이 작품은 NCI R01 CA120659 (RS)에 의해 지원되었다.

1. 종양 세포의 Vasculogenic 활동을 평가 Matrigel 기반 튜브 형성 분석 <ol><li> 종양 세포 및 microvascular 내피 세포의 준비 같은 U87 세포, 흑색증 세포 B16F1, 유방 암 MDA - MB - 435, 그리고 결장 세포 HCT116과 같은 뇌 종양 세포는 (10 % FBS 및 페니실린 / 스트렙토 마이신과 보충 DMEM에서 재배되었다 Invitrogen에서 ). 내피 세포주 인간 microvascular 내피 세포 (HMVECs은) 1 μg / ML 하이드로코티손 1 NG / ML 표피 성장 인자 10 % FBS 및 페니실린 / 스트렙토 마이신과 보충 EBM2 중간 (Lonza)에 교양되었습니다. 세포는 PBS로 세 번 씻어와 0.05 % 트립신 / EDTA (에틸렌 다이아 민 테트라 초산) (Invitrogen)로 분리되었다. 5 분 2,000 RPM과 원심 분리 후 세포 펠렛은 PBS로 다시 씻어되었습니다. 그런 다음 pelleted 전지는 hemocytometer로 집계되었다. </li><li> Matrigel 준비 : 성장 인자 - 나누어지는 감소 Matrigel이 (BD Bioscience) 실온에서 예열했다. 완전히 해동되기 전에, 그것은 얼음에 양도했고 그 액체는 적어도 10 분 얼음에 보관했다. 다음 Matrigel 50 μl가 Matrigel가 균일하게 배포 수있는 수평 레벨에서 96 - 웰 플레이트에 도금 및 37 ° C. 30 분 incubated되었습니다 </li><li> 튜브 형성 : 세포 (1-2 X 10 4)이 내피 세포 종양 세포 또는 EBM - 2 혈청 무료 DMEM으로 다시 중단하고, Matrigel의 위에 적재했다. 이 분석은 가느다란 관 개발에 일부 요원들의 효과를 측정에 사용되는 경우,이 요원 (stimulators 또는 억제제)은 혈청이없는 매체에 추가되었습니다. 각 조건 그룹은 4-6 우물이 포함되어 있습니다. </li><li> 이미지 및 데이터 분석 : 37에서 다음과 부화 ° C 야간 각 잘가 현미경으로 직접 분석했다. tubules가 고정에 필요한이라면 10 % 포르말린 생리 기반 솔루션 100 μl가 부드럽게 추가되었습니다 십 분 후, 분석을 위해 준비했습니다. 10X 위상 대조 현미경, 각 분야의 tubules이 몇 군데 있었다 각 우물에 3-5 임의의 분야에서 tubules의 평균이 계산되었습니다. </li></ol> 2. 대표 결과 : 이러한 tubules가 다각형 네트워크를 형성 연결 명확한 길쭉한 세포 기관에서 개발된 것처럼 HMVECs은 긍정적인 제어로 사용되었습니다. B16F1, U87, 그리고 MDA - MB - 435 세포에 의해 형성 HMVECs 비슷한 혈관 tubules을 개발하지만, HCT116 세포는 (그림 1)하지 않았다. 세포 투여량에 의존 튜브 형성 U87 세포에서 테스트되었습니다. 그림 2에서 보여주 10,000 전지는 중단 tubules을 형성. 세포가 두 배가되었습니다되면 고체 혈관 네트워크 HMVECs에서 본 것과 비교했다. 대조적으로, 5,000 이하 세포는 혈관 표현형를 형성하지 못했습니다. <img src="/files/ftp_upload/3040/3040fig1.jpg" alt="그림 1"/> 그림 1. HMVECs, U87, MDA - MB - 435과 B16F1 세포에 의해 유도하지만, HCT116 세포. 모든 세포는 (2 × 10 4) Matrigel에 적재하고 하룻밤 incubated되지 않았습니다 튜브 형성. Tubules는 위상 콘트라스트를 사용하여 몇 군데 있었다. HMVECs은 긍정적인 제어로 사용되었습니다. 3-5 분야의 대표가 표시되었다. 바 : 100 μm의. <img src="/files/ftp_upload/3040/3040fig2.jpg" alt="그림 2"/> 휴대폰 번호 종속적인 방식으로 그림 2. U87 세포 유발 tubules.로서 모서리에 표시된 U87 세포의 서로 다른 숫자는 튜브 형성을 위해 사용되었습니다. HMVECs은 긍정적인 제어에 사용되었다. 바 : 100mm.

