Transfection

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Transfection is the process of deliberately introducing naked or purified nucleic acids into eukaryotic cells. [1] [2] It may also refer to other methods and cell types, although other terms are often preferred: "transformation" is typically used to describe non-viral DNA transfer in bacteria and non-animal eukaryotic cells, including plant cells. In animal cells, transfection is the preferred term as transformation is also used to refer to progression to a cancerous state (carcinogenesis) in these cells. Transduction is often used to describe virus-mediated gene transfer into eukaryotic cells. [2] [3]

Contents

The word transfection is a portmanteau of trans- and infection. Genetic material (such as supercoiled plasmid DNA or siRNA constructs), may be transfected. Transfection of animal cells typically involves opening transient pores or "holes" in the cell membrane to allow the uptake of material. Transfection can be carried out using calcium phosphate (i.e. tricalcium phosphate), by electroporation, by cell squeezing, or by mixing a cationic lipid with the material to produce liposomes that fuse with the cell membrane and deposit their cargo inside.

Transfection can result in unexpected morphologies and abnormalities in target cells.

Terminology

The meaning of the term has evolved. [4] The original meaning of transfection was "infection by transformation", i.e., introduction of genetic material, DNA or RNA, from a prokaryote-infecting virus or bacteriophage into cells, resulting in an infection. For work with bacterial and archaeal cells transfection retains its original meaning as a special case of transformation. Because the term transformation had another sense in animal cell biology (a genetic change allowing long-term propagation in culture, or acquisition of properties typical of cancer cells), the term transfection acquired, for animal cells, its present meaning of a change in cell properties caused by introduction of DNA.[ citation needed ]

Methods

There are various methods of introducing foreign DNA into a eukaryotic cell: some rely on physical treatment (electroporation, cell squeezing, nanoparticles, magnetofection); others rely on chemical materials or biological particles (viruses) that are used as carriers. There are many different methods of gene delivery developed for various types of cells and tissues, from bacterial to mammalian. Generally, the methods can be divided into three categories: physical, chemical, and biological. [5]

Physical methods include electroporation, microinjection, gene gun, impalefection, hydrostatic pressure, continuous infusion, and sonication. Chemicals include methods such as lipofection, which is a lipid-mediated DNA-transfection process utilizing liposome vectors. It can also include the use of polymeric gene carriers (polyplexes). [6] Biological transfection is typically mediated by viruses, utilizing the ability of a virus to inject its DNA inside a host cell. A gene that is intended for delivery is packaged into a replication-deficient viral particle. Viruses used to date include retrovirus, lentivirus, adenovirus, adeno-associated virus, and herpes simplex virus.[ citation needed ]

Physical methods

Electroporator with square wave and exponential decay waveforms for in vitro, in vivo, adherent cell and 96 well electroporation applications. Manufactured by BTX Harvard Apparatus, Holliston MA USA. Gemini X2 generator.jpg
Electroporator with square wave and exponential decay waveforms for in vitro, in vivo, adherent cell and 96 well electroporation applications. Manufactured by BTX Harvard Apparatus, Holliston MA USA.

Physical methods are the conceptually simplest, using some physical means to force the transfected material into the target cell's nucleus. The most widely used physical method is electroporation, where short electrical pulses disrupt the cell membrane, allowing the transfected nucleic acids to enter the cell. [5] Other physical methods use different means to poke holes in the cell membrane: Sonoporation uses high-intensity ultrasound (attributed mainly to the cavitation of gas bubbles interacting with nearby cell membranes), optical transfection uses a highly focused laser to form a ~1 µm diameter hole. [7]

Several methods use tools that force the nucleic acid into the cell, namely: microinjection of nucleic acid with a fine needle; [5] biolistic particle delivery, in which nucleic acid is attached to heavy metal particles (usually gold) and propelled into the cells at high speed; [8] and magnetofection, where nucleic acids are attached to magnetic iron oxide particles and driven into the target cells by magnets. [8]

Hydrodynamic delivery is a method used in mice and rats, in which nucleic acids can be delivered to the liver by injecting a relatively large volume in the blood in less than 10 seconds; nearly all of the DNA is expressed in the liver by this procedure. [9]

Chemical methods

Chemical-based transfection can be divided into several kinds: cyclodextrin, [10] polymers, [11] liposomes, or nanoparticles [12] (with or without chemical or viral functionalization. See below).

