אנו מודים ל Douay ו MC Giarratana (אוניברסיטת פריס VI, צרפת) עצה על בידול vivo erythroid לשעבר, אלן ד &#39;וה&#39; אטקינס (OHRI, קנדה) למתן דגימות דם (שהושג לפי מחקר החולים אוטווה אתיקה עמוד # 2007804-01H), ד Trono (אקול פוליטכניק הפדרלי דה לוזאן) עבור מתן וקטורים lentiviral ו FJ דילוורת&#39; (OHRI, קנדה) עבור אנושות לקרוא את כתב היד. פרויקט זה מומן על ידי מענק CIHR (MOP-82813) כדי MBCGP הוא מקבל מלגת קרן מחקר אונטריו הדרכה Regulomics חישובית דוקטורים. MB הקתדרה למחקר בקנדה בתקנה של ביטוי גנים.

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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=amplification+and+characterization+of+a+population+of+human+erythroid+progenitors.">amplification and characterization of a population of human erythroid progenitors.</a> Br J Haematol. 106, 912-922 (1999).</li><li>Malik, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+in+vitro+model+of+human+red+blood+cell+production+from+hematopoietic+progenitor+cells.">An in vitro model of human red blood cell production from hematopoietic progenitor cells.</a> Blood. 91, 2664-2671 (1998).</li><li>Carlile, G. W., Smith, D. H., Wiedmann, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Caspase-3+has+a+nonapoptotic+function+in+erythroid+maturation.">Caspase-3 has a nonapoptotic function in erythroid maturation.</a> Blood. 103, 4310-4316 (2004).</li><li>Mazurier, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+analysis+and+efficient+selection+of+human+transduced+primitive+hematopoietic+cells+using+the+humanized+S65T+green+fluorescent+protein.">Rapid analysis and efficient selection of human transduced primitive hematopoietic cells using the humanized S65T green fluorescent protein.</a> Gene Ther. 5, 556-562 (1998).</li><li>Salmon, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-level+transgene+expression+in+human+hematopoietic+progenitors+and+differentiated+blood+lineages+after+transduction+with+improved+lentiviral+vectors.">High-level transgene expression in human hematopoietic progenitors and differentiated blood lineages after transduction with improved lentiviral vectors.</a> Blood. 96, 3392-3398 (2000).</li></ol>

אין ניגודי אינטרסים הכריז.

