Bacterial interactions with proteins and cells relevant to the development of life-threatening endocarditis studied by use of a quartz-crystal microbalance.
Implant-related infections are a major challenge in clinical routine because of severe complications, for example infective endocarditis (IE). The purpose of this study was to investigate the real-time interaction of S. gordonii with proteins and cells important in the development of IE, in a flow system, by use of a quartz-crystal microbalance (QCM). Acoustic sensors were biologically modified by preconditioning with sterile saliva, platelet-poor plasma (PPP), or platelet-rich plasma (PRP), followed then by perfusion of a bacterial suspension. After perfusion, additional fluorescence and scanning electron microscopic (SEM) studies were performed. The surface structure of S. gordonii was analyzed by atomic force microscopy (AFM). Compared with S. gordonii adhesion on the abiotic sensor surface following normal mass loading indicated by a frequency decrease, adhesion on saliva, PPP, or PRP-conditioned sensors resulted in an increase in frequency. Furthermore, adhesion induced slightly increased damping signals for saliva and PPP-coated sensors but a decrease upon bacterial adhesion to PRP, indicating the formation of a more rigid biofilm. Microscopic analysis confirmed the formation of dense and vital bacterial layers and the aggregation of platelets and bacteria. In conclusion, our study shows that the complex patterns of QCM output data observed are strongly dependent on the biological substrate and adhesion mechanisms of S. gordonii. Overall, QCM sheds new light on the pathways of such severe infections as IE.
Department of Thoracic, Cardiac and Vascular Surgery, Clinical Research Laboratory, University Hospital Tübingen, Calwerstr. 7/1, 72076, Tübingen, Germany.
Stefanie
S
Krajewski
Johannes
J
Rheinlaender
Philip
P
Ries
Denis
D
Canjuga
Carmen
C
Mack
Lutz
L
Scheideler
Tilman E
TE
Schäffer
Jürgen
J
Geis-Gerstorfer
Hans-Peter
HP
Wendel
Frank
F
Rupp
D000162:Acoustics; D001422:Bacterial Adhesion; D018441:Biofilms; D015374:Biosensing Techniques; D001792:Blood Platelets / Q000378:metabolism*; D004548:Elasticity; D004696:Endocarditis / Q000175:diagnosis* / Q000382:microbiology*; D006046:Gold / Q000737:chemistry; D006801:Humans; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D010973:Platelet Adhesiveness; D053657:Platelet-Rich Plasma / Q000378:metabolism; D058525:Quartz Crystal Microbalance Techniques; D012463:Saliva / Q000378:metabolism / Q000382:microbiology; D054773:Streptococcus gordonii; D014783:Viscosity
D006046:Gold