Viral methods

DNA can also be introduced into cells using viruses as a carrier. In such cases, the technique is called transduction, and the cells are said to be transduced. Adenoviral vectors can be useful for viral transfection methods because they can transfer genes into a wide variety of human cells and have high transfer rates. [2] Lentiviral vectors are also helpful due to their ability to transduce cells not currently undergoing mitosis.

Protoplast fusion is a technique in which transformed bacterial cells are treated with lysozyme in order to remove the cell wall. Following this, fusogenic agents (e.g., Sendai virus, PEG, electroporation) are used in order to fuse the protoplast carrying the gene of interest with the target recipient cell. A major disadvantage of this method is that bacterial components are non-specifically introduced into the target cell as well.

Stable and transient transfection

Stable and transient transfection differ in their long term effects on a cell; a stably transfected cell will continuously express transfected DNA and pass it on to daughter cells, while a transiently transfected cell will express transfected DNA for a short amount of time and not pass it on to daughter cells.

For some applications of transfection, it is sufficient if the transfected genetic material is only transiently expressed. Since the DNA introduced in the transfection process is usually not integrated into the nuclear genome, the foreign DNA will be diluted through mitosis or degraded. [5] Cell lines expressing the Epstein–Barr virus (EBV) nuclear antigen 1 (EBNA1) or the SV40 large-T antigen allow episomal amplification of plasmids containing the viral EBV (293E) or SV40 (293T) origins of replication, greatly reducing the rate of dilution. [25]

If it is desired that the transfected gene actually remain in the genome of the cell and its daughter cells, a stable transfection must occur. To accomplish this, a marker gene is co-transfected, which gives the cell some selectable advantage, such as resistance towards a certain toxin. Some (very few) of the transfected cells will, by chance, have integrated the foreign genetic material into their genome. If the toxin is then added to the cell culture, only those few cells with the marker gene integrated into their genomes will be able to proliferate, while other cells will die. After applying this selective stress (selection pressure) for some time, only the cells with a stable transfection remain and can be cultivated further. [26]

Common agents for selecting stable transfection are:

RNA transfection

RNA can also be transfected into cells to transiently express its coded protein, or to study RNA decay kinetics. RNA transfection is often used in primary cells that do not divide.

siRNAs can also be transfected to achieve RNA silencing (i.e. loss of RNA and protein from the targeted gene). This has become a major application in research to achieve "knock-down" of proteins of interests (e.g. Endothelin-1 [27] ) with potential applications in gene therapy. Limitation of the silencing approach are the toxicity of the transfection for cells and potential "off-target" effects on the expression of other genes/proteins.

RNA can be purified from cells after lysis or synthesized from free nucleotides either chemically, or enzymatically using an RNA polymerase to transcribe a DNA template. As with DNA, RNA can be delivered to cells by a variety of means including microinjection, electroporation, and lipid-mediated transfection. If the RNA encodes a protein, transfected cells may translate the RNA into the encoded protein. [28] If the RNA is a regulatory RNA (such as a miRNA), the RNA may cause other changes in the cell (such as RNAi-mediated knockdown).

Encapsulating the RNA molecule in lipid nanoparticles was a breakthrough for producing viable RNA vaccines, solving a number of key technical barriers in delivering the RNA molecule into the human cell. [29] [30]

RNA molecules shorter than about 25nt (nucleotides) largely evade detection by the innate immune system, which is triggered by longer RNA molecules. Most cells of the body express proteins of the innate immune system, and upon exposure to exogenous long RNA molecules, these proteins initiate signaling cascades that result in inflammation. This inflammation hypersensitizes the exposed cell and nearby cells to subsequent exposure. As a result, while a cell can be repeatedly transfected with short RNA with few non-specific effects, repeatedly transfecting cells with even a small amount of long RNA can cause cell death unless measures are taken to suppress or evade the innate immune system (see "Long-RNA transfection" below).

Short-RNA transfection is routinely used in biological research to knock down the expression of a protein of interest (using siRNA) or to express or block the activity of a miRNA (using short RNA that acts independently of the cell's RNAi machinery, and therefore is not referred to as siRNA). While DNA-based vectors (viruses, plasmids) that encode a short RNA molecule can also be used, short-RNA transfection does not risk modification of the cell's DNA, a characteristic that has led to the development of short RNA as a new class of macromolecular drugs. [31]

Long-RNA transfection is the process of deliberately introducing RNA molecules longer than about 25nt into living cells. A distinction is made between short- and long-RNA transfection because exogenous long RNA molecules elicit an innate immune response in cells that can cause a variety of nonspecific effects including translation block, cell-cycle arrest, and apoptosis.

