Abstract
The identification of antigenic targets in the retroocular autoimmune response of Graves’ ophthalmopathy is likely to increase our understanding of mechanisms underlying this disorder. While a number of putative autoantigens have been identified on the basis of molecular weight or cell of origin, a determination of the significance of these antigens is contingent upon an identification of the amino acid sequence. Our group has previously identified immunoreactive retroocular fibroblast (ROF) proteins recognized by thyrotropin receptor (hTSH-R) antisera (anti-p1), at molecular weights of 95, 71, 41, and 14–25 kDa. In the present study, proteins detected by anti-p1 and visualized by Ponceau staining were isolated and processed for microsequencing. Ponceau staining revealed dense bands at molecular weights of 14 and 23 kDa, and a weak band at 41 kDa. N-terminal sequencing was performed on the prominent band at approximately 23 kDa, showing it to be manganese Superoxide dismutase (MnSOD), a mitochondrial enzyme responsible for protection against oxygen free radical-associated cellular damage. Sequence comparison of MnSOD to the hTSH-R peptide, p1, revealed a linear segment of amino acid homology. Preincubation of anti-p1 with p1 blocked immunodetection of the 23 kDa band corresponding to MnSOD, and immunoprecipitation of ROF protein using anti-p1 yielded protein recognized by anti-MnSOD. Autoimmunity against human recombinant MnSOD was further assessed by ELISA. Patients with Graves’ disease (n = 53) had significantly higher ELISA indices than normal control subjects (n = 29), while patients with Hashimoto’s thyroiditis had intermediate values. These results document MnSOD autoantibodies in patients with Graves’ disease and suggest that this may result from an immune cross-reactivity between MnSOD and the TSH-receptor.
Similar content being viewed by others
References
Burch H.B., Wartofsky L. Graves’ ophthalmopathy: current concepts regarding pathogenesis and management. Endocr. Rev. 14: 747, 1993.
Burch H.B., Bahn R.S., Gorman C., Garrity J. Ophthalmopathy. In: Braveman L.E., Utiger R.D. (Eds), The Thyroid, ed. 7. Lippincott Publishing Company, Philadelphia, 1996, p. 536.
Bahn R.S., Heufelder A.E. Mechanisms of disease: Pathogenesis of Graves’ ophthalmopathy. N. Engl. J. Med. 329: 1468, 1993.
Bahn R.S., Gorman C.A., Johnson C.M., Smith T.J. Presence of antibodies in the sera of patients with Graves’ disease recognizing a 23 kilodalton fibroblast protein. J. Clin. Endocrinol. Metab. 69: 622, 1989.
Salvi M., Miller A., Wall J.R. Human orbital tissue and thyroid membranes express a 64 kDa protein which is recognized by autoantibodies in the serum of patients with thyroid-associated ophthalmopathy FEBS 232: 135, 1988.
Zhang Z-G., Salvi M., Miller N., Bernard N., Arthurs B., Wall J.R. Restricted tissue reactivity of autoantibodies to a 64-kDa eye muscle membrane antigen in thyroid associated ophthalmopathy. Clin. Immunol. Immunopathol. 62: 183, 1992.
Burch H.B., Sellitti D., Barnes S.G., Nagy E.V., Bahn R.S., Burman K.D. TSH receptor antisera for the detection of immunoreactive protein species in retroocular fibroblasts obtained from patients with Graves’ ophthalmopathy. J. Clin. Endocrinol. Metab. 78: 1384, 1994.
Nagy E.V., Burch H.B., Lukes Y.G., Carr F.E., Kosugi S., Kohn L.D., Burman K.D. Immunogenicity of a unique region of the human thyrotropin receptor. J. Endocrinol. Invest. 16: 485, 1993.
Ban T., Kosugi S., Kohn L.D. Specific antibody to the thyrotropin receptor identifies multiple receptor forms in membranes of cells transfected with wild-type receptor complementary deoxyribonucleic acid: characterization of their relevance to receptor synthesis, processing, structure, and function. Endocrinology 131: 815, 1992.
Kosugi S., Ban T., Akamizu T., Kohn L.D. Site-directed mutagenesis of a portion of the extracellular domain of the rat thyrotropin receptor important in autoimmune thyroid disease and nonhomologous with gonadotropin receptors. Relationship of functional and immunogenic domains. J. Biol. Chem. 266: 19413, 1991.
Endo T., Ikeda M., Ohmori M., Anzai E., Haraguchi K., Onaya T. Single subunit structure of the human thyrotropin receptor. Biochem. Biophys. Res. Commun. 187: 887, 1992.
Yen H.C., Oberly T.D., Vichitbandha S., Ho Y.S., St Clair D.K. The protective role of manganese Superoxide dismutase against adriamycin-induced acute cardiac toxicity in transgenic mice. J. Clin. Invest 98: 1253, 1996.
Oberley T.D., Coursin D.B., Cihla H.P., Oberley L.W., El-Sayyad N., Ho Y.S. Immunolocalization of manganese Superoxide dismutase in normal and transgenic mice expressing the human enzyme. Histochem. J. 25: 267, 1993.
