重组人精氨酸酶I（rhArg I）已成为治疗各种病理生理条件的潜在候选药物，范围从精氨酸缺乏性癌症、炎症病症到微生物感染。然而，rhArg I的循环半衰期较低，导致药代动力学和药效学性能不佳，迫切需要快速开发改进措施以克服这些限制。为了解决这个问题，制药公司正在开发聚乙二醇（PEG）化的rhArg I变体。然而，由于与PEG化蛋白的临床应用相关的限制，迫切需要开发一种安全（没有PEG化对应物的限制）且具有增加的循环半衰期的rhArg I变体。在本研究中，我们描述了一种融合人精氨酸酶I变体（FHA-3）的生成和特性化。FHA-3蛋白是通过将rhArg I与半衰期延长配体（人血清白蛋白结构域）通过肽连接子融合而成，并使用P. pastoris表达系统进行生产的。这种纯化的生物药物（FHA-3）在缓冲液中表现出（i）增强的精氨酸水解活性，（ii）无需辅因子，（iii）增加的循环半衰期（t1/2），以及（iv）在体外和体内条件下对人类癌细胞系具有强效的抗癌活性。©2023.作者，Springer Science+Business Media, LLC独家许可，Springer Nature的一部分。

Recombinant human arginase I (rhArg I) have emerged as a potential candidate for the treatment of varied pathophysiological conditions ranging from arginine-auxotrophic cancer, inflammatory conditions and microbial infection. However, rhArg I have a low circulatory half-life, leading to poor pharmacokinetic and pharmacodynamic properties, which necessitating the rapid development of modifications to circumvent these limitations. To address this, polyethylene glycol (PEG)ylated-rhArg I variants are being developed by pharmaceutical companies. However, because of the limitations associated with the clinical use of PEGylated proteins, there is a dire need in the art to develop rhArg I variant(s) which is safe (devoid of limitations of PEGylated counterpart) and possess increased circulatory half-life. In this study, we described the generation and characterization of a fused human arginase I variant (FHA-3) having improved circulatory half-life. FHA-3 protein was engineered by fusing rhArg I with a half-life extension partner (domain of human serum albumin) via a peptide linker and was produced using P. pastoris expression system. This purified biopharmaceutical (FHA-3) exhibits (i) increased arginine-hydrolyzing activity in buffer, (ii) cofactor - independency, (iii) increased circulatory half-life (t1/2) and (iv) potent anti-cancer activity against human cancer cell lines under in vitro and in vivo conditions.© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.