RESUMO
Antibodies raised against deoxyadenylate and deoxycytidylate were found to react with double stranded DNA as assessed by highly sensitive avidin-biotin microELISA. The binding was specific as it was completely inhibited by the homologous hapten. The antibodies did not react with tRNA and rRNA. These antibodies were also shown to react with supercoiled and relaxed forms of pBR322 DNA as demonstrated by gel retardation assay.
Assuntos
Anticorpos , DNA , Nucleotídeos de Desoxiadenina/imunologia , Desoxicitidina Monofosfato/imunologia , Nucleotídeos de Desoxicitosina/imunologia , Complexo Antígeno-Anticorpo , DNA/imunologia , Ensaio de Imunoadsorção Enzimática , Epitopos/análise , Cinética , MicroquímicaRESUMO
Populations of anti-DNA antibodies in two SLE plasma were defined based on their patterns of reactivity in inhibition assays with single and double-stranded DNA as well as mono- and oligonucleotides. Two populations of anti-DNA antibodies were seen in both plasma tested. The first population reacted specifically with ssDNA and was inhibited by relatively low concentrations of free nucleotides indicating that it recognized the nucleotide bases in ssDNA. The second population bound both ss and ds calf thymus DNA with apparent equal affinity. The cross-reactive anti-DNA antibodies were inhibited by mononucleotides (at high concentrations) and by single-stranded oligonucleotides (average length tetranucleotides). For one of the plasma tested (PS), pBR322 plasmid DNA (54% G + C) was a significantly more effective inhibitor than calf thymus DNA (39% G + C). These results suggested that nucleotide bases contributed to dsDNA binding by cross-reactive anti-DNA antibodies.
Assuntos
Anticorpos Antinucleares/imunologia , Especificidade de Anticorpos , DNA/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Reações Cruzadas , DNA de Cadeia Simples/imunologia , Nucleotídeos de Desoxiadenina/imunologia , Desoxicitidina Monofosfato/imunologia , Nucleotídeos de Desoxiguanina/imunologia , Humanos , Imunoglobulina G/imunologia , Timidina Monofosfato/imunologiaRESUMO
Antibodies raised in rabbits against deoxyguanylate and deoxycytidylate bind to 3H-lambda double stranded DNA and the binding is base specific. The concentrations of antibody populations that bind to double stranded DNA are much less than those binding to denatured DNA. Due to their low concentrations, these antibodies were not detected in earlier studies. These antibodies are expected to be useful to probe the conformational flexibilities of double stranded DNAs.
