TY - JOUR

T1 - Interactions between polymorphonuclear leukocytes and Pseudomonas aeruginosa biofilms on silicone implants in vivo

AU - van Gennip, Maria

AU - Hultqvist, Louise Dahl

AU - Alhede, Morten

AU - Qvortrup, Klaus

AU - Jensen, Peter Østrup

AU - Høiby, Niels

AU - Givskov, Michael

AU - Bjarnsholt, Thomas

PY - 2012/8

Y1 - 2012/8

N2 - Chronic infections with Pseudomonas aeruginosa persist because the bacterium forms biofilms that are tolerant to antibiotic treatment and the host immune response. Scanning electron microscopy and confocal laser scanning microscopy were used to visualize biofilm development in vivo following intraperitoneal inoculation of mice with bacteria growing on hollow silicone tubes, as well as to examine the interaction between these bacteria and the host innate immune response. Wild-type P. aeruginosa developed biofilms within 1 day that trapped and caused visible cavities in polymorphonuclear leukocytes (PMNs). In contrast, the number of cells of a P. aeruginosa rhlA mutant that cannot produce rhamnolipids was significantly reduced on the implants by day 1, and the bacteria were actively phagocytosed by infiltrating PMNs. In addition, we identified extracellular wire-like structures around the bacteria and PMNs, which we found to consist of DNA and other polymers. Here we present a novel method to study a pathogen-host interaction in detail. The data presented provide the first direct, high-resolution visualization of the failure of PMNs to protect against bacterial biofilms.

AB - Chronic infections with Pseudomonas aeruginosa persist because the bacterium forms biofilms that are tolerant to antibiotic treatment and the host immune response. Scanning electron microscopy and confocal laser scanning microscopy were used to visualize biofilm development in vivo following intraperitoneal inoculation of mice with bacteria growing on hollow silicone tubes, as well as to examine the interaction between these bacteria and the host innate immune response. Wild-type P. aeruginosa developed biofilms within 1 day that trapped and caused visible cavities in polymorphonuclear leukocytes (PMNs). In contrast, the number of cells of a P. aeruginosa rhlA mutant that cannot produce rhamnolipids was significantly reduced on the implants by day 1, and the bacteria were actively phagocytosed by infiltrating PMNs. In addition, we identified extracellular wire-like structures around the bacteria and PMNs, which we found to consist of DNA and other polymers. Here we present a novel method to study a pathogen-host interaction in detail. The data presented provide the first direct, high-resolution visualization of the failure of PMNs to protect against bacterial biofilms.

KW - Animals

KW - Biofilms

KW - DNA, Bacterial

KW - Female

KW - Genes, Bacterial

KW - Glycolipids

KW - Host-Pathogen Interactions

KW - Mice

KW - Mice, Inbred BALB C

KW - Microscopy, Confocal

KW - Microscopy, Electron, Scanning

KW - Mutation

KW - Neutrophils

KW - Phagocytosis

KW - Prosthesis-Related Infections

KW - Pseudomonas Infections

KW - Pseudomonas aeruginosa

KW - Silicones

U2 - 10.1128/IAI.06215-11

DO - 10.1128/IAI.06215-11

M3 - Journal article

C2 - 22585963

VL - 80

SP - 2601

EP - 2607

JO - Infection and Immunity

JF - Infection and Immunity

SN - 0019-9567

IS - 8

ER -