Endogenous vs. exogenous long RNA

The innate immune system has evolved to protect against infection by detecting pathogen-associated molecular patterns (PAMPs), and triggering a complex set of responses collectively known as "inflammation". Many cells express specific pattern recognition receptors (PRRs) for exogenous RNA including toll-like receptor 3,7,8 (TLR3, TLR7, TLR8), [32] [33] [34] [35] the RNA helicase RIG1 (RARRES3), [36] protein kinase R (PKR, a.k.a. EIF2AK2), [37] [38] members of the oligoadenylate synthetase family of proteins (OAS1, OAS2, OAS3), and others. All of these proteins can specifically bind to exogenous RNA molecules and trigger an immune response. The specific chemical, structural or other characteristics of long RNA molecules that are required for recognition by PRRs remain largely unknown despite intense study. At any given time, a typical mammalian cell may contain several hundred thousand mRNA and other, regulatory long RNA molecules. How cells distinguish exogenous long RNA from the large amount of endogenous long RNA is an important open question in cell biology. Several reports suggest that phosphorylation of the 5'-end of a long RNA molecule can influence its immunogenicity, and specifically that 5'-triphosphate RNA, which can be produced during viral infection, is more immunogenic than 5'-diphosphate RNA, 5'-monophosphate RNA or RNA containing no 5' phosphate. [39] [40] [41] [42] [43] [44] However, in vitro-transcribed (ivT) long RNA containing a 7-methylguanosine cap (present in eukaryotic mRNA) is also highly immunogenic despite having no 5' phosphate, [45] suggesting that characteristics other than 5'-phosphorylation can influence the immunogenicity of an RNA molecule.

Eukaryotic mRNA contains chemically modified nucleotides such as N6-methyladenosine, 5-methylcytidine, and 2'-O-methylated nucleotides. Although only a very small number of these modified nucleotides are present in a typical mRNA molecule, they may help prevent mRNA from activating the innate immune system by disrupting secondary structure that would resemble double-stranded RNA (dsRNA), [46] [34] a type of RNA thought to be present in cells only during viral infection. The immunogenicity of long RNA has been used to study both innate and adaptive immunity.

Repeated long-RNA transfection

Inhibiting only three proteins, interferon-β, STAT2, and EIF2AK2 is sufficient to rescue human fibroblasts from the cell death caused by frequent transfection with long, protein-encoding RNA. [45] Inhibiting interferon signaling disrupts the positive-feedback loop that normally hypersensitizes cells exposed to exogenous long RNA. Researchers have recently used this technique to express reprogramming proteins in primary human fibroblasts. [47]

See also

Related Research Articles

<span class="mw-page-title-main">Retrovirus</span> Family of viruses

A retrovirus is a type of virus that inserts a DNA copy of its RNA genome into the DNA of a host cell that it invades, thus changing the genome of that cell. After invading a host cell's cytoplasm, the virus uses its own reverse transcriptase enzyme to produce DNA from its RNA genome, the reverse of the usual pattern, thus retro (backwards). The new DNA is then incorporated into the host cell genome by an integrase enzyme, at which point the retroviral DNA is referred to as a provirus. The host cell then treats the viral DNA as part of its own genome, transcribing and translating the viral genes along with the cell's own genes, producing the proteins required to assemble new copies of the virus. Many retroviruses cause serious diseases in humans, other mammals, and birds.

<span class="mw-page-title-main">Electroporation</span> Method in molecular biology to make pores in cell membranes

Electroporation, or electropermeabilization, is a technique in which an electrical field is applied to cells in order to increase the permeability of the cell membrane. This may allow chemicals, drugs, electrode arrays or DNA to be introduced into the cell.

<span class="mw-page-title-main">DNA vaccine</span> Vaccine containing DNA

A DNA vaccine is a type of vaccine that transfects a specific antigen-coding DNA sequence into the cells of an organism as a mechanism to induce an immune response.

<span class="mw-page-title-main">Small interfering RNA</span> Biomolecule

Small interfering RNA (siRNA), sometimes known as short interfering RNA or silencing RNA, is a class of double-stranded RNA at first non-coding RNA molecules, typically 20–24 base pairs in length, similar to miRNA, and operating within the RNA interference (RNAi) pathway. It interferes with the expression of specific genes with complementary nucleotide sequences by degrading mRNA after transcription, preventing translation. It was discovered in 1998, by Andrew Fire at Carnegie Institution for Science in Washington DC and Craig Mello at University of Massachusetts in Worcester.

