Name: a new clarification method to visualize biliary degeneration during liver metamorphosis in sea lamprey (petromyzon marinus)
Uploaded: 2014-06-06T14:15:00
Description: Watch this Scientific Journal Video about A New Clarification Method to Visualize Biliary Degeneration During Liver Metamorphosis in Sea Lamprey Petromyzon marinus at JoVE.com

The authors acknowledge the contribution of Hammond Bay Biological Station, Great Lakes Science Center, U.S. Geological Survey. We also thank Dr. Melinda Frame at the Center for Advanced Microscopy at Michigan State University for her technical support in laser scanning confocal microscopy. This study is supported by grants from the Great Lakes Fishery Commission to YWCD and WML.

1. Solution Preparation
<ol>
	<li>Make 1 L 10x 0.1 M phosphate buffer saline (PBS, pH 7.4): Weigh 26.2 g sodium phosphate (monobasic), 115 g sodium phosphate (dibasic), and 87.66 g NaCl. Dissolve in about 800 ml distilled H2O, adjust pH, and bring the volume up to 1 L with distilled H2O.
	<ol>
		<li>Make 1 L 0.1 M phosphate buffer saline (pH 7.4): Take 100 ml 10x PBS, and add 900 ml distilled H2O.</li>
		<li>Make 1 L 0.1 M phosphate buffer saline (pH 7.4) with 0.1% Triton X-100: Take 10...

<ol>
	<li>Applegate, V. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Natural+history+of+the+sea+lamprey+(Petromyzon+marinus)+in+Michigan.">Natural history of the sea lamprey (Petromyzon marinus) in Michigan.</a> US Fish and Wildlife Service Special Science Report on Fishery Service. (55), (1950).</li><li>Hardisty, M. W., Potter, I. C., Hardisty, M. W., Potter, I. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+general+biology+of+adult+lampreys.">The general biology of adult lampreys.</a> The biology of lampreys. 1, 127-206 (1971).</li><li>Youson, J. H., Potter, I. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+description+of+the+stages+in+the+metamorphosis+of+the+anadromous+sea+lamprey,+Petromyzon+marinus+L.">A description of the stages in the metamorphosis of the anadromous sea lamprey, Petromyzon marinus L.</a> Can. J. Zool. 57, 1808-1817 (1979).</li><li>Boomer, L. 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=Cholangiocyte+apoptosis+is+an+early+event+during+induced+metamorphosis+in+the+sea+lamprey,+Petromyzon+marinus+L.">Cholangiocyte apoptosis is an early event during induced metamorphosis in the sea lamprey, Petromyzon marinus L.</a> J. Pediatr. Surg. 45, 114-120 (2010).</li><li>Kasai, M., Suzuki, H., Ohashi, E., Ohi, R., Chiba, T., Okamoto, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Technique+and+results+of+operative+management+of+biliary+atresia.">Technique and results of operative management of biliary atresia.</a> World J. Surg. 2, 571-580 (1978).</li><li>Suzuki, T., Hashimoto, T., Kondo, S., Sato, Y., Hussein, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluating+patients&#8217;+outcome+post-Kasai+operation:+a+19-year+experience+with+modification+of+the+hepatic+portoenterostomy+and+applying+a+novel+steroid+therapy+regimen.">Evaluating patients&#8217; outcome post-Kasai operation: a 19-year experience with modification of the hepatic portoenterostomy and applying a novel steroid therapy regimen.</a> Pediatr. Surg. Int. 26, 825-830 (2010).</li><li>Hartley, J. L., Davenport, M., Kelly, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biliary+atresia.">Biliary atresia.</a> Lancet. 374, 1704-1713 (2009).</li><li>Morecki, R., Glaser, J. H., Cho, S., Balistreri, W. F., Horwitz, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biliary+atresia+and+reovirus+type+3+infection.">Biliary atresia and reovirus type 3 infection.</a> New Engl. J. Med. 307, 481-484 (1982).</li><li>Shimadera, S., Iwai, N., Deguchi, E., Kimura, O., Fumino, S., Yokoyama, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+inv+mouse+as+an+experimental+model+of+biliary+atresia.">The inv mouse as an experimental model of biliary atresia.</a> J. Pediatr. Surg. 42, 1555-1560 (2007).</li><li>Sidon, E. W., Youson, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphological+changes+in+the+liver+of+the+sea+lamprey,+Petromyzon+marinus+L.,+during+metamorphosis:+I.+Atresia+of+the+bile+ducts.">Morphological changes in the liver of the sea lamprey, Petromyzon marinus L., during metamorphosis: I. Atresia of the bile ducts.</a> J. Morphol. 177, 109-124 (1983).</li><li>Yeh, C. -. Y., Chung-Davidson, Y. -. W., Wang, H., Li, K., Li, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intestinal+synthesis+and+secretion+of+bile+salts+as+an+adaptation+to+developmental+biliary+atresia+in+the+sea+lamprey.">Intestinal synthesis and secretion of bile salts as an adaptation to developmental biliary atresia in the sea lamprey.</a> Proc. Nat. Acad. Sci. U.S.A. 109, 11419-11424 (2012).</li><li>Chung, K., 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=Structural+and+molecular+interrogation+of+intact+biological+systems.">Structural and molecular interrogation of intact biological systems.</a> Nature. 497, 332-337 (2013).</li><li>Alarc&#243;n, V. B., Filosa, M. F., Youson, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cytokeratins+in+the+liver+of+the+sea+lamprey+(Petromyzon+marinus)+before+and+after+metamorphosis.">Cytokeratins in the liver of the sea lamprey (Petromyzon marinus) before and after metamorphosis.</a> Cell Tissue Res. 287, 365-374 (1997).</li><li>Youson, J. H., Ogilvie, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrastructural+features+of+degeneration+of+the+gallbladder+during+lamprey+biliary+atresia.">Ultrastructural features of degeneration of the gallbladder during lamprey biliary atresia.</a> Tissue and Cell. 22, 477-492 (1990).</li><li>Morii, M., 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=Onset+of+apoptosis+in+the+cystic+duct+during+metamorphosis+of+a+Japanese+lamprey,+Lethenteron+reissneri.">Onset of apoptosis in the cystic duct during metamorphosis of a Japanese lamprey, Lethenteron reissneri.</a> Anat. Rec. 293, 1155-1166 (2010).</li></ol>

