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Durrant MG, Fanton A, Tycko J, Hinks M, Chandrasekaran SS, Perry NT, Schaepe J, Du PP, Lotfy P, Bassik MC, Bintu L, Bhatt AS, Hsu PD. Systematic discovery of recombinases for efficient integration of large DNA sequences into the human genome. Nat Biotechnol 2023; 41:488-499. [PMID: 36217031 PMCID: PMC10083194 DOI: 10.1038/s41587-022-01494-w] [Citation(s) in RCA: 51] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 09/01/2022] [Indexed: 11/09/2022]
Abstract
Large serine recombinases (LSRs) are DNA integrases that facilitate the site-specific integration of mobile genetic elements into bacterial genomes. Only a few LSRs, such as Bxb1 and PhiC31, have been characterized to date, with limited efficiency as tools for DNA integration in human cells. In this study, we developed a computational approach to identify thousands of LSRs and their DNA attachment sites, expanding known LSR diversity by >100-fold and enabling the prediction of their insertion site specificities. We tested their recombination activity in human cells, classifying them as landing pad, genome-targeting or multi-targeting LSRs. Overall, we achieved up to seven-fold higher recombination than Bxb1 and genome integration efficiencies of 40-75% with cargo sizes over 7 kb. We also demonstrate virus-free, direct integration of plasmid or amplicon libraries for improved functional genomics applications. This systematic discovery of recombinases directly from microbial sequencing data provides a resource of over 60 LSRs experimentally characterized in human cells for large-payload genome insertion without exposed DNA double-stranded breaks.
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Affiliation(s)
- Matthew G Durrant
- Arc Institute, Palo Alto, CA, USA
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
| | - Alison Fanton
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, USA
- University of California, Berkeley-University of California, San Francisco Graduate Program in Bioengineering, Berkeley, CA, USA
| | - Josh Tycko
- Department of Genetics, Stanford University, Stanford, CA, USA
| | - Michaela Hinks
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Sita S Chandrasekaran
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, USA
- University of California, Berkeley-University of California, San Francisco Graduate Program in Bioengineering, Berkeley, CA, USA
| | - Nicholas T Perry
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, USA
- University of California, Berkeley-University of California, San Francisco Graduate Program in Bioengineering, Berkeley, CA, USA
| | - Julia Schaepe
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Peter P Du
- Department of Genetics, Stanford University, Stanford, CA, USA
- Cancer Biology Program, Stanford University, Stanford, CA, USA
| | - Peter Lotfy
- Laboratory of Molecular and Cell Biology, Salk Institute for Biological Studies, La Jolla, CA, USA
| | | | - Lacramioara Bintu
- Department of Bioengineering, Stanford University, Stanford, CA, USA.
| | - Ami S Bhatt
- Department of Genetics, Stanford University, Stanford, CA, USA.
- Department of Medicine (Hematology), Stanford University, Stanford, CA, USA.
| | - Patrick D Hsu
- Arc Institute, Palo Alto, CA, USA.
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, USA.
- Laboratory of Molecular and Cell Biology, Salk Institute for Biological Studies, La Jolla, CA, USA.
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA, USA.
- Center for Computational Biology, University of California, Berkeley, Berkeley, CA, USA.
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Human Umbilical Cord Lining-Derived Epithelial Cells: A Potential Source of Non-Native Epithelial Cells That Accelerate Healing in a Porcine Cutaneous Wound Model. Int J Mol Sci 2022; 23:ijms23168918. [PMID: 36012184 PMCID: PMC9408523 DOI: 10.3390/ijms23168918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/03/2022] [Accepted: 08/07/2022] [Indexed: 11/21/2022] Open
Abstract
Human umbilical cord lining epithelial cells [CLECs) are naïve in nature and can be ethically recovered from cords that are routinely discarded. The success of using oral mucosal epithelial cells for cornea defects hints at the feasibility of treating cutaneous wounds using non-native CLECs. Herein, we characterized CLECs using flow cytometry (FC) and skin organotypic cultures in direct comparison with skin keratinocytes (KCs). This was followed by wound healing study to compare the effects of CLEC application and the traditional use of human skin allografts (HSGs) in a porcine wound model. While CLECs were found to express all the epidermal cell markers probed, the major difference between CLECs and KCs lies in the level of expression (in FC analysis) as well as in the location of expression (of the epithelium in organotypic cultures) of some of the basal cell markers probed. On the pig wounds, CLEC application promoted accelerated healing with no adverse reaction compared to HSG use. Though CLECs, like HSGs, elicited high levels of local and systemic immune responses in the animals during the first week, these effects were tapered off more quickly in the CLEC-treated group. Overall, the in vivo porcine data point to the potential of CLECs as a non-native and safe source of cells to treat cutaneous wounds.
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Ata-Abadi NS, Forouzanfar M, Dormiani K, Varnosfaderani SR, Pirjamali L, Nasr-Esfahani MH, Hajidavaloo RM. Site-specific integration as an efficient method for production of recombinant human hyaluronidase PH20 in semi-adherent cells. Appl Microbiol Biotechnol 2022; 106:1459-1473. [PMID: 35107633 DOI: 10.1007/s00253-022-11794-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 01/15/2022] [Accepted: 01/19/2022] [Indexed: 11/02/2022]
Abstract
PH20 is a hyaluronidase enzyme that can hydrolyze the glycosidic bond in hyaluronic acid as the major proteoglycan found in extracellular matrices. In the present study, we constructed and characterized two donor plasmids, one of them with one and the second with two PH20 expression cassettes. The expression vectors were site specifically integrated into the genome of HEK293T cells using PhiC31 integrase system to develop HEK293T stable cell lines secreting His-tagged recombinant human PH20 (rhPH20) in the culture supernatant. The produced rhPH20 was quantified using ELISA and turbidimetric assay tests, and its catalytic activity was also assessed by treating the mouse cumulus-oocyte complexes. Our results showed that the secreted rhPH20 in the culture supernatant had the specific activity of 16,660 IU/mg and the recombinant enzyme was able to remove the cumulus cells from oocytes. The results also indicated that phiC31 enzyme inserted the PH20-expressing donor vectors into the specific pseudo attP sites including 10q21.2 and 20q11.22 in the genome of the target cells with different copy numbers. Taken together, our findings demonstrate that PhiC31 integrase system is able to be applied as a robust tool for efficient production and secretion of soluble and active rhPH20 by HEK293T cells as a semi-adherent human cell line. KEY POINTS: • Efficient production of human recombinant PH20 in a semi-adherent human cell line • Successful application of PhiC31 integrase system for generation of stable recombinant clones • Use of a human cell line for expression of a recombinant human protein due to complex and efficient post-translational modifications and protein folding.
