Multi-strain phage induced clearance of bacterial infections

Jacopo Marchi1, Chau Nguyen Ngoc Minh2, Laurent Debarbieux3

  • 1Department of Biology, University of Maryland, College Park, MD, USA.

Insights

Phage therapy uses viruses to kill bacteria. Using phage cocktails, especially in immunocompromised patients, can improve treatment outcomes and prevent bacteria from developing resistance to multiple phages simultaneously.

Area of Science:

  • Microbiology
  • Virology
  • Computational Biology

Background:

  • Antibiotic resistance is a growing threat, driving interest in phage therapy as an alternative treatment.
  • Bacteria can evolve resistance to bacteriophages (phages), challenging the long-term efficacy of phage therapeutics.
  • Phage cocktails, mixtures of multiple phages, are proposed to mitigate the emergence of phage-resistant bacterial mutants.

Purpose of the Study:

  • To investigate the efficacy of phage cocktails against bacterial infections using theoretical and computational models.
  • To analyze how phage cocktails perform compared to single-phage treatments, considering factors like bacterial resistance and host immunity.
  • To explore the impact of phage traits and receptor complementarity on therapeutic outcomes in both immunocompetent and immunocompromised hosts.

Main Methods:

  • Development and application of computational models simulating in vivo phage therapy.
  • Utilizing a two-phage cocktail model inspired by Pseudomonas aeruginosa and phages LUZ19v and PAK_P1, which target different surface receptors.
  • Performing Luria-Delbrück fluctuation tests to confirm the low probability of simultaneous resistance evolution.

Main Results:

  • Phage cocktails targeting independent bacterial receptors enhance treatment outcomes, particularly in immunocompromised hosts.
  • Cocktails significantly reduce the likelihood of bacteria evolving simultaneous resistance to multiple phages.
  • Therapeutic efficacy is robust across variations in phage-bacteria interactions and host immune responses.

Conclusions:

  • Phage cocktails offer a promising strategy to overcome bacterial resistance in phage therapy.
  • The design of effective phage cocktails should consider viral life history traits and receptor complementarity.
  • Computational modeling is a valuable tool for optimizing phage cocktail deployment in clinical settings.

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