Bu çalışma NCI R01 CA120659 (SC) tarafından desteklenmiştir.

1. Tümör Hücrelerinin vaskülojenik Faaliyet değerlendirin bir Matrigel Tabanlı Tüp Oluşumu Testi <ol><li> , Tümör hücreleri ve mikrovasküler endotel hücreleri Hazırlanması: U87 hücreleri, melanom hücrelerinin B16F1, meme kanseri MDA-MB-435 ve kolon hücrelerinin HCT116 gibi beyin tümör hücreleri (% 10 FBS ve penisilin / streptomisin ile desteklenmiş DMEM yetiştirilen tüm Invitrogen gelen .) Endotel hücre hattı insan mikrovasküler endotel hücreleri (HMVECs) 1 mcg / ml hidrokortizon ve 1 ng / ml epidermal büyüme faktörü,% 10 FBS ve penisilin / streptomisin ile desteklenmiş EBM2 orta (Lonza) kültüre edildi. Hücreler PBS üç kez yıkanır ve% 0.05 tripsin / EDTA (Invitrogen) ile müstakil edildi. 2,000 rpm ile 5 dakika süreyle santrifüj sonra, hücre pelletleri tekrar PBS ile yıkandı. Sonra, bir hemasitometre pelet hücreleri sayıldı. </li><li> Matrigel hazırlık: Bir kısım büyüme faktörü-azaltılmış Matrigel (BD Bioscience), oda sıcaklığında ısınmış. Tamamen çözülmüş önce, buz üzerine transfer edildi ve sıvı, en az 10 dakika boyunca buz üzerinde tutulmalıdır. Sonra Matrigel 50 ul Matrigel eşit olarak dağıtmak için izin veren bir yatay düzeyde 96-kuyucuğu kaplama, 37 ° C&#39;de 30 dakika inkübe edildi </li><li> Tüp oluşumu: hücreler (1-2 x 10 4), endotel hücreleri tümör hücrelerinin ya da EBM-2 serum serbest DMEM ile yeniden askıya alınan ve Matrigel üst üzerinde yüklü idi . Bu testte tübül gelişimi üzerine bazı ajanların etkilerini ölçmek için kullanılmış ise, bu ajanlar (uyarıcıları veya inhibitörleri), serum serbest orta eklendi. Her koşullu grup 4-6 kuyu içeriyordu. </li><li> Görüntü ve veri analizi: 37 takiben kuluçka ° C gecede, her iyi, doğrudan mikroskop altında incelendi. Tübüller sabitleme için gerekli olsaydı,% 10 formalin tuzlu tabanlı çözüm ul 100 nazikçe eklendi ve on dakika sonra, analiz için hazır. 10x faz kontrast mikroskop altında, her alanda tübüller görüntülü ve ortalama 3-5 rastgele alanlardan her kuyuda Tübüllerin bir sayılmıştır. </li></ol> 2. Temsilcisi Sonuçlar: Bu tübüller, poligon ağı oluşturmak bağlanmak uzatılmış hücre gövdeleri üretilmişti HMVECs, pozitif kontrol olarak kullanıldı. B16F1, U87 ve MDA-MB-435 hücre HMVECs tarafından oluşturulan benzer vasküler tübüller geliştirilmiş, ancak HCT116 hücreleri (Şekil 1) vermedi. Doza bağımlı bir hücre tüp oluşumu U87 hücreleri test edildi. Şekil 2&#39;de gösterildiği gibi, 10.000 hücreleri durdurulan tübüller kurdu. Hücrelerin iki katına sonra, sağlam bir damar ağı HMVECs olarak görülen karşılaştırılabilir. Buna karşılık, 5.000 &#39;den az hücreleri vasküler bir fenotip oluşturmak için başarısız oldu. <img src="/files/ftp_upload/3040/3040fig1.jpg" alt="Şekil 1"/> Şekil 1 Tüp oluşumu HMVECs, U87, MDA-MB-435, ve B16F1 hücreleri tarafından uyarılan, ancak HCT116 hücreler, tüm hücrelerin (2 x 10 4) Matrigel üzerinde yüklü olan ve gece boyunca inkübe edildi . Tübüller faz kontrast kullanılarak görüntülenmiştir. HMVECs Pozitif kontrol olarak kullanılmıştır. 3-5 alanların bir temsilci gösterildi. Bar: 100 mikron. <img src="/files/ftp_upload/3040/3040fig2.jpg" alt="Şekil 2"/> Şekil 2 hücre sayısı bağımlı bir şekilde hücre kaynaklı U87 tübüller Farklı sayıda köşeleri belirtildiği gibi U87 hücrelerinin tüp oluşumu için kullanılmıştır. HMVECs pozitif kontrol için kullanılmıştır. Bar: 100 mm.