מספר שיטות שימשו בעבר להבדיל תאים erythroid בתרבות עם דרגות משתנות של הצלחה. לדוגמה, כמה פרוטוקולים ללא תרבות משותפת על MS-5 מאפשרת הרחבה של תאים erythroid אך אינם יעילים בהפקת לבגרות מלאה בתאי דם אדומים enucleated 12-17. בעוד שיטות אחרות לאפשר enucleation יעיל, זה על חשבונם של התפשטות 18,19. השיטה השתמשנו כאן, שפותחה לראשונה על ידי המעבדה Douay 6, המשלבת צעד ראשון תרבות נוזלי, אשר מאריך הגברה התא במהלך השלבים המוקדמים של בידול erythroid ובכך מספק לנו מספר גדול של אבות מוקדם (הכרחי הגנומיקה ומחקרים proteomics) , ואת השלב השני של תרבות משותפת על MS-5 תאים mesenchymal, וזה חשוב על מנת למקסם את סינתזת המוגלובין להשיג enucleation מלאה של כדוריות דם אדומות. שתי מגבלות השיטה שלנו הם 1) את מידת מספיק עדיין הגברה בשלבים המוקדמים של בידול, שעד כה מנעה מאיתנו מלא לאפיין את אבות מוקדם מאוד erythroid ברמת חלבון 2) את העלות הגבוהה של ביצוע הפרוטוקול, במיוחד בקנה מידה גדול. איכות תרבות ריאגנטים התא ציטוקינים חיונית ההבחנה לשעבר erythroid vivo. יש לציין כי השימוש BIT (טבלה 2) כתחליף בסרום היא קריטית. ואכן בחוויה שלנו את השימוש BIT בוטלו אצווה ל-אצווה וריאציות שחווינו בעבר (סביר בשל ההבדלים טוהר מגיב) כאשר באמצעות מקורות נפרדים של שור אינסולין בדם, אלבומין ו transferrin. עוד נקודה קריטית היא איכות שכבת MS-5 המשמש תרבות משותפת של תאים erythroid. ואכן, MS-5 תאים יש ומחוברות 70% כאשר תאים erythroid מתווספים יש לשנות את כל 3-4 ימים. אם MS-5 תאים ומחוברות יותר מדי, התאים erythroid לא יגדל להבחין כראוי. בנוסף, לא בריא MS-5 תאים נוטים לנתק, מה שהופך את קצירת התאים erythroid קשה. שיטות הקודם השתמשו רטרווירוס למסירה, גנים גזע / ובתאים hematopoietic בתרבות. עם זאת, רטרווירוסים להדביק רק תאים מתחלקים ולכן אינם יעילים הדבקה של שקט בעיקר CD34 + תאים מבודדים דם טבורי, מח עצם או leukapheresis 20. היתרון העיקרי של גישות lentiviral עבור משלוח של גן הוא שהיא מאפשרת זיהום יעילה של תאים באופן עצמאי מעמד התרבות שלהם 7,21. משלוח lentiviral בתיווך שלנו הגן מאפשר מציאה ביעילות או יתר להביע גורמי שעתוק ספציפיים שיכולים לשנות את גורל התא. מנתח פנוטיפי המתאים (תאית ומולקולרית) יכול להיות המציאו לאחר ההדבקה לחשוף פנוטיפים בפרט. בנוסף, תנאי הגידול עשויים להשתנות לטובת מסוים התא סוגי לאחר ההדבקה. ברוח דברים אלה, בפרוטוקול זה בחרנו לא להשתמש בכל שיטה כדי לבחור lentivirus תאים הנגועים משתי סיבות עיקריות: 1) יעילות ההדבקה שלנו הוא גבוה מאוד (איור 6C) ו 2) אנו חוששים כי האמצעים שננקטו כדי לבחור lentivirus תאים הנגועים (למשל תאים מיון או אנטיביוטיקה) מוטים כלפי לשרוד / מתרבים התאים מסוגלים לבטא את הגן או עמידות לאנטיביוטיקה או את הסמן פלורסנט ברמות גבוהות ובכך מסתיר פנוטיפ אפופטוטיים פוטנציאליים.

lentiviral-mediated knockdown during ex vivo erythropoiesis of human hematopoietic stem cells

