Differentiation of human hair follicle stem cells into endothelial cells induced by vascular endothelial and basic fibroblast growth factors

Hair follicle stem cells promote epidermal regeneration under expanded condition

Skin soft tissue expansion is the process of obtaining excess skin mixed with skin development, wound healing, and mechanical stretching. Previous studies have reported that tissue expansion significantly induces epidermal proliferation throughout the skin. However, the mechanisms underlying epidermal regeneration during skin soft tissue expansion are yet to be clarified. Hair follicle stem cells (HFSCs) have been recognized as a promising approach for epidermal regeneration. This study examines HFSC-related epidermal regeneration mechanisms under expanded condition and proposes a potential method for its cellular and molecular regulation.

Bee Venom Stimulates Growth Factor Release from Adipose-Derived Stem Cells to Promote Hair Growth

Limited evidence suggests that stimulating adipose-derived stem cells (ASCs) indirectly promotes hair growth. We examined whether bee venom (BV) activated ASCs and whether BV-induced hair growth was facilitated by enhanced growth factor release by ASCs. The induction of the telogen-to-anagen phase was studied in mice. The underlying mechanism was investigated using organ cultures of mouse vibrissa hair follicles. When BV-treated ASCs were injected subcutaneously into mice, the telogen-to-anagen transition was accelerated and, by day 14, the hair weight increased. Quantitative polymerase chain reaction (qPCR) revealed that BV influenced the expression of several molecules, including growth factors, chemokines, channels, transcription factors, and enzymes. Western blot analysis was employed to verify the protein expression levels of extracellular-signal-regulated kinase (ERK) and phospho-ERK. Both the Boyden chamber experiment and scratch assay confirmed the upregulation of cell migration by BV. Additionally, ASCs secreted higher levels of growth factors after exposure to BV. Following BV therapy, the gene expression levels of alkaline phosphatase (ALP), fibroblast growth factor (FGF)-1 and 6, endothelial cell growth factor, and platelet-derived growth factor (PDGF)-C were upregulated. The findings of this study suggest that bee venom can potentially be utilized as an ASC-preconditioning agent for hair regeneration.

Establishment and characterization of matched immortalized human frontal and occipital scalp dermal papilla cell lines from androgenetic alopecia

Androgenetic alopecia (AGA), also known as male pattern baldness, is a common hair loss condition influenced by genetic and hormonal factors. Variations in gene expression and androgen responsiveness have been observed between the frontal and occipital regions of AGA patients. However, obtaining and cultivating frontal hair follicles is challenging. Therefore, no matched frontal and occipital dermal papilla (DP) cell lines have been reported yet. This study aimed to establish matched immortalized human frontal and occipital scalp DP cell lines from AGA patients. Simian virus 40 large T antigen (SV40T-Ag) and human telomerase reverse transcriptase (hTERT) were introduced into primary human DP cells. The obtained cell lines were characterized by assessing their gene expression patterns, androgen receptor (AR) levels, and the presence of 5-alpha reductase (5αR). Additionally, we examined their response to dihydrotestosterone (DHT) and evaluated cell viability. The conditioned medium from the frontal DP cell line inhibited human hair follicle growth, leading to reduced keratinocyte proliferation and increased apoptosis. Furthermore, when the cells were cultured in a 3D environment mimicking in vivo conditions, the 3D cultured frontal DP cell line exhibited weaker sphere aggregation than the occipital DP cell line due to the increased expression of matrix metalloproteinase 1 (MMP1), MMP3, and MMP9. Additionally, the expression of DP signature genes was inhibited in the 3D cultured frontal DP cell line. These matched frontal and occipital DP cell lines hold significant potential as valuable resources for research on hair loss. Their establishment allows us to investigate the differences between frontal and occipital DP cells, contributing to a better understanding of the molecular mechanisms underlying AGA. Furthermore, these cell lines may be valuable for developing targeted therapeutic approaches for hair loss conditions.

