Mannose receptor‐mediated delivery of moss‐made α‐galactosidase A efficiently corrects enzyme deficiency in Fabry mice

Abstract

Enzyme replacement therapy (ERT) is an effective treatment for several lysosomal storage disorders (LSDs). Intravenously infused enzymes are taken up by tissues through either the mannose 6-phosphate receptor (M6PR) or the mannose receptor (MR). It is generally believed that M6PR-mediated endocytosis is a key mechanism for ERT in treating LSDs that affect the non-macrophage cells of visceral organs. However, the therapeutic efficacy of MR-mediated delivery of mannose-terminated enzymes in these diseases has not been fully evaluated. We tested the effectiveness of a non-phosphorylated α-galactosidase A produced from moss (referred to as moss-aGal) in vitro and in a mouse model of Fabry disease. Endocytosis of moss-aGal was MR-dependent. Compared to agalsidase alfa, a phosphorylated form of α-galactosidase A, moss-aGal was more preferentially targeted to the kidney. Cellular localization of moss-aGal and agalsidase alfa in the heart and kidney was essentially identical. A single injection of moss-aGal led to clearance of accumulated substrate in the heart and kidney to an extent comparable to that achieved by agalsidase alfa. This study suggested that mannose-terminated enzymes may be sufficiently effective for some LSDs in which non-macrophage cells are affected, and that M6P residues may not always be a prerequisite for ERT as previously considered.Electronic supplementary materialThe online version of this article (doi:10.1007/s10545-015-9886-9) contains supplementary material, which is available to authorized users.

Non-conventional expression systems for the production of vaccine proteins and immunotherapeutic molecules

“…This system was shown to stably overexpress human a-galactosidase A, with the resultant molecule able to efficiently correct this enzyme deficiency in Fabry mice. 92 In contrast to the above-describe plant systems, there has been interest in highly efficient transient expression models based on Agrobacterium infiltration or similar systems. This new approach offers 2 majors advantages over traditional plant-based systems.…”

Molecular basis for globotriaosylceramide regulation and enzyme uptake in immortalized aortic endothelial cells from Fabry mice

“…The Vps10p domain is thought to bind ligands through proteinaceous interactions (Marcusson et al 1994). It is intriguing that sortilin mediates the uptake of agalsidase alfa but not moss-aGal, because the difference between these two enzymes is exclusively limited to their carbohydrate side chains (Shen et al 2015b). We hypothesize that the sugar chains on α-gal A have an impact on sortilin-α-gal A interactions, probably through the altered surface topography of the enzyme.…”

“…Uptake study was performed as previously described (Shen et al 2015b). In brief, FMEC2 was incubated with α-gal A preparations at final concentration of 5 or 10 μg/ml in the presence or absence of indicated inhibitors.…”

Human Alpha Galactosidases Transiently Produced in Nicotiana benthamiana Leaves: New Insights in Substrate Specificities with Relevance for Fabry Disease

“…A priori the production in another “plant” host might also be considered, for example stable expression in lettuce ( Lactuca sativa ), algae or moss, in order to conceivably enhance yields and to avoid the high levels of phenolic and toxic alkaloids present in Nicotiana plants that might affect the purification procedures (Hempel et al, 2011; Chen et al, 2013; Xu and Zhang, 2014; Reski et al, 2015). Furthermore, recombinant human α-GAL has earlier been successfully produced in cultured Nicotiana tabacum cells and in an engineered moss cell line, eliminating possible transgene flow that might occur while using whole plants as production platforms (Kizhner et al, 2014; Shen et al, 2016). …”