The Staphylococcus aureus collagen adhesin is a virulence determinant in experimental septic arthritis.
The importance of a collagen-binding adhesin in the pathogenesis of septic arthritis has been examined by comparing the virulence of two sets of Staphylococcus aureus mutants in an animal model. Collagen adhesin-negative mutant PH100 was constructed by replacing the chromosomal collagen adhesin gene (cna) in a clinical strain, Phillips, with an inactivated copy of the gene. Collagen adhesin-positive mutant S. aureus CYL574 was generated by introducing the cna gene into CYL316, a strain that normally lacks the cna gene. Biochemical, immunological, and functional analyses of the generated mutants and their respective parent strains showed that binding of 125I-labeled collagen, expression of an immunoreactive collagen adhesin, and bacterial adherence to cartilage were directly correlated with the presence of a functional cna gene. Greater than 70% of the mice injected with the Cna+ strains developed clinical signs of arthritis, whereas less than 27% of the animals injected with Cna- strains showed symptoms of disease. Furthermore, mice injected with the Cna+ strain Phillips had remarkably elevated levels of immunoglobulin G1 and interleukin-6 compared with mice injected with the Cna- mutant PH100. Taken together, these results demonstrate that collagen adhesin plays an important role in the pathogenesis of septic arthritis induced by S. aureus.
Patti
J M
JM
Center for Extracellular Matrix Biology, Texas A&M University, Houston 77030.
Bremell
T
T
Krajewska-Pietrasik
D
D
Abdelnour
A
A
Tarkowski
A
A
Rydén
C
C
Höök
M
M
D018829:Adhesins, Bacterial; D000818:Animals; D001170:Arthritis, Infectious / Q000382:microbiology*; D001422:Bacterial Adhesion / Q000502:physiology*; D001483:Base Sequence; D002356:Cartilage / Q000382:microbiology; D003094:Collagen; D017931:DNA Primers / Q000737:chemistry; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D005798:Genes, Bacterial; D005822:Genetic Vectors; D051379:Mice; D008969:Molecular Sequence Data; D013211:Staphylococcus aureus / Q000472:pathogenicity*
D018829:Adhesins, Bacterial; D017931:DNA Primers; D016326:Extracellular Matrix Proteins; C048165:adhesin, Staphylococcus aureus; D003094:Collagen