A DNA construct is an artificially-designed segment of DNA borne on a vector that can be used to incorporate genetic material into a target tissue or cell. A DNA construct contains a DNA insert, called a transgene, delivered via a transformation vector which allows the insert sequence to be replicated and/or expressed in the target cell. This gene can be cloned from a naturally occurring gene, or synthetically constructed. The vector can be delivered using physical, chemical or viral methods. Typically, the vectors used in DNA constructs contain an origin of replication, a multiple cloning site, and a selectable marker. Certain vectors can carry additional regulatory elements based on the expression system involved.

Lentivirus is a genus of retroviruses that cause chronic and deadly diseases characterized by long incubation periods, in humans and other mammalian species. The genus includes the human immunodeficiency virus (HIV), which causes AIDS. Lentiviruses are distributed worldwide, and are known to be hosted in apes, cows, goats, horses, cats, and sheep as well as several other mammals.

<span class="mw-page-title-main">Cationic liposome</span>

Cationic liposomes are spherical structures that contain positively charged lipids. Cationic liposomes can vary in size between 40 nm and 500 nm, and they can either have one lipid bilayer (monolamellar) or multiple lipid bilayers (multilamellar). The positive charge of the phospholipids allows cationic liposomes to form complexes with negatively charged nucleic acids through ionic interactions. Upon interacting with nucleic acids, cationic liposomes form clusters of aggregated vesicles. These interactions allow cationic liposomes to condense and encapsulate various therapeutic and diagnostic agents in their aqueous compartment or in their lipid bilayer. These cationic liposome-nucleic acid complexes are also referred to as lipoplexes. Due to the overall positive charge of cationic liposomes, they interact with negatively charged cell membranes more readily than classic liposomes. This positive charge can also create some issues in vivo, such as binding to plasma proteins in the bloodstream, which leads to opsonization. These issues can be reduced by optimizing the physical and chemical properties of cationic liposomes through their lipid composition. Cationic liposomes are increasingly being researched for use as delivery vectors in gene therapy due to their capability to efficiently transfect cells. A common application for cationic liposomes is cancer drug delivery.

<span class="mw-page-title-main">Exogenous DNA</span> DNA originating from outside an organism

Exogenous DNA is DNA originating outside the organism of concern or study. Exogenous DNA can be found naturally in the form of partially degraded fragments left over from dead cells. These DNA fragments may then become integrated into the chromosomes of nearby bacterial cells to undergo mutagenesis. This process of altering bacteria is known as transformation. Bacteria may also undergo artificial transformation through chemical and biological processes. The introduction of exogenous DNA into eukaryotic cells is known as transfection. Exogenous DNA can also be artificially inserted into the genome, which revolutionized the process of genetic modification in animals. By microinjecting an artificial transgene into the nucleus of an animal embryo, the exogenous DNA is allowed to merge the cell's existing DNA to create a genetically modified, transgenic animal. The creation of transgenic animals also leads into the study of altering sperm cells with exogenous DNA.

<span class="mw-page-title-main">Gene delivery</span> Introduction of foreign genetic material into host cells

Gene delivery is the process of introducing foreign genetic material, such as DNA or RNA, into host cells. Gene delivery must reach the genome of the host cell to induce gene expression. Successful gene delivery requires the foreign gene delivery to remain stable within the host cell and can either integrate into the genome or replicate independently of it. This requires foreign DNA to be synthesized as part of a vector, which is designed to enter the desired host cell and deliver the transgene to that cell's genome. Vectors utilized as the method for gene delivery can be divided into two categories, recombinant viruses and synthetic vectors.

Lipofectamine or Lipofectamine 2000 is a common transfection reagent, produced and sold by Invitrogen, used in molecular and cellular biology. It is used to increase the transfection efficiency of RNA or plasmid DNA into in vitro cell cultures by lipofection. Lipofectamine contains lipid subunits that can form liposomes in an aqueous environment, which entrap the transfection payload, e.g. DNA plasmids.

Magnetofection is a transfection method that uses magnetic fields to concentrate particles containing vectors to target cells in the body. Magnetofection has been adapted to a variety of vectors, including nucleic acids, non-viral transfection systems, and viruses. This method offers advantages such as high transfection efficiency and biocompatibility which are balanced with limitations.

