המחברים רוצה להודות גלן סנגר-הודג'סון, מומחה בתקשורת במכללה לרפואה של בריה"מ לשעבר על כל העבודה הפקות וידאו, עריכה, ואת הקריינות.
עבודה זו נתמכה על ידי מכוני הבריאות הלאומיים (R01GM100474 ו- R01GM072611).

<ol>
	<li>Wynn, T. A., Chawla, A., Pollard, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophage+biology+in+development,+homeostasis+and+disease.">Macrophage biology in development, homeostasis and disease.</a> Nature. 496 (7446), 445-455 (2013).</li><li>Unanue, E. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antigen-presenting+function+of+the+macrophage.">Antigen-presenting function of the macrophage.</a> Annu Rev Immunol. 2, 395-428 (1984).</li><li>Cavaillon, J. 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F., Earnhardt, T., Goines, N., Bouldin, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fate+of+myelin+lipids+during+degeneration+and+regeneration+of+peripheral+nerve:+an+autoradiographic+study.">Fate of myelin lipids during degeneration and regeneration of peripheral nerve: an autoradiographic study.</a> J Neurosci. 14 (1), 357-367 (1994).</li><li>Greenhalgh, A. 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C., Zhang, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophage+activation+and+its+role+in+repair+and+pathology+after+spinal+cord+injury.">Macrophage activation and its role in repair and pathology after spinal cord injury.</a> Brain Res. , 1-11 (2015).</li><li>Bourre, J. M., Pollet, S., Daudu, O., Le Saux, F., Baumann, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myelin+consists+of+a+continuum+of+particles+of+different+density+with+varying+lipid+composition:+major+differences+are+found+between+normal+mice+and+quaking+mutants.">Myelin consists of a continuum of particles of different density with varying lipid composition: major differences are found between normal mice and quaking mutants.</a> Biochimie. 59 (10), 819-824 (1977).</li><li>Larocca, J. N., Norton, W. 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R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescent+dyes+for+lymphocyte+migration+and+proliferation+studies.">Fluorescent dyes for lymphocyte migration and proliferation studies.</a> Immunol Cell Biol. 77 (6), 499-508 (1999).</li><li>Deutsch, M. J., Schriever, S. C., Roscher, A. A., Ensenauer, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Digital+image+analysis+approach+for+lipid+droplet+size+quantitation+of+Oil+Red+O-stained+cultured+cells.">Digital image analysis approach for lipid droplet size quantitation of Oil Red O-stained cultured cells.</a> Anal Biochem. 445, 87-89 (2014).</li><li>Kroner, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TNF+and+increased+intracellular+iron+alter+macrophage+polarization+to+a+detrimental+M1+phenotype+in+the+injured+spinal+cord.">TNF and increased intracellular iron alter macrophage polarization to a detrimental M1 phenotype in the injured spinal cord.</a> Neuron. 83 (5), 1098-1116 (2014).</li><li>Trouplin, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Marrow-derived+Macrophage+Production.">Marrow-derived Macrophage Production.</a> J Vis Exp. (81), e50966 (2013).</li><li>Chen, S., So, E. C., Strome, S. E., Zhang, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+Detachment+Methods+on+M2+Macrophage+Phenotype+and+Function.">Impact of Detachment Methods on M2 Macrophage Phenotype and Function.</a> J Immunol Methods. 426, 56-61 (2015).</li><li>Guo, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rescuing+macrophage+normal+function+in+spinal+cord+injury+with+embryonic+stem+cell+conditioned+media.">Rescuing macrophage normal function in spinal cord injury with embryonic stem cell conditioned media.</a> Mol Brain. 9 (1), 48 (2016).</li><li>Bosco, D. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+synthetic+matrix+metalloproteinase+inhibitor+reduces+human+mesenchymal+stem+cell+adipogenesis.">A new synthetic matrix metalloproteinase inhibitor reduces human mesenchymal stem cell adipogenesis.</a> PLOS ONE. 12 (2), e0172925 (2017).</li><li>Ram&#237;rez-Zacar&#237;as, J. L., Castro-Mu&#241;ozledo, F., Kuri-Harcuch, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitation+of+adipose+conversion+and+triglycerides+by+staining+intracytoplasmic+lipids+with+oil+red+O.">Quantitation of adipose conversion and triglycerides by staining intracytoplasmic lipids with oil red O.</a> Histochem. 97 (6), 493-497 (1992).</li><li>Koopman, R., Schaart, G., Hesselink, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimisation+of+oil+red+staining+permits+combination+with+immunofluorescence+and+automated+quantification+of+lipids.">Optimisation of oil red staining permits combination with immunofluorescence and automated quantification of lipids.</a> Histochem Cell Biol. 116 (1), 63-68 (2001).</li><li>Fang, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lipopolysaccharide-Induced+Macrophage+Inflammatory+Response+Is+Regulated+by+SHIP.">Lipopolysaccharide-Induced Macrophage Inflammatory Response Is Regulated by SHIP.</a> J Immunol. 173 (1), (2004).</li><li>Martinez, F. O., Sica, A., Mantovani, A., Locati, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophage+activation+and+polarization.">Macrophage activation and polarization.</a> Front Biosci. 13, (2008).</li><li>Mosser, D. M., Edwards, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exploring+the+full+spectrum+of+macrophage+activation.">Exploring the full spectrum of macrophage activation.</a> Nat Rev Immunol. 8 (12), 958-969 (2008).</li></ol>

