SLE Anti-DNA Autoantibodies Binding Estradiol-Albumin-DNA Conjugate

Abstract

The present study was designed to study the possible role of the female sex hormone, estradiol in conjugation with DNA, in the pathogenesis of systemic lupus erythematosus (SLE). Calf thymus DNA fragments (average size 200 bp) were covalently linked to estradiol-albumin (E₂-BSA) by treatment with glutaraldehyde. The conjugate was separated from free DNA by gel exclusion chromatography. It was characterized by UV spectroscopy and thermal denaturation studies. The conjugate (E₂-BSA-DNA) induced high titer antibodies which were highly specific towards their immunogen. These antibodies also recognize estradiol-albumin and B-estradiol but not native DNA (B-form), brominated DNA (Z-form) or poly(rG).poly(dC) (A-form). The E₂-BSA-DNA conjugate showed significant binding with SLE sera known to have a high level of anti-native DNA antibodies. The results indicated the recognition of unique conformation of estradiol-BSA-DNA conjugate by naturally occurring SLE anti-DNA autoantibodies.

Keywords

SLE Estradiol-albumin-DNA conjugate B-DNA Autoantibodies

Get full access to this article

View all access options for this article.

References

Lahita RG The importance of estrogens in systemic lupus erythematosus. Clin Immunol Immunopathol 1992; 63: 17-18.

Schwartz RS , Stollar BD Origin of anti-DNA autoàntibodies. J Clin Invest 1985; 75: 321-7.

Jungers P. , Dougados M. , Pelissier C. et al. Lupus nephropathy and pregnancy: report of 104 cases in 36 patients . Arch Intern Med 1982; 142: 771-6.

Jungers P. , Dougados M. , Pelissier C. et al. Influence of oral contraceptive therapy on the activity of systemic lupus erythematosus. Arthritis Rheum 1982; 25: 618-23.

Siiteri PK , Jones LA , Roubinian JR , Talal N. Sex steroids and the immune system: sex difference in autoimmune disease in NZB/NZW hybrid mice. J Steroid Biochem 1980 ; 12: 425-31.

Bucala R. , Lahita RG , Fishman J. , Cerami A. Anti-estrogen antibodies in users of oral contraceptives and in patients with systemic lupus erythematosus. Clin Exp Immunol 1987; 67: 167-75.

Lehar SC , Settineri SM , Kelly RH Anti-hormonal and anti-nuclear (ANA) responses of mice immunized with estradiol . Immunol Invest 1987; 16: 117-28.

Counihan KA , Vertosick FT , Kelly RH Anti-estrogen antibodies in systemic lupus erythematosus: a quantitative evaluation of serum levels. Immunol Invest 1991; 20: 317-31.

Ali R. , Dersimonian H. , Stollar BD Binding of monoclonal anti-native DNA autoantibodies to DNA of varying size and conformation. Mol Immunol 1985; 22: 1415-22.

10.

Reichlin M. Coupling peptides to carrier proteins using glutaraldehyde. In: Harlow Ed , Lane D , eds. Antibodies - A Laboratory Manual. USA: Cold Spring Harbor Laboratory, 1988: 78.

11.

Hasan R. , Ali R. Antibody recognition of common epitopes on Z-DNA and native DNA brominated under high salt. Biochem Int 1990; 20: 1077-88.

12.

Alam K. , Ali A. , Ali R. The effect of hydroxyl radical on the antigenicity of native DNA. FEBS Lett 1993; 319: 66-70.

13.

Ishaq M. , Ali R. Identical specificity of lupus antibodies and antibodies elicited in rabbits against Sm and RNP antigens. Immunol Commun 1984; 13: 447-55.

14.

Ali A. , Ali R. Enzyme-linked immunosorbent assay for anti-DNA antibodies using fluorogenic and colorigenic substrates. J Immunol Methods 1983; 56: 341-6.

15.

Ara J. , Ali R.

Assay of antinuclear antibodies by ELISA using nuclei as antigen. Eur

J Clin Chem Clin Biochem 1993; 31: 289-93.

16.

Ali A. , Hasan R. , Ali R. Antigen binding diversity of affinity purified autoantibodies against DNA . Biochem Int 1991; 23: 111-18.

17.

Burton K. A study of the conditions and mechanism of the diphenylamine reaction for the colorimetric estimation of deoxyribonucleic acid. Biochem J 1956; 62: 315-23.

18.

Lowry OH , Rosenberg NJ , Farr AL , Randall RJ Protein measurement with Folin phenol reagent. J Biol Chem 1951; 193: 265-75.

19.

Carlsten H. , Tarkowski A. , Holmdahl R. , Nilson LA Oestrogen is a potent disease accelerator in SLE-prone MRL lpr/lpr mice. Clin Exp Immunol 1990; 80: 467-73.

20.

Steinberg AD Concepts of pathogenesis of systemic lupus erythematosus . Clin Immunol Immunopathol 1992; 63: 19-22.

21.

Ara J. , Ali R. Reactive oxygen species modified DNA fragments of varying size are the preferred antigen for human anti-DNA autoantibodies. Immunol Lett 1992; 34: 195-200.

22.

Ara J. , Ali A. , Ali R. Antibodies against free radical modified native DNA recognize B-conformation . Immunol Invest 1992; 21: 553-63.

23.

Ara J. , Ali R. Polynucleotide specificity of anti-reactive oxygen species (ROS) DNA antibodies . Clin Exp Immunol 1993; 94: 134-9.