Nucleofection is an electroporation-based transfection method which enables transfer of nucleic acids such as DNA and RNA into cells by applying a specific voltage and reagents. Nucleofection, also referred to as nucleofector technology, was invented by the biotechnology company Amaxa. "Nucleofector" and "nucleofection" are trademarks owned by Lonza Cologne AG, part of the Lonza Group.

Magnet-assisted transfection is a transfection method which uses magnetic interactions to deliver DNA into target cells. Nucleic acids are associated with magnetic nanoparticles, and magnetic fields drive the nucleic acid-particle complexes into target cells, where the nucleic acids are released.

<span class="mw-page-title-main">Vectors in gene therapy</span>

Gene therapy utilizes the delivery of DNA into cells, which can be accomplished by several methods, summarized below. The two major classes of methods are those that use recombinant viruses and those that use naked DNA or DNA complexes.

<span class="mw-page-title-main">Genetic engineering techniques</span> Methods used to change the DNA of organisms

Genetic engineering techniques allow the modification of animal and plant genomes. Techniques have been devised to insert, delete, and modify DNA at multiple levels, ranging from a specific base pair in a specific gene to entire genes. There are a number of steps that are followed before a genetically modified organism (GMO) is created. Genetic engineers must first choose what gene they wish to insert, modify, or delete. The gene must then be isolated and incorporated, along with other genetic elements, into a suitable vector. This vector is then used to insert the gene into the host genome, creating a transgenic or edited organism.

Transient expression, more frequently referred to "transient gene expression", is the temporary expression of genes that are expressed for a short time after nucleic acid, most frequently plasmid DNA encoding an expression cassette, has been introduced into eukaryotic cells with a chemical delivery agent like calcium phosphate (CaPi) or polyethyleneimine (PEI). However, unlike "stable expression," the foreign DNA does not fuse with the host cell DNA, resulting in the inevitable loss of the vector after several cell replication cycles. The majority of transient gene expressions are done with cultivated animal cells. The technique is also used in plant cells; however, the transfer of nucleic acids into these cells requires different methods than those with animal cells. In both plants and animals, transient expression should result in a time-limited use of transferred nucleic acids, since any long-term expression would be called "stable expression."

mRNA vaccine Type of vaccine

An mRNAvaccine is a type of vaccine that uses a copy of a molecule called messenger RNA (mRNA) to produce an immune response. The vaccine delivers molecules of antigen-encoding mRNA into immune cells, which use the designed mRNA as a blueprint to build foreign protein that would normally be produced by a pathogen or by a cancer cell. These protein molecules stimulate an adaptive immune response that teaches the body to identify and destroy the corresponding pathogen or cancer cells. The mRNA is delivered by a co-formulation of the RNA encapsulated in lipid nanoparticles that protect the RNA strands and help their absorption into the cells.

RNA therapeutics are a new class of medications based on ribonucleic acid (RNA). Research has been working on clinical use since the 1990s, with significant success in cancer therapy in the early 2010s. In 2020 and 2021, mRNA vaccines have been developed globally for use in combating the coronavirus disease. The Pfizer–BioNTech COVID-19 vaccine was the first mRNA vaccine approved by a medicines regulator, followed by the Moderna COVID-19 vaccine, and others.

A genetic vaccine is a vaccine that contains nucleic acids such as DNA or RNA that lead to protein biosynthesis of antigens within a cell. Genetic vaccines thus include DNA vaccines, RNA vaccines and viral vector vaccines.

<span class="mw-page-title-main">Intracellular delivery</span> Scientific research area

Intracellular delivery is the process of introducing external materials into living cells. Materials that are delivered into cells include nucleic acids, proteins, peptides, impermeable small molecules, synthetic nanomaterials, organelles, and micron-scale tracers, devices and objects. Such molecules and materials can be used to investigate cellular behavior, engineer cell operations or correct a pathological function.

