Abnormalities of serum antielastin antibodies in connective tissue diseases.
BACKGROUND
Antibodies (Abs) to alpha-elastin (elastin breakdown product) and tropoelastin (elastin precursor) are found in the serum of all human subjects and correlate with their respective serum peptide levels; however, peptide levels vary with age and some disease states. This study was undertaken to determine if serum elastin Abs, peptides, and elastin metabolism were altered in autoimmune diseases by detecting a changing ratio of serum anti-alpha:tropoelastin Ab levels.


METHODS
Serum from patients with a variety of connective tissue diseases, including 28 with systemic lupus erythematosus (SLE), 24 with scleroderma, 18 with rheumatoid arthritis (RA), 10 with polymyositis, and 39 with vasculitis, was compared with serum from 19 age-matched healthy subjects for levels of antitropoelastin and anti-alpha-elastin Abs.


RESULTS
We found an increase in IgG anti-alpha-elastin and a decrease in antitropoelastin Abs in the sera of patients with scleroderma (p < .02 and .00005) and SLE (p < .006 and .011). There was also a marked increase in anti-alpha-elastin Abs in patients with polyarteritis nodosa (p < .0005) and decreases in antitropoelastin Abs in patients with RA (p < .05), polymyositis (p < .01), and a variety of other vasculidities (p < .0003).


CONCLUSIONS
Abnormal variations in elastin metabolism may be detected in several connective tissue diseases by measuring ratios of alpha- and tropoelastin IgG Abs as markers of elastin degradation and synthesis.
Colburn
Keith K
KK
Jerry L. Pettis Memorial Veterans Medical Center, Loma Linda, CA 92350, USA.
Langga-Shariffi
Euly
E
Kelly
G Timothy
GT
Malto
Marilyn C
MC
Sandberg
Lawrence B
LB
Baydanoff
Stephan
S
Green
Lora M
LM
D000293:Adolescent; D000328:Adult; D000906:Antibodies / Q000097:blood*; D003240:Connective Tissue Diseases / Q000276:immunology* / Q000378:metabolism; D003429:Cross Reactions; D004549:Elastin / Q000276:immunology* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D014333:Tropoelastin / Q000276:immunology / Q000378:metabolism
D000906:Antibodies; D007074:Immunoglobulin G; D014333:Tropoelastin; D004549:Elastin