The binding of anti-DNA antibodies to phosphorothioate oligonucleotides in a solid phase immunoassay.
Phosphorothioate oligonucleotides (S-oligos) are nucleic acid derivatives that are commonly used as antisense agents. These compounds, similar to bacterial DNA and CpG oligonucleotides, display a variety of immunological activities in vitro and in vivo. To assess further these activities, the antigenicity of a series of S-oligos was assessed in the solid phase using anti-DNA antibodies from sera of patients with systemic lupus erythematosus. By ELISA, S-oligos bound well to anti-DNA antibodies under the same conditions as calf thymus DNA antigen. The specificity for anti-DNA was established by competition assays showing cross-inhibition of binding by DNA and S-oligos. Reactivity with anti-DNA was observed with S-oligos varying in sequence, suggesting interaction with a conserved determinant not strictly dependent on the bases. Furthermore. in comparison with a phosphodiester oligomer of the same sequence, a phosphorothioate showed dramatically increased activity. These findings indicate that structural features associated with the S-oligo backbone promote specific binding to anti-DNA antibodies and influence the size requirement for antigenicity in the solid phase. These observations thus extend the immunological properties of S-oligos and suggest uses of these compounds in the diagnosis and treatment of autoimmune disease.
Pisetsky
D S
DS
Division of Rheumatology, Allergy and Clinical Immunology, Durham VA Hospital, NC 27705, USA.
Reich
C F
CF
D000818:Animals; D000974:Antibodies, Antinuclear / Q000097:blood / Q000378:metabolism*; D001483:Base Sequence; D001666:Binding Sites, Antibody / Q000276:immunology*; D002417:Cattle; D004277:DNA, Single-Stranded / Q000276:immunology / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D000939:Epitopes / Q000235:genetics / Q000276:immunology; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology; D016376:Oligonucleotides, Antisense / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D013873:Thionucleotides / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D013950:Thymus Gland / Q000737:chemistry
D000974:Antibodies, Antinuclear; D004277:DNA, Single-Stranded; D000939:Epitopes; D016376:Oligonucleotides, Antisense; D013873:Thionucleotides