gms | German Medical Science

German Congress of Orthopedic and Trauma Surgery (DKOU 2017)

24.10. - 27.10.2017, Berlin

Galleria mellonella as in vivo model to study implant-associated bacterial biofilms

Meeting Abstract

  • presenting/speaker Gopala Krishna Mannala - Laboratory of Experimental Trauma Surgery, University of Giessen, Giessen, Germany
  • Ursula Sommer - Laboratory of Experimental Trauma Surgery, University of Giessen, Giessen, Germany
  • Marian Kampschulte - Laboratory of Experimental Radiology, University of Giessen, Giessen, Germany
  • Katrin Susanne Lips - Laboratory of Experimental Trauma Surgery, University of Giessen, Giessen, Germany
  • Silke Zechel-Gran - Institute for Medical Microbiology, University of Giessen, Giessen, Germany
  • Eugen Domann - Institute for Medical Microbiology, University of Giessen, Giessen, Germany
  • Christian Heiss - Laboratory of Experimental Trauma Surgery, Department of Trauma Surgery, University Hospital of Giessen-Marburg, Campus Giessen, Giessen, Germany
  • Volker Alt - Laboratory of Experimental Trauma Surgery, Department of Trauma Surgery, University Hospital of Giessen-Marburg, Campus Giessen, Giessen, Germany

Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2017). Berlin, 24.-27.10.2017. Düsseldorf: German Medical Science GMS Publishing House; 2017. DocGR22-812

doi: 10.3205/17dkou569, urn:nbn:de:0183-17dkou5696

Published: October 23, 2017

© 2017 Mannala et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. See license information at http://creativecommons.org/licenses/by/4.0/.


Outline

Text

Objectives: In recent decades, metal implant materials are in extensive use in biomedical filed as medical devices and prostheses to assist or treat patients. Besides their applications, surfaces of these devices are colonized by various bacteria and form biofilms subsequently leads to persistent infections. Due to persistence infections, many cases lead to replacement of prostheses with new one. Intensive research is going on to reveal various molecular aspects of biofilm as well as to find out efficient drugs to treat biofilm-related infections. Several in vitro and in vivo models are established to investigate bacterial biofilms, but many mammalian in vivo models are ethically restricted to use. Since past decade, invertebrate models have been used to study host-pathogen interactions. One of such successful model is Galleria mellonella larvae which have been used to study the pathogenesis of bacterial and fungal pathogens as well as to screen antimicrobial compounds. Here, we aimed to use G. mellonella as in vivo biofilm model to study biofilm formation on metal implants and also to test the effect of silver nanoparticles on the biofilms.

Methods: G. mellonella larvae are maintained at 30 ° C on artificial diet in an incubator. Titanium and Stainless steel K-wires were cut into small pieces with size of 4mm. After sterilization with 100% alcohol, these K-wires were implanted inside the larva with help of scalpel and larvae were incubated at 30 ° C for two days. After 2 days, larvae were infected with Staphylococcus aureus (1X105 CFU) and incubated at 37 ° C for 2 days. On 2nd of post infection, the larvae were dissected; implant material is taken out and processed for enumeration of bacteria and transmission electron microscopy (TEM) for biofilm assessment. Later, the location of metal implant and biofilm development were analysed by micro-CT analysis. Further experiments are in progress to investigate the effect of silver nanoparticles on biofilms of implant materials.

Results and Conclusion: The results are very promising to use G. mellonella as in vivo model to study the biofilm formation on implanted materials. The implanted materials are not toxic to larvae, their growth and life stages are not affected by the implant materials. Bacterial enumeration from implanted material and TEM analysis showed the strong biofilm formation on them inside G. mellonella. Micro-CT analysis showed stable location of implanted materials. Further, prophylactic effect of silver nanoparticles on biofilms could show successful establishment of this cheap and reliable model to study biofilm related infections and to develop and test various antimicrobial compounds on the biofilms.