<ol>
	<li>Shao, R., Guo, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+microvascular+endothelial+cells+immortalized+with+human+telomerase+catalytic+protein:+a+model+for+the+study+of+in+vitro+angiogenesis.">Human microvascular endothelial cells immortalized with human telomerase catalytic protein: a model for the study of in vitro angiogenesis.</a> Biochemical &#38; Biophysical Research Communications. 321, 788-794 (2004).</li><li>Ribeiro, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hemostatic+properties+of+the+SV-40+transfected+human+microvascular+endothelial+cell+line+(HMEC-1).+A+representative+in+vitro+model+for+microvascular+endothelium.">Hemostatic properties of the SV-40 transfected human microvascular endothelial cell line (HMEC-1). 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K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+clinical+significance+of+tumor+cell-lined+vasculature+in+ovarian+carcinoma:+implications+for+anti-vasculogenic+therapy.">The clinical significance of tumor cell-lined vasculature in ovarian carcinoma: implications for anti-vasculogenic therapy.</a> Cancer Biology &#38; Therapy. 1, 661-664 (2002).</li><li>Shirakawa, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hemodynamics+in+vasculogenic+mimicry+and+angiogenesis+of+inflammatory+breast+cancer+xenograft.">Hemodynamics in vasculogenic mimicry and angiogenesis of inflammatory breast cancer xenograft.</a> Cancer Research. 62, 560-566 (2002).</li><li>Ruf, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+role+of+tissue+factor+pathway+inhibitors+1+and+2+in+melanoma+vasculogenic+mimicry.">Differential role of tissue factor pathway inhibitors 1 and 2 in melanoma vasculogenic mimicry.</a> Cancer Research. 63, 5381-5389 (2003).</li><li>Seftor, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cooperative+interactions+of+laminin+5+gamma2+chain,+matrix+metalloproteinase-2,+and+membrane+type-1-matrix/metalloproteinase+are+required+for+mimicry+of+embryonic+vasculogenesis+by+aggressive+melanoma.">Cooperative interactions of laminin 5 gamma2 chain, matrix metalloproteinase-2, and membrane type-1-matrix/metalloproteinase are required for mimicry of embryonic vasculogenesis by aggressive melanoma.</a> Cancer Research. 61, 6322-6327 (2001).</li><li>Shirakawa, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vasculogenic+mimicry+and+pseudo-comedo+formation+in+breast+cancer.">Vasculogenic mimicry and pseudo-comedo formation in breast cancer.</a> International Journal of Cancer. 99, 821-828 (2002).</li></ol>

Çıkar çatışması ilan etti.

Bu testte başarılı olmak için, Matrigel kalitesini ilk test edilmelidir. Bioscience BD HMVECs kullanarak tahlil öncesi çalıştırmak için küçük bir örnek alınabilir. Farklı parti ürünleri, bazı çok sayıda tüp oluşumu için en uygun durumda vermezseniz hangi benzemeyen nitelikler gösterebilir. Matrigel bir kısım 96-kuyucuğu yüklendiğinde kabarcıkları tübül oluşumu bozabilir çünkü İkincisi, herhangi bir kabarcıkları kaçınılmalıdır olmalıdır. Minik kabarcıklar iyi tespit edilir...