This protocol is modified from a new method called &#8220;CLARITY&#8221;12, which crosslinks intact tissue with polyacrylamide to form a nanoporous hydrogel, and then strips away the plasma membrane of the tissue to achieve optical transparency and macromolecular permeability. &#8220;CLARITY&#8221; allows intact-tissue imaging of long-range projection and local circuit wiring in the nervous system. This new method can be used to visualize the entire biliary system in sea lamprey liver during metamorphosis. It ...

Sea lamprey develop through three distinct life stages1,2. Larval sea lamprey (L) spend most time in burrows as benthic filter feeders. After going through seven metamorphic stages of dramatic changes in external morphology and reorganization in internal organs3, the resulting juveniles (JV) enter a parasitic stage during which they feed on blood and tissue fluids from host fish, increasing the body mass more than 100 times. After 1.0 to 1.5 years feeding on the host fish in the ocean or large lakes, adults cease feeding during the early spring and migrate into rivers to spawn and then die1,2.

During metamorphosis, the sea lamprey liver loses the gall bladder and the entire biliary tree, an evolutionary mutant phenotype that mimics the human infant disease biliary atresia. Infant biliary atresia is a rare pediatric liver disease with severe medical complications4,5,6,7,8,9,10, however the pathogenesis and etiology of biliary atresia are largely unknown4. Patients with biliary atresia die within two years after birth unless surgical intervention (Kasai procedure) is performed5. Subsequently, these patients require extensive clinical management and often liver transplantation&#160;6. Many theories of biliary atresia etiopathogenesis have been proposed, such as viral infection, congenital malformation, autoimmune disease, and toxic insult. However, the contribution of each to the development of biliary atresia remains inconclusive7,8,9,10.

Unlike infants that suffer pathological biliary atresia, sea lamprey undergo developmentally programmed biliary atresia without extensive necroinflammation, fibrosis or cirrhosis10. The animals may suffer transient cholestasis during this process10, but adapt to this developmental condition via de novo synthesis and secretion of bile salts in the intestine after developmental biliary atresia, in addition to known mechanisms such as reduction of bile salt synthesis in liver11. This developmental process in sea lamprey provides the only known opportunity to examine the progression of biliary atresia.

A newly-developed method called &#8220;CLARITY&#8221; enables high-resolution imaging in complex mammalian nervous systems by transforming intact tissue into an optically transparent nanoporous hydrogel12. Using sea lamprey liver and a modified CLARITY protocol, intact-tissue imaging of biliary degeneration can be documented throughout liver metamorphosis.