Global Research Status and Trends in Hair Follicle Stem Cells: a Bibliometric Analysis

BACKGROUND

Hair follicle stem cells (HFSCs) are derived from the bulge region and are important autologous stem cell sources. Bibliometric is a statistical method that quantitatively analyses the research papers concerned about one special topic. This study aims to estimate the research status and trends of HFSCs worldwide by bibliometric analyses.

METHODS

Data were obtained from the Web of Science by searching keywords related to HFSCs. Publication distributions stratified by countries/regions, institutions, journals, and authors were systematically assessed. The frequency of keywords was assessed, and bibliometric mapping was employed to describe the development of HFSC research.

RESULTS

A total of 458 publications that met our screening criteria were included in this study, consisting of 423 (92.4%) articles and 35 (7.6%) reviews. The United States of America (USA) ranked first in the number of publications at 146 (31.9%), followed by China at 130 (28.4%), which is consistent with the rank of the H-index. Author keywords were classified into three clusters, namely, basic study, applied study, and biomarker; average publication time of keywords in applied study cluster is later than basic study cluster. The keywords "bulge", "nestin", and "skin" are the top three most frequent keywords in basic studies; "differentiation", "proliferation", and "alopecia" are the top three most frequent keywords in applied studies. With respect to the latest research hotspots, "apoptosis" and "tissue engineering" are relatively new keywords.

CONCLUSIONS

The USA and China were the most productive countries for research on HFSCs. The focus of keywords gradually shifted from basic study to applied study. Research on the differentiation/proliferation of HFSCs and the role of HFSCs in alopecia have been recent research focuses. Apoptosis and tissue engineering are recommended as promising research hotspots. Our study provides profound insights into the research history, current status, and future trend of HFSCs.

MicroRNA-149-mediated MAPK1/ERK2 Suppression Attenuates Hair Follicle stem Cell Differentiation

Hair follicle stem cells (HFSCs) are responsible for hair growth and hair follicle (HF) regeneration. microRNAs (miRNAs) have been demonstrated to be involved in the differentiation of HFSCs. Thus, present study aimed to explore the potential role of miR-149 in the differentiation of HFSCs. The isolated HFSCs were identified by flow cytometric sorting. miR-149 expression was determined during differentiation of HFSCs. Gain- and loss-of-function approaches were conducted to explore the roles of miR-149, MAPK1/ERK2, and FGF2/c-MYC in colony formation and proliferation of HFSCs. Furthermore, in vivo assays were undertaken in miR-149 knockout mice to confirm their roles in HFSC differentiation. miR-149 was found to be down-regulated during HFSC differentiation, and overexpressed miR-149 restricted the proliferation and differentiation of HFSCs. miR-149 was confirmed to target and inhibit MAPK1/ERK2, which was highly expressed in and positively associated with HFSC differentiation. The MAPK1/ERK2 promotion in HFSC differentiation was achieved by augmenting expression of FGF2 and c-MYC. The in vitro effects of miR-149 were validated in in vivo experiments. Taken together, up-regulated miR-149 restricted HFSC differentiation and hair growth by targeting MAPK1/ERK2 to reduce expression of FGF2 and c-MYC, which sheds light on the underlying molecular mechanism on hair growth.

Reconstruction of Large Cervicofacial Defects With Expanded Island Superficial Temporal Artery Flaps and an 810-nm Diode Laser Hair Removal Technique

BACKGROUND

Extensive cervicofacial reconstruction is challenging for plastic surgeons. Because of the location of the adjacent scalp flap nourished by the superficial temporal artery (STA), it can be a candidate for cervicofacial reconstruction.

OBJECTIVES

This article aims to report a combined treatment of an expanded island STA flap and an 810-nm diode laser hair removal technique for extensive cervicofacial defects.

METHODS

Between January 2015 and December 2018, 10 patients with lower face and neck scar contraction were reconstructed with a bilateral or unilateral expanded STA island flap and an 810-nm diode laser for hair removal in this retrospective study. Hair removal via the 810-nm laser was started when the injected volume reached the volume of the expander, with a fluence of 35 to 40 J/cm2 and a 1 to 2 Hz repetition rate. Before second-stage surgery, the hair reduction rate was assessed. Twelve months after surgery, the degree of epilation efficacy according to the satisfaction scale and Global Aesthetic Improvement Scale was evaluated.

