Key raw materials for cell therapy—viral vectors
1、Introduction
Gene transfection technology is a key link in cell therapy. It refers to delivering plasmid DNA containing target genes to cells and expressing them in cells. It has been widely used in gene structure and function analysis, gene expression and regulation, gene therapy and Transgenic animal research. According to different delivery systems, they can be divided into viral vectors and non-viral vectors. As a good tool for gene delivery, viral vectors have irreplaceable advantages, such as high transfection efficiency and little damage to cells by viral vector-mediated methods. Viral vectors commonly used in cell therapy mainly include retroviral vectors and lentiviral vectors. Non-viral methods include chemical transfection, biological methods and physical methods. In today's industrialization stage of cell therapy, viral vectors are still the common means of delivery.
2、RNA virus vector
There are currently two commonly used RNA virus vectors: gamma retroviral vector (RV) and lentivirus vector (LV). Both gammaretroviruses and lentiviruses belong to the family Retroviridae. This type of virus is well suited for gene delivery because a large portion of their genome can be replaced by a targeted transgene, and once they infect a host cell, their RNA genome is reverse transcribed into cDNA and then stably integrated into the host genomic DNA [1]. Lentiviral vectors are gene therapy vectors developed based on HIV-1 (human immunodeficiency virus type I). This vector can efficiently integrate foreign genes into the genome of dividing and non-dividing cells [2]. Due to its wide host range, long expression time, small immune response and high biological safety, it has become an ideal gene therapy vector. However, the production method and purification process of lentiviral vectors are relatively complex, which limits the production scale to a certain extent. enlarge. γretroviral vectors can carry large fragments of foreign genes, can construct stable toxin-producing cell lines through microgram-level plasmids, and have high transduction rates into target cells. They have absolute advantages in the industrialization of cell therapy products. However, both gamma retroviral vectors and lentiviral vectors may have the potential risk of random insertion. However, so far, in the application of cell therapy, there are no safety incidents with gamma retroviral vectors and lentiviral vectors. In order to avoid the above risks , scientists designed a self-inactivating γ-RV (SIN-γRV) vector, which has been proven to be absolutely safe in clinical trials, with no cases of poor integration or leukemia [3].
3、DNA virus vector
DNA virus vectors mainly include adenovirus (ADV) vectors, adeno-associated virus (AAV) vectors and herpes simplex virus V (HSV) vectors [4]. ADV is a non-enveloped double-stranded DNA virus whose vector does not integrate into the host cell genome and is the most commonly used vaccine vector. AAV is a single-stranded DNA parvovirus. AAV vector has the characteristics of wide tropism, low immunogenicity and easy production, which is beneficial to clinical application. It is also non-pathogenic and rarely integrates into the host chromosome, resulting in long-term expression of the transgene [5]. HSV is a coated double-stranded DNA virus that can cause latent infection of ganglia. The clinical application of HSV vector-based gene therapy has mainly focused on cancer treatment, mainly due to its inherent oncolytic ability.
4、Summary
Viral vectors use the molecular mechanism of viruses to transmit their genome into other cells for infection. Compared with non-viral vectors, they have the unique advantages of high transduction efficiency and the ability to stably transfect cells. Therefore, viral vectors are often used in basic research, cell and gene therapy, or vaccine development. Whether it is basic research, clinical trials or industrial scale-up, we need to select the most appropriate viral vector based on the research purpose.
Reference：
1. Watanabe N, McKenna M. Generation of CAR T-cells using γ-hiv-vector. Methods in cell biology 2022, 167: 171-183.doi.org/10.1016/bs.mcb.2021.06.014
2. Milone M, O'Doherty U. Clinical use of lentiviral vectors. Leukemia 2018, 32(7): 1529-1541.doi.org/10.1038/s41375-018-0106-0
3. Hacein-Bey-Abina S, Pai S, Gaspar H, Armant M, Berry C, Blanche S, et al. A modified gamma -retrovirus vector for X-linked severe combined immunodeficiency. The New England journal of medicine 2014, 371 (15) : 1407-1417.doi.org/10.1056/nejmoa1404588
4. Lundstrom K. Viral Vectors in Gene Therapy: Where Do We Stand in 2023? Viruses, 2023, 15 (3). Doi.org/10.3390/v15030698
5. Li C, Samulski R. Engineering adeno-associated virus vectors for gene therapy. Nature reviews Genetics 2020, 21(4): 255-272.doi.org/10.1038/s41576-019-0205-4
Disclaimer: Shenzhen Cell Valley is committed to the research of cell and gene therapy, in order to promote emerging technologies and let more people understand the new developments in biomedicine.The content of this article is for information exchange only. This platform remains neutral with respect to the content, statements, and opinion judgments in the article, and does not represent the position and opinions of Shenzhen Cell Valley.The relevant information in this article should not be used for diagnosis or treatment, and cannot replace professional medical advice. Our website will not assume any responsibility.The final interpretation of the above statement belongs to our company’s website. This statement will apply to articles shared on our website at all times. Thank you for your cooperation! Copyright statement: The copyright of the article belongs to Shenzhen Cell Valley. Individuals are welcome to forward it to friends, media or Any unauthorized reproduction by the organization to other platforms will be regarded as infringement.If you need to reprint, please contact email: contact@sz-cell.com
Gene transfection technology is a key link in cell therapy. It refers to delivering plasmid DNA containing target genes to cells and expressing them in cells. It has been widely used in gene structure and function analysis, gene expression and regulation, gene therapy and Transgenic animal research. According to different delivery systems, they can be divided into viral vectors and non-viral vectors. As a good tool for gene delivery, viral vectors have irreplaceable advantages, such as high transfection efficiency and little damage to cells by viral vector-mediated methods. Viral vectors commonly used in cell therapy mainly include retroviral vectors and lentiviral vectors. Non-viral methods include chemical transfection, biological methods and physical methods. In today's industrialization stage of cell therapy, viral vectors are still the common means of delivery.
