"Nanochemistry and biotechnology"
Biocompatibility of silver nanoparticles with mesenchymal stromal cells under culturing

N.A. Volkova, E.V. Pavlovich, A.N. Goltsev
Institute for Problems of Cryobiology and Сryomedicine of the Natl. Acad. of Sci. of Ukraine, Pereyaslavskaya str. 23, Kharkov-61015, Ukraine.
E-mail: volkovana781@gmail.com

The biosafety is important to define of future therapeutic strategies in medicine with use of AgNPs. The effect of AgNPs on the proliferative, clonogenic potential and synthesis of collagen I type of bone marrow mesenchymal stromal cells (MSCs) was investigated.
The AgNPs (Sigma-Aldrich, USA) were obtained by citrate synthesis with an initial metal concentration of 20 μg/ml. The average size of AgNPs was 40 nm. The cells were incubated in nutritive medium supplemented with AgNPs in concentrations of 2, 4, 6, 10 μg/ml. MSCs were cultured in IMDM with 10% FBS for 14 days. An assessment of type I collagen content was performed with using monoclonal antibodies to type I collagen. The ability to colony formation was assessed by scoring the individual colonies comprised of at least 30 cells. Proliferative characteristics were examined by MTT-test. The results were processed with Student's t-test using Excel software.
	The use of AgNPs at concentrations of 2, 4 and 6 μg/mL did not effect morphological structure, proliferation and ability to colony formation of MSCs. The culture of MSCs was characterized by the presence of spindle-shaped and sail-shaped cells 89.6 ± 2.7 % of which were positively stained for collagen type I. The percentage of cells synthesizing collagen type I was decreased when adding AgNPs 6 and 10 μg/mL. The dynamics of MSCs growth in the control and groups with AgNPs at concentrations of 2 - 10 μg/ml was similar, but it differed in a rate. The use of AgNPs at concentration of 10 μg/ml a decreased proliferative and clonogenic potentials if compared with the control samples (without AgNPs). 
	Summarizing the obtained data we can conclude that slow concentration silver nanoparticles at concentration of 2 and 4 μg/ml did not lead to significant changes in the studied index during the entire period of observation. The obtained results are related to the field of applied nanotechnology,which extends to regenerative medicine, especially in development of bioimplantology.
This work has been supported by project No 70/18-Н NAS of Ukraine "Biosafety and efficiency of interaction of inert metal nanoparticles with mesenchymal stem cells of bone marrow".