Glyceraldehyde 3-phosphate dehydrogenase is a novel autoantigen leading autoimmune responses to proliferating cell nuclear antigen multiprotein complexes in lupus patients.

Abstract

Using 2-dimensional electrophoresis and ion-pair chromatography, we have identified elements of proliferating cell nuclear antigen (PCNA) multiprotein complexes that are reactive to antibodies in sera from patients with systemic lupus erythematosus. Among the various elements of the complexes, a 37 kDa protein (PI 8.5) that specifically reacted with SLE sera, but not with sera from patients with other connective tissue diseases, was identified as glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Immunoblot analysis showed that SLE sera reactive with the 37 kDa protein specifically reacted with GAPDH, as did anti-GAPDH mAbs. The purified autoantibodies to GAPDH from lupus serum showed both nuclear speckled and cytoplasmic staining patterns in immunofluorescence on Hep-2 cells. In addition, enzyme-linked immunosorbent assay (ELISA) revealed the presence of anti-GAPDH autoantibodies in 47% of lupus patients. Longitudinal analysis of the reactivity of lupus sera to PCNA complexes showed the autoimmune response to spread from GAPDH to other elements of PCNA complexes, and the presence of anti-GAPDH antibodies was significantly correlated with increased levels of serum PCNA. Taken together, these findings suggest that GAPDH interacting with PCNA in association with its cellular function is a novel autoantigen recognized by lupus sera, and that GAPDH thus plays an important role in the induction of autoimmune responses against the PCNA complex.

• Authors: Yoshinari Takasaki, Kazuhiko Kaneda, Masakazu Matsushita, Hirofumi Yamada, Masuyuki Nawata, Ran Matsudaira, Masanao Asano, Reiko Mineki, Noriko Shindo, Hiroshi Hashimoto
• Journal: International immunology (Int Immunol) Vol. 16 Issue 9 Pg. 1295-304 (Sep 2004) ISSN: 0953-8178 [Print] England
• PMID: 15262899 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antibodies, Monoclonal
• Autoantibodies
• Autoantigens
• Proliferating Cell Nuclear Antigen
• Glyceraldehyde-3-Phosphate Dehydrogenases

Topics

• Animals
• Antibodies, Monoclonal (immunology)
• Autoantibodies (biosynthesis)
• Autoantigens (immunology)
• Connective Tissue Diseases (immunology)
• Glyceraldehyde-3-Phosphate Dehydrogenases (immunology)
• Humans
• Longitudinal Studies
• Lupus Erythematosus, Systemic (immunology)
• Mice
• Mice, Inbred BALB C
• Proliferating Cell Nuclear Antigen (immunology)