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Affiliation(s)
- Nafiseh Sanei Ata-Abadi
- Department of Animal Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Mahboobeh Forouzanfar
- Department of Animal Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Kianoush Dormiani
- Department of Animal Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
| | - Shiva Rouhollahi Varnosfaderani
- Department of Animal Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Leila Pirjamali
- Department of Animal Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Mohammad Hossein Nasr-Esfahani
- Department of Animal Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Reza Moradi Hajidavaloo
- Department of Animal Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
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Human Umbilical Cord-Derived Mesenchymal Stem Cells Promote Corneal Epithelial Repair In Vitro. Cells 2021; 10:cells10051254. [PMID: 34069578 PMCID: PMC8160941 DOI: 10.3390/cells10051254] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/08/2021] [Accepted: 05/14/2021] [Indexed: 12/31/2022] Open
Abstract
Corneal injuries are among the leading causes of blindness and vision impairment. Trauma, infectious keratitis, thermal and chemical (acids and alkali burn) injuries may lead to irreversible corneal scarring, neovascularization, conjunctivalization, and limbal stem cell deficiency. Bilateral blindness constitutes 12% of total global blindness and corneal transplantation remains a stand-alone treatment modality for the majority of end-stage corneal diseases. However, global shortage of donor corneas, the potential risk of graft rejection, and severe side effects arising from long-term use of immunosuppressive medications, demands alternative therapeutic approaches. Umbilical cord-derived mesenchymal stem cells can be isolated in large numbers using a relatively less invasive procedure. However, their role in injury induced corneal repair is largely unexplored. Here, we isolated, cultured and characterized mesenchymal stem cells from human umbilical cord, and studied the expression of mesenchymal (CD73, CD90, CD105, and CD34), ocular surface and epithelial (PAX6, WNT7A, and CK-8/18) lineage markers through immunofluorescence. The cultured human limbal and corneal epithelial cells were used as controls. Scratch assay was used to study the corneal epithelial repair potential of umbilical cord-derived mesenchymal stem cells, in vitro. The in vitro cultured umbilical cord-derived mesenchymal stem cells were plastic adherent, showed trilineage differentiation and expressed: mesenchymal markers CD90, CD105, CD73; epithelial marker CK-8/18, and ocular lineage developmental markers PAX6 and WNT-7A. Our findings suggest that umbilical cord-derived mesenchymal stem cells promote repair of the injured corneal epithelium by stimulating the proliferation of corneal epithelial cells, in vitro. They may serve as a potential non-ocular source of stem cells for treating injury induced bilateral corneal diseases.
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Ngan ND, Chau HM, Dong PN, Cung LX, Thuy NT, Thang PT, Thai TV, Nga VT, Bac ND. Tissue-Cultured Human Cord Lining Epithelial Cells in Treatment of Persistent Corneal Epithelial Defect. Open Access Maced J Med Sci 2019; 7:4266-4271. [PMID: 32215075 PMCID: PMC7084029 DOI: 10.3889/oamjms.2019.372] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 11/20/2019] [Accepted: 11/21/2019] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND: Persistent corneal epithelial defect (PED) is a consequence of many ocular surface disorders. Although many therapies have been suggested, the treatment of this disease have faced a lot of difficulties up to now. The transplatation of cultivated amniotic epithelial cells sheets is the new promised method for PED. Cord lining epithelial cells (CLECs) are epithelial cells of amniotic membrane of umbilical cord, so these cultivated cells sheet may be good for treating PED AIM: To evaluate the efficacy of the transplantation of cultivated CLECs sheets in treatment of PED and analyze some influential factors of this therapy. METHODS: A prospective interventional case series with transplantation of tissue-cultured human CLECs in 37 PED eyes in Vietnam National Institute of Ophthalmology. RESULTS: Thirty four of 37 eyes were healed with the cells transplantation and 22 eyes of them healed within a week postoperatively. There were normal corneal scars and normal corneal epithelial cell (by impression cytology detection) on transplantation site in all 31 successful cases. The other successful eyes were done lamellar keratoplasty (respectively in 1 month, 3 months, 6 months and 27 months postoperatively) to investigate the histopathology of the CLECs transplant site. The histopathological images showed normal corneal scar and there was no appearance of CLECs in transplant site. CONCLUSION: tissue-cultured human CLECs transplantation is a quite safe and effective treatment for persistent corneal epithelial defect. The CLECs may help the epithelial healing at early stage but do not exist at transplant site for a long time.
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Affiliation(s)
- Nguyen Dinh Ngan
- Department of Ophthalmology, 103 Military Hospital, Hanoi, Vietnam.,Department of Ophthalmology, Vietnam Military Medical University, Hanoi, Vietnam
| | - Hoang Minh Chau
- Department of Cornea and External diseases, Vietnam National Institute of Ophthalmology, Hanoi, Vietnam.,Department of Ophthalmology, Hanoi Medical University, Department of Ophthalmology, National University of Singapore, Singapore
| | - Pham Ngoc Dong
- Department of Cornea and External diseases, Vietnam National Institute of Ophthalmology, Hanoi, Vietnam
| | - Le Xuan Cung
- Department of Cornea and External diseases, Vietnam National Institute of Ophthalmology, Hanoi, Vietnam
| | - Nguyen Thu Thuy
- Department of Cornea and External diseases, Vietnam National Institute of Ophthalmology, Hanoi, Vietnam
| | - Phan Toan Thang
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Than Van Thai
- NTT Hi-tech Institute, Nguyen Tat Thanh University, Ho Chi Minh City, Vietnam
| | - Vu Thi Nga
- Institute for Research and Development, Duy Tan University, 03 Quang Trung, Danang, Vietnam
| | - Nguyen Duy Bac
- Vietnam Military Medical University (VMMU), Hanoi, Vietnam
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Qu L, Wang L, Zhu X, Zhang Y, Ou Q, Ma A, Sheng F, Wei X, Dai Y, Li G, Xie S. Global mapping of binding sites for phic31 integrase in transgenic maden-darby bovine kidney cells using ChIP-seq. Hereditas 2019; 156:3. [PMID: 30675136 PMCID: PMC6332687 DOI: 10.1186/s41065-018-0079-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 12/25/2018] [Indexed: 11/22/2022] Open
Abstract