<table border="1"><tbody><tr><th> Reaktifin Adı </th><th> Şirket </th><th> Katalog numarası </th></tr><tr><td> DMEM </td><td> Invitrogen </td><td> 11995 </td></tr><tr><td> FBS </td><td> Invitrogen </td><td> 16000-044 </td></tr><tr><td> Büyüme faktörü-azaltılmış Matrigel </td><td> Bioscience BD </td><td> 47743-720 </td></tr><tr><td> EBM2 kiti </td><td> Lonza </td><td> CC-3156 </td></tr><tr><td> Nikon ECLIPSE TS100 mikroskop </td><td> Nikon </td><td></td></tr></tbody></table>

a matrigel-based tube formation assay to assess the vasculogenic activity of tumor cells

Geçtiğimiz birkaç on yıl içinde, bir tüp oluşum denemesi büyüme kullanarak faktör-azaltılmış Matrigel genellikle vasküler endotelyal hücrelerin in vitro 1-5 anjiyogenik faaliyet göstermek için istihdam edilmiştir . Ancak, son zamanlarda giderek artan kanıtlar, bu testte, vasküler endotelyal hücreler için davranış test etmek için sınırlı olmadığını göstermiştir. Bunun yerine, aynı zamanda tümör hücrelerinin damar fenotip 6-8 geliştirmek için bir dizi yeteneğini test etmek için kullanılır olmuştur . Bu yeteneği, xenotransplanted hayvanlar, vaskülojenik taklit (VM) 9 olarak bilinen bir süreç olarak tanımlanan vaskülojenik davranışı ile uyumlu idi . Tümör hücre-aracılı VM, endotelyal hücre anjiyogenez 6, 10-13, bağımsız, tümör gelişiminde hayati bir rol oynar gösteren çok sayıda kanıt vardır. Örneğin, tümör hücrelerinin melanoma ve glioblastoma hasta 8, 10, 11 kan, doku örnekleri perfüze, vasküler kanal oluşumu katılmak bulundu . Burada, tümör hücrelerinin vaskülojenik aktivite değerlendirilmesi yararlı bir araç olarak bu borulu şebeke tahlil nitelendirdi. Biz böyle melanom B16F1 hücreleri, glioblastoma U87 hücreleri ve meme kanseri MDA-MB-435 hücre gibi bazı tümör hücre hatları vasküler tübüller formu mümkün olduğunu, ancak bazı kolon kanseri HCT116 hücreleri gibi değil. Ayrıca, bu vasküler fenotip Matrigel kaplanmış hücre sayıları bağlıdır. Bu nedenle, bu testte vasküler potansiyel vasküler hücreler, tümör hücreleri gibi diğer hücrelere de dahil olmak üzere çeşitli hücre tipleri ekrana güçlü bir yardımcı olarak hizmet verebilir.

Watch this Scientific Journal Video about A Matrigel-Based Tube Formation Assay to Assess the Vasculogenic Activity of Tumor Cells at JoVE.com

A Matrigel-Based Tube Formation Assay to Assess the Vasculogenic Activity of Tumor Cells

Bir tüp oluşum denemesi tümör hücrelerinin damar etkinliğini değerlendirmek için kullanılır.

Tümör Hücrelerinin vaskülojenik Faaliyet değerlendirin bir Matrigel Tabanlı Tüp Oluşumu Testi

Over the past several decades, a tube formation assay using growth factor-reduced Matrigel has been typically employed to demonstrate the angiogenic ...

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Biology

66.0K Görüntüleme.  University of Massachusetts. Bir tüp oluşum denemesi tümör hücrelerinin damar etkinliğini değerlendirmek için kullanılır.

