Selection of DNA Aptamers for Differentiation of Human Adipose-Derived Mesenchymal Stem Cells from Fibroblasts.

In recent years, stem cell therapy has shown promise in regenerative medicine. The lack of standardized protocols for cell isolation and differentiation generates conflicting results in this field. Mesenchymal stem cells derived from adipose tissue (ASC) and fibroblasts (FIB) share very similar cell membrane markers. In this context, the distinction of mesenchymal stem cells from fibroblasts has been crucial for safe clinical application of these cells. In the present study, we developed aptamers capable of specifically recognize ASC using the Cell-SELEX technique. We tested the affinity of ASC aptamers compared to dermal FIB. Quantitative PCR was advantageous for the in vitro validation of four candidate aptamers. The binding capabilities of Apta 2 and Apta 42 could not distinguish both cell types. At the same time, Apta 21 and Apta 99 showed a better binding capacity to ASC with dissociation constants (Kd) of 50.46 ± 2.28 nM and 72.71 ± 10.3 nM, respectively. However, Apta 21 showed a Kd of 86.78 ± 9.14 nM when incubated with FIB. Therefore, only Apta 99 showed specificity to detect ASC by total internal reflection microscopy (TIRF). This aptamer is a promising tool for the in vitro identification of ASC. These results will help understand the differences between these two cell types for more specific and precise cell therapies.

Restraint of Human Skin Fibroblast Motility, Migration, and Cell Surface Actin Dynamics, by Pannexin 1 and P2X7 Receptor Signaling.

Wound healing is a dynamic process required to maintain skin integrity and which relies on the precise migration of different cell types. A key molecule that regulates this process is ATP. However, the mechanisms involved in extracellular ATP management are poorly understood, particularly in the human dermis. Here, we explore the role, in human fibroblast migration during wound healing, of Pannexin 1 channels and their relationship with purinergic signals and in vivo cell surface filamentous actin dynamics. Using siRNA against Panx isoforms and different Panx1 channel inhibitors, we demonstrate in cultured human dermal fibroblasts that the absence or inhibition of Panx1 channels accelerates cell migration, increases single-cell motility, and promotes actin redistribution. These changes occur through a mechanism that involves the release of ATP to the extracellular space through a Panx1-dependent mechanism and the activation of the purinergic receptor P2X7. Together, these findings point to a pivotal role of Panx1 channels in skin fibroblast migration and suggest that these channels could be a useful pharmacological target to promote damaged skin healing.

Human adipose-derived stromal/stem cells are distinct from dermal fibroblasts as evaluated by biological characterization and RNA sequencing.

Human adipose-derived stromal/stem cells (ASC) have immunomodulatory properties and the potential to differentiate into several cell lines, important for application in regenerative medicine. However, the contamination with dermal fibroblasts (FIB) can impair the beneficial effects of ASC in cell therapy. It is then essential to develop new strategies that contribute to the distinction between these two cell types. In this study, we performed functional assays, high-throughput RNA sequencing (RNA-Seq) and quantitative PCR (qPCR) to find new markers that can distinguish ASC and FIB. We showed that ASC have adipogenic and osteogenic differentiation capacity and alkaline phosphatase activity, not observed in FIB. Gene expression variation analysis identified more than 2000 differentially expressed genes (DEG) between these two cell types. We validated 16 genes present in the list of DEG, including the alkaline phosphatase gene (ALPL). In conclusion, we showed that ASC and FIB have distinct biological properties as demonstrated by alkaline phosphatase activity and differentiation capacity, besides having different gene expression profiles. SIGNIFICANCE OF THE STUDY: Although many differences between stromal stem cells derived from human adipose tissue (ASC) and human dermal fibroblasts (FIB) are described, it is still difficult to find specific markers to differentiate them. This problem can interfere with the therapeutic use of ASC. This work aimed to find new markers to differentiate these two cell populations. Our findings suggest that these cells can be distinguished by biological and molecular characteristics, such as adipogenic and osteogenic differentiation, alkaline phosphatase activity and differential gene expression profiles. The DEG were related to the regulation of the cell cycle, development process, structural organization of the cell and synthesis of the extracellular matrix. This study helps to find new cellular markers to distinguish the two populations and to better understand the properties of these cells, which can improve cell therapy.

