Immunochemical evidence supporting 2-pentylpyrrole formation on proteins exposed to 4-hydroxy-2-nonenal.
Previous model studies suggested the formation of lysine-based 2-pentylpyrroles as novel late adduction products formed upon exposure of proteins to the lipid peroxidation product 4-hydroxy-2-nonenal (HNE). Two 2-pentylpyrrole immunogens were prepared, one by treating keyhole limpet hemocyanin (KLH) directly with 4-oxononanal and the other by preformation of 6-(2-pentylpyrrol-1-yl)hexanoic acid from 6-aminocaproic acid and 4-oxononanal, followed by carbodiimide coupling to KLH. Pyrrole content and lysine modification in KLH were assayed independently. Following immunization of rabbits, antibody titer increased and plateaued over a 4 month period. The structural specificity of the IgG fractions of the antisera was evaluated through comprehensive competitive ELISA studies. These antibodies were used to verify the time-dependent appearance of the 2-pentylpyrrole epitope in protein exposed to HNE. Potential advantages of antibodies recognizing "advanced lipid peroxidation end products" over those recognizing "early" HNE adduction products are discussed.
Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106, USA. lms3@po.cwru.edu
L M
LM
Sayre
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W
Sha
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Xu
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Kaur
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Nadkarni
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Subbanagounder
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Salomon
D000447:Aldehydes / Q000737:chemistry / Q000276:immunology / Q000633:toxicity*; D000818:Animals; D000906:Antibodies / Q000737:chemistry; D003432:Cross-Linking Reagents; D000939:Epitopes / Q000737:chemistry; D007120:Immunochemistry; D011506:Proteins / Q000737:chemistry / Q000187:drug effects* / Q000276:immunology*; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry; D011817:Rabbits
D000447:Aldehydes; D000906:Antibodies; D003432:Cross-Linking Reagents; D000939:Epitopes; D011506:Proteins; D011758:Pyrroles; C027576:4-hydroxy-2-nonenal