Enrichment of putative human epidermal stem cells based on cell size and collagen type IV adhesiveness

人的表皮的干细胞(EpSCs ) 的丰富和鉴定具有为基本研究和临床的申请的首要的重要性。尽管为 EpSCs 的丰富的几条途径被建立了，充实可行 EpSCs 的一张纯人口仍然是一项挑战性的任务。一条改进途径值得发展提高 EpSCs 的纯净和生存能力。这里，我们报导那种房间尺寸与骨胶原类型 IV 粘着性结合了能在一条改进途径被使用充实纯、可行的人的 EpSCs。我们分开了很快支持者 keratinocytes 进从 5-7 microm (人口 A )在尺寸 的三张人口到 7-9 microm (人口 B )，到>或在直径的 =9 microm (人口 C )，并且发现人的通常认为的 EpSCs 能进一步与最小的尺寸在人口 A 被充实。在三张人口之中，人口 A 显示了 beta1-integrin 受体的最高的密度，在 G0/G1 阶段包含了房间的最高的百分比，显示出最高的原子核到细胞质比率，并且拥有了最高的殖民地形成效率(CFE ) 。当注入了鼠科的胚囊时，这些房间参予了多织物形成。与根据 beta1-integrin 抗体染色排序通常认为的 EpSCs 的一条以前的途径相比，更显著地， EpSCs 的生存能力由改进途径充实显著地被提高。我们的结果为人的 EpSCs 的丰富提供通常认为的策略，并且在干细胞生物学鼓励进一步的学习进房间尺寸的角色。

Expression of vascular endo-thelial growth factor in rat uterus during peri-implantation

The first distinct mark of rodent implantation is the increased vascular permeability and significant angio-genesis at the sites of blastocyst implantation, but its mechanism is not clearly defined. Vascular endothelial growth factor (VEGF) is the key mediator for angiogenesis during em-bryogenesis and adult span and also serves as a vascular permeability factor. The aim of this study is to explore VEGF regulation mechanism and the possible role that VEGF plays in implantation by studying the VEGF expression and angiogenesis in the rat uterus during estrous cycle, ovarioec-tomized and peri-implantation stages using in situ message RNA hybridization and confocal laser scanning techniques. The results indicated that VEGF was regulated by ovarian steroid hormones. VEGF expression before implantation was localized at luminal epithelium, shifted to stroma as implantation initiated and extensively located at the decidualizing stroma region after implantation. Bandeiraea simplicifolia-1 (BS-1) agglutinin and

Role of αVβ3 integrin in embryo implantation in the mouse

Integrin, a heterodimeric adhesive molecule composed of a and (5 subunits, can regulate cell adhesion and trafficking. Recent data have documented that, at the 'implantation window' stage, aVp3 integrin participates in the maternal-fetal interaction and becomes a potential marker of uterine receptivity. Furthermore, it can affect invasiveness of embryo. This work made a further study about its action mechanism. Results of indirect immunofluorescence and laser scanning confocal microscopy showed that αVβ3 integrin was clearly expressed in the mouse blastocyst. Injection of αVβS integrin antiserum into a uterine horn of a pregnant mouse on day 3 markedly decreased the number of embryos implanted (P 【 0.001). In a co-culture model, aVp3 integrin antisera at 1 : 100 and 1 : 200 dilutions significantly depressed the attachment and outgrowth reactions of blastocysts on monolayer of uterine epithelial cells. Analysis of correlation manifested that the inhibitory effect of αVβ3 integrin antiserum was

Effect of fibronectin and leukaemia inhibitory factor on matrix metalloproteinases in mouse blastocyst

