Co-infection with the bacteria Pseudomonas aeruginosa and Mycobacterium abscessus, two common lung pathogens, can suppress the immune response and worsen the prognosis of patients with respiratory disease. This is the finding of a study published in the journal Virulence , which provides innovative insights into why polymicrobial infections are particularly difficult to treat.
The incidence of Mycobacterium abscessus infection is increasing in patients with cystic fibrosis, chronic obstructive pulmonary disease (COPD) and other chronic lung conditions, leading to accelerated deterioration of lung function. Surprisingly, 58-78% of patients with M. abscessus infection are also infected with Pseudomonas aeruginosa, the most common pathogen in these cases. However, it is not yet understood exactly how these two bacterial species interact during the process.
The new study involves experts from the UB, the Institute for Bioengineering of Catalonia (IBEC) and Universitat Autònoma de Barcelona (UAB). "We discovered that M. abscessus and P. aeruginosa mutually inhibit the progression of individual biofilms to form stable mixed biofilms", says Eduard Torrents, professor at the Department of Genetics, Microbiology and Statistics of the UB's Faculty of Biology and one of the main authors of the research. "Biofilms are communities of bacteria that clump together and secrete a protective matrix, which acts as a shield against antibiotics and the host immune system, making them a common cause of chronic infections", says Torrents, who is a senior researcher at IBEC's Bacterial Infections: Antimicrobial Therapies group and a member of ICREA Academia.