RESULTS

This study included 2 single-pedicle flaps and 8 double-pedicle flaps. The average size of the implanted expanders was 600 mL. The average injected volume was 1405 mL. Before second surgery, there was a 67.4% hair reduction rate. Twelve months after surgery, the results of Global Aesthetic Improvement Scale were very good (3), good (6), average (1), and poor (0).

CONCLUSIONS

The expanded island STA flap and 810-nm diode laser technique may be a novel treatment option for severe face and neck aesthetic reconstruction.

A functional extracellular matrix biomaterial enriched with VEGFA and bFGF as vehicle of human umbilical cord mesenchymal stem cells in skin wound healing

The construction of microvascular network is one of the greatest challenges for tissue engineering and cell therapy. Endothelial cells are essential for the construction of network of blood vessels. However, their application meets challenges in clinic due to the limited resource of autologous endothelium. Mesenchymal stem cells can effectively promote the angiogenesis in ischemic tissues for their abilities of endothelial differentiation and paracrine, and abundant sources. Extracellular matrix (ECM) has been widely used as an ideal biomaterial to mimic cellular microenvironment for tissue engineering due to its merits of neutrality, good biocompatibility, degradability, and controllability. In this study, a functional cell derived ECM biomaterial enriched with VEGFA and bFGF by expressing the collagen-binding domain fused factor genes in host cells was prepared. This material could induce endothelial differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs) and promote angiogenesis, which may improve the healing effect of skin injury. Our research not only provides a functional ECM material to inducing angiogenesis by inducing endothelial differentiation of hUCMSCs, but also shed light on the ubiquitous approaches to endow ECM materials different functions by enriching different factors. This study will benefit tissue engineering and regenerative medicine researches.

Hair Follicle Stem Cells for Tissue Regeneration

With the positive outcomes of various cell therapies currently under pre-clinical and clinical studies, there is a significant interest in novel stem cell sources with unique therapeutic properties. Studies over the past two decades or so demonstrated the feasibility to isolate multipotent/pluripotent stem cells from hair follicles. The easy accessibility, high proliferation and differentiation ability as well as lack of ethical concerns associated with this stem cell source make hair follicle stem cells (HFSCs) attractive candidate for cell therapy and tissue engineering. This review discusses the various stem cell types identified in rodent and human hair follicles and ongoing studies on the potential use of HFSCs for skin, bone, cardio-vascular, and nerve tissue engineering.

Design of a biofluid-absorbing bioactive sandwich-structured Zn-Si bioceramic composite wound dressing for hair follicle regeneration and skin burn wound healing

The deep burn skin injures usually severely damage the dermis with the loss of hair follicle loss, which are difficult to regenerate. Furthermore, severe burns often accompanied with large amount of wound exudates making the wound moist, easily infected, and difficult to heal. Therefore, it is of great clinical significance to develop wound dressings to remove wound exudates and promote hair follicle regeneration. In this study, a sandwich-structured wound dressing (SWD) with Janus membrane property was fabricated by hot compression molding using hydrophilic zinc silicate bioceramics (Hardystonite, ZnCS) and hydrophobic polylactic acid (PLA). This unique organic/inorganic Janus membrane structure revealed excellent exudate absorption property and effectively created a dry wound environment. Meanwhile, the incorporation of ZnCS bioceramic particles endowed the dressing with the bioactivity to promote hair follicle regeneration and wound healing through the release of Zn2+ and SiO3 2- ions, and this bioactivity of the wound dressing is mainly attributed to the synergistic effect of Zn2+ and SiO3 2- to promote the recruitment, viability, and differentiation of hair follicle cells. Our study demonstrates that the utilization of the Janus membrane and synergistic effect of different type bioactive ions are effective approaches for the design of wound dressings for burn wound healing.