This study was designed to detect the effects of fibronectin (FN) and leukaemia inhibitory factor (LIF) on matrix metallopoteinases (MMPs) of mouse blastocysts. The experiments comprised four groups: first, blastocysts grew on the dishes with FN-coated; the second, without FN-coated; the third group, without FN coated, but with 20 ng/μL LIF added to culture medium; and the fourth group, with both FN-coated and 20 ng/μL LIF added. Using MMP-2 and MMP-9 primers respectively, the expressions of MMP-2 and MMP-9 were detected by RT-PCR and cloning identification. The results showed that in the first group, MMP-2 and MMP-9 were produced after 12 and 24 h culturing; in the third group, there were both MMP-2 and MMP-9 bands when blastocysts were cultured for 24 h; and in the fourth group, MMP-2 and MMP-9 bands appeared when blastocysts were cultured for 6, 12 and 24 h. But in the second group no MMP-2 or MMP-9 band appeared. These results show that FN may initiate the transcription of MMP-2 and MMP-9 genes

mTOR signaling promotes stem cell activation via counterbalancing BMP-mediated suppression during hair regeneration

Hair follicles(HFs)undergo cycles of degeneration(catagen),rest(telogen),and regeneration(anagen)phases.Anagen begins when the hair follicle stem cells(HFSCs)obtain sufficient activation cues to overcome suppressive signals,mainly the BMP pathway,from their niche cells.Here,we unveil that mTOR complex 1(mTORC1)signaling is activated in HFSCs,which coincides with the HFSC activation at the telogen-to-anagen transition.By using both an inducible conditional gene targeting strategy and a pharmacological inhibition method to ablate or inhibit mTOR signaling in adult skin epithelium before anagen initiation,we demonstrate that HFs that cannot respond to mTOR signaling display significantly delayed HFSC activation and extended telogen.Unexpectedly,BMP signaling activity is dramatically prolonged in mTOR signaling-deficient HFs.Through both gain-and loss-of-function studies in vitro,we show that mTORC1 signaling negatively affects BMP signaling,which serves as a main mechanism whereby mTORC1 signaling facilitates HFSC activation.Indeed,in vivo suppression of BMP by its antagonist Noggin rescues the HFSC activation defect in mTORC1-null skin.Our findings reveal a critical role for mTOR signaling in regulating stem cell activation through counterbalancing BMP-mediated repression during hair regeneration.

The expression and function of VEGF at embryo implantation "window" in the mouse

Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen that plays a critical role in angiogenesis. Recent reports indicated that VEGF was closely involved in embryo implantation and embryonic vasculogenesis. However, very little information is available about the detailed expression and function of VEGF at implantation 'window'. In this work, VEGFs were primarily present on uterine epithelial cell monolayer and blasto-cysts including the outgrew trophoblasts at implantation window. VEGF antibodies decreased the number of mice embryos implanted and the percentage of blastocysts with attachment and outgrowth in a co-culture model in a dose-dependant manner. These findings demonstrate that VEGF is one of the essential cytokines for embryo implantation in mouse. VEGF may act as a local mediator to regulate the maternal-fetal interaction, and facilitate blastocyst implantation.

Interfamily pregnancy and expression of CD57, CD68 in deciduas between golden hamster and mouse

Pregnancy between different species is one of the key steps to interspecific somatic cell cloning. Although interspecific clone embryos have been constructed, they could not develop to birth after being transferred to recipi-ents. In order to clarify the mechanism of this phenomenon, interfamily pregnancy between golden hamste (Mesocricetus auratus) and mouse (Mus musculus) was studied. Co-culture results indicated that the adhesion ratios of golden hamster blastocysts on mouse uterine epithelia monolayer 12, 24, 48 and 72 h after co-culture were all significantly lower than those of mouse blastocysts. The outgrowth ratios of golden hamster blastocysts on mouse uterine epithelia monolayer 48, 72 h after co-culture were both significantly lower than those of mouse blastocysts (P < 0.01). Golden hamster抯 blastula could be implanted and develop to D 11 of pregnancy after being transferred to mouse uterus (the 7th day after embryo transfer). Compared to the transfer of mouse embryo to mouse uterus, the successful ratio of interfamily embryo transfer was lower and the bulk of fetus was smaller than that of intraspecific fetus. Compared to intraspecific preg-nancy of mouse, the remote decidual tissue of interfamily pregnancy on D8 is looser. At the same time, expressions of CD57 and CD 68 in remote deciduas were both higher than those in the secondary deciduas in both intraspecific and interfamily pregnancy. However, expressions of the two molecules in interfamily pregnancy were lower than those in intraspecific pregnancy. These results showed that interfam-ily pregnancy could be established between golden hamster and mouse. But the development of fetus in interfamily pregnancy was slower than that in intraspecific pregnancy. The expression difference of CD57 and CD68 indicates the difference of immunoreaction between interfamily and in-traspecific pregnancy, which may be one of the reasons lead-ing to interfamily pregnancy termination.