Background ΦC31 integrase, a site-specific recombinase, can efficiently target attB-bearing transgenes to endogenous pseudo attP sites within mammalian genomes. The sequence features of endogenous binding sites will help us to fully understand the site-specific recognition function by ΦC31 integrase. The present study was aimed to uncover the global map of ΦC31 integrase binding sites in bovine cells and analysis the features of these binding sites by comprehensive bioinformatics methods. Results In this study, we constructed a ChIP-seq method that can be used to uncover the global binding sites by phiC31 integrase. 6740 potential ΦC31 integrase binding sites were identified. A sequence motif was found that contains inverted repeats and has similarities to wild-type attP site. Using REPEATMASKER, we identified a total of 20,183 repeat-regions distributed in 50 repeat types for the 6740 binding sites. These sites enriched in “regulation of GTPase activity” of in the GO category of biological process and KEGG pathway of signal transmembrane transporter activity. Conclusion This study is the first time to uncover the global map of binding sites for ΦC31 integrase using ChIP-sequencing method and analysis the features of these binding sites. This method will help us to fully understand the mechanism of the site-specific integration function by phiC31 integrase and will potentially boost its genetic manipulations in both gene therapy and generation of transgenic animals. Electronic supplementary material The online version of this article (10.1186/s41065-018-0079-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lijuan Qu
- Department of Laboratory Medicine, Shanghai Eighth People's Hospital, Shanghai, 200040 China
| | - Lei Wang
- Department of Laboratory Medicine, Shanghai Eighth People's Hospital, Shanghai, 200040 China
| | - Xueyuan Zhu
- Department of Laboratory Medicine, Shanghai Eighth People's Hospital, Shanghai, 200040 China
| | - Yan Zhang
- Department of Laboratory Medicine, Shanghai Eighth People's Hospital, Shanghai, 200040 China
| | - Qiang Ou
- Department of Laboratory Medicine, Shanghai Eighth People's Hospital, Shanghai, 200040 China
| | - Aying Ma
- Department of Respiratory Medicine, Shanghai First People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 201620 China
| | - Fengying Sheng
- Department of Laboratory Medicine, Shanghai Eighth People's Hospital, Shanghai, 200040 China
| | - Xiaoqing Wei
- Department of Laboratory Medicine, Shanghai Eighth People's Hospital, Shanghai, 200040 China
| | - Yue Dai
- Department of Laboratory Medicine, Shanghai Eighth People's Hospital, Shanghai, 200040 China
| | - Guoting Li
- Lab of Reproductive Pharmacology, NHC Key Lab of Reproduction Regulation, Shanghai Institute of Planned Parenthood Research, Fudan University, Shanghai, 200032 China
| | - Shuwu Xie
- Lab of Reproductive Pharmacology, NHC Key Lab of Reproduction Regulation, Shanghai Institute of Planned Parenthood Research, Fudan University, Shanghai, 200032 China
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Fani Maleki A, Sekhavati MH. Application of phiC31 integrase system in stem cells biology and technology: a review. FRONTIERS IN LIFE SCIENCE 2018. [DOI: 10.1080/21553769.2018.1447516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Adham Fani Maleki
- Embryonic and Stem Cell Biology and Biotechnology Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Mohammad Hadi Sekhavati
- Department of Animal Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
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Sivalingam J, Kenanov D, Ng WH, Lee SS, Phan TT, Maurer-Stroh S, Kon OL. Integrated Multimodal Evaluation of Genotoxicity in ZFN-Modified Primary Human Cells. Methods Mol Biol 2018; 1867:141-164. [PMID: 30155821 DOI: 10.1007/978-1-4939-8799-3_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Iatrogenic adverse events in clinical trials of retroviral vector-mediated gene-corrected cells have prioritized the urgent need for more comprehensive and stringent assessment of potentially genotoxic off-target alterations and the biosafety of cells intended for therapeutic applications. Genome editing tools such as zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) and clustered regularly interspaced palindromic repeats (CRISPR)-Cas9 nuclease systems are being investigated as safer and efficient alternatives for site-directed genome modification. Using site-specific integration into the AAVS1 locus of primary human cells as an example, we present an integrated approach to multimodal investigation of off-target alterations and an evaluation of potential genotoxicity induced by ZFN-mediated integration of a therapeutic transgene.
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Affiliation(s)
- Jaichandran Sivalingam
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Republic of Singapore.
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore.
- Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore, Republic of Singapore.
| | - Dimitar Kenanov
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore, Republic of Singapore.
| | - Wai Har Ng
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Republic of Singapore
| | - Sze Sing Lee
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Republic of Singapore
| | - Toan Thang Phan
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore
- CellResearch Corporation, Singapore, Republic of Singapore
| | - Sebastian Maurer-Stroh
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore, Republic of Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Republic of Singapore
| | - Oi Lian Kon
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Republic of Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore
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Umbilical cord stem cells in the treatment of corneal disease. Surv Ophthalmol 2017; 62:803-815. [DOI: 10.1016/j.survophthal.2017.02.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 02/13/2017] [Indexed: 12/13/2022]
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Saleh R, Reza HM. Short review on human umbilical cord lining epithelial cells and their potential clinical applications. Stem Cell Res Ther 2017; 8:222. [PMID: 29017529 PMCID: PMC5634865 DOI: 10.1186/s13287-017-0679-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The human umbilical cord has been studied extensively in the past two decades. It is free of ethical dilemmas, non-tumorigenic, and less immunogenic and thus provides a significant advantage over other stem cell sources. The cord lining yields both mesenchymal and epithelial stem cells. The mesenchymal cells have been appraised at length by many researchers, which led to the current review focusing on the cord lining epithelial cells (CLECs). These cells have high proliferative capacity and their superior harvest and multiplication, using the revolutionary CellOptimaTM technology, makes them better candidates in comparison to contemporary adult stem cells. Following 30 replication cycles these cells have been observed to retain their stemness, with their phenotype and karyotype intact. However, their remarkable immunosuppressant properties, protecting self as well as co-transplanted allografts from rejection, are what truly define their transplantation potential. They have been successfully applied to many chronic conditions, using animal models, including type 1 diabetes, limbal stem cell deficiency, burn injuries, and wound healing, etc. with encouraging results. CONCLUSIONS This review first discusses some of the advantages afforded by CLECs over other stem cell lines and then delineates their potential use in various clinical applications. Clinical trials using CLECs are currently underway in the US in collaboration with CellResearch Corp. and their potential positive findings will help garner an FDA approval, likely leading to the eventual commercialization of this promising technology.
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Affiliation(s)
- Razwa Saleh
- Department of Pharmaceutical Sciences, North South University, Plot 15, Block B, Bashundhara, Dhaka, 1229, Bangladesh
| | - Hasan Mahmud Reza
- Department of Pharmaceutical Sciences, North South University, Plot 15, Block B, Bashundhara, Dhaka, 1229, Bangladesh.
