23 results found
Hickmott JW, Prasertsuk P, Bell RV, et al., 2021, Towards Enhancing Signal Peptides for Respiratory Gene Therapy with Secreted Proteins, Publisher: CELL PRESS, Pages: 139-139, ISSN: 1525-0016
Korecki AJ, Cueva-Vargas JL, Fornes O, et al., 2021, Human MiniPromoters for ocular-rAAV expression in ON bipolar, cone, corneal, endothelial, Muller glial, and PAX6 cells, GENE THERAPY, ISSN: 0969-7128
Sinadinos A, Sergijenko A, Saleh A, et al., 2020, SINGLE-CELL ASSAYS FOR QUANTIFYING MRNA AND PROTEIN DURING CYSTIC FIBROSIS GENE THERAPY TRIALS, Publisher: WILEY, Pages: S203-S203, ISSN: 8755-6863
Mirjalili Mohanna SZ, Hickmott JW, Lam SL, et al., 2020, Germline CRISPR/Cas9-mediated gene editing prevents vision loss in a novel mousemodel of Aniridia., Molecular Therapy - Methods and Clinical Development, Vol: 17, Pages: 478-490, ISSN: 2329-0501
Aniridia is a rare eye disorder, which is caused by mutations in the paired box 6 (PAX6) gene and results in vision loss due to the lack of a long-term vision-saving therapy. One potential approach to treating aniridia is targeted CRISPR-based genome editing. To enable the Pax6 small eye (Sey) mouse model of aniridia, which carries the same mutation found in patients, for preclinical testing of CRISPR-based therapeutic approaches, we endogenously tagged the Sey allele, allowing for the differential detection of protein from each allele. We optimized a correction strategy in vitro then tested it in vivo in the germline of our new mouse to validate the causality of the Sey mutation. The genomic manipulations were analyzed by PCR, as well as by Sanger and next-generation sequencing. The mice were studied by slit lamp imaging, immunohistochemistry, and western blot analyses. We successfully achieved both in vitro and in vivo germline correction of the Sey mutation, with the former resulting in an average 34.8% ± 4.6% SD correction, and the latter in restoration of 3xFLAG-tagged PAX6 expression and normal eyes. Hence, in this study we have created a novel mouse model for aniridia, demonstrated that germline correction of the Sey mutation alone rescues the mutant phenotype, and developed an allele-distinguishing CRISPR-based strategy for aniridia.
Simpson EM, Hickmott JW, Lam SL, et al., 2020, Germline CRISPR/Cas9-Mediated Gene Editing Prevents Vision Loss in a Novel Mouse Model of Aniridia, 23rd Annual Meeting of the American-Society-for-Gene-and-Cell-Therapy, Publisher: CELL PRESS, Pages: 142-142, ISSN: 1525-0016
Korecki AJ, Vargas JLC, Fornes O, et al., 2020, MiniPromoters for rAAV Ophthalmic Gene Therapy: Novel PAX6 and Cone Promoters; Improved Muller Glia, Bipolar ON, and Brain Retinal Barrier Promoters; and Expanded Analysis of a Corneal Stroma Promoter, 23rd Annual Meeting of the American-Society-for-Gene-and-Cell-Therapy, Publisher: CELL PRESS, Pages: 145-145, ISSN: 1525-0016
Simpson EM, Wasserman WW, Hickmott J, et al., 2020, PAX6 MINIPROMOTERS, US20170209538A1
The present invention provides novel nucleic acid sequence compositions and methods relating to minimal human PAX6promoters. The invention is based in part on the Surprising discovery that certain minimal PAX6 promoter elements arecapable of expressing in specific cell types in cells eye.