המחברים יש אין גילויים.

ההליכים המתוארים כאן לנצל טרי מבודד פסולת המיאלין גולמי של CNS והן מקרופאגים הנגזרות מח העצם העיקרי. כדי לצמצם את ההוצאה על בעלי חיים, אנו ממליצים כי שני המוח, תאי מח העצם להיות שנקטפו כל עכבר בזמנו של הקרבה. שני החוקרים עובדים ביחד יכולים להכין שני חומרים בו זמנית. לחלופין, ניתן לאחסן את המוח...

מקרופאגים הנגזרות מח העצם (BMDMs) הם חוליה חשובה בין מערכות החיסון מולדים, מסתגלת. כמו אנטיגן הצגת תאים (נגמ שים), הם יכולים לתקשר עם לימפוציטים באמצעות מצגת אנטיגן שני ולשחרר ציטוקין1,2,3. עם זאת, כמו המקצועי phagocytes, התפקיד העיקרי שלהם היא לנקות פתוגנים, תאים בגילאי ופסולת הסלולר1,4. בעקבות פגיעה בחוט השדרה (מדע), כמויות ניכרות של פסולת המיאלין נוצר מתוך oligodendrocytes גוסס, סוג התא אחראי על מערכת העצבים המרכזית האקסון myelination5. אנחנו ואחרים הראו כי סיווג של המיאלין פסולת הוא בראש ובראשונה באחריות שחדר BMDMs5,6,7. עם זאת, תוך פגיעה בחוט השדרה הוצע היבלעות באתרים של פסולת המיאלין להעביר תאים בדרך כלל אנטי דלקתיות אלה לכיוון מדינת פרו דלקתיים5,8,9. כמתווכים מרכזיים של נוירו-דלקת חוט השדרה נפגע, BMDMs הם מטרות קליני חשוב.
כדי לסייע לחקור את השפעת BMDMs בחוט השדרה הפגוע, פיתחנו מודל במבחנה ללמוד ישירות איך BMDMs להגיב המיאלין פסולת. כדי לשפר את הרלוונטיות ביולוגי, BMDMs מאתר ראשי ופסולת המיאלין מבודד טריים משמשים האלה החקירות. ככזה, השיטות המובאות כאן פירוט גם את הבידוד והתרבות של BMDMs מאתר ראשי, טכניקה הדרגתיות סוכרוז ששונה המשמשת כדי לבודד CNS מאתר נגזר המיאלין פסולת10,11,12. המיאלין פסולת יכול להיקרא בקלות עם תיוג הפלורסנט, אסתר succinimidyl carboxyfluorescein (CFSE), כדי מעקב אחר שלה הפנמה מאת BMDMs. CFSE מתאים היטב עבור יישום זה כי זה הלא-ציטוטוקסיות, היתרים ספקטרום פלורסנט הצר שלה ריבוב עם פלורסנט אחרים רגשים13,14. בעקבות phagocytosis, המיאלין פסולת שומנים מועברים דרך lysosomes, כחבילה ליפידים נייטרלי לתוך השומנים תאיים טיפות5. כדי לכמת את הצטברות השומנים תאיים, נציג של שמן אדום O (אורו) צביעת שיטת ממוטבים לניתוח תמונה כמותית. שיטה מכתימים פשוטה זו מייצרת תוצאות לשחזור חזקים כימות15. שיטות אלה להקל על המחקר של המיאלין פסולת השמירה phagocytosis ו ליפיד עם ציוד מיוחד מוגבל.

