Extra-HEK293-AAV: Transcriptomics of modified HEK293 cell line for higher productivity of biologics (e.g. viral vectors, AAV)
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE248262 | GEO | 2023/11/25
REPOSITORIES: GEO
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Project description:Under intravenous delivery, recombinant adeno-associated vectors (rAAVs) interact with blood-borne components in ways that can critically alter their therapeutic efficiencies. We have previously shown that interaction with human galectin 3 binding protein dramatically reduces rAAV-6 efficacy, whereas binding of mouse C-reactive protein improves rAAV-1 and rAAV-6 transduction effectiveness. Herein we have assessed, through qualitative and quantitative studies, the proteins from mouse and human sera that bind with rAAV-8 and rAAV-9, two vectors that are being considered for clinical trials for patients with neuromuscular disorders. We show that, in contrast to rAAV-1 and rAAV-6, there was a substantial similarity in protein binding patterns between mouse and human sera for these vector serotypes. To establish an in vivo role for the vector binding of these sera proteins, we chose to study platelet factor 4 (PF4), which interacts with both vectors in both mouse and human sera. Experiments using PF4-knockout mice showed that a complete lack of PF4 did not alter skeletal muscle transduction for these vectors, whereas heart transduction was moderately improved. Our results strongly support our position that the impact of serum proteins on the transduction properties of rAAV-8 and rAAV-9, already observed in mouse models, should be similar in human preclinical trials.
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Project description:Exostosin 1 (Ext1) is a glycosyltransferase involved in the biosynthesis of the extracellular matrix Heparan Sulfate Proteoglycan (HSPG). Knockdown of Ext1 caused gastrulation defects and formation of an abnormal body axis. Since ext1 has been implicated as an indirect contributor to multiple signaling pathways in vertebrate development, microarray was used to identify genes expressed in gastrulae that would be affected by a reduction in ext1 expression. Microarray-based comparisons of gene expression in control vs. Ext1 MO embryos showed that Ext1 is involved in regulating genes that are related to metabolic process, development and signaling pathways. Half of the hits from the microarray are uncharacterized genes. Approximately forty-five percent of genes are related to metabolic process and thirty percent of genes are belonged to signaling and developmental process categories. Ten percent of each up-regulated and down-regulated gene set is predicted to function in establishment of localization by GO, which is consistent with EXT1 being involved in the movement of extracellular substances. The transcription factors or signaling protein, Isl1, Pitx2, TBX5A, Wnt5A, Wnt7A, WT1, Pax3, Wnt1, and Xbra were identified as Ext1 regulated genes. This analysis investigating the role of Ext1 during gastrulation and provide the information that EXT1 plays an important role in Xenopus early development. Exostosin 1 (EXT1) is a glycosyltransferase involved in the biosynthesis of the extracellular matrix Heparan Sulfate Proteoglycan (HSPG). Knockdown of EXT1 caused gastrulation defects and formation of an abnormal body axis. Since ext1 has been implicated as an indirect contributor to multiple signaling pathways in vertebrate development, microarray was used to identify genes expressed in gastrulae that would be affected by a reduction in ext1 expression. Microarray-based comparisons of gene expression in control vs. EXT1 MO embryos showed that EXT1 is involved in regulating genes that are related to metabolic process, development and signaling pathways. Half of the hits from the microarray are uncharacterized genes. Approximately forty-five percent of genes are related to metabolic process and thirty percent of genes are belonged to signaling and developmental process categories. Ten percent of each up-regulated and down-regulated gene set is predicted to function in establishment of localization by GO, which is consistent with EXT1 being involved in the movement of extracellular substances. The transcription factors or signaling protein, Isl1, Pitx2, TBX5A, Wnt5A, Wnt7A, WT1, Pax3, Wnt1, and Xbra were identified as EXT1 regulated genes. This analysis investigating the role of EXT1 during gastrulation and provide the information that EXT1 plays an important role in Xenopus early development.
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Project description:Gene therapy with adeno-associated virus (AAV)-based vectors shows great promise for the gene therapeutic treatment of a broad array of diseases. In fact, the treatment of genetic diseases with AAV vectors is currently the only in vivo gene therapy approach that is approved by the US Food and Drug Administration (FDA). Unfortunately, pre-existing antibodies against AAV severely limit the patient population that can potentially benefit from AAV gene therapy, especially if the vector is delivered by intravenous injection. Here, we demonstrate that we can selectively deplete anti-AAV antibodies by hemapheresis combined with AAV9 particles coupled to Sepharose beads. In rats that underwent hemapheresis and immunoadsorption, luciferase expression was dramatically increased in the hearts and fully restored in the livers of these rats. Importantly, our method can be readily adapted for the use in clinical AAV gene therapy.
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