BPI-ANCA is found in reactive arthritis caused by Yersinia and Salmonella infection and recognise exclusively the C-terminal part of the BPI molecule.
OBJECTIVE
To examine the prevalence, binding sites and functional interactions of antineutrophil cytoplasmic autoantibodies (ANCA) against the bactericidal/permeability increasing protein (BPI) in reactive arthritis (ReA).


METHODS
Sera were analysed for the occurrence of ANCA by indirect immunofluorescence microscopy (IIF) and ELISA. Binding sites were determined using BPI, lipopolysaccharid binding protein (LBP), and fusion proteins of both proteins in ELISA. In addition, the effect of antibodies on the antibiotic activity of BPI was examined.


RESULTS
BPI-ANCA was found in patients with Yersinia- and Salmonella-triggered ReA and directed against the C-terminal portion of BPI. Goat anti BPI antibodies recognising this part inhibited the antibiotic activity of BPI in vitro.


CONCLUSIONS
BPI-ANCA was associated with ReA triggered by Salmonella and Yersinia infection. Directed against the C-terminal part of BPI, it can potentially inhibit its antibiotic activity and might be useful to identify patients with infectious bowel disease prone to extraintestinal sequelae.
Schultz
H
H
Dept. of Rheumatology, Medical University of Lübeck, Germany.
Csernok
E
E
Nikkari
S
S
Toivanen
P
P
Toivanen
A
A
Gross
W L
WL
D000209:Acute-Phase Proteins; D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000906:Antibodies; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood*; D023181:Antimicrobial Cationic Peptides; D016918:Arthritis, Reactive / Q000097:blood* / Q000276:immunology; D001770:Blood Bactericidal Activity; D001798:Blood Proteins / Q000032:analysis* / Q000737:chemistry; D002352:Carrier Proteins / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006041:Goats / Q000276:immunology; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D008875:Middle Aged; D009500:Neutralization Tests; D000091402:Prohibitins; D012480:Salmonella Infections / Q000097:blood* / Q000276:immunology; D015009:Yersinia Infections / Q000097:blood* / Q000276:immunology; D000099231:Lipopolysaccharide-Binding Protein
D000209:Acute-Phase Proteins; D000906:Antibodies; D019268:Antibodies, Antineutrophil Cytoplasmic; D023181:Antimicrobial Cationic Peptides; D001798:Blood Proteins; D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D000091402:Prohibitins; D000099231:Lipopolysaccharide-Binding Protein; C000717331:PHB2 protein, human; C021623:bactericidal permeability increasing protein