<table border="0" cellpadding="0" cellspacing="0" width="702">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">40% acrylamide&#160;</td>
			<td style="width:200px;">Bio-Rad</td>
			<td style="width:119px;">161-0140</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2% bis-acrylamide&#160;</td>
			<td>Bio-Rad</td>
			<td>161-0142</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">TEMED</td>
			<td>Bio-Rad</td>
			<td>161-0800</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">ammonium persulfate&#160;</td>
			<td>Sigma</td>
			<td>A3678-25G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">boric acid</td>
			<td>Sigma</td>
			<td>B7901-1KG</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">saponin&#160;</td>
			<td>Sigma</td>
			<td>47036</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">sodium dodecyl sulfate&#160;</td>
			<td>Sigma</td>
			<td style="width:119px;">L337-500G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">sodium phosphate (monobasic)</td>
			<td>Sigma</td>
			<td>04269-1KG</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">sodium phosphate (dibasic)</td>
			<td>Sigma</td>
			<td>S5136-1KG</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Triton X-100</td>
			<td>Sigma</td>
			<td>X100-500ML</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">glycerol&#160;</td>
			<td>Sigma</td>
			<td>G9012-500ML</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">16% paraformaldehyde&#160;</td>
			<td>Electron Microscopy Sciences</td>
			<td>15710-S</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">NaOH pellets&#160;</td>
			<td>EMD</td>
			<td>SX0590-3</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">15 ml centrifuge tubes</td>
			<td style="width:200px;">Any brand</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">dissecting tools&#160;</td>
			<td style="width:200px;">Any brand</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

a new clarification method to visualize biliary degeneration during liver metamorphosis in sea lamprey (petromyzon marinus)

Biliary atresia is a rare disease of infancy, with an estimated 1 in 15,000 frequency in the southeast United States, but more common in East Asian countries, with a reported frequency of 1 in 5,000 in Taiwan. Although much is known about the management of biliary atresia, its pathogenesis is still elusive. The sea lamprey (Petromyzon marinus) provides a unique opportunity to examine the mechanism and progression of biliary degeneration. Sea lamprey develop through three distinct life stages: larval, parasitic, and adult. During the transition from larvae to parasitic juvenile, sea lamprey undergo metamorphosis with dramatic reorganization and remodeling in external morphology and internal organs. In the liver, the entire biliary system is lost, including the gall bladder and the biliary tree. A newly-developed method called &#8220;CLARITY&#8221; was modified to clarify the entire liver and the junction with the intestine in metamorphic sea lamprey. The process of biliary degeneration was visualized and discerned during sea lamprey metamorphosis by using laser scanning confocal microscopy. This method provides a powerful tool to study biliary atresia in a unique animal model.

Several important developmental events occur in the hepatobiliary system during sea lamprey metamorphosis. The bile duct and the gall bladder undergo apoptosis and degenerate (Figure 1). Combining the modified clarification method and staining with liver cell marker cytokeratin 19 (CK19, present in both cholangiocytes and hepatocytes before and after metamorphosis13) and anti-apoptotic marker Bcl2 using confocal microscopy, the entire biliary system was captured along the Z-axis (Figur...

Watch this Scientific Journal Video about A New Clarification Method to Visualize Biliary Degeneration During Liver Metamorphosis in Sea Lamprey Petromyzon marinus at JoVE.com

A New Clarification Method to Visualize Biliary Degeneration During Liver Metamorphosis in Sea Lamprey Petromyzon marinus

Sea lamprey lose the gall bladder and bile ducts during metamorphosis, a process similar to human biliary atresia. A new fixation and clarification method (CLARITY) was modified to visualize the entire biliary tree using laser scanning confocal microscopy. This method provides a powerful tool to study biliary degeneration.