<ol>
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관심 없음 충돌 선언하지 않습니다.

성공이 분석하기 위해서, Matrigel의 품질 먼저 테스트해야합니다. 작은 샘플 HMVECs를 사용하여 분석을 미리 실행 Bioscience BD에서 구할 수 있습니다. 다른 배치 제품은 일부 많은 튜브 형성을위한 최적의 조건을 제공하지 않는에 ...와 비슷하지 않은 자질을 표시할 수 있습니다. Matrigel의 나누어지는가 96 - 웰 플레이트에 로드할 때 거품이 가느다란 관 형성을 방해 할 수 있기 때문에 둘째, 모든 거품은 ...

<table border="1"><tbody><tr><th> 시약의 이름 </th><th> 회사 </th><th> 카탈로그 번호 </th></tr><tr><td> DMEM </td><td> Invitrogen </td><td> 11,995 </td></tr><tr><td> FBS </td><td> Invitrogen </td><td> 16000-044 </td></tr><tr><td> 성장 인자 - 할인 Matrigel </td><td> Bioscience BD </td><td> 47743-720 </td></tr><tr><td> EBM2 키트 </td><td> Lonza </td><td> CC - 3156 </td></tr><tr><td> 니콘 이클립스 TS100 현미경 </td><td> 니콘 </td><td></td></tr></tbody></table>

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

지난 몇 년간, 튜브 형성 분석 성장을 사용하는 인자 - 감소 Matrigel 일반적으로 체외 1-5에서 혈관 내피 세포의 angiogenic 활동을 입증하기 위해 채용되었습니다. 그러나, 최근에 성장 증거는이 분석은 내피 세포에 대한 혈관 동작을 테스트하기 위해 제한 아니라는 것을 보여주었다. 대신, 그것은 또한 혈관 표현형 6-8을 개발하는 종양 세포의 숫자의 능력을 테스트하는 데 사용되었습니다. 이 기능은 xenotransplanted 동물, vasculogenic 흉내 (VM) 9라는 과정에서 확인된 그들의 vasculogenic 행동과 일치했다. 그 종양 세포 매개의 VM이 내피 세포 angiogenesis 6, 10-13의 독립 종양 개발에 중요한 역할을 보여주는 증거 다수가있다. 예를 들어, 종양 세포는 흑색증 및 glioblastoma 환자 8, 10, 11 조직 샘플에서 혈액 perfused, 혈관 채널 형성에 참여하는 발견되었습니다. 여기, 우리는 종양 세포의 vasculogenic 활동의 평가에 유용한 도구로 관형 네트워크 분석을 설명했다. 우리는 이러한 흑색증 B16F1 세포, glioblastoma U87 세포와 유방암 MDA - MB - 435 세포와 같은 일부 종양 세포 라인 혈관 tubules를 형성 할 수있다는 사실을 발견했다,하지만 일부는 결장암 HCT116 세포와 같은하지 않습니다. 또한,이 혈관 표현형는 Matrigel에 도금 휴대폰 번호에 따라 좌우됩니다. 따라서이 분석은 혈관 세포, 종양 세포뿐만 아니라 다른 세포를 포함한 세포 유형의 다양한 혈관 가능성을 화면에 강력한 유틸리티로 사용될 수 있습니다.

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

튜브 형성 분석은 종양 세포의 혈관 활동을 평가하는 데 사용됩니다.

종양 세포의 Vasculogenic 활동을 평가 Matrigel 기반 튜브 형성 분석

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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65.9K 조회수.  University of Massachusetts. 튜브 형성 분석은 종양 세포의 혈관 활동을 평가하는 데 사용됩니다.

