Microbiology and Infection Research Group

Biofilms are sessile communities of microorganisms which are associated with chronic infections and are difficult to clear by the host immune system or with antibiotics. We utilise a range of static and flow-based methods to evaluate the ability of various pathogens to form biofilms on both biotic and abiotic surfaces. From this we are able to evaluate the efficacy of various compounds to either prevent or remove these resistant entities as well as elucidating their role in infectious disease.

In order to understand infectious disease, it is crucial to examine the interplay between pathogens and the host. We utilise a combination of in vitro cell culture-based methods and in vivo invertebrate models of infection to study host-pathogen interactions as well as analysing biological molecules directly from clinical samples.

The Galleria mellonella infection model provides a reliable and inexpensive means to examine the virulence of pathogens, as well as examining the efficacy of novel antimicrobial compounds in vivo. G mellonella on the left have received sterile saline, whereas those on the right have received a lethal dose of Pseudomonas aeruginosa.

Cytomegalovirus (CMV) infection is a leading cause of illness and death in individuals who have impaired or immature immune systems. It has been known for some time that cells of the immune system, Natural Killer (NK) cells, are particularly important for controlling CMV. However, NK cells are not able to clear CMV from an infected individual. Work by the IRG has shown that this is because CMV is able to evade recognition by NK cells. Our current research is focusing on identifying novel NK immunomodulatory functions encoded by CMV.

With the continued emergence of antibiotic-resistant pathogens, our research has centred on the evaluation of non-antibiotic agents (including honey and plant extracts) for topical use on wounds. We use both laboratory cultures and clinical samples to study the anitmicrobial effects of novel agents. We have discovered the mechanism by which manuka honey is able to eradicate methicillin-resistant Staphylococcus aureus (MRSA) from colonised wounds, which has encouraged clinicians across the world to adopt the use of manuka honey in chronic wound treatment. Our research has also highlighted the potential synergistic effect of manuka honey and antibiotics in inhibiting the growth of MRSA.

Ureaplasma species are the most frequently isolated pathogens from placental tissues of females presenting with preterm delivery, and are gaining increased recognition in the field of genitourinary medicine for a role in non-gonococcal urethritis. Our research has been concerned with monitoring levels of antibiotic resistance within patient populations, understanding how colonisation may result in symptomatic disease, and determining the mechanisms by which ureaplasmas are able to evade treatment and the host immune system.