Erythropoiesis היא מערכת מודל נפוץ ללמוד התמיינות תאים. במהלך erythropoiesis, pluripotent אדם מבוגר hematopoietic בתאי גזע (HSCs) להתמיין אבות oligopotent, מבשרי מחויב ובוגרת כדוריות דם אדומות 1. תהליך זה מווסת על חלק גדול ברמה של ביטוי גנים, לפיו גורמי שעתוק ספציפיים להפעיל השושלת גנים ספציפיים במקביל תוך הדחקת גנים ספציפיים סוגי תאים אחרים 2. מחקרים על גורמי תעתוק ויסות erythropoiesis מבוצעות בדרך כלל באמצעות שורות תאים אנושיים המייצגות Murine, במידה מסוימת, תאים erythroid בשלבים נתון של בידול 3-5. שורות תאים יכולים להפוך זאת באופן חלקי בלבד לחקות תאים erythroid והכי חשוב הם לא מאפשרים אחד comprehensibly המחקר שינויים דינמיים המתרחשים התקדמות תאים בשלבים רבים לקראת גורלו הסופי erythroid שלהם. לכן, האתגר הנוכחי נותר פיתוח פרוטוקול להשיג אוכלוסיות הומוגניות יחסית של HSCs הראשי erythroid תאים בשלבים שונים של התמיינות בכמויות מספיקות כדי לבצע גנומיקה ניסויים proteomics. כאן אנו מתארים vivo לשעבר לתא תרבות פרוטוקול להשרות התמיינות erythroid מן האדם גזע / ובתאים hematopoietic שהיו מבודדים מהדם או טבורי, מח עצם או דם היקפי מבוגר מגויסת עם G-CSF (leukapheresis). מערכת זו תרבות, שפותחה לראשונה על ידי המעבדה Douay 6, משתמשת ציטוקינים ושיתוף תרבות על תאים mesenchymal לחקות את microenvironment מח עצם. שימוש בפרוטוקול לשעבר בידול vivo, אנו צופים הגברה חזקה של אבות erythroid, אינדוקציה של דיפרנציאציה אך ורק כלפי השושלת erythroid ו התבגרות להשלים לשלב enucleated כדוריות דם אדומות. לכן, מערכת זו מספקת הזדמנות ללמוד את המנגנון המולקולרי של ויסות תעתיק התקדמות בתאי גזע hematopoietic לאורך השושלת erythroid. לימוד erythropoiesis ברמה תעתיק גם דורש את היכולת גורמים ספציפיים מעל מפורשת או מציאה ב העיקרי תאים erythroid. לשם כך, אנו משתמשים lentivirus בתיווך משלוח גן מערכת המאפשרת זיהום יעיל של שניהם חלוקת ולא חלוקת תאים 7. כאן אנו מראים כי אנו מסוגלים ביעילות מציאה גורם שעתוק בתוך TAL1 העיקרי erythroid תאים אנושיים. בנוסף, ביטוי של GFP מדגים יעילות של זיהום lentiviral קרוב ל 90%. לפיכך, פרוטוקול שלנו מספק מערכת שימושית מאוד עבור אפיון של רשת רגולטורית של גורמי תעתוק כי erythropoiesis שליטה.

Watch this Scientific Journal Video about Lentiviral-mediated Knockdown During Ex Vivo Erythropoiesis of Human Hematopoietic Stem Cells at JoVE.com

Lentiviral-mediated Knockdown During Ex Vivo Erythropoiesis of Human Hematopoietic Stem Cells

<em&gt; לשעבר vivo</em&gt; פרוטוקול לייצר תאים אנושיים בוגרים הדם האדומים מתוך גזע / אבות hematopoietic מתואר. בנוסף אנו מתארים שיטה יעילה משלוח lentiviral ל מציאה גורם שעתוק בתוך TAL1 העיקרי תאים erythroid. היעילות של משלוח גן בתיווך lentivirus מודגמת באמצעות וירוסים GFP להביע.

Lentiviral בתיווך מציאה במהלך Ex Vivo Erythropoiesis של אדם בתאי גזע hematopoietic

Erythropoiesis is a commonly used model system to study cell differentiation. During erythropoiesis, pluripotent adult human hematopoietic stem cells ...

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Lentiviral-mediated Knockdown During Ex Vivo Erythropoiesis of Human Hematopoietic Stem Cells

13.0K Views.  Ottawa Hospital Research Institute.  לשעבר vivo פרוטוקול לייצר תאים אנושיים בוגרים הדם האדומים מתוך גזע / אבות hematopoietic מתואר. בנוסף אנו מתארים שיטה יעילה משלוח lentiviral ל מציאה גורם שעתוק בתוך TAL1 העיקרי תאים erythroid. היעילות של משלוח גן בתיווך lentivirus מודגמת באמצעות וירוסים GFP להביע.

