Department of Basic and Translational Science, Penn Dental Medicine, USA.
Scheie Eye Institute, University of Pennsylvania, USA.
Ocul Surf. 2021 Jan;19:313-321. doi: 10.1016/j.jtos.2020.11.001. Epub 2020 Nov 6.
Acyclovir is most commonly used for treating ocular Herpes Keratitis, a leading cause of infectious blindness. However, emerging resistance to Acyclovir resulting from mutations in the thymidine kinase gene of Herpes Simplex Virus -1 (HSV-1), has prompted the need for new therapeutics directed against a different viral protein. One novel target is the HSV-1 Processivity Factor which is essential for tethering HSV-1 Polymerase to the viral genome to enable long-chain DNA synthesis.
A series of peptides, based on the crystal structure of the C-terminus of HSV-1 Polymerase, were constructed with hydrocarbon staples to retain their alpha-helical conformation. The stapled peptides were tested for blocking both HSV-1 DNA synthesis and infection. The most effective peptide was further optimized by replacing its negative N-terminus with two hydrophobic valine residues. This di-valine stapled peptide was tested for inhibiting HSV-1 infection of human primary corneal epithelial cells.
The stapled peptides blocked HSV-1 DNA synthesis and HSV-1 infection. The unstapled control peptide had no inhibitory effects. Specificity of the stapled peptides was confirmed by their inabilities to block infection by an unrelated virus. Significantly, the optimized di-valine stapled peptide effectively blocked HSV-1 infection in human primary corneal epithelial cells with selectivity index of 11.6.
Hydrocarbon stapled peptides that simulate the α-helix from the C-terminus of HSV-1 DNA polymerase can specifically block DNA synthesis and infection of HSV-1 in human primary corneal epithelial cells. These stapled peptides provide a foundation for developing a topical therapeutic for treating human ocular Herpes Keratitis.
阿昔洛韦最常用于治疗单纯疱疹病毒性角膜炎，这是传染性失明的主要原因。然而，单纯疱疹病毒 1（HSV-1）胸苷激酶基因突变导致的阿昔洛韦耐药性的出现，促使人们需要针对不同病毒蛋白的新疗法。一种新的靶标是 HSV-1 延续因子，它对于将 HSV-1 聚合酶连接到病毒基因组上以实现长链 DNA 合成至关重要。
根据 HSV-1 聚合酶 C 末端的晶体结构，构建了一系列带有碳氢化合物 staples 的肽，以保留其α-螺旋构象。测试了 stapled 肽对阻断 HSV-1 DNA 合成和感染的作用。最有效的肽进一步通过用两个疏水性缬氨酸残基替换其负 N 端进行了优化。测试了这种双缬氨酸 stapled 肽对抑制人原代角膜上皮细胞中 HSV-1 感染的作用。
stapled 肽阻断了 HSV-1 DNA 合成和 HSV-1 感染。未 stapled 的对照肽没有抑制作用。 stapled 肽不能阻断不相关病毒的感染，证实了其特异性。重要的是，优化的双缬氨酸 stapled 肽有效地阻断了人原代角膜上皮细胞中 HSV-1 的感染，选择性指数为 11.6。
模拟 HSV-1 DNA 聚合酶 C 末端α-螺旋的碳氢 stapled 肽可以特异性地阻断 HSV-1 在人原代角膜上皮细胞中的 DNA 合成和感染。这些 stapled 肽为开发治疗人类眼部单纯疱疹角膜炎的局部治疗方法提供了基础。
