Amicus Therapeutics, Cranbury, New Jersey 08512, USA.
Hum Mutat. 2011 Aug;32(8):965-77. doi: 10.1002/humu.21530. Epub 2011 Jul 12.
Fabry disease is caused by mutations in the gene (GLA) that encodes α-galactosidase A (α-Gal A). The iminosugar AT1001 (GR181413A, migalastat hydrochloride, 1-deoxygalactonojirimycin) is a pharmacological chaperone that selectively binds and stabilizes α-Gal A, increasing total cellular levels and activity for some mutant forms (defined as "responsive"). In this study, we developed a cell-based assay in cultured HEK-293 cells to identify mutant forms of α-Gal A that are responsive to AT1001. Concentration-dependent increases in α-Gal A activity in response to AT1001 were shown for 49 (60%) of 81 mutant forms. The responses of α-Gal A mutant forms were generally consistent with the responses observed in male Fabry patient-derived lymphoblasts. Importantly, the HEK-293 cell responses of 19 α-Gal A mutant forms to a clinically achievable concentration of AT1001 (10 µM) were generally consistent with observed increases in α-Gal A activity in peripheral blood mononuclear cells from male Fabry patients orally administered AT1001 during Phase 2 clinical studies. This indicates that the cell-based responses can identify mutant forms of α-Gal A that are likely to respond to AT1001 in vivo. Thus, the HEK-293 cell-based assay may be a useful aid in the identification of Fabry patients with AT1001-responsive mutant forms.
法布瑞病是由编码α-半乳糖苷酶 A（α-Gal A）的基因（GLA）突变引起的。 氨基糖昔类药物 AT1001（GR181413A，米加司他汀盐酸盐，1-脱氧半乳糖氮己昔）是一种药理学伴侣，它选择性地结合并稳定α-Gal A，增加某些突变形式（定义为“有反应性”）的总细胞水平和活性。 在这项研究中，我们在培养的 HEK-293 细胞中开发了一种基于细胞的测定法，以鉴定对 AT1001 有反应的 α-Gal A 突变体。 对于 81 种突变体中的 49 种（60％），显示出 AT1001 浓度依赖性地增加 α-Gal A 活性。 α-Gal A 突变体的反应通常与在男性法布瑞患者衍生的淋巴母细胞中观察到的反应一致。 重要的是，在临床可达到的 AT1001 浓度（10 μM）下，19 种 α-Gal A 突变体对 HEK-293 细胞的反应通常与在接受 AT1001 口服治疗的男性法布瑞患者的外周血单核细胞中观察到的α-Gal A 活性增加一致。 在 2 期临床试验中。 这表明基于细胞的反应可以鉴定出可能对体内 AT1001 有反应的α-Gal A 突变体。 因此，基于 HEK-293 细胞的测定法可能是鉴定具有 AT1001 反应性突变体的法布瑞病患者的有用辅助手段。