Comparative characterization and osteogenic / adipogenic differentiation of mesenchymal stem cells derived from male rat hair follicles and bone marrow

Clinical applications of cell therapy and tissue regeneration under different conditions need a multiplicity of adult stem cell sources. Up to date, little is available on the comparative isolation, characterization, proliferation, rapid amplification, and osteogenic/adipogenic differentiation of rat mesenchymal stem cells (MSCs) isolated from living bulge cells of the hair follicle (HF) and bone marrow (BM) from the same animal. This work hopes to use HF-MSCs as an additional adult stem cell source for research and application. After reaching 80% confluence, the cell counting, viability %, and yields of HF-MSCs and BM-MSCs were nearly similar. The viability % was 91.41 ± 2.98 and 93.11 ± 3.06 while the cells yield of initial seeding was 33.15 ± 2.76 and 34.22 ± 3.99 and of second passage was 28.76 ± 1.01 and 29.56 ± 3.11 for HF-MSCs and BM-MSCs respectively. Clusters of differentiation (CDs) analysis revealed that HF-MSCs were positively expressed CD34, CD73 and CD200 and negatively expressed CD45. BM-MSCs were positively expressed CD73 and CD200 and negatively expressed of CD34 and CD45. The proliferation of HF-MSCs and BM-MSCs was determined by means of incorporation of Brd-U, population doubling time (PDT) assays and the quantity of formazan release. The percentage of Brd-U positive cells and PDT were relatively similar in both types of cells. The proliferation, as expressed by the quantity of formazan assay in confluent cells, revealed that the quantity of release by BM-MSCs was slightly higher than HF-MSCs. Adipogenic differentiated BM-MSCs showed moderate accumulation of oil red-O stained lipid droplets when compared to that of HF-MSCs which exhibited high stain. The total lipid concentration was significantly higher in adipogenic differentiated HF-MSCs than BM-MSCs (P < 0.05). It was found that activity of bone alkaline phosphatase and calcium concentration were significantly higher (P < 0.01 and P < 0.05 respectively) in osteogenic differentiated BM-MSCs than that of HF-MSCs. The present findings demonstrate that the HF-MSCs are very similar in most tested characteristics to BM-MSCs with the exception of differentiation. Additionally; no issues have been reported during the collection of HF-MSCs. Therefore, the HF may represent a suitable and accessible source for adult stem cells and can be considered an ideal cell source for adipogenesis research.

A crucial role of fibroblast growth factor 2 in the differentiation of hair follicle stem cells toward endothelial cells in a STAT5-dependent manner

Fibroblast growth factor (FGF2) is reported to affect the proliferation, differentiation, and survival abilities of stem cells. In this study, we hypothesize that FGF2 might promote the differentiation of hair follicle stem cell (HFSCs) into endothelial cells (ECs), in a manner dependent on STAT5 activation. We first treated human HFSCs with recombinant human FGF2 to determine the involvement of FGF2 in the differentiation of HFSCs. Then the expression of EC-specific markers including von Willebrand factor (vWF), VE-cadherin, CD31, FLT-1, KDR and Tie2 was evaluated using immunofluorescence and flow cytometry, while the expression of HFSC-specific markers such as K15, K19, Lgr5, Sox9 and Lhx2 was determined by flow cytometry. Next, in vitro tube formation was performed to confirm the function of FGF2, and low-density lipoprotein (LDL) uptake by ECs and HFSCs was studied by Dil-acetylated LDL assay. In addition, we transduced FGF2-treated HFSCs with constitutive-active or dominant-negative STAT5A adenovirus vectors. FGF2 up-regulated the expression of EC-specific markers, and promoted the differentiation of HFSCs into ECs, tube formation and LDL uptake. The phosphorylated STAT5 was translocated into the nucleus of HFSCs after FGF2 treatment, but this translocation was blocked by the dominant-negative STAT5A mutant. FGF2 increased the differentiation potential through the activation of STAT5 in vivo. Taken together, we find that FGF2 promotes the differentiation of HFSCs into ECs via activated STAT5, which gives a new perspective on the role of FGF2 in the development of ischemic vascular disease.

