Differentiation of mesenchymal stem cells to germ‐like cells under induction of Sertoli cell‐conditioned medium and retinoic acid

The aim of this research was to find a way to differentiate germ cells from umbilical cord Wharton's jelly mesenchymal stem cells (MSCs) to support in vitro spermatogenesis. A small piece of Wharton's jelly was cultured in high‐glucose Dulbecco's modified Eagle's medium in present of 10% foetal calf serum. After the fourth passage, the cells were isolated and cultured in Sertoli cell‐conditioned medium under induction of two different doses of retinoic acid (10^?5, 10^?6 m ). The differentiation of MSC to germ‐like cells was evaluated by expression of Oct4, Nanog, Plzf, Stra8 and Prm1 genes during different days of culture through qPCR. The results showed that there were downregulation of Oct4 and Nanog and upregulation of pre‐meiotic germ cell marker (stra8) and haploid cell marker (Prm1) when MSCs are differentiated over time. The expression of Bax gene (an apoptotic marker) was significantly observed in high dosage of retinoic acid (RA). As a result, RA has positive effects on proliferation and differentiation of MSCs, but its effects are related to dosage. The success of this method can introduce umbilical cord MSC as a source of germ cells for treatment of infertility in future.     

Comparison of the efficacy of three concentrations of retinoic acid for transdifferentiation induction in sheep marrow‐derived mesenchymal stem cells into male germ cells

Recent studies have shown the unique role of retinoic acid (RA) in the induction of transdifferentiation in mesenchymal stem cells (MSCs) into germ cells (GCs). This study is the first study that compares the efficacy of three different concentrations of RA for the production of male GCs in vitro. Male sheep marrow‐derived MSCs (MMSCs) were treated with the following concentrations of RA: 1 μm (RA1), 5 μm (RA2) and 10 μm (RA3) for a period of 21 days. The production of male GCs was evaluated by the assessment of expressions of GC‐specific markers (by RT‐PCR, qRT‐PCR and immunocytochemistry), morphological characteristics and changes in alkaline phosphatase (ALP) activity. All three concentrations created male GC features. RA treatment upregulated the expressions of VASA and beta1 INTEGRIN and downregulated PIWIL2 and OCT4. DAZL was not expressed by RA treatment. Interestingly, immunocytochemistry detected PGP 9.5 expression in all treatment groups, with the highest expression noted in the RA3 group (P < 0.05). GC‐like cells along with increased ALP activity were observed in all treated cultures, too. Finally, results showed that 10 μm RA has the most efficiency for transdifferentiation induction in MMSCs and production of male GCs in vitro.     

Germ cell differentiation of bone marrow mesenchymal stem cells

Bone marrow mesenchymal stem cells (BM‐MSCs) were first cultured under induction of retinoic acid (RA), Sertoli cells conditioned medium and RA + con (conditioned medium) as treatment groups. The presence of Sertoli cells was confirmed by immunocytochemistry of follicle‐stimulating hormone receptor in Sertoli cells and flow cytometry by anti‐Gata4 antibody. Cell viability and morphology of nucleus and cytoplasm of BM‐MSCs were evaluated by MTT test and DAPI staining respectively. The expression of Oct4, Plzf, Scp3, Caspases 8, 9 and 3 genes was evaluated by RT‐PCR. For increasing the accuracy of experiment, the expression of Vasa and SCP3 genes was investigated quantitatively by real‐time PCR after 0, 5, 10, 15 days of culture. The results showed that the number of apoptotic cells increased in RA group. The expression of apoptosis genes (Caspases 3, 8 and 9) was also observed in this group all days of culture. Measurement of Vasa and Scp3 genes by RT‐PCR confirmed the positive effects of retinoic acid on increasing of genes expression. So, in this study, a group with maximum expression of differentiation genes and minimum expression of apoptotic genes was RA + conditioned medium group. DNA fragmentation was not observed in all groups.     