<table><tbody><tr><td>DMEM</td><td>GE Healthcare Life Sciences</td><td>SH30243.01</td><td>High glucose with L-glutamine, sodium pyruvate</td></tr><tr><td>Penicillin-Streptomycin Solution</td><td>Corning</td><td>30-002-CI</td><td>100X Solution</td></tr><tr><td>New Born Calf Serum (NCS)</td><td>Rocky Mountain Biologics</td><td>NBS-BBT-5XM</td><td>United States Origin</td></tr><tr><td>NCTC clone 929 [L cell, L-929, derivative of Strain L]&amp;nbsp;</td><td>ATCC</td><td>CCL-1</td><td>L929 Cell Line of Conditioned Media Preparation</td></tr><tr><td>24-well Cell Culture Plates</td><td>VWR</td><td>10062-896&amp;nbsp;</td><td></td></tr><tr><td>Cell Culture Dish</td><td>Greiner Bio-One</td><td>639960</td><td>Polystyrine, 145/20mm</td></tr><tr><td>CFSE Cell Proliferation Kit</td><td>Thermo Fisher</td><td>C34570</td><td>DMSO for Reconsitution Provided</td></tr><tr><td>Fluoro-gel with Tris Buffer&amp;nbsp;</td><td>Electron Microscopy Sciences</td><td>17985-11</td><td></td></tr><tr><td>Oil Red O</td><td>Sigma Aldrich</td><td>O0625</td><td></td></tr><tr><td>&lt;strong&gt;Equipment&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>&lt;strong&gt;Materials&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>Ultracentrifuge Tubes</td><td>Beckman Coulter</td><td>326823</td><td>Thinwall, Polypropylene, 38.5 mL, 25 x 89 mm</td></tr><tr><td>SW 32 Ti Ultracentrifuge Rotor</td><td>Beckman Coulter</td><td>369650</td><td>SW 32 Ti Rotor, Swinging Bucket, Titanium</td></tr><tr><td>Hand Held Rotary Homogenizer</td><td>Fisher Science</td><td>08-451-71</td><td></td></tr></tbody></table>

in vitro phagocytosis of myelin debris by bone marrow-derived macrophages

מקרופאגים הנגזרות מח העצם (BMDMs) הם לויקוציטים בוגרת לשרת תפקיד פיזיולוגי קריטיים כמו phagocytes מקצועי המסוגל סליקה מגוון של חלקיקים. בדרך כלל, BMDMs שנאסרת על מערכת העצבים המרכזית (CNS), אך בעקבות פציעה, הם בקלות יכולים לחדור. פעם אחת בתוך הרקמה הפצועים CNS, BMDMs הם סוג התא הראשי אחראי האישור של פציעה, נגזר הסלולר פסולת, כולל כמויות גדולות של פסולת המיאלין עשיר השומנים. ההשלכות neuropathological של BMDM חדירה של המיאלין פסולת phagocytosis בתוך מערכת העצבים הן מורכבות לא הבין היטב. הפרוטוקולים המתוארים כאן, לאפשר לחקר ישירה במבחנה BMDMs בהקשר של פגיעה CNS. אנחנו מכסים בידוד BMDM מאתר ואת התרבות המיאלין פסולת הכנה, מבחני להעריך BMDM מיאלין פסולת phagocytosis. טכניקות אלה לתוצאות לכימות חזקים ללא צורך משמעותי ציוד מיוחד או חומרים, עדיין ניתן בקלות להתאים אישית לצרכים של החוקרים.