Video: A Matrigel-Based Tube Formation Assay to Assess the Vasculogenic Activity of Tumor Cells

An Assay for Measuring the Activity of Escherichia coli Inducible Lysine Decarboxyase

Escherichia coli is an enteric bacterium that is capable of growing over a wide range of pH values (pH 5 - 9)1 and, incredibly, is able to survive extreme acid stresses including passage through the mammalian stomach where the pH can fall to as low as pH 1 - 22. To enable such a broad range of acidic pH survival, E. coli possesses four different inducible amino acid decarboxylases that decarboxylate their substrate amino acids in a proton-dependent manner thus raising the internal pH. The decarboxylases include the glutamic acid decarboxylases GadA and GadB3, the arginine decarboxylase AdiA4, the lysine decarboxylase LdcI5, 6 and the ornithine decarboxylase SpeF7. All of these enzymes utilize pyridoxal-5'-phospate as a co-factor8 and function together with inner-membrane substrate-product antiporters that remove decarboxylation products to the external medium in exchange for fresh substrate2. In the case of LdcI, the lysine-cadaverine antiporter is called CadB. Recently, we determined the X-ray crystal structure of LdcI to 2.0 &#197;, and we discovered a novel small-molecule bound to LdcI the stringent response regulator guanosine 5'-diphosphate,3'-diphosphate (ppGpp) 14. The stringent response occurs when exponentially growing cells experience nutrient deprivation or one of a number of other stresses9. As a result, cells produce ppGpp which leads to a signaling cascade culminating in the shift from exponential growth to stationary phase growth10. We have demonstrated that ppGpp is a specific inhibitor of LdcI 14. Here we describe the lysine decarboxylase assay, modified from the assay developed by Phan et al.11, that we have used to determine the activity of LdcI and the effect of pppGpp/ppGpp on that activity. The LdcI decarboxylation reaction removes the &alpha;-carboxy group of L-lysine and produces carbon dioxide and the polyamine cadaverine (1,5-diaminopentane)5. L-lysine and cadaverine can be reacted with 2,4,6-trinitrobenzensulfonic acid (TNBS) at high pH to generate N,N'-bistrinitrophenylcadaverine (TNP-cadaverine) and N,N&#8242;-bistrinitrophenyllysine (TNP-lysine), respectively11. The TNP-cadaverine can be separated from the TNP-lysine as the former is soluble in organic solvents such as toluene while the latter is not (See Figure 1). The linear range of the assay was determined empirically using purified cadaverine.

An Assay for Measuring the Activity of Escherichia coli Inducible Lysine Decarboxyase

The activity of the inducible lysine decarboxylase is monitored by reacting the substrate L-lysine and the product cadaverine with 2,4,6-trinitrobenzensulfonic acid to form adducts that have differential solubility in toluene.

Etkinlik Ölçüm Bir Testi Escherichia coli Lizin Decarboxyase Đndüklenebilir

Escherichia coli is an enteric bacterium that is capable of growing over a wide range of pH values (pH 5 - 9)1 and, incredibly, is able to survive extreme ...

Biyoloji

Clonogenic Assay: Adherent Cells

The clonogenic (or colony forming) assay has been established for more than 50 years; the original paper describing the technique was published in 19561. Apart from documenting the method, the initial landmark study generated the first radiation-dose response curve for X-ray irradiated mammalian (HeLa) cells in culture1. Basically, the clonogenic assay enables an assessment of the differences in reproductive viability (capacity of cells to produce progeny; i.e. a single cell to form a colony of 50 or more cells) between control untreated cells and cells that have undergone various treatments such as exposure to ionising radiation, various chemical compounds (e.g. cytotoxic agents) or in other cases genetic manipulation. The assay has become the most widely accepted technique in radiation biology and has been widely used for evaluating the radiation sensitivity of different cell lines. Further, the clonogenic assay is commonly used for monitoring the efficacy of radiation modifying compounds and for determining the effects of cytotoxic agents and other anti-cancer therapeutics on colony forming ability, in different cell lines. A typical clonogenic survival experiment using adherent cells lines involves three distinct components, 1) treatment of the cell monolayer in tissue culture flasks, 2) preparation of single cell suspensions and plating an appropriate number of cells in petri dishes and 3) fixing and staining colonies following a relevant incubation period, which could range from 1-3 weeks, depending on the cell line. Here we demonstrate the general procedure for performing the clonogenic assay with adherent cell lines with the use of an immortalized human keratinocyte cell line (FEP-1811)2. Also, our aims are to describe common features of clonogenic assays including calculation of the plating efficiency and survival fractions after exposure of cells to radiation, and to exemplify modification of radiation-response with the use of a natural antioxidant formulation.