Effects of Hair Follicle Stem Cells on Partial-Thickness Burn Wound Healing and Tensile Strength

Background:

The recent improvements in wound healing have led to new strategies in regenerative medicine. Burn wound healing is an important issue in skin regeneration and has multiple indications for stem cell therapy. HFSCs are a highly promising source of stem cells for healing use, as these cells are accessible, active and pluripotent adult stem cells.

Methods:

HFSCs of the rat whisker were isolated, cultured, and labeled with DiI. Flow cytometry method was used to detect special markers of HFSCs. Deep partial-thickness burn wound was created, and labeled HFSCs were injected around the wound bed. Wound closure was recorded via digital photographs. The inflicted rats were sacrificed at 3, 7, or 14 days post burn and used for subsequent histological and tensiometry analysis.

Results:

Our results indicated that HFSCs were positive for Nestin and CD34 markers, but negative for Kr15. Morphological and histological photographs revealed that wound closure rate was accelerated in stem cell-treated group compared with other groups. In addition, faster re-epithelialization and collagen deposition were observed. The immunohistochemical analysis suggested that CD31 expression and vascular density enhanced in the stem cell-treated group. Further, tissue tensile strength increased in HFSCs-treated rats in comparison to the control group.

Conclusion:

The present study demonstrates that HFSCs could accelerate burn wound healing as well as tensile strength in rats.

Up-regulated lncRNA5322 elevates MAPK1 to enhance proliferation of hair follicle stem cells as a ceRNA of microRNA-19b-3p

Hair follicle stem cells (HFSCs), located in the bulge region of the follicle, maintain hair follicle growth and cycling. Long non-coding RNAs (lncRNAs), non-protein coding transcripts, are widely known to play critical roles in differentiation and proliferation of stem cells. Therefore, the current study aimed to explore the regulatory roles of lncRNA5322 in HFSCs proliferation and the underlying regulatory mechanisms. Initially, the expression patterns of lncRNA5322 and microRNA-19b-3p (miR-19b-3p) in HFSCs were detected. Subsequently, gain-and loss-of-functions analyses were conducted to explore the roles of lncRNA5322, miR-19b-3p and mitogen-activated protein kinase 1 (MAPK1) in cell proliferation, colony formation and apoptosis of HFSCs, with the expression of cyclin-dependent kinase (CDK)1 and CDK2 examined. Also, the interaction relationships among lncRNA5322, miR-19b-3p and MAPK1 were explored. Furthermore, a mouse model was established to detect the roles of lncRNA5322, miR-19b-3p, and MAPK1 in wound contraction and epidermal regeneration. Over-expressed lncRNA5322 was found to promote proliferation, colony formation ability but inhibit apoptosis of HFSCs, in addition to up-regulation of the expression of CDK1 and CDK2. LncRNA5322 was found to act as a ceRNA of miR-19b-3p which directly targeted MAPK1. Furthermore, up-regulation of lncRNA5322 enhanced wound contraction and epidermal regeneration in vivo by increasing the expression of MAPK1 through functioning as a ceRNA of miR-19b-3p. In summary, the results in this study suggested that lncRNA5322 serves as a ceRNA of miR-19b-3p to elevate the expression of MAPK1, ultimately promoting HFSCs proliferation, wound contraction and epidermal regeneration of mouse model.

Are hair follicle stem cells promising candidates for wound healing?

INTRODUCTION

With the continued focus on in-depth investigations of hair follicle stem cells (HFSCs), the role of HFSCs in wound healing has attracted increasing attention from researchers. This review may afford meaningful implications for HFSC treatment of wounds.

AREAS COVERED

We present the properties of HFSCs, analyze the possibility of HFSCs in wound healing, and sum up the recent studies into wound repair with HFSCs. The details of HFSCs in wound healing have been discussed. The possible mechanisms of wound healing with HFSCs have been elaborated. Additionally, the factors that influence HFSCs in wound healing are also summarized.

EXPERT OPINION

Hair follicle stem cells are promising sources for wound healing. However, a further understanding of human HFSCs and the safety use of HFSCs in clinical practice still remain in relative infancy.