Retinoic acid and 17β-estradiol improve male germ cell differentiation from mouse-induced pluripotent stem cells

This research aimed to explore the impacts of retinoic acid (RA)/17β-estradiol (E) induction and embryoid body formation to enhance differentiation of mouse-induced pluripotent stem cells (miPSCs) into male germ cells in vitro. Flow cytometry and qPCR were conducted to describe miPSCs differentiation process. Various temporal expression profiles of germ cell-related genes were traced. Stra8 gene expression increased in the RA group on the 4th day compared to other groups. The RA group experienced a more significant increase than E group. The expression of Sycp3 increased in RA + E group on 4th day compared with other groups. Expression of AKAP3 enhanced in the RA + E group than other groups on day 4. Moreover, miPSCs showed that this gene expression in the RA + E group was increased in comparison to RA and E groups on day 7. AKAP3 gene expression on day 7 of miPSCs decreased in RA and E groups. Flow cytometry data indicated that 3%–8% of the cells in sub-G1 stage were haploid after RA and E induction compared to other groups on day 4. This study showed that miPSCs possess the power for differentiating into male germ cells in vitro via formation of embryoid body by RA with/or E induction.     

Secretions released from mesenchymal stem cells improve spermatogenesis restoration of cytotoxic treatment with busulfan in azoospermia mice

This study aimed at the efficacy of sequential treatment of bone marrow-derived mesenchymal stem cell secretion for busulfan-treated azoospermia in mice. The conditioned media (CM) was obtained from bone marrow mesenchymal stem cells (MSCs) or 293 cells. Chemically induced azoospermia mice received 200 μl MSC-CM or 293-CM twice a week intravenously for three consecutive weeks. The histological assessment of spermatogenic recovery quantifying the expression of meiosis-associated genes, and Sertoli cell barrier functional factors were assessed. The characteristics of TM4 cells (Sertoli cell line) after pre-incubation of MSC-CM in vitro were also obtained. The MSC-CM group had the most spermatogenic colonies among the three groups (p < .05), but no spermatids were seen. Expressions of the meiosis-associated genes Dazl, Vasa, Miwi, Stra8, CyclinA1, Pgk2 and Scp3 in MSC-CM testis were remarkably higher compared with 293-CM and busulfan groups respectively (p < .05). The levels of Sertoli cell barrier functional factors, for example ICAM-1 and N-cadherin, were significantly increased during MSC-CM treatment (p < .05). Moreover, pre-incubation of MSC-CM particularly accelerated the CD54 (ICAM-1) and CD44 expressions of TM4 cells and promoted cell inherent adhesion. MSC-CM treatment can significantly improve the short-term restoration of spermatogonial structures of chemically induced azoospermia related to facilitating Sertoli cell adhesion integrity.     

Physiological testosterone levels enhance chondrogenic extracellular matrix synthesis by male intervertebral disc cells in vitro,but not by mesenchymal stem cells

Background contextTestosterone (T) is a hormone and regulator involved in the processes of development of the organism (ie, promoting development of bone and muscle mass). Although T effects on the mesenchyme-derived muscle, bone, and adipose tissues are well studied, T effects on intervertebral disc (IVD) have not been reported.PurposeThe aim was to test the following hypothesis: if a physiological concentration of T (～30 nM) can improve in vitro chondrogenesis of human IVD cells and mesenchymal stem cells (MSCs).Study design/settingHuman IVD cells and MSCs were differentiated to chondrogenic lineage on gelatin scaffolds for 4 weeks, in the presence or absence of T.MethodsChondrogenesis was assessed by cell viability, by measuring gene expression with quantitative polymerase chain reaction and extracellular matrix (ECM) accumulation with immunoblotting, immunohistochemical, and biochemical methods.ResultsSupplementation of T to chondrogenic culture did not affect viability. In male IVD cells, T had a beneficial impact on chondrogenesis, particularly in nucleus pulposus cells, demonstrated by an increased expression of aggrecan, collagen type I, and especially collagen type II. Conversely, T had no effects on chondrogenesis of female IVD cells or MSCs from both genders. A gene expression array of transforming growth factor β/bone morphogenetic protein signaling cascade showed that in male IVD cells, T promoted a stable general but nonsignificant increase in gene expression. Furthermore, aromatase inhibitor anastrazole repressed the effect of T on ECM expression by IVD cells. The results suggest that T increased ECM accumulation in male IVD cells in combination with its conversion to estradiol by the enzyme aromatase.ConclusionsWe demonstrated that T effectively enhances in vitro chondrogenesis in male IVD cells, rising the interest in the possible role of sex hormones in IVD degeneration. Nevertheless, T does not affect chondrogenic differentiation of female IVD cells and MSCs from both genders.     

