Chimera (virus)


A chimera virus is defined by the Center for Veterinary Biologics 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." The term chimera already referred to an individual organism whose body contained cell populations from different zygotes or an organism that developed from portions of different embryos. 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. Chimeric flaviviruses have been created in an attempt to make novel live attenuated vaccines.

As a bioweapon

Combining two pathogenic viruses increases the lethality of the new virus 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. A combination smallpox and monkeypox virus has also been studied.

As a medical treatment

Studies have shown that chimeric viruses can also be developed to have medical benefits. The US Food and Drug Administration has recently approved the use of chimeric antigen receptor 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. Studies are also in progress to create a chimeric vaccine against four types of Dengue virus, however this has not been successful yet.