Video: Lentiviral-mediated Knockdown During Ex Vivo Erythropoiesis of Human Hematopoietic Stem Cells

Isolation and Transplantation of Hematopoietic Stem Cells (HSCs)

Isolation and Transplantation of Hematopoietic Stem Cells HSCs

בידוד והשתלות של בתאי גזע hematopoietic (HSCs)

Derivation of Hematopoietic Stem Cells from Murine Embryonic Stem Cells

A stem cell is defined as a cell with the capacity to both self-renew and generate multiple differentiated progeny.  Embryonic stem cells (ESC) are derived from the blastocyst of the early embryo and are pluripotent in differentiative ability.  Their vast differentiative potential has made them the focus of much research centered on deducing how to coax them to generate clinically useful cell types.  The successful derivation of hematopoietic stem cells (HSC) from mouse ESC has recently been accomplished and can be visualized in this video protocol.  HSC, arguably the most clinically exploited cell population, are used to treat a myriad of hematopoietic malignancies and disorders.  However, many patients that might benefit from HSC therapy lack access to suitable donors.  ESC could provide an alternative source of HSC for these patients.  The following protocol establishes a baseline from which ESC-HSC can be studied and inform efforts to isolate HSC from human ESC.  In this protocol, ESC are differentiated as embryoid bodies (EBs) for 6 days in commercially available serum pre-screened for optimal hematopoietic differentiation.  EBs are then dissociated and infected with retroviral HoxB4.  Infected EB-derived cells are plated on OP9 stroma, a bone marrow stromal cell line derived from the calvaria of  M-CSF-/- mice, and co-cultured in the presence of hematopoiesis promoting cytokines for ten days.  During this co-culture, the infected cells expand greatly, resulting in the generation a heterogeneous pool of 100s of millions of cells.  These cells can then be used to rescue and reconstitute lethally irradiated mice.

This protocol details the derivation of transplantable hematopoietic stem cells from mouse embryonic stem cells (ESC) and their subsequent injection into lethally irradiated recipient mice. Briefly, ESC are differentiated as embryoid bodies, which are then infected with retroviral HoxB4 and co-cultured with OP9 stromal cells and hematopoietic cytokines.

גזירת בתאי גזע hematopoietic מ Murine בתאי גזע עובריים

A stem cell is defined as a cell with the capacity to both self-renew and generate multiple differentiated progeny.  Embryonic stem cells (ESC) are ...

In vitro and in vivo Bioluminescence Reporter Gene Imaging of Human Embryonic Stem Cells

The discovery of human embryonic stem cells (hESCs) has dramatically increased the tools available to medical scientists interested in regenerative medicine. However, direct injection of hESCs, and cells differentiated from hESCs, into living organisms has thus far been hampered by significant cell death, teratoma formation, and host immune rejection. Understanding the in vivo hESC behavior after transplantation requires novel imaging techniques to longitudinally monitor hESC localization, proliferation, and viability. Molecular imaging has given investigators a high-throughput, inexpensive, and sensitive means for tracking in vivo cell proliferation over days, weeks, and even months. This advancement has significantly increased the understanding of the spatio-temporal kinetics of hESC engraftment, proliferation, and teratoma-formation in living subjects.

A major advance in molecular imaging has been the extension of noninvasive reporter gene assays from molecular and cellular biology into in vivo multi-modality imaging platforms. These reporter genes, under control of engineered promoters and enhancers that take advantage of the host cell s transcriptional machinery, are introduced into cells using a variety of vector and non-vector methods. Once in the cell, reporter genes can be transcribed either constitutively or only under specific biological or cellular conditions, depending on the type of promoter used. Transcription and translation of reporter genes into bioactive proteins is then detected with sensitive, noninvasive instrumentation (e.g., CCD cameras) using signal-generating probes such as D-luciferin.

To avoid the need for excitatory light to track stem cells in vivo as is required for fluorescence imaging, bioluminescence reporter gene imaging systems require only an exogenously administered probe to induce light emission. Firefly luciferase, derived from the firefly Photinus pyralis, encodes an enzyme that catalyzes D-luciferin to the optically active metabolite, oxyluciferin. Optical activity can then be monitored with an external CCD camera. Stably transduced cells that carry the reporter construct within their chromosomal DNA will pass the reporter construct DNA to daughter cells, allowing for longitudinal monitoring of hESC survival and proliferation in vivo. Furthermore, because expression of the reporter gene product is required for signal generation, only viable parent and daughter cells will create bioluminescence signal; apoptotic or dead cells will not. 

