POLYCLONAL ANTIBODY DIRECTED AGAINST HOMOCYSTEINE THIOLACTONE MODIFIED LDL

同型半胱氨酸血症被认为是导致 然而，动脉粥样硬化的确切病因尚不清楚。 我们 研究了同型半胱氨酸-低密度脂蛋白加合物的可能性， 同型半胱氨酸硫内酯与载脂蛋白B赖氨酰之间的反应 残基，具有免疫原性。 免疫新西兰白色兔 每隔6周注射一次 抗体滴度（ca. 10万人） 在第三次免疫后收集的抗血清中测定 使用固相ELISA技术。 在基于竞争的ELISA中， 同型半胱氨酸硫代内酯处理的LDL竞争与 抗血清，因为50%抑制浓度约为10 微克/毫升。 同型半胱氨酸、同型胱氨酸和Cu（2+）均未氧化 LDL竞争结合。 其中赖氨酰残基 通过乙酰化或甲基化衍生的，不被识别， 抗血清 来自同型半胱氨酸的所有脂蛋白组分 硫内酯处理的血浆竞争结合抗血清。 我们 结论是同型半胱氨酸硫代内酯修饰的LDL是高度 免疫原性且对高胱氨酸-赖氨酰加合物具有特异性。 这 抗体有可能被用作诊断工具， 测量血浆同型半胱氨酸和描绘的作用， 血管疾病中同型半胱氨酸血症

Homocysteinemia is presumed to be responsible for the development of atherosclerosis, however, the precise etiology is unclear. We examined the possibility that the homocystamide-LDL adduct, a product of the reaction between homocysteine thiolactone and apo-B lysyl residues, was immunogenic. New Zealand white rabbits were immunized with this adduct at 6-week intervals. Antibody titers (ca. 100,000) were determined in antisera collected following the third immunization using solid-phase ELISA techniques. In competition-based ELISAs, homocysteine thiolactone-treated LDL competed for binding with the antiserum, as the 50% inhibitory concentration was approximately 10 micrograms/ml. Neither homocysteine, homocystine, nor Cu(2+)-oxidized LDL competed for binding. LDL in which lysyl residues were derivatized by acetylation or methylation were not recognized by the antiserum. All lipoprotein fractions from homocysteine thiolactone-treated plasma competed for binding to the antiserum. We conclude that homocysteine thiolactone-modified LDL is highly immunogenic and specific for homocystamide-lysyl adducts. This antibody has the potential to be used as a diagnostic tool for measuring plasma homocysteine and for delineating the role of homocysteinemia in vascular disease.