As a well-recognized expert in the field of induced pluripotent stem cell (iPSC) generation, Creative Biolabs offers advanced and comprehensive iPSC reprogramming services with mature virus-based factor delivery systems.
Induced pluripotent stem cell (iPS cell) has been frequently applied in a serial of fields including diseasing modelling, drug screening, autologous cell therapy and biochemistry research. iPSCs can be obtained through the reprogramming of differentiated adult somatic tissue by ectopic expression of a set of core pluripotency-related transcription factors (OCT4, SOX2, KLF4, and MYC, OSKM). Nowadays, various virus delivery systems have been developed to deliver OSKM transcription factors into human or mouse fibroblasts. Nowadays, including the common initial materials such as fibroblasts and PBMC, we can also offer iPSC reprogramming service for adipose-derived stem cells.
Fig.1 The iPSC model.
Lentiviral delivery vectors, generally derived from HIV, have been used to express various sets of reprogramming factors in somatic cells with higher cloning capacities (8-10 kb) and infection efficiency. Moreover, both dividing and non-dividing cells can be infected. However, the less repression in pluripotent stem cells makes the iPSC clones more complex to be identified. Another possible problem is the generation of potentially harmful viral particles during reprogramming. The expression of tumor suppressor genes will be disrupted when randomly distributed viral transgene insertions exist in the opening reading frames or the expression of oncogenes is altered because of insertion nearby. In this case, the excisable lentivirus has been developed to achieve the features of transgene-free and little scar on the genome.
Fig.2 Reprogramming of somatic cells into iPSCs by viral vectors.
Adenoviral vector is the integration-defective viral delivery based on adenoviruses, which belong to one kind of medium-sized virues with a double-stranded linear DNA genome. It has been reported that the transfer of adenoviral gene leads to iPSC cells reprogramming without persistent genetic alterations of the host cell nucleus. Compared with the retroviral vector and lentiviral vector, adenoviral vector is able to infect both dividing and non-dividing cells，while with less infection efficiency. In summary, the features of transgene-free, vector-free, and no genomic integration make the programming process pretty “safe”.
Based on the negative sense, F-deficient Sendai viral vectors have also been served as a possible viral delivery system for iPSC reprogramming. It was reported the F-deficient Sendai viral vectors have been successfully used for the reprogramming of human fibroblasts and terminally differentiated circulating T cells. During the programming process, F-deficient Sendai viral vectors allow highly-efficient foreign genetic material to transfer and replicate in the cytoplasm of infected cells with the form of negative-sense ssRNA. However, the potential challenge is that it would be difficult to isolate transgene-free clones even at high passage numbers.
Adeno-associated virus (AAV) is a small nonpathogenic parvovirus which contains a 4.7kb single-stranded linear genome. As a potent gene delivery vector for both dividing and non-dividing cells, it is possible to be used as an iPSC programming vector. Some studies have shown that the genomes of AAV primarily persisting in an extrachromosomal form residue in the nucleus. In this case, the AAV vectors would be able to express reprogramming factors in somatic cells without the host genome disturbance. Moreover, AAV also plays an important role in the engineering of human pluripotent stem cells.
With our well-established iPSC platform, experienced scientists in Creative Biolabs are at your service in fulfilling your technical request. We are confident in offering the best services for our customers with a significant reduction in costs and time in delivery. Creative Biolabs also provides other various services regarding iPSC development. Please feel free to contact us for more information and a detailed quote.
Our service involves the use of viral vectors for the delivery of reprogramming factors into the cells, allowing them to revert back to a pluripotent state. We primarily utilize retroviruses and lentiviruses for this purpose. These viruses have been specifically engineered to carry the reprogramming factors into the target cells without causing disease.
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| Viral Vector Delivery System |
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| Customized Protocol Design |
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| Quality Control and Validation |
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Our service is comprehensive and includes specialist consulting at every step of the process – from picking the appropriate method and specific cells to reprogram, through to the actual viral delivery of reprogramming factors, subsequent identification, and isolation of iPSC colonies. You may get the following benefits from our services.
By choosing us for your iPSC reprogramming services, you can rest assured of receiving top-quality cells, high rates of reprogramming efficiency, and the best customer service at every step of the process.
Below are the findings presented in the article related to iPSC reprogramming factors delivery by virus.
Kunitomi et al. develop an improved SeV vector system to generate naive human iPSCs from various somatic cells by changing the structure and combination of SeV vectors. This method allows rapid removal of the SeV vectors, resulting in transgene-free naive iPSCs with superior differentiation potential.
They compared the reprogramming efficiency of these modified vectors. It was found that SeV-KLF4/miR/TS12 vector showed significantly higher reprogramming efficiency and the modified SeV vectors can be removed efficiently after reprogramming to naive iPSCs.
Fig. 3 Number of naive human iPSC colonies generated from HDFs at day 14 and qPCR analysis of SeV genome expression in naive iPSCs derived from HDFs reprogrammed with SeV vectors.3
References
For Research Use Only. Not For Clinical Use.
