Screening of a HUAEC cDNA library identifies actin as a candidate autoantigen associated with carotid atherosclerosis.
The humoral immune response to endothelium has a pivotal role in the development of atherosclerosis. Using a molecular method, we sought to identify endothelial autoantigens in carotid atherosclerosis. Immunoscreening of a HUAEC expression library with IgG from a pool of two sera from patients with carotid atherosclerosis identified a clone specific to actin. We evaluated actin-specific IgG reactivity in patients with carotid atherosclerosis and compared responses with those in patients with systemic lupus erythematosus and type 1 diabetes mellitus and in healthy subjects. Enzyme-linked immunoassay detected actin-specific IgG in a significantly higher percentage of sera from patients with atherosclerosis and systemic lupus erythematosus than from healthy subjects (16/61, 26% and 13/33, 39%versus 2/41, 5%, P = 0.012 and P < 10(-4), by chi2 test). Mean optical density values were significantly higher in patients than in healthy subjects (P < 10(-4) by Student's t-test). Patients with atherosclerosis and uncomplicated plaques had significantly higher serum anti-actin IgG reactivity than those with complicated plaques (P = 0.048 by Student's t-test). Our findings suggest that actin is an autoantigenic molecule of potential clinical interest in carotid atherosclerosis.
Margutti
P
P
Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome, Italy.
Delunardo
F
F
Sorice
M
M
Valesini
G
G
Alessandri
C
C
Capoano
R
R
Profumo
E
E
Siracusano
A
A
Salvati
B
B
Riganò
R
R
Ortona
E
E
D000199:Actins / Q000276:immunology*; D000328:Adult; D000368:Aged; D000906:Antibodies / Q000276:immunology; D001161:Arteriosclerosis / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology*; D002339:Carotid Arteries / Q000276:immunology*; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology; D004730:Endothelium, Vascular / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005455:Fluorescent Antibody Technique / Q000379:methods; D015723:Gene Library; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D008297:Male
D000199:Actins; D000906:Antibodies; D001324:Autoantigens; D007074:Immunoglobulin G