No abstract
Bacteriophages are viruses that grow within bacteria. Almost all bacteriophages can destroy (lyse) their bacterial host, although many are ‘temperate’ and can insert their genome into that of their bacterial host, a state referred to as lysogeny. Those that can only kill their host bacteria are termed ‘virulent’ and are preferred for therapeutic use. Lysis kills the bacterial host and releases the next generation of bacteriophages. This unique property allows localised amplification of a bacteriophage therapeutic, but only where its specific bacterial host is present. Bacteriophages are also able to target bacteria living within biofilms that can make them highly refractory to conventional antibiotics. Since their discovery in 1915, bacteriophages have been identified as having potential for the control of bacterial disease. Following the widespread appearance of resistance to conventional antibiotics, interest in this area has revived and the results of clinical trials of bacteriophage therapeutics are now being reported. Key Concepts: Bacteriophages are viruses that infect bacteria. Lytic bacteriophages kill their bacterial host rapidly, taking over host metabolism and producing a new generation of bacteriophages soon after infection. Newly produced bacteriophages can infect new host bacteria locally and can also spread to other sites of infection. This ability to kill bacteria led to their therapeutic use against bacterial infection in the pre‐antibiotic era. In most of the world, bacteriophages have been superseded since the 1940s by chemical antibiotics due to a combination of factors, including the limited understanding of basic bacteriophage biology and the far broader host ranges of chemical antibiotics. Despite many years of extensive clinical study in Eastern Europe and in earlier work in Europe and the United States, a lack of clinical trials meeting current regulatory requirements has limited the development of bacteriophage therapeutics. Interest in bacteriophages as therapeutics has been revived by the looming antibiotic resistance crisis, in an era when much more information is available about the older work and when phage biology is far better understood. Bacteriophage products for agricultural and food use are currently being marketed.
This chapter begins with an overview of the history of phage therapy as it pertains to non-wound infections, and then details more up-to-date experimental models (such as mice and dogs) and results. The following experimental infections are described: septicaemia, pulmonary infections, gastrointestinal infections, and canine otitis. A brief list of human uses of phage therapy is also provided.
Before any phage can be studied, or used for its biological properties, it must first be isolated. As such, isolation is a critical stepindeed, the critical stepin many explorations of phage biology and biotechnology. There are several techniques, both classical and modern, by which phages can be isolated, and selection of the proper method often depends on the intended use of the phage. In this chapter, we discuss the general principles of phage isolation and techniques to obtain pure phage isolates from a variety of sources, with a particular focus on the isolation of therapeutic phages. Thermophile Bacteria that grow at high temperatures, above the mesophilic range. Virulent A phage with an obligately lytic life cycle, in which successful infection is only followed by progeny production and cell lysis. There is no prophage state.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.