Therapeutic implications of mesenchymal stem cells transfected with hepatocyte growth factor transplanted in rat kidney with unilateral ureteral obstruction

Purpose

The purpose of the study was to establish whether bone marrow mesenchymal stem cells (MSCs) transfected with hepatocyte growth factor (HGF) can migrate and localize in the rat's kidney with unilateral ureteral obstruction (UUO) and contribute to repair of renal fibrosis.

Methods

We separated and cultured bone marrow-derived MSCs of male rats in vitro and transfected them with adenovirus-mediated HGF (Ad-HGF). The expression of HGF was measured with enzyme-linked immunosorbent assay. Sixty female rats were sham operated (n = 24) or subjected to left UUO: Ad-HGF-transfected MSCs, uninfected MSCs, or saline was injected into the rat's tail vein. Kidney tissue was collected at the end of the seventh or 14th day after operation. The distribution of Y chromosome in the kidney after Ad-HGF-transfected MSCs transplantation was determined by an in situ hybridization method. As the hallmark of myofibroblasts, α-smooth muscle actin (expression of which significantly increases in the presence of renal fibrosis) was detected by immunohistochemistry in all UUO rats' left kidney tissue.

Results

Y chromosome-positive cells were found only in the obstructed kidney of the transplantation group. The positive cells were mainly distributed in the tubular cells. The average intensity of immunolabeling for α-smooth muscle actin in the transplanted group significantly decreased compared with sham-transplanted group (P < .05), and the expression in the rats injected with uninfected MSCs was higher than that in the rats with MSCs transfected with HGF (P < .05).

Conclusions

Mesenchymal stem cells transfected with HGF can migrate to the rat kidney with UUO and are mainly distributed in the region of renal tubular epithelial cells. The data indicate that MSCs transfected with HGF contribute to a reduction of renal fibrosis after ureteral obstruction and suggest that this may be exploited therapeutically.     

Mesenchymal stem cells attenuate liver fibrosis by suppressing Th17 cells – an experimental study

This study investigates molecular and cellular mechanisms involved in mesenchymal stem cell (MSC)‐mediated modulation of IL‐17 signaling during liver fibrosis. Mice received CCl₄ (1 μl/g intraperitoneally) twice/week for 1 month. MSCs (1 × 10⁶), or MSC‐conditioned medium (MSC‐CM), were intravenously injected 24 h after CCl₄ and on every 7th day. Liver fibrosis was determined by macroscopic examination, histological analysis, Sirius red staining, and RT‐PCR. Serum levels of cytokines, indoleamine 2,3‐dioxygenase (IDO), and kynurenine were determined by ELISA. Flow cytometry was performed to identify liver‐infiltrated cells. In vitro, CD4⁺ T cells were stimulated and cultured with MSCs. 1‐methyltryptophan was used for inhibition of IDO. MSCs significantly attenuated CCl₄‐induced liver fibrosis by decreasing serum levels of inflammatory IL‐17, increasing immunosuppressive IL‐10, IDO, and kynurenine, reducing number of IL‐17 producing Th17 cells, and increasing percentage of CD4⁺IL‐10⁺ T cells. Injection of MSC‐CM resulted with attenuated fibrosis accompanied with the reduced number of Th17 cells in the liver and decreased serum levels of IL‐17. MSC‐CM promoted expansion of CD4⁺FoxP3⁺IL‐10⁺ T regulatory cells and suppressed proliferation of Th17 cells. This phenomenon was completely abrogated in the presence of IDO inhibitor. MSCs, in IDO‐dependent manner, suppress liver Th17 cells which lead to the attenuation of liver fibrosis.     

Bone marrow derived mesenchymal stromal cells provide survival signals to B-cells in vitro – no major role for BAFF

