Leupeptin hemisulfate is a protease inhibitor with cell membrane-permeable, reversible, competitive, and oral activities. Leupeptin hemisulfate inhibits the activity of Cathepsin B, Cathepsin H, and Cathepsin L, and blocks fusion of amphipathic lysosomes. Leupeptin hemisulfate also has anti-inflammatory activity.

方法：SARS-CoV-2 感染的 Vero 细胞用 Leupeptin hemisulfate (0.06-200 µM) 处理 72 h，使用 RT-PCR 检测病毒 RNA 水平。
结果：Leupeptin hemisulfate 可以抑制 Vero 细胞中 SARS-CoV-2 的 RNA 水平，EC50 值为 42.34  µM。[1]
方法：SARS-CoV-2 假病毒感染的 Huh7 细胞用 Leupeptin hemisulfate (0.1-100 µM) 处理 24 h，使用 luciferase activity assay 检测假病毒感染情况。
结果：Leupeptin hemisulfate 抑制 Vero 细胞中的假病毒感染，EC50 值为 39.29  µM。[2]

方法：为测定巨噬细胞自噬通量，将 Leupeptin hemisulfate (9-40 mg/kg in 0.5 mL PBS) 单次腹腔注射给 C57BL/6NCrl 小鼠。
结果：Leupeptin hemisulfate 治疗后 LC3b 的积累率在肝脏最高，在脾脏最低。LC3a、ATG8/LC3b 同源物和 LC3b 相互作用蛋白 p62 以与 LC3b 相似的动力学降解。[3]
方法：为检测寒冷是否激活自噬流量，将 Leupeptin hemisulfate (40 mg/kg) 单次腹腔注射给 C57B6 小鼠，1 h 后将小鼠在 4 ℃ 下冷暴露 1 h。
结果：冷暴露小鼠在棕色脂肪中的 LC3-II 通量增加了 >2 倍。[4]

Determination of BET Protein Binding Affinities to I-BET726: For determination of binding affinities to BET protein bromodomains, I-BET726 is titrated against truncates containing both BD1 and BD2 of BRD2 (10 nM), BRD3 (10 nM), and BRD4 (10 nM) in 50 mM HEPES pH7.5, 150 mM NaCl, 5% Glycerol, 1 mM DTT and 1 mM CHAPS in the presence of an Alexa 647 derivative (50 nM) of fluorescent ligand. After equilibrating for 1 h, the bromodomain protein: ligand interaction is detected using Time Resolved Fluorescence Resonance Energy Transfer (TR-FRET) following the addition of 1.5 nM europium chelate labeled anti-6His antibody. Plates are read using an Envision Plate reader (λEX = 337 nm, λEM = 615 nm, λEM = 665 nm; dual dichroic = 400 nm & 630 nm). These data are fitted to a four parameter IC50 model using Graphit data analysis software.