Advances in interspecific pregnancy

Interspecific pregnancy in which the conceptus and female carrying the pregnancy are of different species is a key step to interspecific cloning. Cloning endangered animals by interspecific pregnancy is such a highlight catching people’s eyes nowadays. In this article, the history of interspecific pregnancy, the methods for establishment of interspecific pregnancy, the corresponding theories, barriers and applied prospects are reviewed.

BET bromodomain inhibitor JQ1 regulates spermatid development by changing chromatin conformation in mouse spermatogenesis

As a BET bromodomain inhibitor, JQ1 has been proven have efficacy against a number of different cancers. In terms of male reproduction, JQ1 may be used as a new type of contraceptive, since JQ1 treatment in male mice could lead to germ cell defects and a decrease of sperm motility, moreover, this effect is reversible. However, the mechanism of JQ1 acting on gene regulation in spermatogenesis remains unclear. Here, we performed single-cell RNA sequencing (scRNA-seq) on mouse testes treated with JQ1 or vehicle control to determine the transcriptional regulatory function of JQ1 in spermatogenesis at the single cell resolution. We confirmed that JQ1 treatment could increase the numbers of somatic cells and spermatocytes and decrease the numbers of spermatid cells. Gene Ontology (GO) analysis demonstrated that differentially expressed genes which were down-regulated after JQ1 injection were mainly enriched in “DNA conformation change” biological process in early developmental germ cells and “spermatid development” biological process in spermatid cells. ATAC-seq data further confirmed that JQ1 injection could change the open state of chromatin. In addition, JQ1 could change the numbers of accessible meiotic DNA double-stranded break sites and the types of transcription factor motif that functioned in pachytene spermatocytes and round spermatids. The multi-omics analysis revealed that JQ1 had the ability to regulate gene transcription by changing chromatin conformation in mouse spermatogenesis, which would potentiate the availability of JQ1 in male contraceptive.

Advances in stem cell research

In 1998, biologists Thomson and Gearhart successfully derived stem cells from human embryos. One year later, several researchers discovered that adult stem cells still retain the ability to be differentiated into unrelated types of cells. Advances in stem cell research open a promising direction for applied medical science. Moreover, it may also force scientists to reconsider the fundamental theory about how cells grow up. Stem cell research was considered by Science as the top of the ten breakthroughs of science of the year[1]. This paper gives a survey of recent advances in stem cell research.

Cooperation-based sperm clusters mediate sperm oviduct entry and fertilization

Dear Editor,Sperm cooperation has been observed in multiple species(Pizzari and Foster,2008),yet its existenee and benefit for reproductive success in mammals remains underexplored.Here,combining tissue-clearing with deep three-dimensional(3D)imagi ng,we dem on strate that postcopulatory mouse sperm congregate into unidirectional sperm cooperative clusters at the utero-tubal junction(UTJ),a key physical barrier for passage into the oviduct.

Effects of blocking Le^Y oligosaccharide on cell surface to MMPs secreted by blastocysts and epithelial cells in mouse in vitro

In order to understand the role of Le+Y oligosaccharide antigen (Le+Y) during implantation, the relationship of Le+Y on the cell surface with matrix metalloproteinase (MMPs) secreted by blastocysts and monolayer epithelial cells during implantation in the mouse %in vitro% was studied by monoclonal antibody (mAb) AH-6, directed to Le+Y[Fuc α1-2 Gal β1-4 (Fuc α1-3) GlcNAc-], and gelatin zymography. The results showed that MMPs secretion was reduced after Le+Y on the cell surface of either epithelial cells or trophoblasts was blocked. It indicated that MMPs expression which played an important function during the process of implantation were regulated by Le+Y. Therefore, it was considered that Le+Y could regulate embryos invasion by some mechanism.