In this video, the specific materials and methods needed for tracking stem cell proliferation and teratoma formation with bioluminescence imaging will be described.

With the growing interest in stem cell therapies, molecular imaging techniques are ideal for monitoring stem cell behavior after transplantation. Luciferase reporter genes have enabled non-invasive, repetitive assessment of cell survival, location, and proliferation in vivo. This video will demonstrate how to track hESC proliferation in a living mouse.

במבחנה פליטת אור הדמיה vivo ג&#39;ין הכתב של בתאי גזע עובריים אנושיים

The discovery of human embryonic stem cells (hESCs) has dramatically increased the tools available to medical scientists interested in regenerative ...

Isolation and Analysis of Hematopoietic Stem Cells from the Placenta

Hematopoietic stem cells (HSCs) have the ability to self-renew and generate all cell types of the blood lineages throughout the lifetime of an individual. All HSCs emerge during embryonic development, after which their pool size is maintained by self-renewing cell divisions. Identifying the anatomical origin of HSCs and the critical developmental events regulating the process of HSC development has been complicated as many anatomical sites participate during fetal hematopoiesis. Recently, we identified the placenta as a major hematopoietic organ where HSCs are generated and expanded in unique microenvironmental niches (Gekas, et al 2005, Rhodes, et al 2008). Consequently, the placenta is an important source of HSCs during their emergence and initial expansion.
In this article, we show dissection techniques for the isolation of murine placenta from E10.5 and E12.5 embryos, corresponding to the developmental stages of initiation of HSCs and the peak in the size of the HSC pool in the placenta, respectively. In addition, we present an optimized protocol for enzymatic and mechanical dissociation of placental tissue into single-cell suspension for use in flow cytometry or functional assays. We have found that use of collagenase for single-cell suspension of placenta gives sufficient yields of HSCs. An important factor affecting HSC yield from the placenta is the degree of mechanical dissociation prior to, and duration of, enzymatic treatment.
We also provide a protocol for the preparation of fixed-frozen placental tissue sections for the visualization of developing HSCs by immunohistochemistry in their precise cellular niches. As hematopoietic specific antigens are not preserved during preparation of paraffin embedded sections, we routinely use fixed frozen sections for localizing placental HSCs and progenitors.

We have identified the placenta as a major hematopoietic organ during development. We found that hematopoietic stem cells (HSCs) are both generated and expanded in the placenta in unique microenvironmental niches. Here, we describe experimental techniques required for isolation and visualization of HSCs in the mouse placenta.

בידוד ניתוח בתאי גזע hematopoietic מן השליה

Hematopoietic stem cells (HSCs) have the ability to self-renew and generate all cell types of the blood lineages throughout the lifetime of an individual. ...

Isolation of Early Hematopoietic Stem Cells from Murine Yolk Sac and AGM

In the mouse embryo, early hematopoiesis occurs simultaneously in multiple organs, which includes the yolk sac and aorta-gonad-mesonephros region. These regions are crucial in establishing the blood system in the embryos and leads to the eventual movement of stem cells into the fetal liver and then development of adult stem cells in the bonemarrow. Early hematopoietic stem cells can be isolated from these organs through microdissection of the embryo followed by flow cytometric sorting to obtain a more pure population. It remains unclear how these stem cell populations contribute to the fetal and adult stem cell pool.   Also, our lab investigates how early stem cells functionally differ from fetal and adult hematopoietic stem cells. Furthermore, our lab sorts different populations of hematopoietic stem cells and test their functional role in the context of a variety of genetic models. In this video, we demonstrate the micro-dissection procedure we commonly use and also show the results of a typical FACS plotfter isolating these rare populations, it is possible to perform a variety of functional assays including: colony assays and bone marrow transplants. 



