In vivo

For other uses, see In Vivo (disambiguation).

This is a laboratory rat with a brain implant, that was used to record in vivo neuronal activity

Studies that are in vivo (Latin for "within the living"; often not italicized in English[1][2][3]) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, and plants, as opposed to a tissue extract or dead organism. This is not to be confused with experiments done in vitro ("within the glass"), i.e., in a laboratory environment using test tubes, Petri dishes, etc. Examples of investigations in vivo include: the pathogenesis of disease by comparing the effects of bacterial infection with the effects of purified bacterial toxins; the development of non-antibiotics, antiviral drugs, and new drugs generally; and new surgical procedures. Consequently, animal testing and clinical trials are major elements of in vivo research. In vivo testing is often employed over in vitro because it is better suited for observing the overall effects of an experiment on a living subject. In drug discovery, for example, verification of efficacy in vivo is crucial, because in vitro assays can sometimes yield misleading results with drug candidate molecules that are irrelevant in vivo (e.g., because such molecules cannot reach their site of in vivo action, for example as a result of rapid catabolism in the liver).[4]

The English microbiologist Professor Harry Smith and his colleagues in the mid-1950s found that sterile filtrates of serum from animals infected with Bacillus anthracis were lethal for other animals, whereas extracts of culture fluid from the same organism grown in vitro were not. This discovery of anthrax toxin through the use of in vivo experiments had a major impact on studies of the pathogenesis of infectious disease.

The maxim in vivo veritas ("in a living thing [there is] truth")[5] is a play on in vino veritas, ("in wine [there is] truth"), a well-known proverb.

  1. ^ Merriam-Webster, Merriam-Webster's Collegiate Dictionary, Merriam-Webster, archived from the original on 2020-10-10, retrieved 2014-04-20.
  2. ^ Iverson C, Flanagin A, Fontanarosa PB, Glass RM, Gregoline B, Lurie SJ, Meyer HS, Winker MA, Young RK, eds. (2007). "12.1.1 Use of Italics". AMA Manual of Style (10th ed.). Oxford, Oxfordshire: Oxford University Press. ISBN 978-0-19-517633-9.
  3. ^ American Psychological Association (2010), "4.21 Use of Italics", The Publication Manual of the American Psychological Association (6th ed.), Washington, DC: APA, ISBN 978-1-4338-0562-2
  4. ^ Atanasov AG, Waltenberger B, Pferschy-Wenzig EM, Linder T, Wawrosch C, Uhrin P, et al. (December 2015). "Discovery and resupply of pharmacologically active plant-derived natural products: A review". Biotechnology Advances. 33 (8): 1582–1614. doi:10.1016/j.biotechadv.2015.08.001. PMC 4748402. PMID 26281720.
  5. ^ "Life Science Technologies, Cell Signaling: In Vivo Veritas". Science Magazine. 2007. doi:10.1126/science.316.5832.1763. Retrieved 2023-12-11.