title: Polydeoxyribonucleotide C photoconjugated with lysine or arginine present unique epitopes for human anti-DNA autoantibodies.
abstract: Studies have been carried out to synthesize and characterize the photoconjugates between positively charged amino acids (lysine and arginine) and the polydeoxyribonucleotide C [poly(dC)]. Poly(dC) was covalently crosslinked with lysine or arginine under ultraviolet light. Both lysine and arginine were found covalently photoconjugated to poly(dC), resulting in the formation of photoadduct. Photoaddition of lysine or arginine to poly(dC) rendered them thermodynamically more stable than their native form. A strong recognition of photoadducts was observed with anti-DNA autoantobodies found in the sera of systemic lupus erythematosus (SLE) patients. Poly(dC)-lysine was recognized more strongly than poly(dC)-argine photoadduct. Poly(dC)-lysine photoadduct appears to provide an immunodominant epitope for SLE autoantibody recognition. The result suggests for the possible involvement of these photoadducts as a potential trigger for anti-DNA autoantibody production.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, J.N. Medical College, Aligarh, India.
authors.forename: Kiran
authors.initials: K
authors.lastname: Dixit
authors.forename: Haseeb
authors.initials: H
authors.lastname: Ahsan
authors.forename: Asif
authors.initials: A
authors.lastname: Ali
mesh_terms: D000974:Antibodies, Antinuclear / Q000276:immunology* / Q000378:metabolism; D001120:Arginine / Q000737:chemistry*; D001323:Autoantibodies / Q000276:immunology / Q000378:metabolism; D003596:Cytosine / Q000378:metabolism*; D018736:DNA Adducts / Q000737:chemistry / Q000276:immunology*; D000939:Epitopes / Q000276:immunology*; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D008239:Lysine / Q000737:chemistry*; D011066:Poly C / Q000737:chemistry / Q000276:immunology*; D011089:Polydeoxyribonucleotides / Q000276:immunology; D013696:Temperature; D013816:Thermodynamics; D014466:Ultraviolet Rays
chemical_list: D000974:Antibodies, Antinuclear; D001323:Autoantibodies; D018736:DNA Adducts; D000939:Epitopes; D011089:Polydeoxyribonucleotides; C023826:poly(dC); D011066:Poly C; D003596:Cytosine; D001120:Arginine; D008239:Lysine