Institute of Chemical Sciences and Engineering, School of Basic Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland.
Biomolecular Screening Facility, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne CH-1015, Switzerland.
J Med Chem. 2022 Jul 28;65(14):9735-9749. doi: 10.1021/acs.jmedchem.2c00306. Epub 2022 Jun 2.
Kallikrein-related peptidases 5 (KLK5) and 7 (KLK7) are serine proteases with homeostatic functions in the epidermis that play a critical role in Netherton syndrome (NS), a rare yet life-threatening genetic disorder that currently lacks specific treatment. Previous research suggests that controlling KLKs could lead to the development of NS therapies, but existing synthetic inhibitors have limitations. Herein, we used phage display to screen libraries comprising more than 100 billion different cyclic peptides and found selective, high-affinity inhibitors of KLK5 ( = 2.2 ± 0.1 nM) and KLK7 ( = 16 ± 4 nM). By eliminating protease-prone sites and conjugating the inhibitors to an albumin-binding peptide, we enhanced the inhibitor stability and prolonged the elimination half-life to around 5 h in mice. In tissue sections taken from mice, a fluorescently labeled peptide was detected in the epidermis, suggesting that the inhibitors can reach the KLKs upon systemic delivery and should be suited to control deregulated protease activity in NS.
激肽释放酶相关肽酶 5（KLK5）和 7（KLK7）是表皮中具有内稳态功能的丝氨酸蛋白酶，在 Netherton 综合征（NS）中起着关键作用，NS 是一种罕见但危及生命的遗传疾病，目前缺乏特异性治疗方法。先前的研究表明，控制 KLKs 可能会导致 NS 治疗方法的发展，但现有的合成抑制剂存在局限性。在此，我们使用噬菌体展示技术筛选了由超过 1000 亿个不同环肽组成的文库，发现了 KLK5（ = 2.2 ± 0.1 nM）和 KLK7（ = 16 ± 4 nM）的选择性、高亲和力抑制剂。通过消除蛋白酶倾向的位点并将抑制剂与白蛋白结合肽偶联，我们增强了抑制剂的稳定性，并将其在小鼠中的消除半衰期延长至约 5 小时。在从小鼠中取出的组织切片中，在表皮中检测到荧光标记的肽，这表明抑制剂可以在全身给药时到达 KLKs，并且应该适合控制 NS 中失调的蛋白酶活性。