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Lee N, Shin J, Park JH, Lee GM, Cho S, Cho BK. Targeted Gene Deletion Using DNA-Free RNA-Guided Cas9 Nuclease Accelerates Adaptation of CHO Cells to Suspension Culture. ACS Synth Biol 2016; 5:1211-1219. [PMID: 26854539 DOI: 10.1021/acssynbio.5b00249] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Chinese hamster ovary (CHO) cells are the preferred host for the production of a wide array of biopharmaceuticals. Thus, efficient and rational CHO cell line engineering methods have been in high demand to improve quality and productivity. Here, we provide a novel genome engineering platform for increasing desirable phenotypes of CHO cells based upon the integrative protocol of high-throughput RNA sequencing and DNA-free RNA-guided Cas9 (CRISPR associated protein9) nuclease-based genome editing. For commercial production of therapeutic proteins, CHO cells have been adapted for suspension culture in serum-free media, which is highly beneficial with respect to productivity and economics. To engineer CHO cells for rapid adaptation to a suspension culture, we exploited strand-specific RNA-seq to identify genes differentially expressed according to their adaptation trajectory in serum-free media. More than 180 million sequencing reads were generated and mapped to the currently available 109,152 scaffolds of the CHO-K1 genome. We identified significantly downregulated genes according to the adaptation trajectory and then verified their effects using the genome editing method. Growth-based screening and targeted amplicon sequencing revealed that the functional deletions of Igfbp4 and AqpI gene accelerate suspension adaptation of CHO-K1 cells. The availability of this strand-specific transcriptome sequencing and DNA-free RNA-guided Cas9 nuclease mediated genome editing facilitates the rational design of the CHO cell genome for efficient production of high quality therapeutic proteins.
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Affiliation(s)
- Namil Lee
- Department of Biological Sciences and KI for the BioCentury, KAIST , Daejeon 305-701, Republic of Korea
| | - JongOh Shin
- Department of Biological Sciences and KI for the BioCentury, KAIST , Daejeon 305-701, Republic of Korea
| | - Jin Hyoung Park
- Department of Biological Sciences and KI for the BioCentury, KAIST , Daejeon 305-701, Republic of Korea
| | - Gyun Min Lee
- Department of Biological Sciences and KI for the BioCentury, KAIST , Daejeon 305-701, Republic of Korea
| | - Suhyung Cho
- Department of Biological Sciences and KI for the BioCentury, KAIST , Daejeon 305-701, Republic of Korea
| | - Byung-Kwan Cho
- Department of Biological Sciences and KI for the BioCentury, KAIST , Daejeon 305-701, Republic of Korea
- Intelligent Synthetic Biology Center, Daejeon 305-701, Republic of Korea
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Sivalingam J, Kenanov D, Han H, Nirmal AJ, Ng WH, Lee SS, Masilamani J, Phan TT, Maurer-Stroh S, Kon OL. Multidimensional Genome-wide Analyses Show Accurate FVIII Integration by ZFN in Primary Human Cells. Mol Ther 2015; 24:607-19. [PMID: 26689265 PMCID: PMC4786920 DOI: 10.1038/mt.2015.223] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 12/10/2015] [Indexed: 12/19/2022] Open
Abstract
Costly coagulation factor VIII (FVIII) replacement therapy is a barrier to optimal clinical management of hemophilia A. Therapy using FVIII-secreting autologous primary cells is potentially efficacious and more affordable. Zinc finger nucleases (ZFN) mediate transgene integration into the AAVS1 locus but comprehensive evaluation of off-target genome effects is currently lacking. In light of serious adverse effects in clinical trials which employed genome-integrating viral vectors, this study evaluated potential genotoxicity of ZFN-mediated transgenesis using different techniques. We employed deep sequencing of predicted off-target sites, copy number analysis, whole-genome sequencing, and RNA-seq in primary human umbilical cord-lining epithelial cells (CLECs) with AAVS1 ZFN-mediated FVIII transgene integration. We combined molecular features to enhance the accuracy and activity of ZFN-mediated transgenesis. Our data showed a low frequency of ZFN-associated indels, no detectable off-target transgene integrations or chromosomal rearrangements. ZFN-modified CLECs had very few dysregulated transcripts and no evidence of activated oncogenic pathways. We also showed AAVS1 ZFN activity and durable FVIII transgene secretion in primary human dermal fibroblasts, bone marrow- and adipose tissue-derived stromal cells. Our study suggests that, with close attention to the molecular design of genome-modifying constructs, AAVS1 ZFN-mediated FVIII integration in several primary human cell types may be safe and efficacious.
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Affiliation(s)
- Jaichandran Sivalingam
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Republic of Singapore.,Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore.,Current address: Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore, Republic of Singapore
| | - Dimitar Kenanov
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore, Republic of Singapore
| | - Hao Han
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore, Republic of Singapore
| | - Ajit Johnson Nirmal
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Republic of Singapore
| | - Wai Har Ng
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Republic of Singapore
| | - Sze Sing Lee
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Republic of Singapore
| | | | - Toan Thang Phan
- CellResearch Corporation, Singapore, Republic of Singapore.,Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore
| | - Sebastian Maurer-Stroh
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore, Republic of Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Republic of Singapore
| | - Oi Lian Kon
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Republic of Singapore.,Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore
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Nafissi N, Foldvari M. Neuroprotective therapies in glaucoma: II. Genetic nanotechnology tools. Front Neurosci 2015; 9:355. [PMID: 26528114 PMCID: PMC4604245 DOI: 10.3389/fnins.2015.00355] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 09/17/2015] [Indexed: 01/01/2023] Open
Abstract
Neurotrophic factor genome engineering could have many potential applications not only in the deeper understanding of neurodegenerative disorders but also in improved therapeutics. The fields of nanomedicine, regenerative medicine, and gene/cell-based therapy have been revolutionized by the development of safer and efficient non-viral technologies for gene delivery and genome editing with modern techniques for insertion of the neurotrophic factors into clinically relevant cells for a more sustained pharmaceutical effect. It has been suggested that the long-term expression of neurotrophic factors is the ultimate approach to prevent and/or treat neurodegenerative disorders such as glaucoma in patients who do not respond to available treatments or are at the progressive stage of the disease. Recent preclinical research suggests that novel neuroprotective gene and cell therapeutics could be promising approaches for both non-invasive neuroprotection and regenerative functions in the eye. Several progenitor and retinal cell types have been investigated as potential candidates for glaucoma neurotrophin therapy either as targets for gene therapy, options for cell replacement therapy, or as vehicles for gene delivery. Therefore, in parallel with deeper understanding of the specific protective effects of different neurotrophic factors and the potential therapeutic cell candidates for glaucoma neuroprotection, the development of non-invasive and highly specific gene delivery methods with safe and effective technologies to modify cell candidates for life-long neuroprotection in the eye is essential before investing in this field.
