POLYCLONARL ANTIBODY DIRECTED AGAINST HOMOCYSTEINE THIOLACTONE MODIFIEDLDL

同型半胱氨酸血症被认为是导致这种疾病的原因。 然而，动脉粥样硬化的确切病因尚不清楚。我们 研究了同型半胱胺-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赖氨酸的反应 残留物，具有免疫原性。对新西兰大白兔进行免疫 每隔6周加成一次。抗体效价(约100,000) 在第三次免疫后收集的抗血清中检测到 采用固相酶联免疫吸附试验技术。在以竞争为基础的ELISA中， 同型半胱氨酸硫内酯处理的低密度脂蛋白竞争结合 抗血清，因为50%抑制浓度约为10 微克/毫升。既没有同型半胱氨酸、同型半胱氨酸，也没有铜(2+)氧化 低密度脂蛋白争相结合。低密度脂蛋白，其中赖氨酰残留量 通过乙酰化或甲基化衍生的不能被 抗血清。同型半胱氨酸的所有脂蛋白组分 硫代内酯处理后的血浆与抗血清竞争结合。我们 结论：同型半胱氨酸硫代内酯修饰的低密度脂蛋白高度 对同型半胱胺-赖氨酰加合物具有免疫原性和特异性。这 抗体有可能被用作一种诊断工具 血浆同型半胱氨酸的测定及其作用的研究 血管疾病中的同型半胱氨酸血症。

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.