PDF(Pubmed)
Abstract：
We describe the design, synthesis, and activity of a potent thiourea-bridged backbone cyclic peptidomimetic known as Clarstatin, comprising a 5-amino acid sequence (Q/D)1-(R/K)2-X3-X4-A5-(Gln/Asp)1-(Arg/Lys)2-AA3-AA4-Ala5-based on a motif called \"shared epitope (SE)\", specifically present in specific alleles of the HLA-DRB1 gene. This SE binds to a particular site within the proline reach domain (P-domain) of the cell surface-calreticulin (CS-CRT). CS-CRT is a multifunctional endoplasmic reticulum (ER) calcium-binding protein that is located on the cell surface of T cells and triggers innate immune signaling, leading to the development of inflammatory autoimmune diseases. The development of Clarstatin was based on the parent peptide W-G-D1-K2-S3-G4-A5- derived from the active region of the SE. Following the design based on the cycloscan method, the synthesis of Clarstatin was performed by the Fmoc solid phase peptide synthesis (SPPS) method, purified by HPLC to 96% homogeneity, and its structure was confirmed by LC-MS. Clarstatin reduced calcium levels in Jurkat lymphocyte cultures, ameliorated uveitis in vivo in the experimental autoimmune uveitis (EAU) mice model, and was safe upon acute toxicity evaluation. These findings identify Clarstatin as a promising lead compound for future drug development as a novel class of therapeutic agents in the therapy of uveitis.
摘要：
我们描述了设计，合成，和称为克拉他汀的有效硫脲桥接骨架环状肽模拟物的活性，包含基于称为“共享表位（SE）”的基序的5个氨基酸序列（Q/D）1-（R/K）2-X3-X4-A5-（Gln/Asp）1-（Arg/Lys）2-AA3-AA4-Ala5，特异性存在于HLA-DRB1基因的特定等位基因中。该SE与细胞表面钙网蛋白（CS-CRT）的脯氨酸到达域（P域）内的特定位点结合。CS-CRT是一种多功能的内质网（ER）钙结合蛋白，位于T细胞的细胞表面并触发先天免疫信号，导致炎症性自身免疫性疾病的发展。克拉他汀的开发基于衍生自SE活性区域的亲本肽W-G-D1-K2-S3-G4-A5。遵循基于cycloscan方法的设计，克拉他汀的合成是通过Fmoc固相肽合成（SPPS）方法进行的，通过HPLC纯化至96％均一性，LC-MS证实了其结构。克拉他汀降低了Jurkat淋巴细胞培养物中的钙水平，在实验性自身免疫性葡萄膜炎（EAU）小鼠模型中体内改善葡萄膜炎，经急性毒性评价是安全的。这些发现将克拉他汀确定为未来药物开发的有希望的先导化合物，作为治疗葡萄膜炎的新型治疗剂。