Cell investigation into the biocompatibility of adult human dermal fibroblasts with PCL nanofibers/TiO2 nanotubes on the surface of Ti-30Ta alloy for biomedical applications.

The polymer poly(ε-caprolactone) (PCL) has been used in the biomaterial field for its relatively inexpensive price and suitability for modification. Also, its chemical and biological properties are desirable for biomedical applications. The electrospinning process has been used for producing polymer fibers of PCL due in large part to an increased interest in nanoscale properties and technologies. Moreover, the use of biocompatible polymers for the viability of cell growth is a promising alternative to improve osseointegration. Characterization techniques such as scanning electron microscopy and contact angle were used for analyses of samples. Adult human dermal fibroblasts (neonatal) were utilized to evaluate the biocompatibility of the association of the electrospinning process of the biocompatible polymer (PCL) with TiO2 nanotubes on the Ti-30Ta alloy surface. The results of this study showed a favorable response for adhesion on the surface. This promising material is due to the modulation of the biological response.

Effects of Er-Miao-San extracts on TNF-alpha-indueed MMP-1 expression in human dermal fibroblasts

BACKGROUND: Various health benefits have been attributed to Er-Miao-San (EMS), a traditional Chinese herbal formulation that contains equal amounts of cortex phellodendri (Phellodendron amurense Ruprecht) and rhizoma atractylodis (Atractylodes lancea D.C). However, its effect on the anti-inflammatory activity in human dermal fibroblasts (HDFs) and the mechanism underlying this effect are unknown. RESULTS: This study investigated the effects of EMS on TNF-α-induced MMP-1 expression in HDFs. Our data show that EMS inhibited TNF-α-induced MMP-1 expression in a concentration-dependent manner. Interestingly, EMS maintained IkB content without inhibiting the phosphorylation of MAPKs, which are well-established upstream kinases of NF-kB. Moreover, EMS reduced the level of nuclear p65 protein in HDFs. Luciferase assay revealed that EMS inhibits the transcriptional activity of NF-kBbystabilizing IkB. Our results show that EMS exerts its anti-inflammatory effect by inhibiting NF-kB-regulated genes such as IL-1ß and IL-8. Moreover, EMS effectively inhibited TNF-α-induced expression of MMP-1 via the NF-kBpathway. CONCLUSIONS: Taken together, our data suggest that EMS could potentially be used as an anti-inflammatory and anti-aging treatment.

Hydrolyzable tannins from hydroalcoholic extract from Poincianella pluviosa stem bark and its wound-healing properties: phytochemical investigations and influence on in vitro cell physiology of human keratinocytes and dermal fibroblasts.

Extracts from Poincianella pluviosa stem bark are used in traditional medicine of South America for its wound healing properties. For validation of this traditional use and for rationalizing a potential pharmaceutical development towards standardized preparations bioassay-guided fractionation of EtOH-water (1:1v/v) extract (crude extract, CE) of P. pluviosa bark was performed. HaCaT keratinocytes cell line and human primary dermal fibroblasts (pNHDF) were used as in vitro systems. Significant stimulation of mitochondrial activity was found for CE on both cell types, which caused a strong increase of cell proliferation of keratinocytes. Fractionation of CE over Sephadex LH20 revealed two inactive fractions (FA and FB) and an active fraction FC, which was further fractionated by MPLC into 4 subfractions. Subfraction FC1 increased mitochondrial activity and proliferation of keratinocytes and dermal fibroblasts in a dose dependent manner (10 to 100 µg/mL) and did not show necrotic cytotoxicity on keratinocytes (LDH release assay). FC1 was investigated by ESI-MS/MS and solid-state (13)C NMR which confirmed the presence of various polyphenols and hydrolyzable tannins. MS studies suggest the presence of pyrogallol (1), gallic acid (2), gallic acid methyl ester (3), ellagic acid (4), corilagin (5), 1,4,6-tri-O-galloyl-glucose (6), tellimagrandin I (7), 1,2,3,6-tetra-O-galloyl-glucose (8), mallotinic acid (9), tellimagrandin II (10), 1,2,3,4,6-penta-O-galloyl-glucose (11), geraniin (12), and mallotusinic acid (13).