申请人:Beechem Joseph
公开号:US20060160068A1
公开(公告)日:2006-07-20
The present invention provides ligand-detection reagents, ligand analogs and methods for determining the presence of a ligand in a sample. The ligand-detection reagent comprises a ligand-binding antibody and a ligand analog to form an antibody-ligand analog complex wherein the ligand analog is covalently bonded to a reporter molecule. This complex may additionally comprise a labeling protein non-covalently bonded to the antibody to form a ternary complex wherein the labeling protein comprises a monovalent antibody fragment or a non-antibody protein that is covalently bonded to a label moiety. The reporter molecule is either quenched by the ligand-binding antibody or by the label moiety of the labeling protein, depending on the reporter molecule and the ligand-binding antibody, wherein the amount of quenching is directly related to the amount of ligand present in the sample. Alternatively, the ligand analog is fluorogenic wherein the ligand analog is essentially non-fluorescent in solution but when bound by the ligand-binding antibody the detectable signal increases. In this instance a decrease in signal, as opposed to the relieving of quenching, is measured for the presence of a target ligand.
本发明提供了配体检测试剂、配体类似物和用于确定样品中配体存在的方法。该配体检测试剂包括一个配体结合抗体和一个配体类似物,形成一个抗体-配体类似物复合物,其中配体类似物与一个报告分子共价结合。该复合物还可以包括一个标记蛋白,非共价结合于抗体上,形成一个三元复合物,其中标记蛋白包括单价抗体片段或共价结合于标记基团的非抗体蛋白。报告分子可以被配体结合抗体或标记蛋白的标记基团熄灭,具体取决于报告分子和配体结合抗体,其中熄灭的程度与样品中配体的数量直接相关。或者,配体类似物是荧光原性的,其中配体类似物在溶液中基本上不发荧光,但当被配体结合抗体结合时,可检测的信号增加。在这种情况下,对于目标配体的存在,测量的是信号的降低,而不是熄灭的缓解。