Simpson EM, Korecki AJ, Lam SL, et al., 2019, Intrastromal Delivery of rAAV PAX6 Transiently Rescues Corneal Defects in a Mouse Model of Aniridia, Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology (ARVO), Publisher: ASSOC RESEARCH VISION OPHTHALMOLOGY INC, ISSN: 0146-0404
Korecki AJ, Hickmott JW, Lam SL, et al., 2019, Twenty-seven tamoxifen-inducible iCre-driver mouse strains for eye and brain, including seventeen carrying a new inducible-first constitutive-ready allele, GENETICS, Vol: 211, Pages: 1155-1177, ISSN: 0016-6731
To understand gene function, the cre/loxP conditional system is the most powerful available for temporal and spatial control of expression in mouse. However, the research community requires more cre recombinase expressing transgenic mouse strains (cre-drivers) that restrict expression to specific cell types. To address these problems, a high-throughput method for large-scale production that produces high-quality results is necessary. Further, endogenous promoters need to be chosen that drive cell type specific expression, or we need to further focus the expression by manipulating the promoter. Here we test the suitability of using knock-ins at the docking site 5′ of Hprt for rapid development of numerous cre-driver strains focused on expression in adulthood, using an improved cre tamoxifen inducible allele (icre/ERT2), and testing a novel inducible-first, constitutive-ready allele (icre/f3/ERT2/f3). In addition, we test two types of promoters either to capture an endogenous expression pattern (MaxiPromoters), or to restrict expression further using minimal promoter element(s) designed for expression in restricted cell types (MiniPromoters). We provide new cre-driver mouse strains with applicability for brain and eye research. In addition, we demonstrate the feasibility and applicability of using the locus 5′ of Hprt for the rapid generation of substantial numbers of cre-driver strains. We also provide a new inducible-first constitutive-ready allele to further speed cre-driver generation. Finally, all these strains are available to the research community through The Jackson Laboratory.
Hickmott JW, Gunawardane U, Jensen K, et al., 2019, Correction: Epistasis between Pax6Sey and genetic background reinforces the value of defined hybrid mouse models for therapeutic trials., Gene Ther
This Article was originally published under Nature Research's License to Publish, but has now been made available under a CC BY 4.0 license. The PDF and HTML versions of the Article have been modified accordingly.
Simpson EM, Korecki AJ, Fornes O, et al., 2018, New miniPromoter Ple345 (NEFL) drives strong and specific expression in retinal ganglion cells of mouse and primate retina., Human Gene Therapy, Vol: 30, Pages: 257-272, ISSN: 1043-0342
Retinal gene therapy is leading the neurological gene therapy field, with 32 ongoing clinical trials of recombinant adeno-associated virus (rAAV)-based therapies. Importantly, over 50% of those trials are using restricted promoters from human genes. Promoters that restrict expression have demonstrated increased efficacy and can limit the therapeutic to the target cells thereby reducing unwanted off-target effects. Retinal ganglion cells are a critical target in ocular gene therapy; they are involved in common diseases such as glaucoma, rare diseases such as Leber's hereditary optic neuropathy, and in revolutionary optogenetic treatments. Here, we used computational biology and mined the human genome for the best genes from which to develop a novel minimal promoter element(s) designed for expression in restricted cell types (MiniPromoter) to improve the safety and efficacy of retinal ganglion cell gene therapy. Gene selection included the use of the first available droplet-based single-cell RNA sequencing (Drop-seq) dataset, and promoter design was bioinformatically driven and informed by a wide range of genomics datasets. We tested seven promoter designs from four genes in rAAV for specificity and quantified expression strength in retinal ganglion cells in mouse, and then the single best in nonhuman primate retina. Thus, we developed a new human-DNA MiniPromoter, Ple345 (NEFL), which in combination with intravitreal delivery in rAAV9 showed specific and robust expression in the retinal ganglion cells of the nonhuman-primate rhesus macaque retina. In mouse, we also developed MiniPromoters expressing in retinal ganglion cells, the hippocampus of the brain, a pan neuronal pattern in the brain, and peripheral nerves. As single-cell transcriptomics such as Drop-seq become available for other cell types, many new opportunities for additional novel restricted MiniPromoters will present.
