プラスミドDNAの組換えインフルエンザウイルスの生成
Summary
プラスミドDNAからのインフルエンザウイルスの救助は、インフルエンザの研究者がインフルエンザウイルスの生物学のさまざまな側面を研究するために組換えウイルスを生成するために、そして潜在的なベクトルまたはワクチンとして使用することを可能にする基本的かつ本質的な実験的な手法です。
Abstract
インフルエンザ研究グループの数による努力はインフルエンザウイルスの逆遺伝学の発展と向上に極めて重要なされている。もともと1999年に設立さ<sup> 1,2</sup具体的な質問は、遺伝子組み換え、感染症、組換えインフルエンザウイルスによって応答されているため、組換えウイルスを生成するために>プラスミドベースの逆遺伝学的手法では、インフルエンザの研究分野に革命をもたらしています。このような研究は、ウイルス複製、ウイルスタンパク質の機能、ウイルスの複製および/または病原性のウイルスタンパク質に特異的変異の寄与と、また、外来タンパク質を発現する組換えインフルエンザウイルスを用いてウイルスベクターが含まれています<sup> 3</sup>。
Protocol
Discussion
プラスミドDNAから組換えインフルエンザウイルスの救助は、プロトコルが日常的に実験室で実施されると、シンプルかつ簡単なプロセスですが、初めに、複数の物事が間違って行くことができます。それは、ウイルスを生成するために適切なプラスミド調製を持つことが不可欠です。細胞株（293TとMDCK）の適切な維持管理が成功したウイルスの救助のための非常に重要です。伝統的に、遺伝?…
Divulgaciones
The authors have nothing to disclose.
Acknowledgements
著者らは、インフルエンザの逆遺伝学技術とプラスミドの開発のためのアドルフォガルシア、サストレとピーターPaleseの研究室で過去と現在のメンバーに感謝したいと思います。 AG – Sの研究室で研究の一部は手足の不自由な人、インフルエンザの研究と監視のための優秀NIAID資金によるセンター（HHSN266200700010C）によっておよび大学評価学位授与機構の助成金R01AI046954、U01AI070469とP01AI058113によって賄われています。 LM – Sのラボの研究は、部分的にNIAIDの助成金RO1AI077719によって運営されている。
Materials
| Material Name | Tipo | Company | Catalogue Number | Comment |
|---|---|---|---|---|
| DMEM | Invitrogen | 11995-065 | Store at 4°C | |
| OptiMEM | Invitrogen | 51985-034 | Store at 4°C | |
| Lipofectamine 2000 (LPF2000) | Invitrogen | 11668-019 | Store at 4°C | |
| TPCK-trypsin | Sigma | T-8802 | Store at -20°C | |
| Bovine Albumin (BA) | Sigma | A7979 | Store at 4°C | |
| Trypsin-EDTA | Invitrogen | 25300-054 | Store at -20°C | |
| Penicillin/Streptomycin (PS) 100X | Invitrogen | 15140-122 | Store at -20°C | |
| Fetal Bovine Serum (FBS) | Hyclone | SH30070.03 | Store at -20°C | |
| V-bottom 96-weel plates | Nunc | 249570 |
Cell lines
293T (catalogue number CRL-11268) and MDCK (catalogue number CCL-34) cell lines are maintained in a 37°C incubator with 5% CO2 in DMEM 10% FBS, 1% PS. Cells are available form the American Type Culture Collection (ATCC, 10801 University Boulevard, Manassas, VA. 20110-2209 USA).
Embryonated chicken eggs
Embryonated 10-day-old chicken eggs can be obtained from Charles River Laboratories, Specific Pathogen Fee Avian Supply (SPAFAS) Avian Products and Services. Franklin Commons, 106 Route 32, North Franklin, CT 06254 USA. Eggs are incubated at 37°C preceding and after viral infection. Before and after viral infection, eggs are candled to determine viability of the embryos. It is very important to look for dead eggs before and after viral infection. Before infection a dead egg can be easily spotted by the absence of blood vessels as well as the absence of embryo mobility. When candled, live embryos move. After viral infection a dead egg (probably related to influenza virus infection) will be easily spotted by the bad appearance of the egg as seen by the smaller and bloody volume of allantoic fluid. Infected-eggs are discarded in double autoclavable bags and autoclaved following standard procedures.