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Affiliation(s)
| | - Marianna Foldvari
- School of Pharmacy and Waterloo Institute of Nanotechnology, University of WaterlooWaterloo, ON, Canada
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14
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Long-term and efficient expression of human β-globin gene in a hematopoietic cell line using a new site-specific integrating non-viral system. Gene Ther 2015; 22:663-74. [DOI: 10.1038/gt.2015.30] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 03/07/2015] [Accepted: 03/16/2015] [Indexed: 11/08/2022]
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15
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Lim IJ, Phan TT. Epithelial and Mesenchymal Stem Cells from the Umbilical Cord Lining Membrane. Cell Transplant 2014; 23:497-503. [DOI: 10.3727/096368914x678346] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Intense scientific research over the past two decades has yielded much knowledge about embryonic stem cells, mesenchymal stem cells from bone marrow, as well as epithelial stem cells from the skin and cornea. However, the billions of dollars spent in this research have not overcome the fundamental difficulties intrinsic to these stem cell strains related to ethics (embryonic stem cells), as well as to technical issues such as accessibility, ease of cell selection and cultivation, and expansion/mass production, while maintaining consistency of cell stemness (all of the stem cell strains already mentioned). Overcoming these technical hurdles has made stem cell technology expensive and any potential translational products unaffordable for most patients. Commercialization efforts have been rendered unfeasible by this high cost. Advanced biomedical research is on the rise in Asia, and new innovations have started to overcome these challenges. The Nobel Prize-winning Japanese development of iPSCs has effectively introduced a possible replacement for embryonic stem cells. For non-embryonic stem cells, cord lining stem cells (CLSCs) have overcome the preexisting difficulties inherent to mesenchymal stem cells from the bone marrow as well as epithelial stem cells from the skin and cornea, offering a realistic, practical, and affordable alternative for tissue repair and regeneration. This novel CLSC technology was developed in Singapore in 2004 and has 22 international patents granted to date, including those from the US and UK. CLSCs are derived from the umbilical cord outer lining membrane (usually regarded as medical waste) and is therefore free from ethical dilemmas related to its collection. The large quantity of umbilical cord lining membrane that can be collected translates to billions of stem cells that can be grown in primary stem cell culture and therefore very rapid and inexpensive cell cultivation and expansion for clinical translational therapies. Both mesenchymal and epithelial stem cells can be isolated from the umbilical cord lining membrane, usefully regenerating not only mesenchymal tissue, such as bone, cartilage, and cardiac and striated muscle, but also epithelial tissue, such as skin, cornea, and liver. Both mesenchymal and epithelial CLSCs are immune privileged and resist rejection. Clinically, CLSCs have proved effective in the treatment of difficult-to-heal human wounds, such as diabetic ulcers, recalcitrant chronic wounds, and even persistent epithelial defects of the cornea. Heart and liver regeneration has been shown to be successful in animal studies and await human trials. CLSCs have also been shown to be an effective feeder layer for cord blood hematopoietic stem cells and, more recently, has been recognized as an abundant and high-quality source of cells for iPSC production. Banking of CLSCs by cord blood banks in both private and public settings is now available in many countries, so that individuals may have their personal stores of CLSCs for future translational applications for both themselves and their families. Cord lining stem cells are strongly positioned to be the future of cell therapy and regenerative medicine.
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Affiliation(s)
- Ivor J. Lim
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore CellResearch Corporation Pte Ltd, Singapore
| | - Toan Thang Phan
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore CellResearch Corporation Pte Ltd, Singapore
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16
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Ma H, Ma Q, Lu Y, Wang J, Hu W, Gong Z, Cai L, Huang Y, Huang SZ, Zeng F. PhiC31 integrase induces efficient site-specific recombination in the Capra hircus genome. DNA Cell Biol 2014; 33:484-91. [PMID: 24754538 DOI: 10.1089/dna.2013.2124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Streptomyces phage φC31 integrase induces efficient site-specific recombination capable of integrating exogenous genes at pseudo attP sites in human, mouse, rat, rabbit, sheep, Drosophila, and bovine genomes. However, the φC31-mediated recombination between attB and the corresponding pseudo attP sites has not been investigated in Capra hircus. Here, we identified eight pseudo attP sites located in the intron or intergenic regions of the C. hircus genome, and demonstrated different levels of foreign gene expression after φC31 integrase-mediated integration. These pseudo attP sites share similar sequences with each other and with pseudo attP sites in other mammalian genomes, and these are associated with a neighboring consensus motif found in other genomes. The application of the φC31 integrase system in C. hircus provides a new option for genetic engineering of this economically important goat species.
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Affiliation(s)
- Haiyan Ma
- 1 Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiao Tong University , Shanghai, People's Republic of China
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17
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Intragenic integration in DLC1 sustains factor VIII expression in primary human cells without insertional oncogenicity. Gene Ther 2014; 21:402-12. [PMID: 24553346 PMCID: PMC3975812 DOI: 10.1038/gt.2014.11] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 12/20/2013] [Accepted: 01/09/2014] [Indexed: 02/04/2023]
Abstract
Techniques enabling precise genome modifications enhance the safety of gene-based therapy. DLC1 is a hot spot for phiC31 integrase-mediated transgene integration in vitro and in vivo. Here we show that integration of a coagulation factor VIII transgene into intron 7 of DLC1 supports durable expression of factor VIII in primary human umbilical cord-lining epithelial cells. Oligoclonal cells with factor VIII transgene integrated in DLC1 did not have altered expression of DLC1 or neighbouring genes within a 1-Mb interval. Only 1.9% of all expressed genes were transcriptionally altered; most were downregulated and mapped to cell cycle and DNA repair pathways. DLC1-integrated cells were not tumourigenic in vivo and were normal by high-resolution genomic DNA copy number analysis. Our data identify DLC1 as a locus for durable transgene expression that does not incur features of insertional oncogenesis, thus expanding options for developing ex vivo cell therapy mediated by site-specific integration methods.
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18
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Robert MA, Zeng Y, Raymond B, Desfossé L, Mairey E, Tremblay JP, Massie B, Gilbert R. Efficacy and site-specificity of adenoviral vector integration mediated by the phage φC31 integrase. Hum Gene Ther Methods 2013. [PMID: 23194172 DOI: 10.1089/hgtb.2012.122] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Adenoviral vectors deleted of all their viral genes (helper-dependent [HD]) are efficient gene-transfer vehicles. Because transgene expression is rapidly lost in actively dividing cells, we investigated the feasibility of using phage φC31 integrase (φC31-Int) to integrate an HD carrying an attB site and the puromycin resistance gene into human cells (HeLa) and murine myoblasts (C2C12) by co-infection with a second HD-expressing φC31-Int. Because the HD genome is linear, we also investigated whether its circularization, through expression of Cre using a third HD, affects integration. Efficacy and specificity were determined by scoring the number of puromycin-resistant colonies and by sequencing integration sites. Unexpectedly, circularization of HD was unnecessary and it even reduced the integration efficacy. The maximum integration efficacy achieved was 0.5% in HeLa cells and 0.1% in C2C12 myoblasts. Up to 76% of the integration events occurred at pseudo attP sites and previously characterized hotspots were found. A small (two- to three-fold) increase in the number of γ-H2AX positive foci, accompanied by no noticeable change in γ-H2AX expression, indicated the low genotoxicity of φC31-Int. In conclusion, integration of HD mediated by φC31-Int is an attractive alternative to engineer cells, because it permits site-specific integration of large DNA fragments with low genotoxicity.
