Anti-thyroid antibodies in Italian scleroderma patients: association of anti-thyroid peroxidase (anti-TPO) antibodies with HLA-DR15.
OBJECTIVE
To evaluate the frequency of anti-thyroid antibodies in a group of patients with scleroderma (SSc) and to analyze their genetic association with the HLA class II antigens.


METHODS
Anti-thyroglobulin (anti-TG) and anti-thyroid peroxidase (anti-TPO) antibodies were measured by hemagglutination techniques. Thyroid function was evaluated by determining the levels of FT3, FT4 and TSH. HLA-DR typing was carried out using a standard complement-dependent microlymphocytotoxicity test.


RESULTS
The proportions of patients with anti-TG and anti-TPO antibodies were 12% (10/85) and 19% (16/85) respectively. Two patients with anti-thyroid antibodies had overt hypothyroidism and shared the HLA-DR3 allele. The SSc subjects with anti-TPO antibodies showed a higher frequency of the HLA-DR15 allele than the patients without these antibodies.


CONCLUSIONS
A considerable number of patients with scleroderma have antibodies to thyroid antigens without exhibiting any alterations of their thyroid function. HLA-DR15 is an immunogenic marker for the formation of antibodies against microsomal thyroid peroxidase.
Molteni
M
M
Institute of Internal Medicine, Infectious Diseases and Immunopathology, University of Milan, IRCCS Ospedale Maggiore di Milano, Italy.
Barili
M
M
Eisera
N
N
Scrofani
S
S
Mascagni
B
B
Zulian
C
C
Scorza
R
R
D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers; D004264:DNA Topoisomerases, Type I / Q000235:genetics / Q000276:immunology; D005260:Female; D005819:Genetic Markers; D006684:HLA-DR Antigens / Q000276:immunology*; D059810:HLA-DR Serological Subtypes; D006801:Humans; D007453:Iodide Peroxidase / Q000235:genetics / Q000276:immunology*; D007558:Italy; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D012595:Scleroderma, Systemic / Q000276:immunology*; D013954:Thyroglobulin / Q000276:immunology
D001323:Autoantibodies; D015415:Biomarkers; D005819:Genetic Markers; D006684:HLA-DR Antigens; D059810:HLA-DR Serological Subtypes; C106559:HLA-DR15 antigen; D013954:Thyroglobulin; D007453:Iodide Peroxidase; D004264:DNA Topoisomerases, Type I