Chicken red blood cells (RBC)
Chicken RBC can be purchased from Truslow Farms, 201 Valley Road, Chestertown, Md 21620. Store at 4°C. For HA assays, wash 5 ml of the chicken RBC with 45 ml of PBS 1X in a 50 ml centrifuge tube. Centrifuge for 5 minutes at 1000 rpms, RT. Discard carefully the supernatant and use a 1:1000 dilution of the pelleted RBC in PBS 1X (final concentration of 0.5-1.0% RBC).
Tissue culture supernatants and allantoic fluids
Both, tissue culture supernatants and allantoic fluids can be stored at 4°C for a short period of time. After confirming virus rescue, viruses from cell supernatants or allantoic fluid are stored at -80°C.
Plasmids
All plasmids are prepared using a plasmid maxi kit following manufacturer’s recommendations. All plasmids are aliquot at concentrations of 1 μg/ml in ddH2O and stored at -20°C. For short-term storage, the plasmid can be keep at 4°C. The concentration of the purified DNA plasmid is determined by spectrophotometry at 260 nm, with purity being estimated using the 260:280 nm ratio. Preparations with 1.8-2.0 260:280 nm ratios are considered appropriated for virus rescue purposes. Additionally, plasmid concentration and purity should be confirmed with agarose gel chromatography. Ambisense pDZ plasmids (6) containing the eight influenza A/PR/8/34 viral genes (7) are illustrated in Figure 2.
Viruses
The described protocol for rescuing influenza A/PR/8/34 can be performed under biosafety level (BSL) 2 conditions. Contaminated material, including tissue culture supernatants and embryonated eggs, should be sterilized before disposal. Rescue of other influenza virus may require higher BSL conditions and, therefore, special conditions/security measurements will need to be followed.
Tissue culture media and solutions
DMEM 10%FBS 1%PS: 445 ml Dulbecco’s modified Eagle’s medium (DMEM), 50 ml of Fetal Bovine Serum (FBS), and 5 ml of 100X Penicillin/Streptomycin (PS). Store at 4°C. This media will be used to maintain 293T and MDCK cells as well as for the transfections. DMEM 0.3%BA 1%PS: 495.7 ml of DMEM, 4.3 ml of 35% Bovine Albumin (BA). Store at 4°C. Just before use, add TPCK treated trypsin to a final concentration of 1 μg/ml. Infectious media.
10X Phosphate buffered saline (PBS): 80 g of NaCl, 2 g of KCl, 11.5 g of Na2HPO4.7H2O, 2 g of KH2PO4. Add ddH2O up to 1 liter. Adjust pH to 7.3. Sterilize by autoclave. Store at room temperature.
1X PBS: Dilute 10X PBS 1:10 with ddH2O. Sterilize by autoclave and store at room temperature.
Referencias
- Neumann, G., Watanabe, T., Ito, H., Watanabe, S., Goto, H., Gao, P., Hughes, M., Perez, D. R., Donis, R., Hoffmann, E., Hobom, G., Kawaoka, Y. Generation of influenza A viruses entirely from cloned cDNAs. Proc Natl Acad Sci U S A. 96, 9345-9350 (1999).
- Fodor, E., Devenish, L., Engelhardt, O. G., Palese, P., Brownlee, G. G., Garcia-Sastre, A. Rescue of influenza A virus from recombinant DNA. J Virol. 73, 9679-9682 (1999).
- Martinez-Sobrido, L., Garcia-Sastre, A. Recombinant influenza virus vectors. Future Virology. 2, 401-416 (2007).
- Palese, P., Shaw, M. L., Knipe, D. M., Howley, P. H. Orthomyxoviridae. The viruses and their replication. Fields Virology. , 1647-1689 (2006).
- Schickli, J. H., Flandorfer, A., Nakaya, T., Martinez-Sobrido, L., Garcia-Sastre, A., Palese, P. Plasmid-only rescue of influenza A virus vaccine candidates. Philos Trans R Soc Lond B Biol Sci. 356, 1965-1973 (2001).
- Quinlivan, M., Zamarin, D., Garcia-Sastre, A., Cullinane, A., Chambers, T., Palese, P. Attenuation of equine influenza viruses through truncations of the NS1 protein. J Virol. 79, 8431-8439 (2005).
- Niwa, H., Yamamura, K., Miyazaki, J. Efficient selection for high-expression transfectants with a novel eukaryotic vector. Gene. 108, 193-199 (1991).