The applicability of the clonogenic assay for evaluating reproductive viability has been established for more than 50 years. Here we demonstrate the general procedure for performing the clonogenic assay with adherent cells.

Clonogenic Testi: yapışkan Hücreler

The clonogenic (or colony forming) assay has been established for more than 50 years; the original paper describing the technique was published in 19561. ...

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 Kültür İlköğretim İnsan Fallop Tüp Epitel Hücreleri

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 ...

Assaying the Kinase Activity of LRRK2 in vitro

Leucine Rich Repeat Kinase 2 (LRRK2) is a 2527 amino acid member of the ROCO family of proteins, possessing a complex, multidomain structure including a GTPase domain (termed ROC, for Ras of Complex proteins) and a kinase domain1. The discovery in 2004 of mutations in LRRK2 that cause Parkinson's disease (PD) resulted in LRRK2 being the focus of a huge volume of research into its normal function and how the protein goes awry in the disease state2,3. Initial investigations into the function of LRRK2 focused on its enzymatic activities4-6. Although a clear picture has yet to emerge of a consistent alteration in these due to mutations, data from a number of groups has highlighted the importance of the kinase activity of LRRK2 in cell death linked to mutations7,8. Recent publications have reported inhibitors targeting the kinase activity of LRRK2, providing a key experimental tool9-11. In light of these data, it is likely that the enzymatic properties of LRRK2 afford us an important window into the biology of this protein, although whether they are potential drug targets for Parkinson's is open to debate.
A number of different approaches have been used to assay the kinase activity of LRRK2. Initially, assays were carried out using epitope tagged protein overexpressed in mammalian cell lines and immunoprecipitated, with the assays carried out using this protein immobilised on agarose beads4,5,7. Subsequently, purified recombinant fragments of LRRK2 in solution have also been used, for example a GST tagged fragment purified from insect cells containing residues 970 to 2527 of LRRK212. Recently, Dani&euml;ls et al. reported the isolation of full length LRRK2 in solution from human embryonic kidney cells, however this protein is not widely available13. In contrast, the GST fusion truncated form of LRRK2 is commercially available (from Invitrogen, see table 1 for details), and provides a convenient tool for demonstrating an assay for LRRK2 kinase activity. Several different outputs for LRRK2 kinase activity have been reported. Autophosphorylation of LRRK2 itself, phosphorylation of Myelin Basic Protein (MBP) as a generic kinase substrate and phosphorylation of an artificial substrate - dubbed LRRKtide, based upon phosphorylation of threonine 558 in Moesin - have all been used, as have a series of putative physiological substrates including &alpha;-synuclein, Moesin and 4-EBP14-17. The status of these proteins as substrates for LRRK2 remains unclear, and as such the protocol described below will focus on using MBP as a generic substrate, noting the utility of this system to assay LRRK2 kinase activity directed against a range of potential substrates.

Assaying the Kinase Activity of LRRK2 in vitro

Leucine Rich Repeat Kinase 2 is a large multidomain kinase, mutations in which are the most common genetic cause of Parkinson's disease. Analysis of the kinase activity of this protein has proven to be a crucial tool in understanding the biology and dysfunction of this protein. In this paper, in vitro assaying of the kinase activity of LRRK2 and a selection of its mutants is described, providing an experimental system to examine phosphorylation of putative substrates and potential dysfunction of LRRK2 in disease.

LRRK2 Kinaz Aktivitesi Assaying In vitro</em

Leucine Rich Repeat Kinase 2 (LRRK2) is a 2527 amino acid member of the ROCO family of proteins, possessing a complex, multidomain structure including a ...