This video shows how to micro-dissect the yolk sac and aorta-gonad-mesonephros region from embryos and use flow cytometry to sort hematopoietic stem cells.

בידוד מוקדם בתאי גזע hematopoietic מ Murine חלמון Sac ו AGM

In the mouse embryo, early hematopoiesis occurs simultaneously in multiple organs, which includes the yolk sac and aorta-gonad-mesonephros region. These ...

Ex Vivo Culture of Primary Human Fallopian Tube Epithelial Cells

Epithelial ovarian cancer is a leading cause of female cancer mortality in the United States. In contrast to other women-specific cancers, like breast and uterine carcinomas, where death rates have fallen in recent years, ovarian cancer cure rates have remained relatively unchanged over the past two decades 1. This is largely due to the lack of appropriate screening tools for detection of early stage disease where surgery and chemotherapy are most effective 2, 3. As a result, most patients present with advanced stage disease and diffuse abdominal involvement. This is further complicated by the fact that ovarian cancer is a heterogeneous disease with multiple histologic subtypes 4, 5. Serous ovarian carcinoma (SOC) is the most common and aggressive subtype and the form most often associated with mutations in the BRCA genes. Current experimental models in this field involve the use of cancer cell lines and mouse models to better understand the initiating genetic events and pathogenesis of disease 6, 7. Recently, the fallopian tube has emerged as a novel site for the origin of SOC, with the fallopian tube (FT) secretory epithelial cell (FTSEC) as the proposed cell of origin 8, 9. There are currently no cell lines or culture systems available to study the FT epithelium or the FTSEC. Here we describe a novel ex vivo culture system where primary human FT epithelial cells are cultured in a manner that preserves their architecture, polarity, immunophenotype, and response to physiologic and genotoxic stressors. This ex vivo model provides a useful tool for the study of SOC, allowing a better understanding of how tumors can arise from this tissue, and the mechanisms involved in tumor initiation and progression.

Ex Vivo Culture of Primary Human Fallopian Tube Epithelial Cells

The fallopian tube (FT) is emerging as an alternative site of origin for serous ovarian carcinoma (SOC). This protocol describes a novel method for the isolation and ex vivo culture of fallopian tube epithelial cells. This system recapitulates the in vivo epithelium and allows the study of SOC pathogenesis.

Ex Vivo התרבות של האדם תאים ראשוניים החצוצרה אפיתל

Epithelial ovarian cancer is a leading cause of female cancer mortality in the United States. In contrast to other women-specific cancers, like breast and ...

Phenotypic Analysis and Isolation of Murine Hematopoietic Stem Cells and Lineage-committed Progenitors