טיפול של BMDMs עם CFSE שכותרתו המיאלין פסולת אמור להניב ברור הפנמה (איור 2). בעוד זמן האינטראקציה 3 שעות מספיקה עבור BMDMs phagocytose מספיק פסולת המיאלין נוסף לגילוי במורד הזרם חזקים, הצטברות תאיים יכול להיות שנצפו עם מעט ככל 1 שעה של אינטראקציה. עם זאת, יש שרידים המיאלין עדיין ייתכן בהוו...

Watch this Scientific Journal Video about In Vitro Phagocytosis of Myelin Debris by Bone Marrow-Derived Macrophages at JoVE.com

In Vitro Phagocytosis of Myelin Debris by Bone Marrow-Derived Macrophages

אנו מציגים שיטות כדי להעריך את יכולת phagocytic של ראשי מאתר הנגזרות מח עצם מקרופאגים באמצעות פסולת מיאלין fluorescently שכותרתו השומנים תאיים droplet מכתים.

במבחנה Phagocytosis של המיאלין פסולת על ידי מקרופאגים הנגזרות מח עצם

Bone marrow-derived macrophages (BMDMs) are mature leukocytes that serve a critical physiological role as professional phagocytes capable of clearing a ...

in-vitro-phagocytosis-myelin-debris-bone-marrow-derived

Research

JoVE Journal

Neuroscience

In Vitro Phagocytosis of Myelin Debris by Bone Marrow-Derived Macrophages

12.7K Views.  Florida State University. אנו מציגים שיטות כדי להעריך את יכולת phagocytic של ראשי מאתר הנגזרות מח עצם מקרופאגים באמצעות פסולת מיאלין fluorescently שכותרתו השומנים תאיים droplet מכתים.

Video: In Vitro Phagocytosis of Myelin Debris by Bone Marrow-Derived Macrophages

Depletion and Reconstitution of Macrophages in Mice

Macrophages are critical players in the innate immune response to infectious challenge or injury, initiating the innate immune response and directing the acquired immune response. Macrophage dysfunction can lead to an inability to mount an appropriate immune response and as such, has been implicated in many disease processes, including inflammatory bowel diseases. Macrophages display polarized phenotypes that are broadly divided into two categories. Classically activated macrophages, activated by stimulation with IFN&gamma; or LPS, play an essential role in response to bacterial challenge whereas alternatively activated macrophages, activated by IL-4 or IL-13, participate in debris scavenging and tissue remodeling and have been implicated in the resolution phase of inflammation. During an inflammatory response in vivo, macrophages are found amid a complex mixture of infiltrating immune cells and may participate by exacerbating or resolving inflammation. To define the role of macrophages in situ in a whole animal model, it is necessary to examine the effect of depleting macrophages from the complex environment. To ask questions about the role of macrophage phenotype in situ, phenotypically defined polarized macrophages can be derived ex vivo, from bone marrow aspirates and added back to mice, with or without prior depletion of macrophages. In the protocol presented here clodronate-containing liposomes, versus PBS injected controls, were used to deplete colonic macrophages during dextran sodium sulfate (DSS)-induced colitis in mice. In addition, polarized macrophages were derived ex vivo and transferred to mice by intravenous injection. A caveat to this approach is that clodronate-containing liposomes deplete all professional phagocytes, including both dendritic cells and macrophages so to ensure the effect observed by depletion is macrophage-specific, reconstitution of phenotype by adoptive transfer of macrophages is necessary. Systemic macrophage depletion in mice can also be achieved by backcrossing mice onto a CD11b-DTR background, which is an excellent complementary approach. The advantage of clodronate-containing liposome-mediated depletion is that it does not require the time and expense involved in backcrossing mice and it can be used in mice regardless of the background of the mice (C57BL/6, BALB/c, or mixed background).