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Affiliation(s)
- Marc-André Robert
- Biotechnology Research Institute, National Research Council Canada, Montréal, Canada, H4P 2R2
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19
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Lilyanna S, Martinez EC, Vu TD, Ling LH, Gan SU, Tan AL, Phan TT, Kofidis T. Cord lining-mesenchymal stem cells graft supplemented with an omental flap induces myocardial revascularization and ameliorates cardiac dysfunction in a rat model of chronic ischemic heart failure. Tissue Eng Part A 2013; 19:1303-15. [PMID: 23448654 DOI: 10.1089/ten.tea.2012.0407] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Myocardial restoration using tissue-engineered grafts to regenerate the ischemic myocardium offers improved donor cell retention, yet a limited cell survival resulting from poor vascularization needs to be addressed. A cell type derived from the subamnion, namely, cord-lining mesenchymal stem cells (CL-MSC), has recently been identified. Here we present a restorative strategy that combines a fibrin graft containing human CL-MSC and omental flap providing, thereby, cell-, structural-, and angiogenic support to the injured myocardium. The graft consisted of a mixture of 2×10(6) CL-MSC-GFP-Fluc and fibrin. Myocardial infarction (MI) was induced in nude rats and following confirmation of ensued heart failure with echocardiography 2 weeks after injury, therapeutic intervention was performed as follows: untreated (MI, n=7), CL-MSC graft (CL-MSCG, n=8), CL-MSCG and omental flap (CL-MSCG+OM, n=11), and omental flap (OM, n=8). In vivo bioluminescence imaging at 1, 3, 7, and 14 days post-treatment indicated comparable early donor cell viability between the CL-MSCG and CL-MSCG+OM. Treatment with CL-MSCG+OM improved the myocardial function as assessed by the measurement of end-diastolic left ventricular (LV) pressure (3.53±0.34 vs. 5.21±0.54 mmHg, p<0.05), contractility (+dP/dt, 3383.8±250.78 mmHg vs. 2464.9±191.8 mmHg, p<0.05), and the relaxation rate (-dP/dt, -2707.2±250.7 mmHg vs. 1948.7±207.8 mmHg, p<0.05), compared to MI control 6 weeks after ischemic injury. Furthermore, evidence of a 20.32% increase in the ejection fraction was observed in CL-MSCG+OM rats from week 2 to 6 after injury. Both CL-MSCG and CL-MSCG+OM led to an enhanced cardiac output (p<0.05), and attenuated the infarct size (35.7%±4.2% and 34.7%±4.8%), as compared to MI (60.7%±3.1%; p<0.01 and p<0.001, respectively). All treated groups had a higher arteriole density than controls. Yet, a higher amount of functional blood vessels, and a 20-fold increase in arteriole numbers were found in CL-MSCG+OM. Altogether, CL-MSCGs supplemented with vascular supply have the potential to repair the failing, chronically ischemic heart by improving myocardial revascularization, attenuating remodeling, and ameliorating cardiac dysfunction.
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Affiliation(s)
- Shera Lilyanna
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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20
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21
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Advanced therapies for the treatment of hemophilia: future perspectives. Orphanet J Rare Dis 2012; 7:97. [PMID: 23237078 PMCID: PMC3551751 DOI: 10.1186/1750-1172-7-97] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Accepted: 12/07/2012] [Indexed: 11/24/2022] Open
Abstract
Monogenic diseases are ideal candidates for treatment by the emerging advanced therapies, which are capable of correcting alterations in protein expression that result from genetic mutation. In hemophilia A and B such alterations affect the activity of coagulation factors VIII and IX, respectively, and are responsible for the development of the disease. Advanced therapies may involve the replacement of a deficient gene by a healthy gene so that it generates a certain functional, structural or transport protein (gene therapy); the incorporation of a full array of healthy genes and proteins through perfusion or transplantation of healthy cells (cell therapy); or tissue transplantation and formation of healthy organs (tissue engineering). For their part, induced pluripotent stem cells have recently been shown to also play a significant role in the fields of cell therapy and tissue engineering. Hemophilia is optimally suited for advanced therapies owing to the fact that, as a monogenic condition, it does not require very high expression levels of a coagulation factor to reach moderate disease status. As a result, significant progress has been possible with respect to these kinds of strategies, especially in the fields of gene therapy (by using viral and non-viral vectors) and cell therapy (by means of several types of target cells). Thus, although still considered a rare disorder, hemophilia is now recognized as a condition amenable to gene therapy, which can be administered in the form of lentiviral and adeno-associated vectors applied to adult stem cells, autologous fibroblasts, platelets and hematopoietic stem cells; by means of non-viral vectors; or through the repair of mutations by chimeric oligonucleotides. In hemophilia, cell therapy approaches have been based mainly on transplantation of healthy cells (adult stem cells or induced pluripotent cell-derived progenitor cells) in order to restore alterations in coagulation factor expression.
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22
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Qu L, Ma Q, Zhou Z, Ma H, Huang Y, Huang S, Zeng F, Zeng Y. A profile of native integration sites used by φC31 integrase in the bovine genome. J Genet Genomics 2012; 39:217-24. [PMID: 22624883 DOI: 10.1016/j.jgg.2012.03.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 03/07/2012] [Accepted: 03/30/2012] [Indexed: 11/24/2022]
Abstract
The Streptomyces phage φC31 integrase can efficiently target attB-bearing transgenes to endogenous pseudo attP sites within mammalian genomes. To better understand the activity of φC31 integrase in the bovine genome, DNA sequences of 44 integration events were analyzed, and 32 pseudo attP sites were identified. The majority of these sites share a sequence motif that contains inverted repeats and has similarities to wild-type attP site. Genomic DNA flanking these sites typically contained repetitive sequence elements, such as short and long interspersed repetitive elements. These sequence features indicate that DNA sequence recognition plays an important role in guiding φC31-mediated site-specific integration. In addition, BF27 integration hotspot sites were identified in the bovine genome, which accounted for 13.6% of all isolated integration events and mapped to an intron of the deleted in liver cancer 1 (DLC1) gene. Also we found that the pseudo attP sites in the bovine genome had other features in common with those in the human genome. This study represents the first time that the sequence features of pseudo attP sites in the bovine genome were analyzed. We conclude that this site-specific integrase system has great potential for applied modifications of the bovine genome.