A New Clarification Method to Visualize Biliary Degeneration During Liver Metamorphosis in Sea Lamprey (Petromyzon marinus)

Biliary atresia is a rare disease of infancy, with an estimated 1 in 15,000 frequency in the southeast United States, but more common in East Asian ...

a-new-clarification-method-to-visualize-biliary-degeneration-during

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Biology

Pyrosequencing: A Simple Method for Accurate Genotyping

Pharmacogenetic research benefits first-hand from the abundance of information provided by the completion of the Human Genome Project. With such a tremendous amount of data available comes an explosion of genotyping methods. Pyrosequencing(R) is one of the most thorough yet simple methods to date used to analyze polymorphisms. It also has the ability to identify tri-allelic, indels, short-repeat polymorphisms, along with determining allele percentages for methylation or pooled sample assessment. In addition, there is a standardized control sequence that provides internal quality control. This method has led to rapid and efficient single-nucleotide polymorphism evaluation including many clinically relevant polymorphisms. The technique and methodology of Pyrosequencing is explained.


Pyrosequencing(R) is one of the most thorough yet simple methods to date used to analyze polymorphisms. This method has led to rapid and efficient single-nucleotide polymorphism evaluation including many clinically relevant polymorphisms. The technique and methodology of Pyrosequencing is explained.

Pharmacogenetic research benefits first-hand from the abundance of information provided by the completion of the Human Genome Project. With such a ...

Method for Culture of Early Chick Embryos ex vivo (New Culture)

The chick embryo is a valuable tool in the study of early embryonic development. Its transparency, accessibility and ease of manipulation, make it an ideal tool for studying  the formation and patterning of brain, neural tube, somite and heart primordia. Applications of chick embryo culture include electroporation of DNA or RNA constructs in order to analyze gene function, grafts of growth factor coated beads such as FGFs and BMPs , as well as whole mount in situ hybridization and immunohistochemistry. This video demonstrates the different steps in chick embryo culture; First, the embryo is explanted in saline. Then, the embryo is centered on a glass ring. The membranes surrounding the embryo are lifted along the walls of the ring. The ring is then placed in a culture dish containing a pool of albumine. The culture dish is sealed and placed in a humid chamber, where the embryo is cultured for up to 24 hrs. Finally, the embryo is removed from the ring, fixed and processed for further applications. A troubleshooting guide is also presented.

Method for Culture of Early Chick Embryos ex vivo New Culture

This video demonstrates New culture, a method by which chick embryos are cultured outside the egg for up to 24 hr. This method enables one to study early development (primitive streak to 14 som.), a period corresponding to E7-9 in mouse. Applications of this technique include electroporation, in situ hybridization and immunohistochemistry.

The chick embryo is a valuable tool in the study of early embryonic development. Its transparency, accessibility and ease of manipulation, make it an ...

Use of Time Lapse Microscopy to Visualize Anoxia-induced Suspended Animation in C. elegans Embryos

Caenorhabdits elegans has been used extensively in the study of stress resistance, which is facilitated by the transparency of the adult and embryo stages as well as by the availability of genetic mutants and transgenic strains expressing a myriad of fusion proteins1-4. In addition, dynamic processes such as cell division can be viewed using fluorescently labeled reporter proteins. The study of mitosis can be facilitated through the use of time-lapse experiments in various systems including intact organisms; thus the early C. elegans embryo is well suited for this study. Presented here is a technique by which in vivo imaging of sub-cellular structures in response to anoxic (99.999% N2; &lt;2 ppm O2) stress is possible using a simple gas flow through setup on a high-powered microscope. A microincubation chamber is used in conjunction with nitrogen gas flow through and a spinning disc confocal microscope to create a controlled environment in which animals can be imaged in vivo. Using GFP-tagged gamma tubulin and histone, the dynamics and arrest of cell division can be monitored before, during and after exposure to an oxygen-deprived environment. The results of this technique are high resolution, detailed videos and images of cellular structures within blastomeres of embryos exposed to oxygen deprivation.

Use of Time Lapse Microscopy to Visualize Anoxia-induced Suspended Animation in C. elegans Embryos

Described here is an in vivo technique to image sub-cellular structures in animals exposed to anoxia using a gas flow through microincubation chamber in conjunction with a spinning disc confocal microscope. This method is straightforward and flexible enough to suit a variety of experimental parameters and model systems.

Caenorhabdits elegans has been used extensively in the study of stress resistance, which is facilitated by the transparency of the adult and embryo stages ...