Isolation of Immune Cells from Primary Tumors

Tumors create a unique immunosuppressive microenvironment (tumor microenvironment, TME) whereby leukocytes are recruited into the tumor by various chemokines and growth factors 1,2. However, once in the TME, these cells lose the ability to promote anti-tumor immunity and begin to support tumor growth and down-regulate anti-tumor immune responses 3-4. Studies on tumor-associated leukocytes have mainly focused on cells isolated from tumor-draining lymph nodes or spleen due to the inherent difficulties in obtaining sufficient cell numbers and purity from the primary tumor. While identifying the mechanisms of cell activation and trafficking through the lymphatic system of tumor bearing mice is important and may give insight to the kinetics of immune responses to cancer, in our experience, many leukocytes, including dendritic cells (DCs), in tumor-draining lymph nodes have a different phenotype than those that infiltrate tumors 5,6 . Furthermore, we have previously demonstrated that adoptively-transferred T cells isolated from the tumor-draining lymph nodes are not tolerized and are capable of responding to secondary stimulation in vitro unlike T cells isolated from the TME, which are tolerized and incapable of proliferation or cytokine production 7,8. Interestingly, we have shown that changing the tumor microenvironment, such as providing CD4+ T helper cells via adoptive transfer, promotes CD8+ T cells to maintain pro-inflammatory effector functions 5. The results from each of the previously mentioned studies demonstrate the importance of measuring cellular responses from TME-infiltrating immune cells as opposed to cells that remain in the periphery. To study the function of immune cells which infiltrate tumors using the Miltenyi Biotech isolation system9, we have modified and optimized this antibody-based isolation procedure to obtain highly enriched populations of antigen presenting cells and tumor antigen-specific cytotoxic T lymphocytes. The protocol includes a detailed dissection of murine prostate tissue from a spontaneous prostate tumor model (TRansgenic Adenocarcinoma of the Mouse Prostate -TRAMP) 10 and a subcutaneous melanoma (B16) tumor model followed by subsequent purification of various leukocyte populations.

In this report, we describe a protocol for isolating highly purified populations of leukocytes that infiltrate tumors. This protocol is adapted from the Miltenyi Biotech protocol to enhance yield and purity for isolating cells from complex tumor tissue.

Primer Tümörler gelen Bağışıklık Hücre İzolasyonu

Tumors create a unique immunosuppressive microenvironment (tumor microenvironment, TME) whereby leukocytes are recruited into the tumor by various ...

A Semi-quantitative Approach to Assess Biofilm Formation Using Wrinkled Colony Development

Biofilms, or surface-attached communities of cells encapsulated in an extracellular matrix, represent a common lifestyle for many bacteria. Within a biofilm, bacterial cells often exhibit altered physiology, including enhanced resistance to antibiotics and other environmental stresses 1. Additionally, biofilms can play important roles in host-microbe interactions. Biofilms develop when bacteria transition from individual, planktonic cells to form complex, multi-cellular communities 2. In the laboratory, biofilms are studied by assessing the development of specific biofilm phenotypes. A common biofilm phenotype involves the formation of wrinkled or rugose bacterial colonies on solid agar media 3. Wrinkled colony formation provides a particularly simple and useful means to identify and characterize bacterial strains exhibiting altered biofilm phenotypes, and to investigate environmental conditions that impact biofilm formation. Wrinkled colony formation serves as an indicator of biofilm formation in a variety of bacteria, including both Gram-positive bacteria, such as Bacillus subtilis 4, and Gram-negative bacteria, such as Vibrio cholerae 5, Vibrio parahaemolyticus 6, Pseudomonas aeruginosa 7, and Vibrio fischeri 8.
The marine bacterium V. fischeri has become a model for biofilm formation due to the critical role of biofilms during host colonization: biofilms produced by V. fischeri promote its colonization of the Hawaiian bobtail squid Euprymna scolopes 8-10. Importantly, biofilm phenotypes observed in vitro correlate with the ability of V. fischeri cells to effectively colonize host animals: strains impaired for biofilm formation in vitro possess a colonization defect 9,11, while strains exhibiting increased biofilm phenotypes are enhanced for colonization 8,12. V. fischeri therefore provides a simple model system to assess the mechanisms by which bacteria regulate biofilm formation and how biofilms impact host colonization.
In this report, we describe a semi-quantitative method to assess biofilm formation using V. fischeri as a model system. This method involves the careful spotting of bacterial cultures at defined concentrations and volumes onto solid agar media; a spotted culture is synonymous to a single bacterial colony. This 'spotted culture' technique can be utilized to compare gross biofilm phenotypes at single, specified time-points (end-point assays), or to identify and characterize subtle biofilm phenotypes through time-course assays of biofilm development and measurements of the colony diameter, which is influenced by biofilm formation. Thus, this technique provides a semi-quantitative analysis of biofilm formation, permitting evaluation of the timing and patterning of wrinkled colony development and the relative size of the developing structure, characteristics that extend beyond the simple overall morphology.

