Identification of streptococcal proteins reacting with sera from Behçet's disease and rheumatic disorders.
OBJECTIVE
We evaluated the reactivity of sera from Behçet's disease (BD), systemic lupus erythematosus (SLE), dermatomyositis (DM), rheumatoid arthritis (RA), and Takayasu's arteritis (TA) patients against human α-enolase and streptococcal α-enolase, and identified additional streptococcal antigens.


METHODS
Enzyme-linked immunosorbent assay (ELISA) and immunoblotting were performed using sera from patients with BD, SLE, DM, RA, and TA and healthy volunteers (control) against human α-enolase and streptococcal α-enolase. Immunoblot analysis and matrix-assisted laser desorption ionisation-time-of-flight mass spectrometry were used to identify and recombine other streptococcal antigens.


RESULTS
Specific positive signals against recombinant human α-enolase were detected by IgM ELISA of serum samples from 50% of BD, 14.3% of SLE, 57.1% of DM, 42.9% of RA, and 57.1% of TA patients. Specific positive signals against streptococcal α-enolase were detected from 42.9% of BD, 14.3% of DM, and 14.3% of TA patients. No SLE and RA sera reacted against streptococcal α-enolase antigen. Streptococcal proteins reacting with sera were identified as hypothetical protein (HP) for SLE and DM patients, acid phosphatase (AP) for RA patients, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) for TA patients.


CONCLUSIONS
We observed that RA patients did not present serum reactivity against either HP or GAPDH though BD, SLE, DM, and TA patients did. Also, AP reacted with sera from BD, SLE, DM, RA, and TA patients.
Cho
Sung Bin
SB
Department of Dermatology, Yonsei University College of Medicine, Seoul, Korea. sbcho@yuhs.ac
Lee
Ju Hee
JH
Ahn
Keun Jae
KJ
Cho
Suhyun
S
Park
Yong-Beom
YB
Lee
Soo-Kon
SK
Bang
Dongsik
D
Lee
Kwang Hoon
KH
D000135:Acid Phosphatase / Q000276:immunology; D000907:Antibodies, Bacterial / Q000097:blood* / Q000276:immunology; D000942:Antigens, Bacterial / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000276:immunology; D001426:Bacterial Proteins / Q000276:immunology*; D001528:Behcet Syndrome / Q000097:blood* / Q000276:immunology; D016022:Case-Control Studies; D003882:Dermatomyositis / Q000097:blood* / Q000276:immunology; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000276:immunology; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood* / Q000276:immunology; D010751:Phosphopyruvate Hydratase / Q000276:immunology; D013298:Streptococcus sanguis; D013625:Takayasu Arteritis / Q000097:blood / Q000276:immunology
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D000135:Acid Phosphatase; D010751:Phosphopyruvate Hydratase