The bone marrow is the principal site where HSCs and more mature blood cells lineage progenitors reside and differentiate in an adult organism. HSCs constitute a minute cell population of pluripotent cells capable of generating all blood cell lineages for a life-time1. The molecular dissection of HSCs homeostasis in the bone marrow has important implications in hematopoiesis, oncology and regenerative medicine. We describe the labeling protocol with fluorescent antibodies and the electronic gating procedure in flow cytometry to score hematopoietic progenitor subsets and HSCs distribution in individual mice (Fig. 1). In addition, we describe a method to extensively enrich hematopoietic progenitors as well as long-term (LT) and short term (ST) reconstituting HSCs from pooled bone marrow cell suspensions by magnetic enrichment of cells expressing c-Kit. The resulting cell preparation can be used to sort selected subsets for in vitro and in vivo functional studies (Fig. 2).
Both trabecular osteoblasts2,3 and sinusoidal endothelium4 constitute functional niches supporting HSCs in the bone marrow. Several mechanisms in the osteoblastic niche, including a subset of N-cadherin+ osteoblasts3 and interaction of the receptor tyrosine kinase Tie2 expressed in HSCs with its ligand angiopoietin-15 concur in determining HSCs quiescence. "Hibernation" in the bone marrow is crucial to protect HSCs from replication and eventual exhaustion upon excessive cycling activity6. Exogenous stimuli acting on cells of the innate immune system such as Toll-like receptor ligands7 and interferon-&alpha;6 can also induce proliferation and differentiation of HSCs into lineage committed progenitors. Recently, a population of dormant mouse HSCs within the lin- c-Kit+ Sca-1+ CD150+ CD48- CD34- population has been described8. Sorting of cells based on CD34 expression from the hematopoietic progenitors-enriched cell suspension as described here allows the isolation of both quiescent self-renewing LT-HSCs and ST-HSCs9. A similar procedure based on depletion of lineage positive cells and sorting of LT-HSC with CD48 and Flk2 antibodies has been previously described10. In the present report we provide a protocol for the phenotypic characterization and ex vivo cell cycle analysis of hematopoietic progenitors, which can be useful for monitoring hematopoiesis in different physiological and pathological conditions. Moreover, we describe a FACS sorting procedure for HSCs, which can be used to define factors and mechanisms regulating their self-renewal, expansion and differentiation in cell biology and signal transduction assays as well as for transplantation.

A method to analyse the distribution of bone marrow hematopoietic progenitors in flow cytometry as well as to efficiently isolate highly purified hematopoietic stem cells (HSCs) is described. The isolation procedure is essentially based on magnetic enrichment of c-Kit+ cells and cell sorting to purify HSCs for cellular and molecular studies.

ניתוח בידוד פנוטיפי של Murine בתאי גזע hematopoietic ו-Lineage מחויבים אבות

The bone marrow is the principal site where HSCs and more mature blood cells lineage progenitors reside and differentiate in an adult organism. HSCs ...

Ex vivo Culture of Mouse Embryonic Skin and Live-imaging of Melanoblast Migration

Melanoblasts are the neural crest derived precursors of melanocytes; the cells responsible for producing the pigment in skin and hair. Melanoblasts migrate through the epidermis of the embryo where they subsequently colonize the developing hair follicles1,2. Neural crest cell migration is extensively studied in vitro but in vivo methods are still not well developed, especially in mammalian systems. One alternative is to use ex vivo organotypic culture3-6. Culture of mouse embryonic skin requires the maintenance of an air-liquid interface (ALI) across the surface of the tissue3,6. High resolution live-imaging of mouse embryonic skin has been hampered by the lack of a good method that not only maintains this ALI but also allows the culture to be inverted and therefore compatible with short working distance objective lenses and most confocal microscopes. This article describes recent improvements to a method that uses a gas permeable membrane to overcome these problems and allow high-resolution confocal imaging of embryonic skin in ex vivo culture6. By using a melanoblast specific Cre-recombinase expressing mouse line combined with the R26YFPR reporter line we are able to fluorescently label the melanoblast population within these skin cultures. The technique allows live-imaging of melanoblasts and observation of their behavior and interactions with the tissue in which they develop. Representative results are included to demonstrate the capability to live-image 6&#160;cultures in parallel.

Ex vivo Culture of Mouse Embryonic Skin and Live-imaging of Melanoblast Migration

We describe the dissection and ex vivo culture of mouse embryonic skin. The culture system maintains an air-liquid interface across the tissue surface and allows imaging on an inverted microscope. Melanoblasts, a component of the developing skin, are fluorescently labeled allowing their behavior to be observed using confocal microscopy.

אקס תרבות Vivo של עור העכבר עוברי וLive-הדמיה של הגירת Melanoblast

Melanoblasts are the neural crest derived precursors of melanocytes; the cells responsible for producing the pigment in skin and hair. Melanoblasts ...