Macrophages play a central role in homeostasis and pathology in many tissues. The protocol presented here describes methods for depleting macrophages in vivo, deriving polarized macrophages from bone marrow aspirates, and adoptively transferring macrophages into mice. These techniques allow determination of the role that polarized macrophages play in health and disease.

דלדול המשאבים ואת הכינון מחדש של מקרופאגים בעכברים

Macrophages are critical players in the innate  immune response to infectious challenge or injury, initiating the innate immune  response and directing ...

Immunology and Infection

Bone Marrow-derived Macrophage Production

Macrophages are critical components of the innate and adaptive immune responses, and they are the first line of defense against foreign invaders because of their powerful microbicidal activities. Macrophages are widely distributed throughout the body and are present in the lymphoid organs, liver, lungs, gastrointestinal tract, central nervous system, bone, and skin. Because of their repartition, they participate in a wide range of physiological and pathological processes. Macrophages are highly versatile cells that are able to recognize microenvironmental alterations and to maintain tissue homeostasis. Numerous pathogens have evolved mechanisms to use macrophages as Trojan horses to survive, replicate in, and infect both humans and animals and to propagate throughout the body. The recent explosion of interest in evolutionary, genetic, and biochemical aspects of host-pathogen interactions has renewed scientific attention regarding macrophages. Here, we describe a procedure to isolate and cultivate macrophages from murine bone marrow that will provide large numbers of macrophages for studying host-pathogen interactions as well as other processes.

Macrophages have long been recognized as a critical component of the innate and adaptive immune responses. The recent explosion of knowledge pertaining to evolutionary, genetic, and biochemical aspects of the interaction between macrophages and microbes has renewed scientific attention to macrophages. This article describes a method to differentiate macrophages from mouse bone marrow.

מח עצם נגזרות Macrophage הפקה

Macrophages are critical components of the innate and adaptive immune responses, and they are the first line of defense against foreign invaders because ...

Study of Phagolysosome Biogenesis in Live Macrophages

Phagocytic cells play a major role in the innate immune system by removing and eliminating invading microorganisms in their phagosomes. Phagosome maturation is the complex and tightly regulated process during which a nascent phagosome undergoes drastic transformation through well-orchestrated interactions with various cellular organelles and compartments in the cytoplasm. This process, which is essential for the physiological function of phagocytic cells by endowing phagosomes with their lytic and bactericidal properties, culminates in fusion of phagosomes with lysosomes and biogenesis of phagolysosomes which is considered to be the last and critical stage of maturation for phagosomes. In this report, we describe a live cell imaging based method for qualitative and quantitative analysis of the dynamic process of lysosome to phagosome content delivery, which is a hallmark of phagolysosome biogenesis. This approach uses IgG-coated microbeads as a model for phagocytosis and fluorophore-conjugated dextran molecules as a luminal lysosomal cargo probe, in order to follow the dynamic delivery of lysosmal content to the phagosomes in real time in live macrophages using time-lapse imaging and confocal laser scanning microscopy. Here we describe in detail the background, the preparation steps and the step-by-step experimental setup to enable easy and precise deployment of this method in other labs. Our described method is simple, robust, and most importantly, can be easily adapted to study phagosomal interactions and maturation in different systems and under various experimental settings such as use of various phagocytic cells types, loss-of-function experiments, different probes, and phagocytic particles.

חקר Phagolysosome Biogenesis בהמקרופאגים בשידור חי

Phagocytic cells play a major role in the innate immune system by removing and eliminating invading microorganisms in their phagosomes. Phagosome ...