BackgroundMesenchymal stromal cells (MSCs) are a unique cell type that has strong anti-proliferative effects on co-cultured activated T and B-cells in vitro. Based on our observation of significant differences between rheumatoid arthritis (RA) and osteoarthritis (OA) bone marrow B-cell compartments, we hypothesized that RA bone marrow MSCs may contribute to the pathogenesis of RA by enhancing B-cell survival.ObjectivesTo compare the effect of RA and OA bone marrow derived MSCs (RA-MSCs, OA-MSCs) on the survival of healthy donor purified B-cells.MethodsRA-MSCs (n=7) and OA-MSCs (n=5) were isolated from patients undergoing hip replacement surgery, and cultured in vitro for 2-5 passages. Washed cells were co-cultured with CD20+ B-cells for 60 hours in 17 different co-culture experiments. Cell survival was analyzed using 7-amino-actinomycin D (7AAD) labelling and flow-cytometric analysis and compared to the survival of B-cells cultured without MSCs (n=8). Expression of B-cell activating factor (BAFF) mRNA and protein was determined by RT-PCR and flow-cytomery after labelling with BAFF-specific antibodies.ResultsWe observed that the presence of both RA-MSCs and OA-MSCs in the cultures significantly enhanced B-cell survival (70,11±7,28% and 54,65±11,83% viable cells, respectively) as compared to controls (35,13±13,83%, p < 0,001, Kruskal-Wallis ANOVA), the effect being more prominent in RA-MSCs (p < 0,05, Tukey-Kramer test). Both RA-MSCs and OA-MSCc displayed expression of BAFF mRNA and protein. We did not observe a convincing enhancement of BAFF mRNA expression by TNF-α. Blocking BAFF signalling by specific BAFF and BAFF-R antibodies, reduced the survival of B-cells by 20%, but did not abrogate the positive effect of MSCs on B-cell survival.ConclusionsMSC interaction with B-cells may provide additional stimuli for lymphocyte survival via an as yet unidentified factor and therefore contribute to the pathogenesis of RA. BAFF, though produced by MSCs, is of minor importance in this setting. Further studies to identify the molecular basis of our observation are warranted.     

Bioengineered Cartilage in a Scaffold‐Free Method by Human Cartilage‐Derived Progenitor Cells: A Comparison With Human Adipose‐Derived Mesenchymal Stromal Cells

The objective of our study was to investigate chondrogenesis potential of human adipose‐derived mesenchymal stromal cells (MSCs), using as a positive control a human source of cartilage‐derived progenitor cells (PCs). This source of PCs was recently described by our group and dwells on the surface of nasoseptal cartilage. Histological analysis using Safranin O staining and immunofluorescence for actin filaments and collagen type II was performed on three‐dimensional (3D) pellet cultures. Cartilage PCs and adipose MSCs showed similarities in monolayer culture related to cell morphology and proliferation. Our 3D pellet cultures substantially reduced the actin stress and after 21 days under chondrogenic medium, we observed an increase in the pellet diameter for cartilage PCs (7.4%) and adipose MSCs (21.2%). Adipose‐derived MSCs responded to chondrogenic stimulus, as seen by positive areas for collagen type II, but they were not able to recreate a mature extracellular matrix. Using semi‐quantitative analysis, we observed a majority of Safranin O areas rising from blue (no stain) to orange (moderate staining) and no changes in fibroblastic morphology (P < 0.0001). For cartilage PCs, chondrogenic induction is responsible for morphological changes and a high percentage of matrix area/number of cells (P ≤ 0.0001), evaluated by computerized histomorphometry. Morphological analyses reveal that adipose‐derived MSCs were not able to recreate a bioengineered cartilage. The cost of culture was reduced, as the cartilage PCs under growth‐factor free medium exhibit a high score for cartilage formation compared with the induced adipose mesenchymal stromal cells (P = 0.0021). Using a pellet 3D culture, our cartilage PCs were able to produce a cartilage tissue in vitro, leading to the future development of bioengineered products.     

Direct effects of simvastatin on proliferation and matrix accumulation in cultured murine mesangial cells

Background. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors have been demonstrated to suppress glomerular injuries in various renal diseases. However, it is not fully clear whether HMG-CoA reductase inhibitors directly regulate matrix protein accumulation in mesangial cells. Methods. We investigated the effect of simvastatin (SIM), an HMG-CoA reductase inhibitor, on DNA synthesis in cultured murine mesangial cells stimulated by fetal calf serum (FCS). We then determined whether SIM affected the expression of regulatory factors of cell growth and matrix protein accumulation, using Northern analysis. Results. SIM dose-dependently inhibited FCS-induced DNA synthesis after 24 h of incubation. SIM treatment for 24 h suppressed the mRNA expression of platelet-derived growth factor (PDGF)-B chain, PDGF receptor β-subunit and c-myc, while the expression of transforming growth factor β (TGF-β) was not affected. Concerning matrix protein synthesis, the mRNA expression of type IV collagen was suppressed, whereas that of type III collagen was markedly upregulated. As for matrix turnover proteins, SIM had a markedly suppressive effect on the mRNA expression of plasminogen activator inhibitor-1 (PAI-1), with a constant expression of tissue-type plasminogen activator (tPA). Conclusions. These results indicate that SIM may sup-press mesangial cell proliferation in part through the downregulation of PDGF, PDGF-receptor, and c-myc mRNA expressions. In addition, the suppression of the synthesis of collagen IV and PAI-1 appears to be a direct inhibitory effect of SIM on glomerular matrix accumulation. Received: November 13, 2000 / Accepted: December 14, 2000     

