP-Binding Proteins

Topics

• Animals
• Autoantigens (metabolism)
• Dog Diseases (enzymology)
• Dogs
• Encephalitis (enzymology)
• Enzyme-Linked Immunosorbent Assay
• Fluorescent Antibody Technique, Indirect
• GTP-Binding Proteins (cerebrospinal fluid)
• Glial Fibrillary Acidic Protein (metabolism)
• Humans
• Immunoblotting
• Immunoglobulin G (metabolism)
• Protein Glutamine gamma Glutamyltransferase 2
• Recombinant Proteins (metabolism)
• Transglutaminases (cerebrospinal fluid)