Anti-lactoferrin antibodies in patients with connective tissue diseases.
OBJECTIVE
To study the prevalence of antineutrophil cytoplasmic antibodies against lactoferrin in patients with connective tissue diseases and to characterize the antibody response to lactoferrin in these patients.


METHODS
Sera from 60 patients with systemic lupus erythematosus, 98 with rheumatoid arthritis, 11 with systemic sclerosis, and 6 with mixed connective tissue disease were studied. The presence of anti-lactoferrin antibodies was detected by enzyme-linked immunosorbent assay. The IgG subclass reactivity of antibodies to lactoferrin was analyzed by biotin-extravidin amplified enzyme-linked immunosorbent assay and monoclonal antibodies to human IgG subclasses.


RESULTS
Anti-lactoferrin antibodies were found in 15 patients (5 patients with rheumatoid arthritis and 10 with systemic lupus erythematosus). IgG1 was the predominant subclass for antibodies to lactoferrin.


CONCLUSIONS
Patients with connective tissue diseases are known to develop multiple auto-antibodies; anti-lactoferrin antibodies mainly of IgG1 isotype can also be found in patients with rheumatoid arthritis and more often in patients with systemic lupus erythematosus.
Laboratory of Clinical Immunology, Department of Molecular Biology, Immunology and Medical Genetics, Faculty of Medicine, Thracian University, Stara Zagora, Bulgaria.
Irena M
IM
Manolova
D000293:Adolescent; D000328:Adult; D000368:Aged; D000888:Antibodies, Anti-Idiotypic / Q000032:analysis / Q000276:immunology*; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003240:Connective Tissue Diseases / Q000175:diagnosis* / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007781:Lactoferrin / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011336:Probability; D011379:Prognosis; D012016:Reference Values; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
D000888:Antibodies, Anti-Idiotypic; D015415:Biomarkers; D007074:Immunoglobulin G; D007781:Lactoferrin