We provide a simple, semi-quantitative method to investigate biofilm formation in vitro. This method takes advantage of the Zeiss stemi 2000-C Dissecting Microscope (with camera attachment) to monitor both the timing and pattern of biofilm formation, as assessed by the development of wrinkled colonies.

Buruşuk Koloni Gelişimi kullanarak Biyofilm Oluşumu değerlendirin Bir Yarı-kantitatif Yaklaşım

Biofilms, or surface-attached communities of cells encapsulated in an extracellular matrix, represent a common lifestyle for many bacteria. Within a ...

Endothelial Cell Tube Formation Assay for the In Vitro Study of Angiogenesis

Angiogenesis is a vital process for normal tissue development and wound healing, but is also associated with a variety of pathological conditions. Using this protocol, angiogenesis may be measured in vitro in a fast, quantifiable manner. Primary or immortalized endothelial cells are mixed with conditioned media and plated on basement membrane matrix. The endothelial cells form capillary like structures in response to angiogenic signals found in conditioned media. The tube formation occurs quickly with endothelial cells beginning to align themselves within 1&#160;hr and lumen-containing tubules beginning to appear within 2 hr. Tubes can be visualized using a phase contrast inverted microscope, or the cells can be treated with calcein AM prior to the assay and tubes visualized through fluorescence or confocal microscopy. The number of branch sites/nodes, loops/meshes, or number or length of tubes formed can be easily quantified as a measure of in vitro angiogenesis. In summary, this assay can be used to identify genes and pathways that are involved in the promotion or inhibition of angiogenesis in a rapid, reproducible, and quantitative manner.

Endothelial Cell Tube Formation Assay for the In Vitro Study of Angiogenesis

The tube formation assay is a fast, quantifiable method for measuring in vitro angiogenesis. Endothelial cells are combined with conditioned media and plated on basement membrane extract. Tube formation occurs within hours and newly formed tubules easily quantified.

Endotel Hücre için Tüp Deneyi birleşimi<em&gt; İn Vitro</em&gt; Anjiyogenezin Çalışması

Angiogenesis is a vital process for normal tissue development and wound healing, but is also associated with a variety of pathological conditions. Using ...

The Soft Agar Colony Formation Assay

Anchorage-independent growth is the ability of transformed cells to grow independently of a solid surface, and is a hallmark of carcinogenesis. The soft agar colony formation assay is a well-established method for characterizing this capability in vitro and is considered to be one of the most stringent tests for malignant transformation in cells. This assay also allows for semi-quantitative evaluation of this capability in response to various treatment conditions. Here, we will demonstrate the soft agar colony formation assay using a murine lung carcinoma cell line, CMT167, to demonstrate the tumor suppressive effects of two members of the Wnt signaling pathway, Wnt7A and Frizzled-9 (Fzd-9). Concurrent overexpression of Wnt7a and Fzd-9 caused an inhibition of colony formation in CMT167 cells. This shows that expression of Wnt7a ligand and its Frizzled-9 receptor is sufficient to suppress tumor growth in a murine lung carcinoma model.