Fernandez J., DeMott M., Atherton D., Mische S.M. Internal protein sequence analysis: enzymatic digestion for less than 10 micrograms of protein bound to polyvinylidene difluoride or nitrocellulose membranes. Anal. Biochem. 201: 255, 1992.
Lane W.S., Galat A., Harding M.W., Schreiber S.L. Complete Amino acid sequence of the FK506 and rapamycin binding protein, FKBP, isolated from calf thymus. J. Prot. Chem. 10: 151, 1991.
Mengistu M., Lukes Y.G., Nagy E.V., Burch H.B., Carr F.E., Lahiri S., Burman K.D. TSH receptor gene expression in retroocular fibroblasts. J. Endocrinol. Invest 17: 437, 1994.
Heufelder A.E., Dutton C.M., Bahn R.S. Detection of TSH receptor RNA in cultured retroocular fibroblasts from patients with Graves’ ophthalmopathy and pretibial myxedema. Thyroid 3: 297, 1993.
Feliciello A., Porcellini A., Ciullo I., Bonavolonta G., Awedimento E.V., Fenzi G.F. Expression of thyrotropin-receptor in RNA in healthy and Graves’ disease retroorbital tissues. Lancet 342: 337, 1993.
Paschke R., Metcalfe A., Alcade L., Vassart G., Weetman A., Ludgate M. Presence of nonfunctional thyrotropin receptor variant transcripts in retroocular and other tissues. J. Clin. Endocrinol. Metab. 79: 1234, 1994.
Dutton C.M., Natt N., Bahn R.S. Liquid hybridization analysis of TSH receptor mRNA in cultured fibroblasts from patients with Graves’ ophthalmopathy. 69th Annual Meeting of the American Thyroid Association, San Diego, California, November, 1996, Abstract 59.
Endo T., Onaya T. Thyrotropin receptor is expressed in nonthyroid tissues. Nippon Rinsho 52: 969, 1994.
Iwase K., Nagasaki A., Kato K., Ohtani S., Tsujimura T., Inagaki A., Jimbo S., Nakai A., Masunaga R., Hamada M., Mano T., Kotake M., Miura K. Localization of Cu/Zn and Mn Superoxide dismutase in various thyroid disorders. Acta Endocrinol. (Copenh.) 129: 573, 1993.
Pereira B., Costa Rosa L.F., Safi D.A., Bechara E.J. Control of Superoxide dismutase, catalase, and glutathione peroxidase activities in rat lymphoid organs by thyroid hormones. J. Endocrinol. 140: 73, 1994.
Nakamura Y., Makino R., Tanaka T., Ishimura Y., Ohtaki S. Mechanism of H2O2 production in porcine thyroid cells: Evidence for intermediary formation of superoxide anion by NADPH-dependent H2O2-generating machinery. Biochemistry 30: 4880, 1991.
Suzuki K., Kinoshita N., Matsuda Y., Higashiyama S., Kuzuya T., Minamino T., Tada M., Taniguchi N. Elevation of immunoreactive serum Mn-superoxide dismutase in patients with myocardial infarction. Free Radic. Res. Commun. 15: 325, 1992.
Ohno H., Matsuura N., Ishikawa M., Sato Y., Endo Y., Taniguchi N. Serum manganese-superoxide dismutase in patients with diabetes mellitus and thyroid dysfunction as judged by an ELISA. Horm. Metab. Res. 23: 449, 1991.
Ritter K., Kühl R-J., Semrau F., Eiffert H., Kratzin H.D., Thomssen R. Manganese Superoxide dismutase as a target of autoantibodies in acute Epstein-Barr virus infection. J. Exp. Med. 180: 1995, 1994.
Burch H.B., Lahiri S., Bahn R.S., Barnes S.G. Superoxide radical production stimulates retroocular fibroblast proliferation in Graves’ ophthalmopathy. Exp. Eye Res. 65: 311, 1997.
Nagy E.V., Burch H.B., Mahoney K., Lukes Y.G., Morris J.C., Burman K.D. Graves’ IgG recognizes linear epitopes in the human thyrotropin receptor. Biochem. Biophys. Res. Commun. 188: 28, 1992.
Vlase H., Graves P.N., Magnusson R.P., Davies T.F. Human antibodies to the thyrotropin receptor: Recognition of linear, folded, and glycosylated recombinant extracellular domain. J. Clin. Endocrinol. Metab. 80: 46, 1995.
Kiljanski J., Nebes V., Stachura I., Kennerdell J., Wall J.R. Should Graves’ disease be considered a collagen disorder of the thyroid, skeletal muscle, and the connective tissue? Horm. Metab. Res. 27: 528, 1996.
Author information
Authors and Affiliations
Additional information
The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense.
Rights and permissions
About this article
Cite this article
Burch, H.B., Barnes, S., Nagy, E.V. et al. Immunodetection of manganese superoxide dismutase in cultured human retroocular fibroblasts using sera directed against the thyrotropin receptor. J Endocrinol Invest 21, 48–55 (1998). https://doi.org/10.1007/BF03347286
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF03347286