Bispecific abs against modified protein and DNA with oxidized lipids.
4-Hydroxy-2-nonenal (HNE), a racemic mixture of 4R- and 4S-enantiomers, is a major product of lipid peroxidation and is believed to be largely responsible for the cytopathological effects observed during oxidative stress. HNE reacts with histidine to form a stable HNE-histidine Michael addition-type adduct possessing three chiral centers in the cyclic hemiacetal structure. We have previously raised the mAbs, anti-R mAb 310 and anti-S mAb S412, that enantioselectively recognized the R-HNE-histidine and R-HNE-histidine adducts, respectively, and demonstrated the presence of both epitopes in vivo. In the present study, to further investigate the anti-HNE immune response, we analyzed the variable genes and primary structure of these Abs and found that the sequence of R310 was highly homologous to anti-DNA autoantibodies, the hallmark of systemic lupus erythematosus. An x-ray crystallographic analysis of the R310 Fab fragment showed that the R-HNE-histidine adduct binds to a hydrophobic pocket in the antigen-binding site. Despite the structural identity to the anti-DNA autoantibodies, however, R310 showed only a slight crossreactivity with the native double-stranded DNA, whereas the Ab immunoreactivity was dramatically enhanced by the treatment of the DNA with 4-oxo-2-nonenal (ONE), an analog of HNE. Moreover, the 7-(2-oxo-heptyl)-substituted 1,N2-etheno-type ONE-2'-deoxynucleoside adducts were identified as alternative epitopes of R310. Molecular mimicry between the R-HNE-histidine configurational isomers and the ONE-DNA base adducts is proposed for the dual crossreactivity.
Akagawa
Mitsugu
M
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
Ito
Sohei
S
Toyoda
Kazuyo
K
Ishii
Yoshihisa
Y
Tatsuda
Emi
E
Shibata
Takahiro
T
Yamaguchi
Satoru
S
Kawai
Yoshichika
Y
Ishino
Kousuke
K
Kishi
Yusuke
Y
Adachi
Takahiro
T
Tsubata
Takeshi
T
Takasaki
Yoshinari
Y
Hattori
Nobutaka
N
Matsuda
Tsukasa
T
Uchida
Koji
K
D000447:Aldehydes / Q000276:immunology* / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D000974:Antibodies, Antinuclear / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D018033:Antibodies, Bispecific / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*; D001323:Autoantibodies / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D003429:Cross Reactions; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry / Q000187:drug effects / Q000276:immunology; D018736:DNA Adducts / Q000276:immunology; D003853:Deoxyribonucleosides / Q000737:chemistry / Q000276:immunology; D000939:Epitopes / Q000737:chemistry / Q000276:immunology; D007140:Immunoglobulin Fab Fragments / Q000737:chemistry / Q000276:immunology; D015227:Lipid Peroxidation; D008055:Lipids / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D051379:Mice; D018716:Molecular Mimicry / Q000276:immunology*; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D011506:Proteins / Q000737:chemistry / Q000276:immunology
D000447:Aldehydes; D000974:Antibodies, Antinuclear; D018033:Antibodies, Bispecific; D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D018736:DNA Adducts; D003853:Deoxyribonucleosides; D000939:Epitopes; D007140:Immunoglobulin Fab Fragments; D008055:Lipids; D011506:Proteins; D004247:DNA; C027576:4-hydroxy-2-nonenal