An Engulfment Assay: A Protocol to Assess Interactions Between CNS Phagocytes and Neurons

Phagocytosis is a process in which a cell engulfs material (entire cell, parts of a cell, debris, etc.) in its surrounding extracellular environment and subsequently digests this material, commonly through lysosomal degradation. Microglia are the resident immune cells of the central nervous system (CNS) whose phagocytic function has been described in a broad range of conditions from neurodegenerative disease (e.g., beta-amyloid clearance in Alzheimer&#8217;s disease) to development of the healthy brain (e.g., synaptic pruning)1-6. The following protocol is an engulfment assay developed to visualize and quantify microglia-mediated engulfment of presynaptic inputs in the developing mouse retinogeniculate system7. While this assay was used to assess microglia function in this particular context, a similar approach may be used to assess other phagocytes throughout the brain (e.g., astrocytes) and the rest of the body (e.g., peripheral macrophages) as well as other contexts in which synaptic remodeling occurs (e.g. ,brain injury/disease).

Microglia are the resident immune cells of the central nervous system (CNS) with a high capacity to phagocytose or engulf material in their extracellular environment. Here, a broadly applicable, reliable, and highly quantitative assay for visualizing and measuring microglia-mediated engulfment of synaptic components is described.

Assay היבלעות: פרוטוקול להעריך אינטראקציות בין מערכת העצבים המרכזית וPhagocytes נוירונים

Phagocytosis is a process in which a cell engulfs material (entire cell, parts of a cell, debris, etc.) in its surrounding extracellular environment and ...

Metabolic Characterization of Polarized M1 and M2 Bone Marrow-derived Macrophages Using Real-time Extracellular Flux Analysis

Specific metabolic pathways are increasingly being recognized as critical hallmarks of macrophage subsets. While LPS-induced classically activated M1 or M(LPS) macrophages are pro-inflammatory, IL-4 induces alternative macrophage activation and these so-called M2 or M(IL-4) support resolution of inflammation and wound healing. Recent evidence shows the crucial role of metabolic reprogramming in the regulation of M1 and M2 macrophage polarization. 
In this manuscript, an extracellular flux analyzer is applied to assess the metabolic characteristics of naive, M1 and M2 polarized mouse bone marrow-derived macrophages. This instrument uses pH and oxygen sensors to measure the extracellular acidification rate (ECAR) and oxygen consumption rate (OCR), which can be related to glycolytic and mitochondrial oxidative metabolism. As such, both glycolysis and mitochondrial oxidative metabolism can be measured in real-time in one single assay.
Using this technique, we demonstrate here that inflammatory M1 macrophages display enhanced glycolytic metabolism and reduced mitochondrial activity. Conversely, anti-inflammatory M2 macrophages show high mitochondrial oxidative phosphorylation (OXPHOS) and are characterized by an enhanced spare respiratory capacity (SRC). 
The presented functional assay serves as a framework to investigate how particular cytokines, pharmacological compounds, gene knock outs or other interventions affect the macrophage&#8217;s metabolic phenotype and inflammatory status.

Metabolic reprogramming is a characteristic and prerequisite for M1 and M2 macrophage polarization. This manuscript describes an assay for the measurement of fundamental parameters of glycolysis and mitochondrial function in mouse bone marrow-derived macrophages. This tool can be applied to investigate how particular factors affect the macrophage&#8217;s metabolism and phenotype.

אפיון חילוף חומרים של מקוטב M1 והמקרופאגים נגזר מח עצם M2 באמצעות ניתוח תאי שטף בזמן אמת

Specific metabolic pathways are increasingly being recognized as critical hallmarks of macrophage subsets. While LPS-induced classically activated M1 or ...

Mesenchymal Stem Cell Regulation of Macrophage Phagocytosis; Quantitation and Imaging

Mesenchymal stem cells (MSC) have traditionally been studied for their regenerative properties, but more recently, their immunoregulatory characteristics have been at the forefront. They interact with and regulate immune cell activity. The focus of this study is the MSC regulation of macrophage phagocytic activity. Macrophage (M&#934;) phagocytosis is an important part of the innate immune system response to infection, and the mechanisms through which MSC modulate this response are under active investigation. Presented here is a method to study M&#934; phagocytosis of non-opsonized zymosan particles conjugated to a pH-sensitive fluorescent molecule while in co-culture with MSC. As phagocytic activity increases and the labeled zymosan particles are enclosed within the acidic environment of the phagolysosome, the fluorescence intensity of the pH-sensitive molecule increases. With the appropriate excitation and emission wavelengths, phagocytic activity is measured using a fluorescent spectrophotometer and kinetic data is presented as changes in relative fluorescent units over a 70 min period. To support this quantitative data, the change in the phagocytic activity is visualized using dynamic imaging. Results using this method demonstrate that when in co-culture, MSC enhance M&#934; phagocytosis of non-opsonized zymosan of both naive and IFN-&#947; treated M&#934;. These data add to the current knowledge of MSC regulation of the innate immune system. This method can be applied in future investigations to fully delineate the underlying cellular and molecular mechanisms.