Efficient Differentiation of Bone Marrow Mesenchymal Stem Cells into Endothelial Cells in Vitro

OBJECTIVE

Endothelial cells (ECs) play an important role in neovascularisation, but are too limited in number for adequate therapeutic applications. Mesenchymal stem cells (MSCs) have the potential to differentiate into endothelial lineage cells, which makes them attractive candidates for therapeutic angiogenesis. The aim of this study was to investigate efficient differentiation of MSCs into ECs by inducing medium in vitro.

METHODS

MSCs were isolated from bone marrow by density gradient centrifugation. The characterisation of the MSCs was determined by their cluster of differentiation (CD) marker profile. Inducing medium containing vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), insulin like growth factor (IGF), epidermal growth factor (EGF), ascorbic acid, and heparin was applied to differentiate the MSCs into ECs. Endothelial differentiation was quantitatively evaluated using flow cytometry. Real time quantitative PCR (qRT-PCR) was used to analyse mRNA expression of endothelial markers. Tube formation assay was further performed to examine the functional status of the differentiated MSCs.

RESULTS

Flow cytometry analysis demonstrated that CD31⁺ and CD34⁺ cells increased steadily from 12% at 3 days, to 40% at 7 days, and to 60% at 14 days. Immunofluorescence staining further confirmed the expression of CD31 and CD34. qRT-PCR showed that expression of von Willebrand factor (vWF), vascular endothelial cadherin (VE-cadherin) and vascular endothelial growth factor receptor-2 (VEGFR-2) were significantly higher in the induced MSCs group compared with the uninduced MSCs group. The functional behavior of the differentiated cells was tested by tube formation assay in vitro on matrigel. Induced MSCs were capable of developing capillary networks, and progressive formation of vessel like structures was associated with increased EC population.

CONCLUSIONS

These results provide a method to efficiently promote differentiation of MSCs into ECs in vitro for potential application in the treatment of peripheral arterial disease.

LncRNA PlncRNA‑1 regulates proliferation and differentiation of hair follicle stem cells through TGF‑β1‑mediated Wnt/β‑catenin signal pathway

The present study demonstrated that hair follicle stem cells (HFSc) have multidirectional differentiation potential and participate in skin wound healing processes. Long non‑coding RNAs (lncRNAs) are defined as non‑protein coding transcripts longer than 200 nucleotides, which are important in the proliferation and differentiation of cells. The purpose of the present study was to investigate the role of PlncRNA‑1 in the proliferation and differentiation of HFSc. Results revealed that PlncRNA‑1, transforming growth factor (TGF)‑β1, Wnt and β‑catenin expression levels were significantly downregulated in HFSc. PlncRNA‑1 transfection promoted proliferation and differentiation of HFSc. TGF‑β1, Wnt and β‑catenin expression levels were upregulated in HFSc following transfection of PlncRNA‑1. Results demonstrated that TGF‑β1 inhibitor LY2109761 blocked proliferation and differentiation of HFSc promoted by PlncRNA‑1 transfection. In addition, TGF‑β1 inhibitor LY2109761 led to decreased Wnt and β‑catenin expression levels in HFSc. Furthermore, PlncRNA‑1 transfection stimulated the cell cycle of HFSc, whereas TGF‑β1 inhibitor LY2109761 inhibited the cell cycle of HFSc and decreased the acceleration of the cell cycle induced by PlncRNA‑1 transfection. In conclusion, these findings suggest that PlncRNA‑1 may promote proliferation and differentiation of HFSc through upregulation of TGF‑β1‑mediated Wnt/β‑catenin signaling pathway.

VEGF165 induces differentiation of hair follicle stem cells into endothelial cells and plays a role in in vivo angiogenesis

