Tumour-associated fibroblasts (TAFs) are part of the tumour stroma, providing functional and structural support for tumour progression and development. The origin and biology of TAFs are poorly understood, but within the tumour environment, TAFs become activated and secrete different paracrine and autocrine factors involved in tumorigenesis. It has been shown that bone marrow mesenchymal stem cells (MSCs) can be recruited into the tumours, where they proliferate and acquire a TAF-like phenotype. We attempted to determine to what extent TAFs characteristics in vitro juxtapose to MSCs’ definition, and we showed that TAFs and MSCs share immunophenotypic similarities, including the presence of certain cell surface molecules [human leukocyte antigen-DR subregion (HLA-DR), CD29, CD44, CD73, CD90, CD106 and CD117]; the expression of cytoskeleton and extracellular matrix proteins, such as vimentin, α-smooth muscle actin, nestin and trilineage differentiation potential (to adipocytes, chondrocytes and osteoblasts). When compared to MSCs, production of cytokines, chemokines and growth factors showed a significant increase in TAFs for vascular endothelial growth factor, transforming growth factor-β1, interleukins (IL-4, IL-10) and tumour necrosis factor α. Proliferation rate was highly increased in TAFs and fibroblast cell lines used in our study, compared to MSCs, whereas ultrastructural details differentiated the two cell types by the presence of cytoplasmic elongations, lamellar content lysosomes and intermediate filaments. Our results provide supportive evidence to the fact that TAFs derive from MSCs and could be a subset of ‘specialized’ MSCs.

Human skeletal muscle tissue displays specific cellular architecture easily damaged during individual existence, requiring multiple resources for regeneration. Congruent with local prerequisites, heterogeneous muscle stem cells (MuSCs) are present in the muscle interstitium. In this study, we aimed to characterize the properties of human muscle interstitial cells that had the characteristic morphology of telocytes (TCs). Immunocytochemistry and immunofluorescence showed that cells with TC morphology stained positive for c-kit/CD117 and VEGF. C-kit positive TCs were separated with magnetic-activated cell sorting, cultured in vitro and expanded for study. These cells exhibited high proliferation capacity (60% expressed endoglin/CD105 and 80% expressed nuclear Ki67). They also exhibited pluripotent capacity limited to Oct4 nuclear staining. In addition, 90% of c-kit positive TCs expressed VEGF. C-kit negative cells in the MuSCs population exhibited fibroblast-like morphology, low trilineage differential potential and negative VEGF staining. These results suggested that c-kit/CD117 positive TCs represented a unique cell type within the MuSC niche.

Context: Oleanolic and ursolic acids are antitumor and antibacterial agents which are extensively studied. Their major disadvantage is the poor water solubility which limits their applications. Objectives: Oleanolic and ursolic acid were encapsulated into polyurethane nanostructures that act as drug carriers. In order to evaluate the effectiveness of the particles, anti-microbial and anti-proliferative activity compared to un-encapsulated active compounds was tested. Materials and methods: Using an interfacial polycondensation technique, combined with spontaneous emulsification, structures with nanoscale dimensions were obtained. Scanning electron microscopy, differential scanning calorimetry and X-ray assays confirmed the encapsulation process. Concentrations of 10 and 30 lM particles and un-encapsulated compounds were tested by MTT viability assay for several breast cancer lines, with an exposure time of 72 h. For the antibacterial studies, the dilution method with MIC determination was used. Results: Ursolic acid had an excellent inhibitory effect with IC 50 value of 2.47, 1.20, 1.26 and 1.34 lM on MCF7, T47D, MDA-MB-231 and MDA-MB-361, respectively. Oleanolic acid did not show anti-proliferative activity. The pure compounds showed their antibacterial activity only against Bacillus species and Candida albicans, but MIC values were too high to be considered efficient antimicrobial agents (2280 and 4570 lg mL À 1 , respectively). Polyurethane nanoparticles which incorporated the agents did not show any biological activity. Discussion and conclusion: Although the active compounds did not fully exert their anti-proliferative activity following encapsulation inside polymeric nanoparticles, in vivo evaluation is needed in order to obtain an exhaustive conclusion, as the active compounds could be released as a result of metabolic activity. ARTICLE HISTORY

Introduction: The antimicrobial role of probiotic Lactobacillus casei subspecies casei DG (L. casei DG) and of the mix culture of probiotic Lactobacillus acidophilus LA-5 and Bifidobacterium BB-12 was tested on species of Staphylococcus, Streptococcus, Pasteurella, and Neisseria genera from supragingival sites from dogs with dental disease of different breed, age, sex, weight, and diet. The research was conducted on these four genera because of their importance in zoonotic infections after dog bites. Methodology: Species from Staphylococcus, Streptococcus, Pasteurella, and Neisseria genera were isolated and identified. To test the antimicrobial efficacy of L. casei DG and the mixed culture of probiotic L. acidophilus LA-5 and Bifidobacterium bifidum BB-12 on the pathogenic species, the agar overlay method was used. Results: L. casei DG had a bactericidal effect on all analyzed species isolated from Staphylococcus, Streptococcus, Pasteurella, and Neisseria genera after 24 hours of incubation. The mixed probiotic culture made up of L. acidophilus LA-5 and Bifidobacterium BB-12 species had no bactericidal effect on the species of Staphylococcus and Streptococcus genera, which were resistant. However, it had a bacteriostatic effect on several species of Pasteurella and Neisseria genera. Conclusions: This work highlights the antimicrobial potential of probiotics in vitro, demonstrating that the probiotic L. casei DG has a bactericidal effect on all analyzed species isolated from dental plaque and that the mix culture of probiotic L. acidophilus LA-5 and Bifidobacterium BB-12 has only a bacteriostatic effect.

Hematopoietic stem cells have a remarkable plastic capacity, which allows them to differentiate into various cells, such as immune cells, nervous cells, muscle cells, bone and cartilaginous cells. The aim of this study was to show the capacity of stem cells to differentiate into endothelial cells, in culture, after addition of endothelial cells growth suplement (ECGS). We also compared the behavior of these cells with that of endothelial cells obtained from human umbilical vein (HUVEC). CD34+ cells obtained by immunomagnetic separation from human umbilical cord and placental blood were used. After 12‐15 days of culture in a medium containing ECGS, the cells showed morphological changes characteristic to endothelial cells and immunocytochemical analysis revealed the presence of CD31 surface antigen and von Willebrand factor. The flow‐cytometric analysis of endothelial cells adhesion molecules (ECAM) showed that endothelial cells derived from CD34+ cells expressed CD54/ICAM‐1 9.65 ± 0.2% and CD106/VCAM 7.73±0.3%, values similar to those expressed by HUVECs. After TNF incubation, ECAM expression increased only in HUVECs. These data demonstrate that a fraction of circulating CD34+ cells may develop some endothelial cell characteristics when cultured with ECGS, but they are functionally different from HUVECs.