Endothelial differentiation of diabetic adipose-derived stem cells

Background

Diabetic (DM) patients frequently lack autologous vascular tissue required for revascularization procedures and dialysis access creation. We have developed a tissue-engineered graft that uses adipose-derived stem cells (ASC) as endothelial cell substitutes. Here, we compare DM versus nondiabetic (NDM) ASC in terms of isolation efficiency, proliferation, commitment toward endothelial lineage, and seeding onto the luminal surface of a graft.

Methods

ASC were isolated from liposuction specimens of vascular surgery patients. Proliferation was assessed by constructing growth curves over 14 d. ASC were differentiated in endothelial growth medium (EGM2). Endothelial commitment was assessed by measuring endothelial cell-specific gene expression (CD31, von Willebrand factor) and by cord formation on Matrigel. Finally, ASC were seeded onto a vascular scaffold, flow conditioned, and imaged with confocal microscopy.

Results

Diabetes did not alter ASC isolation efficiency (224,028 ± 20,231 cells/g adipose for DM (n = 53) versus 259,345 ± 15,441 cells/g adipose for NDM (n = 145; P = 0.21). Growth curves for DM (n = 6) and NDM (n = 6) also appeared similar. After culture in EGM2, upregulation of CD31 and von Willebrand factor message was observed in NDM; these markers were found within the primary cultures of DM but no upregulation was observed after culture in EGM2. Both groups exhibited similar cord formation on Matrigel and retention to vascular scaffolds.

Conclusions

Isolation and proliferation studies suggest that adipose is a promising source of stem cells for tissue engineering in the DM population. The angiogenic potential of DM ASC appears intact; however, differences in acquisition of endothelial cell markers suggest that differentiation may be inhibited or delayed by diabetes.     

Hypoxia promotes proliferation and osteogenic differentiation potentials of human mesenchymal stem cells

Mesenchymal stem cells (MSCs), which can be isolated from bone marrow and other somatic tissues, are residing in an environment with relative low oxygen tension. The purpose of this study is to investigate the effects of hypoxia on MSCs, and we hypothesize that oxygen concentration regulates the intricate balance between cellular proliferation and commitment towards differentiation. In this study, human bone marrow‐derived MSCs were cultured under hypoxia with 1% O₂. The proliferation ability of MSCs was increased after a 7‐day hypoxic culture period. Migration assay showed that hypoxia enhanced the migration capabilities of MSCs. Moreover, expression of stemness genes Oct4, Nanog, Sall4 and Klf4 was increased under hypoxia. Furthermore, the differentiation ability of MSCs under hypoxia favored osteogenesis while adipogenesis was inhibited during a 4‐week induction period. Cytokine antibody array analysis showed that a number of growth factors were up‐regulated after a 7‐day hypoxic incubation and the differential expression of growth factors may account for the increased proliferation and osteogenic potentials of MSCs under hypoxic condition. Taken together, hypoxia provides a favorable culture condition to promote proliferation as well as osteogenesis of MSCs through differential growth factor production. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:260–266, 2012     

LPS-pretreatment adipose-derived mesenchymal stromal cells promote wound healing in diabetic rats by improving angiogenesis

Mesenchymal stem cells (MSCs) play a key role in wound healing, and the advantages of pretreated MSCs in wound healing have previously been reported. In the present study, we investigated the impact of LPS pretreated human adipose-derived MSCs on skin wound healing in diabetic rats. We found that some improvements occurred through improving angiogenesis. Then, we scrutinized the impact of lipopolysaccharide (LPS) treatment on human adipose-derived MSCs in a high-glucose (HG) medium, as an in vitro diabetic model. In vivo findings revealed significant improvements in epithelialization and angiogenesis of diabetic wounds which received LPS pre-MSCs. Particularly, LPS pre-MSCs-treated diabetic wounds reached considerably higher percentages of wound closure. Also, the granulation tissue of these wounds had higher pronounced epithelialization and more vascularization compared with PBS-treated and MSCs-treated diabetic ones by CD31, VEGF, CD90, collagen 1, and collagen 3 immunostaining. Western-blots analyses indicated that LPS pre-MSCs led to the upregulation of vascular endothelial growth factor (VEGF) and DNMT1. In addition, significantly higher cell viability (proliferation/colonie), and elevated VEGF and DNMT1 protein expression were observed when MSCs were treated with LPS (10 ng/ml, 6 h) in HG culture media. Based on these findings, it is suggested that LPS pre-MSCs could promote wound repair and skin regeneration, in some major processes, via the improvement of cellular behaviors of MSCs in the diabetic microenvironment. The beneficial advantages of LPS treated with mesenchymal stem cells on wound healing may lead to establishing a novel approach as an alternative therapeutic procedure to cure chronic wounds in diabetic conditions.     