References

  1. Transfection at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
  2. 1 2 3 "Transfection". Protocols and Applications Guide. Promega. Archived from the original on 25 June 2014. Retrieved 25 October 2014.
  3. Transduction, Genetic at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
  4. "Transfection" at Dorland's Medical Dictionary
  5. 1 2 3 4 Kim TK, Eberwine JH (August 2010). "Mammalian cell transfection: the present and the future". Analytical and Bioanalytical Chemistry. 397 (8): 3173–8. doi:10.1007/s00216-010-3821-6. PMC   2911531 . PMID   20549496.
  6. Saul JM, Linnes MP, Ratner BD, Giachelli CM, Pun SH (November 2007). "Delivery of non-viral gene carriers from sphere-templated fibrin scaffolds for sustained transgene expression". Biomaterials. 28 (31): 4705–16. doi:10.1016/j.biomaterials.2007.07.026. PMID   17675152.
  7. Tsukakoshi M, Kurata S, Nomiya Y, et al. (1984). "A Novel Method of DNA Transfection by Laser Microbeam Cell Surgery". Applied Physics B: Photophysics and Laser Chemistry. 35 (3): 135–140. Bibcode:1984ApPhB..35..135T. doi:10.1007/BF00697702. S2CID   123250337.
  8. 1 2 Mehier-Humbert S, Guy RH (April 2005). "Physical methods for gene transfer: improving the kinetics of gene delivery into cells". Adv Drug Deliv Rev. 57 (5): 733–53. doi:10.1016/j.addr.2004.12.007. PMID   15757758.
  9. Suda T, Liu D (2015). "Hydrodynamic Delivery". Nonviral Vectors for Gene Therapy - Physical Methods and Medical Translation. Advances in Genetics. Vol. 89. pp. 89–111. doi:10.1016/bs.adgen.2014.10.002. ISBN   9780128022726. PMID   25620009.{{cite book}}: |journal= ignored (help)
  10. Menuel S, Fontanay S, Clarot I, Duval RE, Diez L, Marsura A (December 2008). "Synthesis and complexation ability of a novel bis- (guanidinium)-tetrakis-(beta-cyclodextrin) dendrimeric tetrapod as a potential gene delivery (DNA and siRNA) system. Study of cellular siRNA transfection". Bioconjugate Chemistry. 19 (12): 2357–62. doi:10.1021/bc800193p. PMID   19053312.
  11. Fischer D, von Harpe A, Kunath K, Petersen H, Li Y, Kissel T (2002). "Copolymers of ethylene imine and N-(2-hydroxyethyl)-ethylene imine as tools to study effects of polymer structure on physicochemical and biological properties of DNA complexes". Bioconjugate Chemistry. 13 (5): 1124–33. doi:10.1021/bc025550w. PMID   12236795.
  12. "Nanoparticle Based Transfection Reagents". Biology Transfection Research Resource. Transfection.ws. Archived from the original on 21 April 2013. Retrieved 30 September 2009.
  13. Graham FL, van der Eb AJ (April 1973). "A new technique for the assay of infectivity of human adenovirus 5 DNA". Virology. 52 (2): 456–67. doi:10.1016/0042-6822(73)90341-3. PMID   4705382.
  14. Bacchetti S, Graham FL (April 1977). "Transfer of the gene for thymidine kinase to thymidine kinase-deficient human cells by purified herpes simplex viral DNA". Proceedings of the National Academy of Sciences of the United States of America. 74 (4): 1590–4. Bibcode:1977PNAS...74.1590B. doi: 10.1073/pnas.74.4.1590 . PMC   430836 . PMID   193108.
  15. Kriegler M (1991). Transfer and Expression: A Laboratory Manual. W. H. Freeman. pp. 96–97. ISBN   978-0-7167-7004-6.
  16. Felgner PL, Gadek TR, Holm M, Roman R, Chan HW, Wenz M, Northrop JP, Ringold GM, Danielsen M (November 1987). "Lipofection: a highly efficient, lipid-mediated DNA-transfection procedure". Proceedings of the National Academy of Sciences of the United States of America. 84 (21): 7413–7. Bibcode:1987PNAS...84.7413F. doi: 10.1073/pnas.84.21.7413 . PMC   299306 . PMID   2823261.
  17. Felgner JH, Kumar R, Sridhar CN, Wheeler CJ, Tsai YJ, Border R, Ramsey P, Martin M, Felgner PL (January 1994). "Enhanced gene delivery and mechanism studies with a novel series of cationic lipid formulations". The Journal of Biological Chemistry. 269 (4): 2550–61. doi: 10.1016/S0021-9258(17)41980-6 . PMID   8300583.
