gms | German Medical Science

Deutscher Kongress für Orthopädie und Unfallchirurgie, 75. Jahrestagung der Deutschen Gesellschaft für Unfallchirurgie, 97. Tagung der Deutschen Gesellschaft für Orthopädie und Orthopädische Chirurgie, 52. Tagung des Berufsverbandes der Fachärzte für Orthopädie und Unfallchirurgie

25. - 28.10.2011, Berlin

The biological influence of nanosilver on peripheral blood mononuclear cells (PBMC)

Meeting Abstract

  • C. Greulich - Chirurgische Universitätsklinik Bergmannsheil, Bochum, Germany
  • J. Diendorf - Universität Duisburg-Essen, Anorganische Chemie, Essen, Germany
  • J. Gorenc - Chirurgische Universitätsklinik Bergmannsheil, Bochum, Germany
  • T. Schildhauer - Chirurgische Universitätsklinik Bergmannsheil, Bochum, Germany
  • M. Epple - Universität Duisburg-Essen, Anorganische Chemie, Essen, Germany
  • M. Köller - Chirurgische Universitätsklinik Bergmannsheil, Bochum, Germany

Deutscher Kongress für Orthopädie und Unfallchirurgie. 75. Jahrestagung der Deutschen Gesellschaft für Unfallchirurgie, 97. Tagung der Deutschen Gesellschaft für Orthopädie und Orthopädische Chirurgie, 52. Tagung des Berufsverbandes der Fachärzte für Orthopädie. Berlin, 25.-28.10.2011. Düsseldorf: German Medical Science GMS Publishing House; 2011. DocPO16-106

DOI: 10.3205/11dkou636, URN: urn:nbn:de:0183-11dkou6366

Veröffentlicht: 18. Oktober 2011

© 2011 Greulich et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielfältigt, verbreitet und öffentlich zugänglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Questionnaire: Silver nanoparticles (Ag-NP) are increasingly used in biomedical applications due to their remarkable antimicrobial activity. In biomedicine, Ag-NP are used as coatings or embedded into wound dressings, surgical instruments, and bone substitute biomaterials, such as silver-containing calcium phosphate cements. Ag-NP will be released after resorption of a biomaterial or from coatings and then may come into close contact with blood cells. Despite the widespread use of Ag-NP, there is a serious lack of information on the biological effects of Ag-NP on human blood cells. Therefore, we investigated the biological effects of Ag-NP at non-toxic concentrations on human peripheral blood mononuclear cells (PBMC). PBMC mainly consist of lymphocytes (e.g. T-cells) and monocytes. In this study the uptake of Ag-NP by monocytes and lymphocytes was analyzed, and the influence of nanosilver on cell-biological functions (proliferation, expression of adhesion molecules, cytokine release and generation of reactive oxygen species) was studied.

Methods: PVP-coated Ag-NP (spherical, Ø<75 nm) were synthesized by reduction with glucose. PBMC were isolated by a single step procedure based on a discontinuous double Ficoll-gradient. Freshly isolated cells were cultured at 37 °C for 24 h in the presence or absence of different concentrations of Ag-NP or silver ions to separate the particle and ion effect. Silver treated PBMC were analyzed for the particle uptake by using phase-contrast microscopy, flow cytometry and FIB/SEM. The generation of reactive oxygen species from silver-treated PBMC was measured by the oxidant-sensitive dye DCFH-DA. The cytokine release (IL-1ra, IL-6, IL-8 and TNF-a) of silver-treated PBMC was quantified by ELISA. For analyzing the expression of adhesion molecules different fluorochrome-labeled antibodies were used.

Results and Conclusions: We have shown that the uptake rate of Ag-NP and the cell activation after exposure of silver is a cell type-dependent process. Whereas, agglomerates of Ag-NP were detected within the cytoplasm of monocytes no agglomerated silver was found in T-cells. Obviously, only monocytes which have taken up Ag-NP showed a modulation of different biological function in contrast to lymphocytes. Thereby, a concentration-dependent activation (e.g. an increased expression of the adhesion molecule CD54) and generation of reactive oxygen species of monocytes at sub-toxic Ag-NP concentrations were observed. No modulation of T-cell-proliferation and activation was observed in the presence of Ag-NP. However when dissolved silver ions were used, T-cells were activated as well.

In conclusion our findings demonstrate the cell-type dependent cellular response of leukocytes towards silver and shows that cells which are able to accumulate nanosilver are activated by ROS-driven signal transduction mechanisms. Thereby, silver ions are very likely to act as the reactive silver species, because in the presence of silver ions T-cells were activated as well.