Presented here is a protocol to quantify and produce dynamic images of mesenchymal stem cell (MSC) mediated regulation of macrophage (M&#934;) phagocytosis of non-opsonized yeast (zymosan) particles that are conjugated to a pH-sensitive fluorescent molecule.

ויסות תאי גזע מזנכימליים של מקרופאג' פאגוציטוזיס; כמות והדמיה

Mesenchymal stem cells (MSC) have traditionally been studied for their regenerative properties, but more recently, their immunoregulatory characteristics ...

Flow Cytometry Approach to Characterize Phagocytic Properties of Acutely-Isolated Adult Microglia and Brain Macrophages In Vitro

Microglia and central nervous system (CNS)-infiltrating macrophages, collectively called CNS mononuclear phagocytes (CNS-MPs), play central roles in neurological diseases including neurodegeneration and stroke. CNS-MPs are involved in phagocytic clearance of pathological proteins, debris and neuronal synapses, each with distinct underlying molecular pathways. Characterizing these phagocytic properties can provide a functional readout that compliments molecular profiling of microglia using traditional flow cytometry, transcriptomics and proteomics approaches. Phagocytic profiling of microglia has relied on microscopic visualization and in vitro cultures of mouse neonatal microglia. The former approach suffers from limited sampling while the latter approach is inherently poorly reflective of the true in vivo state of adult CNS-MPs. This paper describes optimized protocols to phenotype phagocytic properties of acutely-isolated mouse CNS-MPs by flow cytometry. CNS-MPs are acutely isolated from adult mouse brain using mechanical dissociation followed by density gradient centrifugation, incubated with fluorescent microspheres or fluorescent A&#946; fibrils, washed, and then labeled with panels of antibodies against surface markers (CD11b, CD45). Using this approach, it is possible to compare phagocytic properties of brain-resident microglia with CNS-infiltrating macrophages and then assess the effect of aging and disease pathology on these phagocytic phenotypes. This rapid method also holds potential to functionally phenotype acutely-isolated human CNS-MPs from post-mortem or surgical brain specimens. Additionally, specific mechanisms of phagocytosis by CNS-MP subsets can be investigated by inhibiting select phagocytic pathways.

<meta charset="utf8"></head><body>גישת זרימה ציטומטרית לאפיון תכונות פגוציטיות של מיקרוגליה בוגרת מבודדת חריפה ומקרופאגים במוח במבחנה

Assessment of phagocytic properties of microglia and brain macrophages can provide a valuable functional dimension to molecular profiling studies. We describe a validated protocol that uses flow cytometry to rapidly and reliably quantify phagocytosis of fluorescent microspheres and amyloid beta fibrils by acutely-isolated microglia and brain macrophages from mouse models.

גישת זרימה ציטומטרית לאפיון תכונות פגוציטיות של מיקרוגליה בוגרת מבודדת חריפה ומקרופאגים במוח במבחנה

Microglia and central nervous system (CNS)-infiltrating macrophages, collectively called CNS mononuclear phagocytes (CNS-MPs), play central roles in ...

