New Immunotherapy Targets Bacterial Sugar to Combat Drug-Resistant Infections
Researchers in Australia have developed an antibody-based immunotherapy designed to combat drug-resistant bacteria by targeting a sugar molecule exclusive to bacterial cells. This groundbreaking development, detailed in a study published in Nature Chemical Biology, demonstrated the antibody's ability to eliminate lethal bacterial infections in mouse models, offering a potential new strategy against hospital-acquired infections.
This development offers a potential new strategy against hospital-acquired infections by eliminating lethal bacterial infections in mouse models.
Research Development
The research team was co-led by Professor Richard Payne from the University of Sydney, Professor Ethan Goddard-Borger at WEHI, and Associate Professor Nichollas Scott from the University of Melbourne and the Peter Doherty Institute. Their collaborative work focuses on developing novel methods to address the growing threat of antimicrobial resistance, particularly from pathogens that resist conventional antibiotics.
Target and Mechanism
The new antibody specifically targets pseudaminic acid, a unique sugar molecule produced solely by bacteria. This sugar is a crucial component of bacterial outer coats, which bacteria utilize to effectively evade host immune responses. Crucially, as humans do not produce this sugar, it presents a distinct and highly promising target for therapeutic intervention.
To develop this innovative therapy, the team meticulously synthesized the bacterial sugar and sugar-decorated peptides in the laboratory. This intricate process enabled them to determine the molecule's precise three-dimensional structure and understand how it is presented on bacterial surfaces. Using this vital structural information, they engineered a "pan-specific" antibody capable of recognizing the pseudaminic acid across a wide range of bacterial species and strains. The antibody functions by identifying this specific bacterial sugar, thereby signaling the pathogen for destruction by the host's immune system.
Pre-clinical Efficacy
In rigorous laboratory testing, the antibody successfully eliminated multidrug-resistant Acinetobacter baumannii in mouse infection models. Acinetobacter baumannii is a common and dangerous cause of hospital-acquired pneumonia and bloodstream infections globally, notorious for its resistance to even last-line antibiotics.
"Multidrug-resistant Acinetobacter baumannii poses a significant threat in modern healthcare due to its resistance to various antibiotics." — Professor Ethan Goddard-Borger
Future Outlook
This innovative approach is characterized as a form of "passive immunotherapy," involving the administration of pre-made antibodies to rapidly control an infection. This strategy holds significant potential for both therapeutic treatment of active infections and as a preventative measure, offering crucial protection to vulnerable patients, such as those in intensive care units.
The research team is ambitious, aiming to translate these promising findings into clinical antibody therapies specifically targeting multidrug-resistant A. baumannii within the next five years. This development is intended to represent a critical step in addressing antimicrobial resistance by targeting one of the key ESKAPE pathogens, a group of bacteria known for their high rates of multidrug resistance and severe clinical impact.