Claudia Sperling1*, Manfred F. Maitz1, Liyu Chen2, Carsten Werner1

 

Hohe Str. 6
01069 Dresden
1Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials
Dresden, Germany
2Australian Institute for Bioengineering and Nanotechnology (AIBN)
Brisbane, Australia

 

Foreign materials in blood activate various inflammatory and coagulant response reactions. These reactions can be highly modified if materials are nanosized instead of macroscopic.

Nanoparticles are increasingly applied in the treatment of cancer and cardiovascular disease. Safety and efficacy depend on minimal interaction with blood cells and proteins and a low activation of body defense systems. Former work from us and others showed that surface characteristics like charge, hydrophilicity and certain surface groups lead to finely tuned body reactions like the activation of the blood contact system of the coagulation cascade, platelet adhesion / activation, complement fragment adsorption and neutrophil granulocytes adhesion. Some surface characteristics act synergistically on blood activation and therefore no easy conclusion from surface properties concerning hemocompatibility can be drawn. Recently we were able to show that adherent granulocytes can form neutrophil extracellular traps on hydrophobic surfaces and that this reaction can support coagulation. Additionally we detected activated Factor seven activating protease on the positively charged surface polyethylene imine which supports strong coagulation activation in our in vitro set up.

These reactions were tested on planar surfaces. Nanoparticles might react entirely different with blood proteins and cells. We set up reliable testing conditions with flowing fresh whole human blood2 and determined the hemocompatibility of silk as well as of hyperbranched polymeric nanoparticles with positive, negative and neutral charge. We showed that dispersed nanosized silk particles induced less complement activation than their aggregates or corresponding flat surfaces. For charged hyperbranched particles activation on the whole was low, yet anionic particles showed a significantly stronger activation of coagulation and platelets and complement activation was lowest for the neutral particles.

These results allow a first conclusion on differences between nanoparticle and planar surfaces concerning blood activation reactions.

 

 Sperling, C; Fischer, M.; Maitz, M.F.; Werner, C. Biomaterials Science 2017, DOI: 10.1039/c7bm00458c. Neutrophil extracellular trap formation upon exposure of hydrophobic materials to human whole blood causes thrombogenic reactions.

 

2 Maitz, M.F.; Sperling, C; Wongpinyochit, T.; Herklotz, M.; Werner, C.; Seib, F.P. Nanomedicine 2017, 10.1016/j.nano.2017.07.012. Biocompatibility assessment of silk nanoparticles: hemocompatibility and internalization by human blood cells.

 

Biographic Details

Dr. Claudia Sperling

Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials Dresden, Hohe Strasse 6, 01069 Dresden

Country: Germany

Phone: +49 4658 274 Fax: +49 4658 533  E-mail: sperling@ipfdd.de

Research interests: hemocompatibility, cell adhesion to biomaterials, protein adsorption