Summary
Urinary tract infections (UTIs) are a worsening global health problem. Multispecies bacterial UTIs are common but are poorly recognized and understood. Here we developed host cell co-infection models combined with high resolution imaging to compare single- and multi-species infections with common uropathogens, uropathogenic Escherichia coli (UPEC), Klebsiella pneumoniae and Enterococcus faecalis. We demonstrate cooperation and direct interactions specifically between UPEC and E. faecalis within host cells that corresponded to an increased frequency of host cell infection. 3D imaging showed UPEC rods orientated perpendicular to the major host cell axis within single-species intracellular bacterial communities (IBCs), whereas UPEC cells often enveloped E. faecalis in multispecies IBCs. Furthermore, during dispersal from host cells, only the Gram-negative bacteria underwent infection-related filamentation (IRF) in multispecies infections. These first insights into intra-species synergies during UTIs at a single cell level should provide research pathways towards better diagnosis and treatment.
Competing Interest Statement
The authors have declared no competing interest.