Human mesenchymal stem cell co-culture modulates the immunological properties of human intervertebral disc tissue fragments in vitro

The capacity of mesenchymal stem cells (MSCs) to differentiate into intervertebral disc (IVD)-like cells has been well described, but their ability to modulate the inflammatory processes in the IVD remains unclear. We found that tissue obtained by discectomy of degenerated and post-traumatic IVD contains significant amounts of IgG antibodies, a sign of lymphocyte infiltration. Further we investigated whether MSCs in vitro, which were characterized for their multilineage differentiation potential and may have immunomodulatory effects on IVD fragments. IVD fragments were co-cultured in contact with peripheral blood lymphocytes (PBLs) and MSCs, and as functional controls we used contact co-cultures of PBLs stimulated with pokeweed mitogen (2.5 μg/mL) and MSCs. The time course of lymphocyte proliferation (Alamar Blue), IgG (ELISA) and gene expression (RT-PCR) of anti-inflammatory cytokines (TGF-β1, IL-10) by MSCs and pro-inflammatory molecules (IL-1α, IL-1β and TNF-α) by the IVD fragments were analyzed. Depending on the response to the presence of MSCs, the IVD fragments (n = 13) were divided in two groups: responders (n = 9), where inflammation was inhibited by MSCs and non-responders (n = 4), where MSCs did not decrease inflammation. At 1 week in co-culture, MSCs reduced significantly the IgG production in the IVD responders group to 69% and PBLs proliferation to 57% of the control. MSCs expression of the anti-inflammatory TGF-β1 increased with time, while IL-10 was expressed only at day 1. IVD gene expression of TNF-α decreased constantly, whereas IL-1α and IL-1β expression increased. In conclusion, these data suggest that MSCs may modulate disc-specific inflammatory and pain status and aid regeneration of the host tissue.     

大鼠骨髓间充质干细胞诱导分化为表皮细胞的实验观察

目的:研究表皮生长因子(Epidermal growth factor,EGF)加条件培养基体外诱导大鼠 MSCs 向表皮细胞定向分化的可行性。方法:采用 Ficoll-Paque 淋巴细胞分离液分离扩增大鼠骨髓 MSCs,免疫细胞化学染色及流式细胞仪进行鉴定。传至第3代的大鼠 MSCs 用表皮生长因子(EGF)、条件培养基等定向诱导 MSCs 分化为表皮细胞;免疫细胞化学对细胞角蛋白 CK5/8、19(Cytokeratin5/8、19)阳性表达细胞进行检测。结果:从大鼠骨髓中分离培养的 MSCs 增殖能力强,细胞表面标志 CD34、CD45阴性,CD29、CD44阳性,流式细胞仪检测显示细胞纯度高,诱导后7d 细胞免疫化学显示角蛋白5/8、19染色阳性,具有表皮细胞特征。结论:从大鼠骨髓中分离培养出的问充质干细胞,具有自我更新和增殖能力强的特点,经诱导可定向分化表达角蛋白。     

Intracellular calcium concentration of corpus cavernosum smooth muscle cells is decreased by the overexpression of PnNOS gene in adipose tissue‐derived stem cells

