Otago Researchers Develop Innovative Phage Therapy for Bacterial Diseases

Researchers at the University of Otago are pioneering a new approach to combat bacterial diseases through the study of bacteriophages, which are viruses that specifically target and eliminate bacteria. Led by Prof Peter Fineran and Dr Robert Fagerlund, this innovative project aims to develop phage therapy for human use, with initial applications focusing on bacterial infections affecting New Zealand’s cherry orchards.

The project has received funding from the Ministry of Business, Innovation and Employment (MBIE), allowing the team to explore solutions to significant agricultural challenges. One of the primary threats is Pseudomonas bacteria, which can result in losses of between 20% and 50% in young orchards. Traditionally, growers have relied on copper sprays for control, but this method is increasingly ineffective as bacteria develop resistance and the sprays adversely affect other beneficial microbes.

To address this issue, the research team is developing specialized phage cocktails. These cocktails consist of multiple phages, each equipped with a different mechanism to breach bacterial defenses. “If one phage is blocked, another still gets through,” said Prof Fineran. This strategy aims to create a more robust treatment that also minimizes the emergence of bacterial resistance.

Targeted Solutions for Human and Animal Pathogens

The principles of phage therapy extend beyond agriculture. Prof Fineran emphasized that the methodologies being researched are applicable to both human and animal pathogens. The team’s recent discoveries include “jumbo phages,” which construct protective protein shells inside bacteria, providing a secure environment for phage replication, insulated from bacterial enzymes.

Additionally, the researchers have identified phages that can shield their DNA with sugars, preventing attacks from CRISPR, a prominent gene-editing technology. Some phages utilize one sugar for protection, while others employ multiple sugars, each offering defense against different bacterial mechanisms. These resilient phages are promising candidates for future treatments, as they naturally evade bacterial defenses.

Currently, phage therapy is being tested in hospitals across Western countries as a last resort for treating persistent infections. While phages are also gaining traction in mainstream agriculture, Prof Fineran cautioned that they are not a “silver bullet.” Instead of replacing antibiotics and other treatment methods, phages are likely to serve as a complementary approach, enhancing existing therapies.

“To achieve the desired outcomes, we must carefully select the right phages and deepen our understanding of bacterial immune systems and how phages overcome them,” Prof Fineran noted. This ongoing research is critical for developing effective phage therapies that could ultimately improve human health and agricultural productivity.

As the project progresses, the team is optimistic about the potential for phage therapy to transform the treatment of bacterial diseases, offering a targeted and environmentally friendly alternative to traditional antibiotics.