Editorial: Immune Response to Biofilms

Biofilms are one of the most widely distributed and successful form of microbial life and are associated to a significant amount of human infections (1). They typically contain aggregates of microorganisms adhering to a substrate and embedded in a self-produced matrix of extracellular polymeric substances. Importantly, biofilm-associated microorganisms exhibit an altered phenotype with respect to growth rate and gene transcription that provide them with unique characteristics as compared to their planktonic counterparts (2). These include the ability to resist antimicrobial treatments and host immune responses rendering biofilm-associated infections one of the major threats of the modern medicine. Despite the recognized clinical importance of biofilms, the vast majority of studies of the immune response against pathogens focuses on microorganisms in the planktonic state whereas the immune response against infectious biofilms has been far less investigated. There is evidence that the host immune response is only partially beneficial in clearing biofilm-associated infections if not even harmful by accelerating collateral tissue damage, as is seen in Pseudomonas aeruginosa biofilm-associated lung infections in Cystic Fibrosis (CF) patients (3). Therefore, it is critical to understand the complex interactions that establish between biofilms and the immune system as this may help in identifying new targets and strategies of immune intervention against biofilm-associated infections. We hope that this Research Topic may contribute to this purpose by collecting a number of papers (9 articles from 60 authors), exploring different aspects of the immune response to microbial biofilms.