High Throughput Microinjections of Sea Urchin Zygotes

Microinjection into cells and embryos is a common technique that is used to study a wide range of biological processes. In this method a small amount of treatment solution is loaded into a microinjection needle that is used to physically inject individual immobilized cells or embryos. Despite the need for initial training to perform this procedure for high-throughput delivery, microinjection offers maximum efficiency and reproducible delivery of a wide variety of treatment solutions (including complex mixtures of samples) into cells, eggs or embryos. Applications to microinjections include delivery of DNA constructs, mRNAs, recombinant proteins, gain of function, and loss of function reagents. Fluorescent or colorimetric dye is added to the injected solution to enable instant visualization of efficient delivery as well as a tool for reliable normalization of the amount of the delivered solution. The described method enables microinjection of 100-400 sea urchin zygotes within 10-15 min.

Microinjection is a common technique used to deliver DNA constructs, mRNAs, morpholino antisense oligonucleotides or other treatments into eggs, embryos, and cells of various species.

Microinjection into cells and embryos is a common technique that is used to study a wide range of biological processes. In this method a small amount of ...

A Method for Extracting Pigments from Squid Doryteuthis pealeii

Cephalopods can undergo rapid and adaptive changes in dermal coloration for sensing, communication, defense, and reproduction purposes. These capabilities are supported in part by the areal expansion and retraction of pigmented organs known as chromatophores. While it is known that the chromatophores contain a tethered network of pigmented granules, their structure-function properties have not been fully detailed. We describe a method for isolating the nanostructured granules in squid Doryteuthis pealeii chromatophores and demonstrate how their associated pigments can be extracted in acidic solvents. To accomplish this, the chromatophore containing dermal layer is first manually isolated using a superficial dissection, and the pigment granules are removed using sonication, centrifugation, and washing cycles. Pigments confined within the purified granules are then extracted via acidic methanol solutions, leaving nanostructures with smaller diameters that are void of visible color. This extraction procedure produces a 58% yield of soluble pigments isolated from granules. Using this method, the composition of the chromatophore pigments can be determined and used to provide insight into the mechanism of adaptive coloration in cephalopods.

A Method for Extracting Pigments from Squid Doryteuthis pealeii

A protocol for the extraction of pigments from the nanostructured granules in squid Doryteuthis pealeii chromatophores is presented.

Cephalopods can undergo rapid and adaptive changes in dermal coloration for sensing, communication, defense, and reproduction purposes. These capabilities ...

Using a Whole-mount Immunohistochemical Method to Study the Innervation of the Biliary Tract in Suncus murinus

This work describes the whole-mount immunohistochemistry staining method in detail, using neurofilament protein antibody to label the innervation of the biliary tract in Suncus murinus (S. murinus&#160;). First, the specimen was dissected from S. murinus and fixed in 4% paraformaldehyde (PFA). Second, an enzymatic treatment and potential endogenous peroxidase inactivation were performed. The specimen was then exposed to the primary antibody, anti-neurofilament protein antibody, for 3-6 days. It was then incubated with the secondary antibody conjugated with horseradish peroxidase. The color reaction was revealed by reacting the specimen with a 3,3&#39;-diaminobenzidine (DAB) substrate. This method can be applied to analyze the innervation of all visceral organs. Furthermore, this protocol can also be adapted to test other neuronal antibodies, but optimization of the antibodies should be done first. This method was originally introduced by Kuratani and Tanaka1,2,3.

Using a Whole-mount Immunohistochemical Method to Study the Innervation of the Biliary Tract in Suncus murinus

A whole-mount immunohistochemical approach, to visualize neurofilament protein expression in the extrahepatic biliary tract in Suncus murinus. is presented here. This protocol can be used to analyze the innervation of all visceral organs in S. murinus or other species.

This work describes the whole-mount immunohistochemistry staining method in detail, using neurofilament protein antibody to label the innervation of the ...

Broth Microdilution In Vitro Screening: An Easy and Fast Method to Detect New Antifungal Compounds

Fungal infections have become an important medical condition in the last decades, but the number of available antifungal drugs is limited. In this scenario, the search for new antifungal drugs is necessary. The protocol reported here details a method to screen peptides for their antifungal properties. It is based on the broth microdilution susceptibility test from the Clinical and Laboratory Standards Institute (CLSI) M27-A3 guidelines with modifications to suit the research of antimicrobial peptides as potential new antifungals. This protocol describes a functional assay to evaluate the activity of antifungal compounds and may be easily modified to suit any particular class of molecules under investigation. Since the assays are performed in 96-well plates using small volumes, a large-scale screening can be completed in a short amount of time, especially if carried out in an automation setting. This procedure illustrates how a standardized and adjustable clinical protocol can help the bench-work pursuit of new molecules to improve the therapy of fungal diseases.