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Affiliation(s)
- Lijuan Qu
- Shanghai Institute of Medical Genetics, Children's Hospital of Shanghai, Shanghai Jiao Tong University School of Medicine, 24/1400 West Beijing Road, Shanghai 200040, China
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23
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Umbilical cord lining stem cells as a novel and promising source for ocular surface regeneration. Stem Cell Rev Rep 2012; 7:935-47. [PMID: 21431286 DOI: 10.1007/s12015-011-9245-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The stem cells involved in renewal of the corneal epithelium are located in the basal region of the limbus, a narrow transition zone surrounding the cornea. In many ocular surface disorders loss of these stem cells results in partial or complete vision loss. Conventional corneal transplant in these patients is associated with dismal results. Stem cell transplantation offers new hope to such patients. The umbilical cord is emerging as an important source of stem cells that may have potential clinical applications. There are advantages to the use of umbilical cord stem cells as these cells are less immunogenic, non-tumorigenic, highly proliferative and ethically acceptable. In this study, we have confirmed the expression of several putative limbal stem cell markers such as HES1, ABCG2, BMI1, CK15 as well as cell adhesion-associated molecules INTEGRIN-α6, -α9, -β1, COLLAGEN-IV and LAMININ in our recently characterized CLEC-muc population derived from human umbilical cord. Ex vivo expansion of these cells on a human amniotic membrane substrate formed a stratified cell sheet that similarly expresses some of these molecules as well as cornea-specific cytokeratins, CK3 and CK12. Transplantation of a bioengineered CLEC-muc sheet in limbal stem cell-deficient rabbit eyes resulted in regeneration of a smooth, clear corneal surface with phenotypic expression of the normal corneal-specific epithelial markers CK3, CK12 but not CK4 or CK1/10. Our results suggest that CLEC-muc is a novel stem cell that can be ex vivo expanded for corneal epithelial regeneration in the treatment of various eye diseases.
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24
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Chavez CL, Keravala A, Chu JN, Farruggio AP, Cuéllar VE, Voorberg J, Calos MP. Long-term expression of human coagulation factor VIII in a tolerant mouse model using the φC31 integrase system. Hum Gene Ther 2012; 23:390-8. [PMID: 22077817 DOI: 10.1089/hum.2011.110] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We generated a mouse model for hemophilia A that combines a homozygous knockout for murine factor VIII (FVIII) and a homozygous addition of a mutant human FVIII (hFVIII). The resulting mouse, having no detectable FVIII protein or activity and tolerant to hFVIII, is useful for evaluating FVIII gene-therapy protocols. This model was used to develop an effective gene-therapy strategy using the φC31 integrase to mediate permanent genomic integration of an hFVIII cDNA deleted for the B-domain. Various plasmids encoding φC31 integrase and hFVIII were delivered to the livers of these mice by using hydrodynamic tail-vein injection. Long-term expression of therapeutic levels of hFVIII was observed over a 6-month time course when an intron was included in the hFVIII expression cassette and wild-type φC31 integrase was used. A second dose of the hFVIII and integrase plasmids resulted in higher long-term hFVIII levels, indicating that incremental doses were beneficial and that a second dose of φC31 integrase was tolerated. We observed a significant decrease in the bleeding time after a tail-clip challenge in mice treated with plasmids expressing hFVIII and φC31 integrase. Genomic integration of the hFVIII expression plasmid was demonstrated by junction PCR at a known hotspot for integration in mouse liver. The φC31 integrase system provided a nonviral method to achieve long-term FVIII gene therapy in a relevant mouse model of hemophilia A.
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Affiliation(s)
- Christopher L Chavez
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305-5120, USA
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25
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Karow M, Calos MP. The therapeutic potential of ΦC31 integrase as a gene therapy system. Expert Opin Biol Ther 2011; 11:1287-96. [PMID: 21736536 DOI: 10.1517/14712598.2011.601293] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
INTRODUCTION The φC31 integrase system is a phage-derived system that offers the ability to integrate plasmid DNA into the chromosomes at a subset of endogenous preferred locations associated with robust gene expression. Recent progress highlights the unique advantages of this system for in vivo gene therapy and for use in stem cells. AREAS COVERED The φC31 integrase system has been under development for ten years and has been demonstrated to be effective for integration of plasmids in a variety of tissues and organs for gene therapy in animal systems, as well as in isolated human cells. We focus on work with the φC31 integrase system during the past 12-18 months. This work has centered on a series of papers involving in vivo delivery of the integrase system to the liver and a variety of studies demonstrating the utility of the integrase system in stem cells. EXPERT OPINION We conclude that the φC31 integrase system has significant potential for liver gene therapy, if effective DNA delivery methods for large mammals become available. The φC31 integrase system displays an outstanding fit for use in pluripotent stem cells, and this area is expected to be the subject of intense development.
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Affiliation(s)
- Marisa Karow
- Stanford University School of Medicine, Department of Genetics, Stanford, CA 94305-5120, USA
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26
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Liras A. Induced human pluripotent stem cells and advanced therapies. Thromb Res 2011; 128:8-13. [DOI: 10.1016/j.thromres.2011.01.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 01/25/2011] [Accepted: 01/28/2011] [Indexed: 01/20/2023]
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Ma QW. [Progress of φC31 integrase system in site-specific integration]. YI CHUAN = HEREDITAS 2011; 33:567-75. [PMID: 21684861 DOI: 10.3724/sp.j.1005.2011.00567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Integrase of phage fC31 catalyses the homologous recombination between Streptomyces attachment site attB and the phage attachment site attP. Meanwhile, this integrase can mediate integration of attB-containing donor plasmids into the pseudo attP sites in eukaryotic genomes by a site-specific manner and resulting long-term and robust expression of integrated genes. Nowadays, fC31 integrase system is becoming a potential tool for genome modification, gene therapy and transgenic research. Recent progress of fC31 integrase system in integration mode in mammalian genomes, efficiency improvement and researches concerned on transgenic safety were summarized in this review.
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Affiliation(s)
- Qing-Wen Ma
- Children's Hospital of Shanghai, Institute of Medical Genetics, Shanghai JiaoTong University, Shanghai 200040, China.
