Bacteriophages, also called phages, are viruses that infect and kill bacteria, their natural hosts. But from a macromolecular perspective, phages can be viewed as nutrient-rich packets of nucleotides wrapped in an amino acid shell. A survey published on October 26m In Open Access Journal PLoS Biology Jeremy J. of Monash University, Victoria, Australia. Barr and colleagues suggested that mammalian cells internalize phages as a resource for cell growth and survival.
Phage interactions with bacteria are well known, and interactions between bacteria and their mammalian hosts can lead to various symbioses. However, the effects of bacteriophages on mammalian cellular and immunological processes are not well understood. To investigate how the immune system of mammalian cells interacts with and organizes phages, the researchers applied the well-studied phage T4 to mammalian cells. in vitro and analyzed cellular responses using luciferase reporter and antibody microarray assays. Phage-free supernatant served as a comparative control.
The researchers found that T4 phages did not activate DNA-mediated inflammatory pathways, but triggered a sequence of signaling pathway events that promoted cellular growth and survival. However, future studies are needed to determine why cells use phage particles as resources and whether they have specifically evolved adaptations to benefit from this internalization.
According to the authors, “This preliminary study provides novel insights into the effects of phages in mammalian systems with broad potential implications in the fields of immunology, phage therapy, the microbiome, and human health.”
This work provides new insights into the additional benefits that bacteriophages may have on their mammalian hosts. This is of particular importance given the increased use of phage therapy to treat antibiotic-resistant infections.”
Jeremy J Bar at Monash University
Bitchett, MC, etc (2023) Mammalian cells internalize bacteriophages and use them as a resource for cellular growth and survival.. PLoS Biology. doi.org/10.1371/journal.pbio.3002341.