Within the vascular endothelial growth factor (VEGF) family of five subtypes, VEGF165 secreted by endothelial cells has been identified to be the most active and widely distributed factor that plays a vital role in courses of angiogenesis, vascularization and mesenchymal cell differentiation. Hair follicle stem cells (HFSCs) can be harvested from the bulge region of the outer root sheath of the hair follicle and are adult stem cells that have multi-directional differentiation potential. Although the research on differentiation of stem cells (such as fat stem cells and bone marrow mesenchymal stem cells) to the endothelial cells has been extensive, but the various mechanisms and functional forms are unclear. In particular, study on HFSCs' directional differentiation into vascular endothelial cells using VEGF165 has not been reported. In this study, VEGF165 was used as induction factor to induce the differentiation from HFSCs into vascular endothelial cells, and the results showed that Notch signalling pathway might affect the differentiation efficiency of vascular endothelial cells. In addition, the in vivo transplantation experiment provided that HFSCs could promote angiogenesis, and the main function is to accelerate host-derived neovascularization. Therefore, HFSCs could be considered as an ideal cell source for vascular tissue engineering and cell transplantation in the treatment of ischaemic diseases.

Advanced Properties of Urine Derived Stem Cells Compared to Adipose Tissue Derived Stem Cells in Terms of Cell Proliferation, Immune Modulation and Multi Differentiation

Adipose tissue stem cells (ADSCs) would be an attractive autologous cell source. However, ADSCs require invasive procedures, and has potential complications. Recently, urine stem cells (USCs) have been proposed as an alternative stem cell source. In this study, we compared USCs and ADSCs collected from the same patients on stem cell characteristics and capacity to differentiate into various cell lineages to provide a useful guideline for selecting the appropriate type of cell source for use in clinical application. The urine samples were collected via urethral catheterization, and adipose tissue was obtained from subcutaneous fat tissue during elective laparoscopic kidney surgery from the same patient (n = 10). Both cells were plated for primary culture. Cell proliferation, colony formation, cell surface markers, immune modulation, chromosome stability and multi-lineage differentiation were analyzed for each USCs and ADSCs at cell passage 3, 5, and 7. USCs showed high cell proliferation rate, enhanced colony forming ability, strong positive for stem cell markers expression, high efficiency for inhibition of immune cell activation compared to ADSCs at cell passage 3, 5, and 7. In chromosome stability analysis, both cells showed normal karyotype through all passages. In analysis of multi-lineage capability, USCs showed higher myogenic, neurogenic, and endogenic differentiation rate, and lower osteogenic, adipogenic, and chondrogenic differentiation rate compared to ADSCs. Therefore, we expect that USC can be an alternative autologous stem cell source for muscle, neuron and endothelial tissue reconstruction instead of ADSCs.

Advanced glycation end products induce glomerular endothelial cell hyperpermeability by upregulating matrix metalloproteinase activity

The present study aimed to investigate the effects of advanced glycation end‑products (AGEs) on the permeability of glomerular endothelial cells (GEnCs) and determine whether enhanced permeability was due to degradation of tight junction (TJ) complexes by matrix metalloproteinases (MMPs). Cultured monolayers of GEnCs were exposed to AGEs at different doses and treatment durations in the presence or absence of the organic MMP‑2/9 inhibitor (2R)‑2‑((4‑biphenyl sulfony‑l)amino)‑3‑phenylproprionic acid) (BiPs). Expression of the TJ proteins occludin and claudin‑5 was determined by western blot analysis and immunofluorescence, while the permeability of the GEnCs was measured using transendothelial electrical resistance and by diffusion of 4 kDa fluorescein isothiocyanate (FITC)‑dextran. The activities of MMP‑2 and MMP‑9 were assayed using gelatin zymography. The results indicated that AGE‑treated cultures significantly reduced occludin and claudin‑5 immunoreactivity. Similarly, the surface expression of these proteins was significantly reduced and rows of TJs which normally connect endothelial cells became discontinuous or fractured following AGE exposure. Disruption of TJs was accompanied by significantly reduced transendothelial resistance and hyperpermeability to FITC‑dextran. Treatment with AGEs evoked a dose‑ and time‑dependent upregulation of MMP‑2 and MMP‑9. However, co‑administration of AGEs and BiPS, an inhibitor of MMP‑2/MMP‑9, inhibited the downregulation of occludin and claudin‑5, with a concomitant reversal of GEnC monolayer hyperpermeability. In conclusion, AGEs promoted glomerular hyperpermeability in vitro by the MMP‑mediated disruption of TJs. Chronic elevation of endothelial cell AGEs in diabetes mellitus may contribute to glomerular hyperpermeability by inducing the overexpression of MMPs, which degrade TJs, leading to proteinuria.

