The aim of this work was to study the cytotoxicity of different fractions of gold nanoparticles prepared by ultrasonic spray pyrolysis from gold scrap. The target cells were rat thymocytes, as a type of nonproliferating cells, and L929 mouse fibroblasts, as a type of continuous proliferating cells. Fractions1 and 2, composed of pure gold nanoparticles, as determined by scanning electron microscopy with a combination of energy dispersive X-ray analysis, were nontoxic for thymocytes, but reduced moderately the proliferative activity of L929 cells. The inhibitory effect of fraction 2, containing particles smaller in size than fraction 1, was stronger. Fraction 3, composed of Au and up to 3% Cu was noncytotoxic for thymocytes, but was cytotoxic for L929 cells. Fraction 4, composed of Au and Ag nanoparticles, and fraction 5, composed of Au together with Cu, Ni, Zn, Fe, and In were cytotoxic for both thymocytes and L929 cells. These results suggest that USP enables the synthesis of pure gold nanoparticles with controlled size, even from gold scrap. However, microstructural analyses and biocompatibility testing are necessary for their proper selection from more cytotoxic gold nanoparticles, contaminated with other elements of gold alloys.
COBISS.SI-ID: 14359830
We prepared 5 different fractions of nanoparticles from the gold scrap, by using a new technology, Ultrasonic Spray Pirolysis (USP).The aim of this study was to characterize the microstructure and cytotoxicity of the nanoparticles along with their immunomodulatory properties ,using Con-canvaline A (ConA)-treated rat splenocytes as a model of activated immune cells. Fractions 1 and 2 , composed of pure gold nanoparticles, although non-cytotoxic, reduced cellular proliferation. Fraction 2, containing particles smaller in size and lesser agglomerated than fraction 1, up-and down-regulated the production of IL-2 and IL-10, respectively, by activated splenocytes. Fraction 3, containing nanoparticles composed of Au and up to 3 at. % Cu, was non-cytotoxic, but reduced IL-2 production and cell proliferation. Fractions 4 and 5, contaminated with alloying elements from the gold scrap, were cytotoxic. The extent of cytotoxicity and subsequent reduction of cytokine production, as well as the mode of cell death, depended on their composition. In conclusion, we showed that USP enables the synthesis of gold nanoparticles, which could be suitable for various biological applications, and that ConA-treated splenocytes represent a reliable model for fast and accurate evaluation of the immunotoxicological profiles of these particles. However, it is necessary to improve this USP technology and investigate further some of the immunomodulatory mechanisms using more specific immunological tests.
COBISS.SI-ID: 15970838
Mesenchymal stem cells (MSCs) isolated from healthy dental tissues are being investigated as an alternative source of MSCs for the treatment of damaged tissues and inflammatory diseases. Here we investigated whether MSCs from periapical lesions (PL-MSCs) also possess multi-lineage differentiation capacity and immunomodulatory properties. PL-MSCs, isolated by collagenase/DNAse digestion from surgically extracted PLs, were compared with MSCs from non-inflamed dental pulp (DP-MSCs) and dental follicle (DF-MSCs) for their phenotype and multi-potent differentiation potential. The anti-inflammatory and immunomodulatory effects of PL-MSCs were studied in co-culture with peripheral blood mononuclear cells (PB-MNCs) and PL-inflammatory cells (PL-ICs). Results PL-MSCs were characterized by typical MSCs phenotype, lower clonogenicity and self-renewal rate, compared to DF-MSC sand DP-MSCs. These cells possess the potential to differentiate into adipocyte-, osteoblast- and chondrocyte-like cells in vitro, which differs from that of DP-MSCs and DF-MSCs. PL-MSCs inhibited phytohemaglutinine-induced proliferation of PB-MNCs and production of IL-2, IFN? and IL-5 in the co-culture, probably via TGF-ß-dependent mechanisms. These cells also suppressed the production of IL-1ß, IL-6, and TNF-? by PL-ICsvia soluble mediators, whereas the suppression of IL-8 production required a direct cell-to-cell contact. The differentiation potential of PL-MSCs and their immunosuppressive/anti-inflammatory properties could be beneficial for the treatment of chronic periodontal diseases.
COBISS.SI-ID: 16056854