Phage Therapy Flashcards
What are bacteriophages?
A bacterial virus.
The most common type have double-stranded DNA genomes.
The majority lack a lipid envelope but are structurally complex.
The tails of a number of phage are contractile and are involved in the nucleic penetration of the host.
What is the infection cycle of phages?
Attachment (adsorption). Penetration (injection). Synthesis of nucleic acid and protein. Attachment (adsorption). Release (lysis). Assembly and packaging.
What is the mode of action of phages?
Strict parasite of bacteria.
Biological entities that have complex and co-evolving relationships with them.
Virulent phages which undergo lytic cycle.
For therapeutic use, necessary to isolate active phages, amplify them and then administer them in such a way that they come into contact with the pathogen.
Phages multiply when in contact with host bacteria, and will spread as long as there are cells left to infect.
Once pathogen is eliminated, the phages which cannot survive without a host are then degraded.
How could phages be used in the future?
Could also ne used as an alternative to traditional antimicrobials or used together (synergy).
Could also be used to decolonise patients before surgery or decolonise Staphylococcus aureus carriers.
What are the positives of phage therapy?
Personalised therapy.
Provides another option to treat infections.
Works well on resistant infections.
Allows bypassing of antibiotic resistance.
Specificity of phages allows for specific pathogen that causes the infection to be treated.
What are the drawbacks of phage therapy?
Cost to manufacture is high.
Not stable in solution.
Not available to start therapy immediately.
Long term effects can’t be predicted.
No specific regulations in place to guide its distribution / manufacture.
