Enzyme-linked immunosorbent assay for anti-tropomyosin antibodies and its clinical application to various heart diseases.
Tropomyosin is one of the key proteins for muscle contraction. We developed an enzyme-linked immunosorbent assay for antibodies to porcine muscle tropomyosin and measured serum anti-tropomyosin antibodies in patients with heart diseases and in normal controls. The mean values of absorbance in the ELISA assay of patients with ischemic heart disease (n=36, P<0.001), dilated cardiomyopathy (n=28, P<0.005), valvular heart disease (n=27, P<0.05), and collagen disease (n=38, P<0.05) were significantly higher than those of normal controls (n=53), but the value in patients with hypertrophic cardiomyopathy (n=19) was not significantly different from that of normal controls. When the cut-off value was fixed at the mean+2 SD of absorbance in normal controls, positive reactions were found in 19.4%, 7.1%, 18.5% and 15.8% of patients with ischemic heart disease, dilated cardiomyopathy, valvular heart disease, and collagen disease, respectively. An inhibition study revealed that anti-tropomyosin antibodies were different from anti-myosin antibodies, but there was a partial cross-reactivity between the two. Thus, there was a weak correlation of the titers of the two types of antibody within the group of heart diseases. These data indicate that measurement of anti-tropomyosin antibodies by ELISA is helpful for detecting autoimmune abnormalities in various heart diseases.
Fujita
A
A
Department of Laboratory Medicine D2, Osaka University Medical School, 565-0871, Osaka, Japan.
Kuroda
S
S
Tada
H
H
Hidaka
Y
Y
Kimura
M
M
Takeoka
K
K
Nagata
S
S
Sato
H
H
Amino
N
N
D000328:Adult; D000368:Aged; D000906:Antibodies / Q000032:analysis*; D000918:Antibody Specificity; D000941:Antigens / Q000737:chemistry / Q000302:isolation & purification; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D019085:Fluorescent Antibody Technique, Direct; D006331:Heart Diseases / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009218:Myosins / Q000737:chemistry / Q000276:immunology; D014335:Tropomyosin / Q000276:immunology* / Q000302:isolation & purification
D000906:Antibodies; D000941:Antigens; D014335:Tropomyosin; D009218:Myosins