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28
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Zhou Y, Gan SU, Lin G, Lim YT, Masilamani J, Mustafa FB, Phua ML, Rivino L, Phan TT, Lee KO, Calne R, MacAry PA. Characterization of human umbilical cord lining-derived epithelial cells and transplantation potential. Cell Transplant 2011; 20:1827-41. [PMID: 21439131 DOI: 10.3727/096368910x564085] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
In this study we describe the derivation and immunological characterization of a primary epithelial cell type from the human umbilical cord membrane. These cord lining epithelial cells (CLECs) expressed and/or secreted isoforms of the nonclassical human leukocyte antigen class I (HLA-1b) glycoproteins, HLA-G and E. Conditioned media from CLECs inhibited mitogen-stimulated T-lymphocyte responses, and in a mixed leukocyte reaction (MLR) assay, cocultured CLECs inhibited allogeneic responses with a concomitant reduction in proinflammatory cytokines. Using a transwell coculture system, it was demonstrated that these immunoregulatory effects were mediated by soluble factors secreted by CLECs, in a dose-dependent manner. Functional studies using HLA-G blocking antibody showed that the effects of CLEC-secreted products could be inhibited, thus demonstrating a significant and important role for soluble HLA-G. In vivo, we show that transplanted CLECs could be maintained for extended periods in immunocompetent mice where xenorejection rapidly destroyed primary keratinocytes, a control human epithelial cell type. Additionally, CLECs delayed the rejection of keratinocytes and extended their survival when cotransplanted, indicating an ability to protect adjacent human cell types that would otherwise be rejected if transplanted alone. We also show that CLECs transduced with a modified human proinsulin gene were transplanted intraperitoneally into streptozotocin (STZ)-induced diabetic mice, resulting in significantly lower levels of serum glucose compared to control mice. This study has characterized the immunological properties of CLECs and tested a potential therapeutic application in the treatment of a type 1 diabetes mouse model.
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Affiliation(s)
- Yue Zhou
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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29
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Kolacsek O, Krízsik V, Schamberger A, Erdei Z, Apáti A, Várady G, Mátés L, Izsvák Z, Ivics Z, Sarkadi B, Orbán TI. Reliable transgene-independent method for determining Sleeping Beauty transposon copy numbers. Mob DNA 2011; 2:5. [PMID: 21371313 PMCID: PMC3060107 DOI: 10.1186/1759-8753-2-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Accepted: 03/03/2011] [Indexed: 12/28/2022] Open
Abstract
Background The transposon-based gene delivery technique is emerging as a method of choice for gene therapy. The Sleeping Beauty (SB) system has become one of the most favored methods, because of its efficiency and its random integration profile. Copy-number determination of the delivered transgene is a crucial task, but a universal method for measuring this is lacking. In this paper, we show that a real-time quantitative PCR-based, transgene-independent (qPCR-TI) method is able to determine SB transposon copy numbers regardless of the genetic cargo. Results We designed a specific PCR assay to amplify the left inverted repeat-direct repeat region of SB, and used it together with the single-copy control gene RPPH1 and a reference genomic DNA of known copy number. The qPCR-TI method allowed rapid and accurate determination of SB transposon copy numbers in various cell types, including human embryonic stem cells. We also found that this sensitive, rapid, highly reproducible and non-radioactive method is just as accurate and reliable as the widely used blotting techniques or the transposon display method. Because the assay is specific for the inverted repeat region of the transposon, it could be used in any system where the SB transposon is the genetic vehicle. Conclusions We have developed a transgene-independent method to determine copy numbers of transgenes delivered by the SB transposon system. The technique is based on a quantitative real-time PCR detection method, offering a sensitive, non-radioactive, rapid and accurate approach, which has a potential to be used for gene therapy.
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Affiliation(s)
- Orsolya Kolacsek
- Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University and National Blood Center, Budapest, Hungary.
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30
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Chen CY, Wu HH, Chen CP, Chern SR, Hwang SM, Huang SF, Lo WH, Chen GY, Hu YC. Biosafety Assessment of Human Mesenchymal Stem Cells Engineered by Hybrid Baculovirus Vectors. Mol Pharm 2011; 8:1505-14. [DOI: 10.1021/mp100368d] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Chi-Yuan Chen
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan 300
| | - Hsiao-Hsuan Wu
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan 300
| | - Chih-Ping Chen
- Division of Genetics, Department of Obstetrics and Gynecology, MacKay Memorial Hospital, Taipei, Taiwan 104
| | - Schu-Rern Chern
- Division of Genetics, Department of Obstetrics and Gynecology, MacKay Memorial Hospital, Taipei, Taiwan 104
| | - Shiaw-Min Hwang
- Bioresource Collection and Research Center, Food Industry Research and Development Institute, Hsinchu, Taiwan 300
| | - Shiu-Feng Huang
- Division of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli, Taiwan 350
| | - Wen-Hsin Lo
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan 300
| | - Guan-Yu Chen
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan 300
| | - Yu-Chen Hu
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan 300
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Impact of hydrodynamic injection and phiC31 integrase on tumor latency in a mouse model of MYC-induced hepatocellular carcinoma. PLoS One 2010; 5:e11367. [PMID: 20614008 PMCID: PMC2894073 DOI: 10.1371/journal.pone.0011367] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Accepted: 06/08/2010] [Indexed: 01/04/2023] Open
Abstract
Background Hydrodynamic injection is an effective method for DNA delivery in mouse liver and is being translated to larger animals for possible clinical use. Similarly, ϕC31 integrase has proven effective in mediating long-term gene therapy in mice when delivered by hydrodynamic injection and is being considered for clinical gene therapy applications. However, chromosomal aberrations have been associated with ϕC31 integrase expression in tissue culture, leading to questions about safety. Methodology/Principal Findings To study whether hydrodynamic delivery alone, or in conjunction with delivery of ϕC31 integrase for long-term transgene expression, could facilitate tumor formation, we used a transgenic mouse model in which sustained induction of the human C-MYC oncogene in the liver was followed by hydrodynamic injection. Without injection, mice had a median tumor latency of 154 days. With hydrodynamic injection of saline alone, the median tumor latency was significantly reduced, to 105 days. The median tumor latency was similar, 106 days, when a luciferase donor plasmid and backbone plasmid without integrase were administered. In contrast, when active or inactive ϕC31 integrase and donor plasmid were supplied to the mouse liver, the median tumor latency was 153 days, similar to mice receiving no injection. Conclusions/Significance Our data suggest that ϕC31 integrase does not facilitate tumor formation in this C-MYC transgenic mouse model. However, in groups lacking ϕC31 integrase, hydrodynamic injection appeared to contribute to C-MYC-induced hepatocellular carcinoma in adult mice. Although it remains to be seen to what extent these findings may be extrapolated to catheter-mediated hydrodynamic delivery in larger species, they suggest that caution should be used during translation of hydrodynamic injection to clinical applications.
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