Isolation and Culture of Bone Marrow-Derived Macrophages from Mice

Macrophages have important effector functions in homeostasis and inflammation. These cells are present in every tissue in the body and have the important ability to change their profile according to the stimuli present in the microenvironment. Cytokines can profoundly affect macrophage physiology, especially IFN-&#947; and interleukin 4, generating M1 and M2 types respectively. Because of the versatility of these cells, the production of a population of bone marrow-derived macrophages can be a basic step in many experimental models of cell biology. The aim of this protocol is to help researchers in the isolation and culture of macrophages derived from bone marrow progenitors. Bone marrow progenitors from pathogen-free C57BL/6 mice are transformed into macrophages upon exposure to macrophage colony-stimulating factor (M-CSF) that, in this protocol, is obtained from the supernatant of the murine fibroblast lineage L-929. After incubation, mature macrophages are available for use from the 7th to the 10th day. A single animal can be the source of approximately 2 x 107 macrophages. Therefore, it is an ideal protocol for obtaining large amounts of primary macrophages using basic methods of cell culture.

The present protocol describes the isolation and culture of bone marrow-derived macrophages from mice.

בידוד ותרבית של מקרופאגים שמקורם במח עצם מעכברים

Macrophages have important effector functions in homeostasis and inflammation. These cells are present in every tissue in the body and have the important ...

In vitro Quantitative Imaging Assay for Phagocytosis of Dead Neuroblastoma Cells by iPSC-Macrophages

Microglia orchestrate neuroimmune responses in several neurodegenerative diseases, including Parkinson&#39;s disease and Alzheimer&#39;s disease. Microglia clear up dead and dying neurons through the process of efferocytosis, a specialized form of phagocytosis. The phagocytosis function can be disrupted by environmental or genetic risk factors that affect microglia. This paper presents a rapid and simple in vitro&#160;microscopy protocol for studying microglial efferocytosis in an induced pluripotent stem cell (iPSC) model of microglia, using a human neuroblastoma cell line (SH-SY5Y) labeled with a pH-sensitive dye for the phagocytic cargo. The procedure results in a high yield of dead neuroblastoma cells, which display surface phosphatidylserine, recognized as an &#34;eat-me&#34; signal by phagocytes. The 96-well plate assay is suitable for live-cell time-lapse imaging, or the plate can be successfully fixed prior to further processing and quantified by high-content microscopy. Fixed-cell high-content microscopy enables the assay to be scaled up for screening of small molecule inhibitors or assessing the phagocytic function of genetic variant iPSC lines. While this assay was developed to study phagocytosis of whole dead neuroblastoma cells by iPSC-macrophages, the assay can be easily adapted for other cargoes relevant to neurodegenerative diseases, such as synaptosomes and myelin, and other phagocytic cell types.

Neurodegenerative diseases are associated with dysregulated microglia functions. This article outlines an in vitro assay of phagocytosis of neuroblastoma cells by iPSC-macrophages. Quantitative microscopy readouts are described for both live-cell time-lapse imaging and fixed-cell high-content imaging.

במבחנה Phagocytosis של המיאלין פסולת על ידי מקרופאגים הנגזרות מח עצם

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דלדול המשאבים ואת הכינון מחדש של מקרופאגים בעכברים

מח עצם נגזרות Macrophage הפקה

חקר Phagolysosome Biogenesis בהמקרופאגים בשידור חי

Assay היבלעות: פרוטוקול להעריך אינטראקציות בין מערכת העצבים המרכזית וPhagocytes נוירונים

אפיון חילוף חומרים של מקוטב M1 והמקרופאגים נגזר מח עצם M2 באמצעות ניתוח תאי שטף בזמן אמת

ויסות תאי גזע מזנכימליים של מקרופאג' פאגוציטוזיס; כמות והדמיה

גישת זרימה ציטומטרית לאפיון תכונות פגוציטיות של מיקרוגליה בוגרת מבודדת חריפה ומקרופאגים במוח במבחנה

גישת זרימה ציטומטרית לאפיון תכונות פגוציטיות של מיקרוגליה בוגרת מבודדת חריפה ומקרופאגים במוח במבחנה

בידוד ותרבית של מקרופאגים שמקורם במח עצם מעכברים

במבחנה הדמיה כמותית אסאי עבור פאגוציטוזיס של תאי נוירובלסטומה מתים על ידי iPSC-מקרופאגים