Cytokines Meet Phages: A Revolutionary Pathway to Modulating Immunity and Microbial Balance

Bacteriophages are a unique and fascinating group of viruses, known for their highly specific ability to infect and replicate within bacterial cells. While their potential as antibacterial agents has been recognized for decades, recent research has revealed complex interactions between phages and the human immune system, offering new insights into their role in immune modulation. New evidence reveals a dynamic and intricate relationship between phages and cytokines, suggesting their ability to regulate inflammation, immune tolerance, and host–pathogen interaction. Herein, we review how phages affect the production of cytokines and the behavior of immune cells indirectly by lysis of bacterium or directly on mammalian cells. Phages have been shown to induce both pro- and anti-inflammatory responses and recently, they have been explored in personalized immunotherapy, cancer immunotherapy, and microbiome modulation, which are the focus of this review. Several challenges remain despite significant progress, including practical obstructions related to endotoxins along with host microbiome variability and regulatory issues. Nevertheless, the potential of bacteriophages to modulate immune responses makes them attractive candidates for the future of precision medicine.