Hickmott JW, Gunawardane U, Jensen K, et al., 2018, Epistasis between Pax6Sey and genetic background reinforces the value of defined hybrid mouse models for therapeutic trials, Gene Therapy, Vol: 25, Pages: 524-537, ISSN: 0969-7128
The small eye (Sey) mouse is a model of PAX6-aniridia syndrome (aniridia). Aniridia, a congenital ocular disorder caused by heterozygous loss-of-function mutations in PAX6, needs new vision saving therapies. However, high phenotypic variability in Sey mice makes development of such therapies challenging. We hypothesize that genetic background is a major source of undesirable variability in Sey mice. Here we performed a systematic quantitative examination of anatomical, histological, and molecular phenotypes on the inbred C57BL/6J, hybrid B6129F1, and inbred 129S1/SvImJ backgrounds. The Sey allele significantly reduced eye weight, corneal thickness, PAX6 mRNA and protein levels, and elevated blood glucose levels. Surprisingly, Pax6Sey/Sey brains had significantly elevated Pax6 transcripts compared to Pax6+/+ embryos. Genetic background significantly influenced 12/24 measurements, with inbred strains introducing severe ocular and blood sugar phenotypes not observed in hybrid mice. Additionally, significant interactions (epistasis) between Pax6 genotype and genetic background were detected in measurements of eye weight, cornea epithelial thickness and cell count, retinal mRNA levels, and blood glucose levels. The number of epistatic interactions was reduced in hybrid mice. In conclusion, severe phenotypes in the unnatural inbred strains reinforce the value of more naturalistic F1 hybrid mice for the development of therapies for aniridia and other disorders.
Simpson EM, Korecki AJ, Mathelier A, et al., 2017, New and Smaller MiniPromoters for rAAV-Based Expression in the Brain and Eye, 20th Annual Meeting of the American-Society-of-Gene-and-Cell-Therapy (ASGCT), Publisher: CELL PRESS, Pages: 256-256, ISSN: 1525-0016
Hickmott JW, Farkas RA, Tam BM, et al., 2017, Towards Intrastromal rAAV PAX6 Gene Therapy for the Congenital Blindness Disorder Aniridia, 20th Annual Meeting of the American-Society-of-Gene-and-Cell-Therapy (ASGCT), Publisher: CELL PRESS, Pages: 109-109, ISSN: 1525-0016
Farkas RA, Fornes O, Hickmott JW, et al., 2017, Bioinformatics Design of rAAV-Compatible MiniPromoters for Cell Type-Restricted Expression, 20th Annual Meeting of the American-Society-of-Gene-and-Cell-Therapy (ASGCT), Publisher: CELL PRESS, Pages: 337-337, ISSN: 1525-0016
Hickmott JW, Tam BM, Korecki AJ, et al., 2016, Towards an rAAV PAX6-Gene Therapy for Aniridia, Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology (ARVO), Publisher: ASSOC RESEARCH VISION OPHTHALMOLOGY INC, ISSN: 0146-0404
Korecki AJ, Hickmott JW, Lam SL, et al., 2016, Twenty-seven Single-copy Site-specific Cre-Driver Mouse Strains for Advancing Eye and Brain Research, Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology (ARVO), Publisher: ASSOC RESEARCH VISION OPHTHALMOLOGY INC, ISSN: 0146-0404
Hickmott JW, Chen C-Y, Arenillas DJ, et al., 2016, PAX6 MiniPromoters drive restricted expression from rAAV in the adult mouse retina., Mol Ther Methods Clin Dev, Vol: 3, Pages: 16051-16051, ISSN: 2329-0501
Current gene therapies predominantly use small, strong, and readily available ubiquitous promoters. However, as the field matures, the availability of small, cell-specific promoters would be greatly beneficial. Here we design seven small promoters from the human paired box 6 (PAX6) gene and test them in the adult mouse retina using recombinant adeno-associated virus. We chose the retina due to previous successes in gene therapy for blindness, and the PAX6 gene since it is: well studied; known to be driven by discrete regulatory regions; expressed in therapeutically interesting retinal cell types; and mutated in the vision-loss disorder aniridia, which is in need of improved therapy. At the PAX6 locus, 31 regulatory regions were bioinformatically predicted, and nine regulatory regions were constructed into seven MiniPromoters. Driving Emerald GFP, these MiniPromoters were packaged into recombinant adeno-associated virus, and injected intravitreally into postnatal day 14 mice. Four MiniPromoters drove consistent retinal expression in the adult mouse, driving expression in combinations of cell-types that endogenously express Pax6: ganglion, amacrine, horizontal, and Müller glia. Two PAX6-MiniPromoters drive expression in three of the four cell types that express PAX6 in the adult mouse retina. Combined, they capture all four cell types, making them potential tools for research, and PAX6-gene therapy for aniridia.
