Human PMNs exhibit greater phagocytosis, NETosis, and enhanced migration towards nontypeable Haemophilus influenzae newly released from biofilms Wilbanks et al.

A monoclonal antibody against an essential biofilm matrix protein induces rapid biofilm collapse with release of bacteria into a highly vulnerable phenotype. Newly released (‘NRel’) bacteria are significantly more sensitive to antibiotic-, PMN-, or antimicrobial peptide-mediated killing in vitro, and are rapidly eradicated in four animal models without antibiotic treatment, highlighting the role of innate immune effectors.

Here, we characterize PMN-mediated activity against three clinical isolates of nontypeable Haemophilus influenzae NRel. Indeed, NTHI was most sensitive in the NRel state to both PMN-mediated phagocytosis and NETosis elimination. Moreover, PMNs incubated with NTHI NRel released significantly more IL-8 to recruit additional PMNs.