The study investigated the effects of adipose tissue‐derived stem cells (ADSCs) modified with penile neuronal nitric oxide synthase (PnNOS) gene on intracellular calcium concentration in rat corpus cavernosum smooth muscle cells (CCSMCs). ADSCs and CCSMCs of Sprague–Dawley (SD) rats were isolated and cultured in vitro respectively. The rat PnNOS gene was transferred into the ADSCs mediated by a recombinant adenovirus vector. The expression of the PnNOS gene was detected. At the same time, the concentration of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) was assayed. After coculturing with the CCSMCs of SD rats, which were isolated and expanded ex vivo, the cGMP and NO levels of ADSCs and CCSMCs were measured. Intracellular calcium concentration ([Ca²⁺]_i) in rat CCSMCs was measured with Fluo‐3/AM by flow cytometer after cocultured with ADSCs overexpressing PnNOS gene. The mRNA and protein expression of PnNOS gene mediated by recombinant adenovirus vector significantly overexpressed and lasted at least 2 weeks. Meanwhile, the concentration of NO and cGMP in ADSCs was greatly increased. The concentration of cGMP was significantly increased, and [Ca²⁺]_i was obviously decreased in CCSMCs compared with the control groups (P < 0.05) after cocultured with ADSCs for 3 days. These findings demonstrated that ADSCs overexpressing PnNOS gene might decrease [Ca²⁺]i in CCSMCs by up‐regulating NO–cGMP signalling pathway.     

Development and characterization of novel clinical grade neonatal porcine bone marrow‐derived mesenchymal stem cells

Due to recent advances in research on mesenchymal stem cells (MSCs), MSCs are expected to be used in various clinical applications. However, securing adequate cadaveric donors and safety of living donors are major issues. To solve such issues, we have examined to develop clinical grade neonatal porcine bone marrow‐derived MSCs (npBM‐MSCs). Clinical grade neonatal porcine bone marrow cells were collected, frozen, and sent to our laboratory by air. The npBM‐MSCs were isolated from thawed bone marrow cells, then frozen. The thawed npBM‐MSCs were examined for CD markers and differentiated into chondrocytes, osteocytes, and adipocytes. They were compared with human bone marrow‐derived MSCs (hBM‐MSCs) for growth rate and size. To assess the robustness of proliferation, we compared culture medium with or without gelatin. The npBM‐MSCs expressed positive MSC markers CD29, CD44, and CD90 and were differentiated into chondrocytes, osteocytes, and adipocytes. The doubling time of npBM‐MSCs was significantly shorter than that of hBM‐MSCs (17.3 ± 0.8 vs 62.0 ± 19.6 hours, P < 0.01). The size of npBM‐MSCs was also significantly smaller than that of hBM‐MSCs (13.1 ± 0.3 vs 17.5 ± 0.4 μm, P < 0.001). The npBM‐MSCs showed similar proliferation characters irrespective of with or without gelatin coating. The npBM‐MSCs secreted VEGF‐A, VEGF‐C, and TGF‐β1. We have established npBM‐MSCs which show super‐rapid growth, small size, and robust proliferation profile. The np‐MSCs might be able to solve the donor issues for MSC therapy.     

脐带间充质干细胞增强无精子症模型睾丸特异性基因表达

在生殖男科领域，探索人脐带间充质干细胞（HUCMSCs）对无精子症的治疗作用。HUCMSCs具有潜在的免疫抑制功能，并能够分泌多种细胞因子和生长因子，因此具有潜在的临床应用价值。作为探索，我们移植HUCMSCs进入无精子症小鼠睾丸间质，检测是否能够促进精子发生过程。从不同来源的脐带中分离HUCMSCs，移植进入白消安处理的小鼠睾丸间质中，采用注射生理盐水和HEK293细胞作为对照，对侧睾丸不注射。三周之后，RT-PCR检测10个生殖细胞特异性表达的基因，并检N3个特异性蛋白的表达。结果表明，注射人脐带间充质干细胞之后的表达明显高于对照组，证实生殖细胞特异性基因的表达上调，从而表明HUCMSCs对睾丸生精功能的恢复具有促进作用，为治疗无精子症探索一条新的途径。     

Application of mesenchymal stromal cells in urological diseases

The application of stem cells and their use in tissue‐engineering approaches is emerging in clinical therapeutic intervention strategies. The use of adult stem cells, either autologous or allogenic, does not raise ethical concerns, in contrast to embryonic stem cells. Mesenchymal stromal cells (MSCs) can be easily obtained from bone marrow or from adipose tissue and further expanded in vitro. Due to their differentiation capacity, MSCs are very attractive for tissue engineering purposes. Furthermore, MSCs secrete a variety of mediators that have beneficial effects on the regenerating tissue. In this review we give an insight into stem cell hierarchy, define the properties of MSCs and summarize recent reports of their administration in urological diseases.