  18. Pipes BL, Vasanwala FH, Tsang TC, Zhang T, Luo P, Harris DT (January 2005). "Brief heat shock increases stable integration of lipid-mediated DNA transfections". BioTechniques. 38 (1): 48–52. doi: 10.2144/05381bm05 . PMID   15679084.[ permanent dead link ]
  19. Jacobsen LB, Calvin SA, Colvin KE, Wright M (June 2004). "FuGENE 6 Transfection Reagent: the gentle power". Methods. Transfection of Mammalian Cells. 33 (2): 104–12. doi:10.1016/j.ymeth.2003.11.002. PMID   15121164.
  20. Hellgren I, Drvota V, Pieper R, Enoksson S, Blomberg P, Islam KB, Sylvén C (August 2000). "Highly efficient cell-mediated gene transfer using non-viral vectors and FuGene6: in vitro and in vivo studies". Cellular and Molecular Life Sciences. 57 (8–9): 1326–33. doi:10.1007/PL00000769. PMID   11028922. S2CID   27916034.
  21. Lakshmipathy U, Thyagarajan B (2011). Primary and Stem Cells: Gene Transfer Technologies and Applications (1st ed.). Wiley-Blackwell. ISBN   978-0-470-61074-9.
  22. Arnold AS, Laporte V, Dumont S, Appert-Collin A, Erbacher P, Coupin G, Levy R, Poindron P, Gies JP (February 2006). "Comparing reagents for efficient transfection of human primary myoblasts: FuGENE 6, Effectene and ExGen 500". Fundamental & Clinical Pharmacology. 20 (1): 81–9. doi:10.1111/j.1472-8206.2005.00344.x. PMID   16448398. S2CID   42585711.
  23. Sapra, Rachit; Verma, Ram P.; Maurya, Govind P.; Dhawan, Sameer; Babu, Jisha; Haridas, V. (13 November 2019). "Designer Peptide and Protein Dendrimers: A Cross-Sectional Analysis". Chemical Reviews. 119 (21): 11391–11441. doi:10.1021/acs.chemrev.9b00153. ISSN   0009-2665. PMID   31556597. S2CID   203435702.
  24. Heitz, Marc; Javor, Sacha; Darbre, Tamis; Reymond, Jean-Louis (21 August 2019). "Stereoselective pH Responsive Peptide Dendrimers for siRNA Transfection". Bioconjugate Chemistry. 30 (8): 2165–2182. doi:10.1021/acs.bioconjchem.9b00403. ISSN   1043-1802. PMID   31398014. S2CID   199519310.
  25. Durocher Y, Perret S, Kamen A (January 2002). "High-level and high-throughput recombinant protein production by transient transfection of suspension-growing human 293-EBNA1 cells". Nucleic Acids Research. 30 (2): 9e–9. doi:10.1093/nar/30.2.e9. PMC   99848 . PMID   11788735.
  26. Fanelli A (2016). "The Science of Stable Cell Line Generation" . Retrieved 23 December 2017.
  27. Mawji IA, Marsden PA (June 2006). "RNA transfection is a versatile tool to investigate endothelin-1 posttranscriptional regulation". Experimental Biology and Medicine. 231 (6): 704–708. doi:10.3181/00379727-231-2310704 (inactive 31 January 2024). PMID   16740984.{{cite journal}}: CS1 maint: DOI inactive as of January 2024 (link)
  28. Herb M, Farid A, Gluschko A, Krönke M, Schramm M (November 2019). "Highly Efficient Transfection of Primary Macrophages with In Vitro Transcribed mRNA". Journal of Visualized Experiments (153). doi: 10.3791/60143 . PMID   31762462.
  29. Cooney, Elizabeth (1 December 2020). "How nanotechnology helps mRNA Covid-19 vaccines work". Stat . Retrieved 3 December 2020.
  30. Foley, Katherine Ellen (22 December 2020). "The first Covid-19 vaccines have changed biotech forever". Quartz. Quartz Media. Retrieved 11 January 2021.
  31. Tansey B (11 August 2006). "Macular degeneration treatment interferes with RNA messages". San Francisco Chronicle.
  32. Alexopoulou L, Holt AC, Medzhitov R, Flavell RA (2001). "Recognition of double-stranded RNA and activation of NF-kappaB by Toll-like receptor 3". Nature. 413 (6857): 732–738. Bibcode:2001Natur.413..732A. doi:10.1038/35099560. PMID   11607032. S2CID   4346537.
