L-685458 (L-685,458) is a specific and potent inhibitor of A beta PP gamma-secretase activity with Ki of 17 nM.

γ-secretase:17 nM(Ki)

L-685,458在过表达人类AβPP695的Neuro2A和CHO细胞系，以及过表达spβA4CTF构建体的SHSY5Y细胞中抑制Aβ(40)形成，IC50分别为402 nM、113 nM和48 nM。[1] 在Tca8113细胞中，L-685,458通过诱导G0-G1细胞周期阻滞和凋亡抑制细胞生长。[2] 在一种T细胞急性淋巴细胞性白血病细胞系中，预处理L-685,458增强了伊马替尼的抗增殖效果。[3] L-685,458还通过抑制信号肽肽酶(SPP)显著减少组织培养中HSV-1的复制。[4]

HTRF Immunoassay for Aβ Quantitation: Homogeneous time-resolved fluorescence (HTRF) immunoassay methodology uses fluorescence resonance energy transfer (FRET) between two fluorophores, a donor EuK and a modified allophycocyanine pigment acceptor molecule, XL-665. When in proximity, nonradiative FRET takes place from nitrogen laser-excited EuK to XL-665, resulting in the emission of an amplified long-lived fluorescence signal. Briefly, in a typical 96-well plate assay, each well contains 0.75 nM antibody-EuK, 1.0 nM antibody-biotin, 2.0 nM SA-XL665, and 0.1?0.2 M potassium fluoride. Samples of conditioned cell culture medium or synthetic peptide standards and culture medium alone are added to give a total assay volume of 200 μL/well. Blank values are determined by the inclusion of 1.0 nM nonbiotinylated antibody in place of the biotinylated antibody. Following mixing, the reaction mixture is left at 4 °C to reach equilibrium binding, and then read on the Discovery HTRF microplate analyzer using the manufacturer's recommended settings.

The in vitro growth rate of Tca8113 cells treated with L-685,458, is measured by MTT. Briefly, Tca8113 cells are seeded in 96-well plates. On the day of harvest, 100 μL of spent medium is replaced with an equal volume of fresh medium containing 10% MTT 5 mg ml?1 stock. Plates are incubated at 37°C for 4 h, then 100 μl of DMSO is added to each well, and then plates are shaken at room temperature for 10 min. The absorbance is measured at 570 nm.(Only for Reference)