Gelatin-chondroitin-6-sulfate-hyaluronic acid scaffold seeded with vascular endothelial growth factor 165 modified hair follicle stem cells as a three-dimensional skin substitute

INTRODUCTION

In the field of skin tissue engineering, gelatin-chondroitin-6-sulfate-hyaluronic acid (Gel-C6S-HA) stents are a suitable bio skin substitute. The purpose was to investigate the effect of genetically-modified hair follicle stem cells (HFSCs), combined with Gel-C6S-HA scaffolds, on the vascularization of tissue-engineered skin.

METHODS

Three-dimensional (3D) Gel-C6S-HA scaffolds were prepared by freeze-drying. Vascular endothelial growth factor (VEGF) 165 gene-modified rat HFSCs (rHFSCs) were inoculated into the scaffolds and cultured for 7 days. Two bilateral full-thickness skin defects were created on the back of 18 Sprague-Dawley rats. Rats were randomly divided into four groups: Group A, HFSCs transduced with VEGF165 seeded onto Gel-C6S-HA scaffolds; Group B, HFSCs transduced with empty vector seeded onto Gel-C6S-HA scaffolds; Group C, Gel-C6S-HA scaffold only; Group D, Vaseline gauze dressing. These compositions were implanted onto the defects and harvested at 7, 14 and 21 days. Wound healing was assessed and compared among groups according to hematoxylin-eosin staining, CD31 expression, alpha smooth muscle actin (α-SMA) and major histocompatibility complex class I (MHC-I) immunohistochemistry, and microvessel density (MVD) count, to evaluate the new blood vessels.

RESULTS

SEM revealed the Gel-C6S-HA scaffold was spongy and 3D, with an average pore diameter of 133.23 ± 43.36 μm. Cells seeded on scaffolds showed good adherent growth after 7 days culture. No significant difference in rHFSC morphology, adherence and proliferative capacity was found before and after transfection (P >0.05). After 14 and 21 days, the highest rate of wound healing was observed in Group A (P <0.05). Histological and immunological examination showed that after 21 days, MVD also reached a maximum in Group A (P <0.05). Therefore, the number of new blood vessels formed within the skin substitutes was greatest in Group A, followed by Group B. In Group C, only trace amounts of mature subcutaneous blood vessels were observed, and few subcutaneous tissue cells migrated into the scaffolds.

CONCLUSIONS

Tissue-engineered skin constructs, using 3D Gel-C6S-HA scaffolds seeded with VEGF165-modified rHFSCs, resulted in promotion of angiogenesis during wound healing and facilitation of vascularization in skin substitutes. This may be a novel approach for tissue-engineered skin substitutes.

Phenotypic and proteomic characteristics of human dental pulp derived mesenchymal stem cells from a natal, an exfoliated deciduous, and an impacted third molar tooth

The level of heterogeneity among the isolated stem cells makes them less valuable for clinical use. The purpose of this study was to understand the level of heterogeneity among human dental pulp derived mesenchymal stem cells by using basic cell biology and proteomic approaches. The cells were isolated from a natal (NDPSCs), an exfoliated deciduous (stem cells from human exfoliated deciduous (SHED)), and an impacted third molar (DPSCs) tooth of three different donors. All three stem cells displayed similar features related to morphology, proliferation rates, expression of various cell surface markers, and differentiation potentials into adipocytes, osteocytes, and chondrocytes. Furthermore, using 2DE approach coupled with MALDI-TOF/TOF, we have generated a common 2DE profile for all three stem cells. We found that 62.3 ± 7% of the protein spots were conserved among the three mesenchymal stem cell lines. Sixty-one of these conserved spots were identified by MALDI-TOF/TOF analysis. Classification of the identified proteins based on biological function revealed that structurally important proteins and proteins that are involved in protein folding machinery are predominantly expressed by all three stem cell lines. Some of these proteins may hold importance in understanding specific properties of human dental pulp derived mesenchymal stem cells.