DNA, antibodies reacting with native

The first description of antibodies against polynucleotides was that of the anti-DNA antibody. Such antibodies, in sera of patients, were demonstrated by precipitation, by complement fixation, and by hemagglutination techniques (Seligmann, 1957 Ceppelini et al., 1957 Seligmann and Milgrom, 1957 Robbins et al., 1957). 

Although exceptional, the existence of antibodies with limited specificity for native DNA shows that the double-helical structure of the molecule could be an inherent part of the antigenic determinant. The role of the native conformation of DNA in these immunological reactions was shown both by the 

The anti-native DNA antibodies react equally well with DNAs which differ in their composition (DNA from mammalian cells, bacteria or virus) and thus it is unlikely that base sequence determinants are recognized, and specificity is essentially conformation-dependent. Antibodies reacting with native DNA have been described in several other human diseases (Koffler et al., 1969 Monier et al., 1970). However, the level was very low and their specificity has not been studied. 

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With the objective of obtaining antibodies reacting with native DNA, Stollar (1970) immunized rabbits with complexes of polydeoxyribonucleo-tides such as poly dG poly dC — MBSA, poly dAT — MBSA and the hybrid... 

Antibodies to mono-, di-, and trinucleotides of the usual nucleic acid bases react with denatured DNA but not with native DNA, in which the bases are not accessible. It has been difficult in many cases to measure their reactions with ribosomal RNA or single-stranded viral RNA, partly because of the extensive secondary and tertiary folding that may mask many of the bases and partly because of the difficulty in removing all ri-bonuclease from serum. Some reaction with RNA was measurable with an antiadenosine serum after careful efforts were made to remove ribonu-clease. Antibodies to anticodon sequences reacted with tRNA, as did antibodies to modified bases of tRNA and antibodies occurring spontaneously in sera of NZB/NZW mice or human patients with systemic lupus erythematosus. ... 

Immunization with denatured DNA-MBSA gives rise to antibodies, often mainly of the IgM class, that react with single-stranded DNA but not with native DNA. The largest antigenic determinant for such antibodies is about the size of a pentanucleotide. When DNA with an unusual base, such as the glucosylated hydroxymethylcytosine of T-even phage, is used, the specificity is directed largely to the modified base and much more IgG may be produced.Similarly, when UV-irradiated DNA or photooxidized DNA is used, the modified bases of the lesions provide the major specificity determinants. - ... 

Patients with systemic lupus erythematosus produce antibodies that react with duplex DNA. These antibodies hardly distinguish native from denatured DNA. Experimentally produced antibodies to RNA helices or RNA DNA hybrids, triple helices, or left-handed Z-DNA can be highly specific (Stollar, 1975, 1985). 

Fig. 3 represents trypsin digestion fragments of the poly(ADP-ribose) polymerase. Tbe C 9 antibody reacted with die native enzyme (116 K), the 46 K and 29 K ftagments (Fig. 3, blot 4). Zn and labelled DNA (in Fig. 3, blot 5 and blots 6,7, respectively) bound to the exact same fragments but did not bind to the 36 K fragment. 

With the exception of antibodies reacting only with native DNA all the different kinds of anti-polynucleotide antibodies described above can be induced experimentally. 

K9. Koren, E., Koscec, M., Wolfson-Reichlin, M., Ebling, F. M., Tsao, B., etal., Murine and human antibodies to native DNA that cross-react with the A and D SnRNP polypeptides cause direct injury of cultured kidney cells. J. Immunol. 154, 4857-4864 (1995). 

Narrower specificities have been obtained with antibodies to some unusual helical structures. Poly(dG)-poly(dC) induces antibodies specific for the immunogen and unreactive with other deoxyribonucleotide polymers, such as poly(dAT) or native DNA. Double-helical polyribonucleotides with modified furanoses, such as poly(A)-poly(2 -0-methylU), induce antibodies that react with a number of polymers bearing 2 -furanose substitutions (such as methyl or ethyl groups on either the purine or pyrimidine-containing strand). Poly(G)-poly(C) induced antibodies of narrow specificity in our studies, but Lacour and co-workers obtained anti-poly(G)-poly(C) that cross-reacted with several forms of viral RNA. ... 

Although the anti-poly G poly C sera react with poly dG poly dC, no precipitation with Micrococcus lysodeikticus DNA (72% GC) is observed, whether native or heat-denatured DNA is used. Negative results are also obtained with native or denatured DNA from E, coli, Clostridium j>erfringens, phage 2 C, chicken myeloblastic leukemic cells or calf thymus. In contrast, antibodies to poly G poly C react with RNA and appear to be capable of distinguishing ribonucleic acids according to their origin. 

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