In vivo Clonal Tracking of Hematopoietic Stem and Progenitor Cells Marked by Five Fluorescent Proteins using Confocal and Multiphoton Microscopy

We developed and validated a fluorescent marking methodology for clonal tracking of hematopoietic stem and progenitor cells (HSPCs) with high spatial and temporal resolution to study in vivo hematopoiesis using the murine bone marrow transplant experimental model. Genetic combinatorial marking using lentiviral vectors encoding fluorescent proteins (FPs) enabled cell fate mapping through advanced microscopy imaging. Vectors encoding five different FPs: Cerulean, EGFP, Venus, tdTomato, and mCherry were used to concurrently transduce HSPCs, creating a diverse palette of color marked cells. Imaging using confocal/two-photon hybrid microscopy enables simultaneous high resolution assessment of uniquely marked cells and their progeny in conjunction with structural components of the tissues. Volumetric analyses over large areas reveal that spectrally coded HSPC-derived cells can be detected non-invasively in various intact tissues, including the bone marrow (BM), for extensive periods of time following transplantation. Live studies combining video-rate multiphoton and confocal time-lapse imaging in 4D demonstrate the possibility of dynamic cellular and clonal tracking in a quantitative manner.

In vivo Clonal Tracking of Hematopoietic Stem and Progenitor Cells Marked by Five Fluorescent Proteins using Confocal and Multiphoton Microscopy

Combinatorial 5 fluorescent proteins marking of hematopoietic stem and progenitor cells allows in vivo clonal tracking via confocal and two-photon microscopy, providing insights into bone marrow hematopoietic architecture during regeneration. This method allows non-invasive fate mapping of spectrally-coded HSPCs-derived cells in intact tissues for extensive periods of time following transplantation.

במשובט מעקב vivo של גזע hematopoietic ובתאים המסומנים על ידי חמישה חלבונים ניאון באמצעות Confocal וmultiphoton מיקרוסקופית

We developed and validated a fluorescent marking methodology for clonal tracking of hematopoietic stem and progenitor cells (HSPCs) with high spatial and ...

In Vivo 4-Dimensional Tracking of Hematopoietic Stem and Progenitor Cells in Adult Mouse Calvarial Bone Marrow

Through a delicate balance between quiescence and proliferation, self renewal and production of differentiated progeny, hematopoietic stem cells (HSCs) maintain the turnover of all mature blood cell lineages. The coordination of the complex signals leading to specific HSC fates relies upon the interaction between HSCs and the intricate bone marrow microenvironment, which is still poorly understood[1-2].
We describe how by combining a newly developed specimen holder for stable animal positioning with multi-step confocal and two-photon in vivo imaging techniques, it is possible to obtain high-resolution 3D stacks containing HSPCs and their surrounding niches and to monitor them over time through multi-point time-lapse imaging. High definition imaging allows detecting ex vivo labeled hematopoietic stem and progenitor cells (HSPCs) residing within the bone marrow. Moreover, multi-point time-lapse 3D imaging, obtained with faster acquisition settings, provides accurate information about HSPC movement and the reciprocal interactions between HSPCs and stroma cells.
Tracking of HSPCs in relation to GFP positive osteoblastic cells is shown as an exemplary application of this method. This technique can be utilized to track any appropriately labeled hematopoietic or stromal cell of interest within the mouse calvarium bone marrow space.

In Vivo 4-Dimensional Tracking of Hematopoietic Stem and Progenitor Cells in Adult Mouse Calvarial Bone Marrow

The nature of the interactions between hematopoietic stem and progenitor cells (HSPCs) and bone marrow niches is poorly understood. Custom hardware modifications and a multi-step acquisition protocol allow the use of two-photon and confocal microscopy to image ex vivo labeled HSPCs homed within bone marrow areas, tracking interactions and movement.

במעקב 4 ממדי Vivo של תאי גזע ואבות היווצרות דם במבוגרי עכבר calvarial מח עצם

Through a delicate balance between quiescence and proliferation, self renewal and production of differentiated progeny, hematopoietic stem cells (HSCs) ...