  33. Kariko K, Ni H, Capodici J, Lamphier M, Weissman D (2004). "mRNA is an endogenous ligand for Toll-like receptor 3". J Biol Chem. 279 (13): 12542–12550. doi: 10.1074/jbc.M310175200 . PMID   14729660.
  34. 1 2 Kariko K, Buckstein M, Ni H, Weissman D (2005). "Suppression of RNA recognition by Toll-like receptors: the impact of nucleoside modification and the evolutionary origin of RNA". Immunity. 23 (2): 165–175. doi: 10.1016/j.immuni.2005.06.008 . PMID   16111635.
  35. Diebold SS, Kaisho T, Hemmi H, Akira S, Reis e Sousa C (2004). "Innate antiviral responses by means of TLR7-mediated recognition of single-stranded RNA". Science. 303 (5663): 1529–1531. Bibcode:2004Sci...303.1529D. doi: 10.1126/science.1093616 . PMID   14976261. S2CID   33144196.
  36. Yoneyama M, Kikuchi M, Natsukawa T, Shinobu N, Imaizumi T, et al. (2004). "The RNA helicase RIG-I has an essential function in double-stranded RNA-induced innate antiviral responses". Nat Immunol. 5 (7): 730–737. doi:10.1038/ni1087. PMID   15208624. S2CID   34876422.
  37. Das HK, Das A, Ghosh-Dastidar P, Ralston RO, Yaghmai B, et al. (1981). "Protein synthesis in rabbit reticulocytes. Purification and characterization of a double-stranded RNA-dependent protein synthesis inhibitor from reticulocyte lysates". J Biol Chem. 256 (12): 6491–6495. doi: 10.1016/S0021-9258(19)69192-1 . PMID   7240221.
  38. Levin DH, Petryshyn R, London IM (1981). "Characterization of purified double-stranded RNA-activated eIF-2 alpha kinase from rabbit reticulocytes". J Biol Chem. 256 (14): 7638–7641. doi: 10.1016/S0021-9258(19)69008-3 . PMID   6265457.
  39. Hornung V, Ellegast J, Kim S, Brzozka K, Jung A, et al. (2006). "5'-triphosphate RNA is the ligand for RIG-I". Science. 314 (5801): 994–997. Bibcode:2006Sci...314..964H. doi: 10.1126/science.1132505 . PMID   17038590. S2CID   22436759.
  40. Saito T; Owen DM; Jiang F; Marcotrigiano J; Gale M, Jr. (2008). "Innate immunity induced by composition-dependent RIG-I recognition of Hepatitis C virus RNA". Nature. 454 (7203): 523–527. Bibcode:2008Natur.454..523S. doi:10.1038/nature07106. PMC   2856441 . PMID   18548002.
  41. Takahasi K, Yoneyama M, Nishihori T, Hirai R, Kumeta H, et al. (2008). "Nonself RNA-sensing mechanism of RIG-I helicase and activation of antiviral immune responses". Mol Cell. 29 (4): 428–440. doi: 10.1016/j.molcel.2007.11.028 . PMID   18242112.
  42. Yoneyama M, Fujita T (2008). "Structural mechanism of RNA recognition by the RIG-I-like receptors". Immunity. 29 (2): 178–181. doi: 10.1016/j.immuni.2008.07.009 . PMID   18701081.
  43. Schmidt A, Schwerd T, Hamm W, Hellmuth JC, Cui S, et al. (2009). "5'-triphosphate RNA requires base-paired structures to activate antiviral signaling via RIG-I". Proc Natl Acad Sci USA. 106 (29): 12067–12072. Bibcode:2009PNAS..10612067S. doi: 10.1073/pnas.0900971106 . PMC   2705279 . PMID   19574455.
  44. Schlee M, Roth A, Hornung V, Hagmann CA, Wimmenauer V, et al. (2009). "Recognition of 5'-triphosphate by RIG-I helicase requires short blunt double-stranded RNA as contained in panhandle of negative strand virus". Immunity. 31 (1): 25–34. doi:10.1016/j.immuni.2009.05.008. PMC   2824854 . PMID   19576794.
  45. 1 2 Angel M, Yanik MF (2010). "Innate Immune Suppression Enables Frequent Transfection with RNA Encoding Reprogramming Proteins". PLOS ONE. 5 (7): e11756. Bibcode:2010PLoSO...511756A. doi: 10.1371/journal.pone.0011756 . PMC   2909252 . PMID   20668695.
  46. Herb M, Farid A, Gluschko A, Krönke M, Schramm M (November 2019). "Highly Efficient Transfection of Primary Macrophages with In Vitro Transcribed mRNA". Journal of Visualized Experiments (153). doi: 10.3791/60143 . PMID   31762462.
  47. Trafton A (26 July 2010). "RNA offers a safer way to reprogram cells". MIT News Office.

Further reading