de Leeuw CN, Korecki AJ, Berry GE, et al., 2016, rAAV-compatible MiniPromoters for restricted expression in the brain and eye, Molecular Brain, Vol: 9, Pages: 1-13, ISSN: 1756-6606
BackgroundSmall promoters that recapitulate endogenous gene expression patterns are important for basic, preclinical, and now clinical research. Recently, there has been a promising revival of gene therapy for diseases with unmet therapeutic needs. To date, most gene therapies have used viral-based ubiquitous promoters–however, promoters that restrict expression to target cells will minimize off-target side effects, broaden the palette of deliverable therapeutics, and thereby improve safety and efficacy. Here, we take steps towards filling the need for such promoters by developing a high-throughput pipeline that goes from genome-based bioinformatic design to rapid testing in vivo.MethodsFor much of this work, therapeutically interesting Pleiades MiniPromoters (MiniPs; ~4 kb human DNA regulatory elements), previously tested in knock-in mice, were “cut down” to ~2.5 kb and tested in recombinant adeno-associated virus (rAAV), the virus of choice for gene therapy of the central nervous system. To evaluate our methods, we generated 29 experimental rAAV2/9 viruses carrying 19 different MiniPs, which were injected intravenously into neonatal mice to allow broad unbiased distribution, and characterized in neural tissues by X-gal immunohistochemistry for icre, or immunofluorescent detection of GFP.ResultsThe data showed that 16 of the 19 (84 %) MiniPs recapitulated the expression pattern of their design source. This included expression of: Ple67 in brain raphe nuclei; Ple155 in Purkinje cells of the cerebellum, and retinal bipolar ON cells; Ple261 in endothelial cells of brain blood vessels; and Ple264 in retinal Müller glia.ConclusionsOverall, the methodology and MiniPs presented here represent important advances for basic and preclinical research, and may enable a paradigm shift in gene therapy.
Hickmott JW, 2015, Origin of MLH1, MSH2, MSH6 and PMS2 mutations can help inform long-term care strategies for patients with colorectal and endometrial cancer, CLINICAL GENETICS, Vol: 87, Pages: 534-535, ISSN: 0009-9163
Hickmott JW, Chen C-Y, Arenillas DJ, et al., 2015, Deep Informatics Utilized to Design MiniPromoters for Driving PAX6-Like Retinal Expression with AAV, 18th Annual Meeting of the American-Society-of-Gene-and-Cell-Therapy (ASGCT), Publisher: NATURE PUBLISHING GROUP, Pages: S238-S238, ISSN: 1525-0016
Hickmott J, 2015, DYRK1B variant linked to autosomal dominant metabolic syndrome, CLINICAL GENETICS, Vol: 87, Pages: 30-31, ISSN: 0009-9163
Grewal C, Hickmott J, Rentas S, et al., 2012, A conserved histone deacetylase with a role in the regulation of cytokinesis in Schizosaccharomyces pombe, Cell Division, Vol: 7, Pages: 1-14, ISSN: 1747-1028
BackgroundIn Schizosaccharomyces pombe the SET domain protein, Set3p - together with its interacting partners, Snt1p, and Hif2p - form a complex that aids in preventing cell division failure upon mild cytokinetic stress. Intriguingly, the human orthologs of these proteins (MLL5, NCOR2, and TBL1X) are also important for the faithful completion of cytokinesis in tissue culture cells. Since MLL5, NCOR2, and TBL1X form a complex with the histone deacetylase, HDAC3, we sought to determine if an orthologous counterpart played a regulatory role in fission yeast cytokinesis.ResultsIn this report we identify the hos2 gene as the fission yeast HDAC3 ortholog. We show that Hos2p physically interacts with Set3p, Snt1p, and Hif2p, and that hos2∆ mutants are indeed compromised in their ability to reliably complete cell division in the presence of mild cytokinetic stresses. Furthermore, we demonstrate that over-expression of hos2 causes severe morphological and cytokinetic defects. Lastly, through recombinase mediated cassette exchange, we show that expression of human HDAC3 complements the cytokinetic defects exhibited by hos2∆ cells.ConclusionsThese data support a model in which Hos2p functions as an essential component of the Set3p-Snt1p-Hif2p complex with respect to the regulation of cytokinesis. The ability of human HDAC3 to complement the cytokinesis defects associated with the deletion of the hos2 gene suggests that further analysis of this system could provide insight into the role of HDAC3 in both the regulation of cell division, as well as other biological processes influenced by HDAC3 deacetylation.
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