The soft agar colony formation assay is a method used to confirm cellular anchorage-independent growth in vitro. The goal of this protocol is to illustrate a stringent method for the detection of the tumorigenic potential of transformed cells and the tumor suppressive effects of proteins on transformed cells.

Yumuşak Agar koloni formasyon deneyi

Anchorage-independent growth is the ability of transformed cells to grow independently of a solid surface, and is a hallmark of carcinogenesis. The soft ...

Quantitative Immunofluorescence Assay to Measure the Variation in Protein Levels at Centrosomes

Centrosomes are small but important organelles that serve as the poles of mitotic spindle to maintain genomic integrity or assemble primary cilia to facilitate sensory functions in cells. The level of a protein may be regulated differently at centrosomes than at other .cellular locations, and the variation in the centrosomal level of several proteins at different points of the cell cycle appears to be crucial for the proper regulation of centriole assembly. We developed a quantitative fluorescence microscopy assay that measures relative changes in the level of a protein at centrosomes in fixed cells from different samples, such as at different phases of the cell cycle or after treatment with various reagents. The principle of this assay lies in measuring the background corrected fluorescent intensity corresponding to a protein at a small region, and normalize that measurement against the same for another protein that does not vary under the chosen experimental condition. Utilizing this assay in combination with BrdU pulse and chase strategy to study unperturbed cell cycles, we have quantitatively validated our recent observation that the centrosomal pool of VDAC3 is regulated at centrosomes during the cell cycle, likely by proteasome-mediated degradation specifically at centrosomes.

Here, a novel quantitative fluorescence assay is developed to measure changes in the level of a protein specifically at centrosomes by normalizing that protein&#8217;s fluorescence intensity to that of an appropriate internal standard.

Kantitatif İmmünofloresan Deneyi sentrozomlar Protein Düzeyleri Varyasyon Tedbir

Centrosomes are small but important organelles that serve as the poles of mitotic spindle to maintain genomic integrity or assemble primary cilia to ...

In Vitro Assay to Measure Phosphatidylethanolamine Methyltransferase Activity

Phosphatidylethanolamine methyltransferases are biosynthetic enzymes that catalyze the transfer of one or more methyl group(s) from S-adenosyl-L-methionine onto phosphatidylethanolamine, monomethyl-phosphatidylethanolamine, or dimethyl-phosphatidylethanolamine to give either monomethyl-phosphatidylethanolamine, dimethyl-phosphatidylethanolamine or phosphatidylcholine. These enzymes are ubiquitous in animal cells, fungi, and are also found in approximately 10% of bacteria. They fulfill various important functions in cell physiology beyond their direct role in lipid metabolism such as in insulin resistance, diabetes, atherosclerosis, cell growth, or virulence. The present manuscript reports on a simple cell-free enzymatic assay that measures the transfer of tritiated methyl group(s) from S-[Methyl-3H]adenosyl-L-methionine onto phosphatidylethanolamine using whole cell extracts as an enzyme source. The resulting methylated forms of phosphatidylethanolamine are hydrophobic and thus, can be separated from water soluble S-[Methyl-3H]adenosyl-L-methionine by organic extraction. This assay can potentially be applied to any other cell types and used to test inhibitors/drugs specific to a phosphatidylethanolamine methyltransferase of interest without the need to purify the enzyme.

In Vitro Assay to Measure Phosphatidylethanolamine Methyltransferase Activity

The present report describes an in vitro enzymatic assay to measure phosphatidylethanolamine methyltransferase activity using Leishmania cell extracts. This assay is based on the transfer of a radioactive methyl group from S-[Methyl-3H]adenosyl-L-methionine onto endogenous phosphatidylethanolamine.

Tümör Hücrelerinin vaskülojenik Faaliyet değerlendirin bir Matrigel Tabanlı Tüp Oluşumu Testi

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