Chimera (virus)
A chimera virus is an artificial man-made product, and defined by the Center for Veterinary Biologics (part of the U.S. Department of Agriculture's Animal and Plant Health Inspection Service) as a "new hybrid microorganism created by joining nucleic acid fragments from two or more different microorganisms in which each of at least two of the fragments contain essential genes necessary for replication."[1] The term genetic chimera had already defined been to mean: an individual organism whose body contained cell populations from different zygotes or an organism that developed from portions of different embryos. Chimeric flaviviruses have been created in an attempt to make novel live attenuated vaccines.[2]
Etymology
In mythology, a chimera is a creature such as a hippogriff or a gryphon formed from parts of different animals, thus the name for these viruses.
As a bioweapon
Combining two pathogenic viruses increases the lethality of the new virus[3] which is why there have been cases where chimeric viruses have been considered for use as a bioweapon. For example, the Soviet Union's Chimera Project attempted to combine DNA from Venezuelan equine encephalitis, smallpox and Ebola virus in the late 1980s.[4] A combination smallpox and monkeypox virus has also been studied.[3]
As a medical treatment
Studies have shown that chimeric viruses can also be developed to have medical benefits. The US Food and Drug Administration (FDA) has recently approved the use of chimeric antigen receptor (CAR) to treat relapsed non-Hodgkin Lymphoma. By introducing a chimeric antigen receptor into T cells, the T cells become more efficient at identifying and attacking the tumor cells.[5] Studies are also in progress to create a chimeric vaccine against four types of Dengue virus, however this has not been successful yet.[6]
References
- Hill, Richard E. Jr (8 December 2005). "Center for Veterinary Biologics Notice No. 05-23" (PDF). United States Department of Agriculture. Animal and Plant Health Inspection Service - Center for Veterinary Biologics.
- Lai, C. J; Monath, T. P (2003). "Chimeric flaviviruses: novel vaccines against dengue fever, tick-borne encephalitis, and Japanese encephalitis". Adv Virus Res. Advances in Virus Research. 61: 469–509. doi:10.1016/s0065-3527(03)61013-4. ISBN 9780120398614. PMID 14714441.
- Collett, Marc S. (2006). "Impact of Synthetic Genomics on the Threat of Bioterrorism with Viral Agents". Working Papers for Synthetic Genomics: Risks and Benefits for Science and Society: 83–103.
- Ainscough, Michael J. (2004). "Next Generation Bioweapons: Genetic Engineering and BW" (PDF). Retrieved 9 September 2020.
- Lulla, Premal D.; Hill, LaQuisa C.; Ramos, Carlos A.; Heslop, Helen E. (2018). "The use of chimeric antigen receptor T cells in patients with non-Hodgkin lymphoma". Clinical Advances in Hematology and Oncology. 16 (5): 375–386. PMC 6469642. PMID 29851933.
- US Grant US10053493B2, William Messer; Aravinda De Silva & Boyd Yount, "Methods and compositions for dengue virus vaccines", published 2014, issued 2018, assigned to University of North Carolina at Chapel Hill