비디오: 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.

의 활동을 측정하는 어세이 대장균은 라이신 Decarboxyase을 Inducible

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 ...

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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 분석 : 자기편 셀

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

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.

일차 종양에서 면역 세포의 분리

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.

주름 식민지 개발을 사용하여 Biofilm 형성을 평가하기 위해 세미 양적 접근

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.

에 대한 내피 세포의 관 형성의 분석<em&gt; 체외</em&gt; 혈관 신생 연구

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.

소프트 한천 콜로니 형성 분석

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.

정량 면역 형광 분석은 중심체에서 단백질 수준의 변화를 측정하기 위해

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.

시험 관내 분석에서 포스파티딜 메틸화 된 역가를 측정하는 방법

Phosphatidylethanolamine methyltransferases are biosynthetic enzymes that catalyze the transfer of one or more methyl group(s) from ...

Nephrotoxin Microinjection in Zebrafish to Model Acute Kidney Injury

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid decline in renal function and development of the clinical syndrome known as acute kidney injury (AKI). Pharmacological agents used to treat medical circumstances ranging from bacterial infection to cancer, when administered individually or in combination with other drugs, can initiate AKI. Zebrafish are a useful animal model to study the chemical effects on renal function in vivo, as they form an embryonic kidney comprised of nephron functional units that are conserved with higher vertebrates, including humans. Further, zebrafish can be utilized to perform genetic and chemical screens, which provide opportunities to elucidate the cellular and molecular facets of AKI and develop therapeutic strategies such as the identification of nephroprotective molecules. Here, we demonstrate how microinjection into the zebrafish embryo can be utilized as a paradigm for nephrotoxin studies.

Renal injuries incurred from nephrotoxins, which include drugs ranging from antibiotics to chemotherapeutics, can result in complex disorders whose pathogenesis remains incompletely understood. This protocol demonstrates how zebrafish can be used for disease modeling of these conditions, which can be applied to the identification of renoprotective measures.

Zebrafish의에서 콩팥 세포 독소 미세 주입은 급성 신장 손상을 모델링하기

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid ...

A Method to Assess Bacteriocin Effects on the Gut Microbiota of Mice

Very intriguing questions arise with our advancing knowledge on gut microbiota composition and the relationship with health, particularly relating to the factors that contribute to maintaining the population balance. However, there are limited available methodologies to evaluate these factors. Bacteriocins are antimicrobial peptides produced by many bacteria that may confer a competitive advantage for food acquisition and/or niche establishment. Many probiotic lactic acid bacteria (LAB) strains have great potential to promote human and animal health by preventing the growth of pathogens. They can also be used for immuno-modulation, as they produce bacteriocins. However, the antagonistic activity of bacteriocins is normally determined by laboratory bioassays under well-defined but over-simplified conditions compared to the complex gut environment in humans and animals, where bacteria face multifactorial influences from the host and hundreds of microbial species sharing the same niche. This work describes a complete and efficient procedure to assess the effect of a variety of bacteriocins with different target specificities in a murine system. Changes in the microbiota composition during the bacteriocin treatment are monitored using compositional 16S rDNA sequencing. Our approach uses both the bacteriocin producers and their isogenic non-bacteriocin-producing mutants, the latter giving the ability to distinguish bacteriocin-related from non-bacteriocin-related modifications of the microbiota. The fecal DNA extraction and 16S rDNA sequencing methods are consistent and, together with the bioinformatics, constitute a powerful procedure to find faint changes in the bacterial profiles and to establish correlations, in terms of cholesterol and triglyceride concentration, between bacterial populations and health markers. Our protocol is generic and can thus be used to study other compounds or nutrients with the potential to alter the host microbiota composition, either when studying toxicity or beneficial effects.

Bacteriocins are believed to play a key role in defining microbial diversity in different ecological niches. Here, we describe an efficient procedure to assess how bacteriocins affect gut microbiota composition in an animal model.

마우스의 장내 미생물에 대한 박테리오신 효과 평가 방법

Very intriguing questions arise with our advancing knowledge on gut microbiota composition and the relationship with health, particularly relating to the ...