2、RNA virus vector
There are currently two commonly used RNA virus vectors: gamma retroviral vector (RV) and lentivirus vector (LV). Both gammaretroviruses and lentiviruses belong to the family Retroviridae. This type of virus is well suited for gene delivery because a large portion of their genome can be replaced by a targeted transgene, and once they infect a host cell, their RNA genome is reverse transcribed into cDNA and then stably integrated into the host genomic DNA [1]. Lentiviral vectors are gene therapy vectors developed based on HIV-1 (human immunodeficiency virus type I). This vector can efficiently integrate foreign genes into the genome of dividing and non-dividing cells [2]. Due to its wide host range, long expression time, small immune response and high biological safety, it has become an ideal gene therapy vector. However, the production method and purification process of lentiviral vectors are relatively complex, which limits the production scale to a certain extent. enlarge. γretroviral vectors can carry large fragments of foreign genes, can construct stable toxin-producing cell lines through microgram-level plasmids, and have high transduction rates into target cells. They have absolute advantages in the industrialization of cell therapy products. However, both gamma retroviral vectors and lentiviral vectors may have the potential risk of random insertion. However, so far, in the application of cell therapy, there are no safety incidents with gamma retroviral vectors and lentiviral vectors. In order to avoid the above risks , scientists designed a self-inactivating γ-RV (SIN-γRV) vector, which has been proven to be absolutely safe in clinical trials, with no cases of poor integration or leukemia [3].
3、DNA virus vector
DNA virus vectors mainly include adenovirus (ADV) vectors, adeno-associated virus (AAV) vectors and herpes simplex virus V (HSV) vectors [4]. ADV is a non-enveloped double-stranded DNA virus whose vector does not integrate into the host cell genome and is the most commonly used vaccine vector. AAV is a single-stranded DNA parvovirus. AAV vector has the characteristics of wide tropism, low immunogenicity and easy production, which is beneficial to clinical application. It is also non-pathogenic and rarely integrates into the host chromosome, resulting in long-term expression of the transgene [5]. HSV is a coated double-stranded DNA virus that can cause latent infection of ganglia. The clinical application of HSV vector-based gene therapy has mainly focused on cancer treatment, mainly due to its inherent oncolytic ability.
4、Summary
Viral vectors use the molecular mechanism of viruses to transmit their genome into other cells for infection. Compared with non-viral vectors, they have the unique advantages of high transduction efficiency and the ability to stably transfect cells. Therefore, viral vectors are often used in basic research, cell and gene therapy, or vaccine development. Whether it is basic research, clinical trials or industrial scale-up, we need to select the most appropriate viral vector based on the research purpose.
Reference：
1. Watanabe N, McKenna M. Generation of CAR T-cells using γ-hiv-vector. Methods in cell biology 2022, 167: 171-183.doi.org/10.1016/bs.mcb.2021.06.014
2. Milone M, O'Doherty U. Clinical use of lentiviral vectors. Leukemia 2018, 32(7): 1529-1541.doi.org/10.1038/s41375-018-0106-0
3. Hacein-Bey-Abina S, Pai S, Gaspar H, Armant M, Berry C, Blanche S, et al. A modified gamma -retrovirus vector for X-linked severe combined immunodeficiency. The New England journal of medicine 2014, 371 (15) : 1407-1417.doi.org/10.1056/nejmoa1404588
4. Lundstrom K. Viral Vectors in Gene Therapy: Where Do We Stand in 2023? Viruses, 2023, 15 (3). Doi.org/10.3390/v15030698
5. Li C, Samulski R. Engineering adeno-associated virus vectors for gene therapy. Nature reviews Genetics 2020, 21(4): 255-272.doi.org/10.1038/s41576-019-0205-4
Disclaimer: Shenzhen Cell Valley is committed to the research of cell and gene therapy, in order to promote emerging technologies and let more people understand the new developments in biomedicine.The content of this article is for information exchange only. This platform remains neutral with respect to the content, statements, and opinion judgments in the article, and does not represent the position and opinions of Shenzhen Cell Valley.The relevant information in this article should not be used for diagnosis or treatment, and cannot replace professional medical advice. Our website will not assume any responsibility.The final interpretation of the above statement belongs to our company’s website. This statement will apply to articles shared on our website at all times. Thank you for your cooperation! Copyright statement: The copyright of the article belongs to Shenzhen Cell Valley. Individuals are welcome to forward it to friends, media or Any unauthorized reproduction by the organization to other platforms will be regarded as infringement.If you need to reprint, please contact email: contact@sz-cell.com