Broth Microdilution In Vitro Screening: An Easy and Fast Method to Detect New Antifungal Compounds

An easy and adaptable broth microdilution method for screening antifungal compounds and extracts.

Fungal infections have become an important medical condition in the last decades, but the number of available antifungal drugs is limited. In this ...

Split Green Fluorescent Protein System to Visualize Effectors Delivered from Bacteria During Infection

Bacteria, one of the most important causative agents of various plant diseases, secrete a set of effector proteins into the host plant cell to subvert the plant immune system. During infection cytoplasmic effectors are delivered to the host cytosol via a type III secretion system (T3SS). After delivery into the plant cell, the effector(s) targets the specific compartment(s) to modulate host cell processes for survival and replication of the pathogen. Although there has been some research on the subcellular localization of effector proteins in the host cells to understand their function in pathogenicity by using fluorescent proteins, investigation of the dynamics of effectors directly injected from bacteria has been challenging due to the incompatibility between the T3SS and fluorescent proteins.
Here, we describe our recent method of an optimized split superfolder green fluorescent protein system (sfGFPOPT) to visualize the localization of effectors delivered via the bacterial T3SS in the host cell. The sfGFP11 (11th &#946;-strand of sfGFP)-tagged effector secreted through the T3SS can be assembled with a specific organelle targeted sfGFP1-10OPT (1-10th &#946;-strand of sfGFP) leading to fluorescence emission at the site. This protocol provides a procedure to visualize the reconstituted sfGFP fluorescence signal with an effector protein from Pseudomonas syringae in a particular organelle in the Arabidopsis and Nicotiana benthamiana plants.

Fluorescent protein-based approaches to monitor effectors secreted by bacteria into host cells are challenging. This is due to the incompatibility between fluorescent proteins and the type-III secretion system. Here, an optimized split superfolder GFP system is used for visualization of effectors secreted by bacteria into the host plant cell.

Bacteria, one of the most important causative agents of various plant diseases, secrete a set of effector proteins into the host plant cell to subvert the ...

Immunolabelling Myofiber Degeneration in Muscle Biopsies

The necrosis of muscle fibres (myonecrosis) plays a central role in the pathogenesis of several muscle conditions, including muscular dystrophies. Therapeutic options addressing the causes of muscular dystrophy pathogenesis are expected to alleviate muscle degeneration. Therefore, a method to assay and quantify the extent of cell death in muscle biopsies is needed. Conventional methods to observe myofiber degeneration in situ are either poorly quantitative or rely on the injection of vital dyes. In this article, an immunofluorescence protocol is described that stains necrotic myofibers by targeting immunoglobulin G (IgG) uptake by myofibers. The IgG uptake method is based on cell features characterizing the necrotic demise, including 1) the loss of plasma membrane integrity with the release of damage-associated molecular patterns and 2) the uptake of plasmatic proteins. In murine cross-sections, the co-immunolabelling of myofibers, extracellular matrix proteins, and mouse IgG allows clean and straightforward identification of myofibers with necrotic fate. This simple method is suitable for quantitative analysis and applicable to all species, including human samples, and does not require the injection of vital dye. The staining of necrotic myofibers by IgG uptake can also be paired with other co-immunolabelling.

Described here is a protocol for direct immunolabelling of necrotic myofibers in muscle cryosections. Necrotic cells are permeable to serum proteins, including immunoglobulin G (IgG). Revealing the uptake of IgG by myofibers allows the identification and quantification of myofibers that undergo necrosis regardless of muscle condition.

The necrosis of muscle fibres (myonecrosis) plays a central role in the pathogenesis of several muscle conditions, including muscular dystrophies. ...

Apoptosis Induction and Detection in a Primary Culture of Sea Cucumber Intestinal Cells

Primary cultured cells are used in a variety of scientific disciplines as exceptionally important tools for the functional evaluation of biological substances or characterization of specific biological activities. However, due to the lack of universally applicable cell culture media and protocols, well described cell culture methods for marine organisms are still limited. Meanwhile, the commonly occurring microbial contamination and polytropic properties of marine invertebrate cells further impede the establishment of an effective cell culture strategy for marine invertebrates. Here, we describe an easy-to-handle method for culturing intestinal cells from sea cucumber Apostichopus japonicus; additionally, we provide an example of in vitro apoptosis induction and detection in primary cultured intestinal cells. Moreover, this experiment provides details about the appropriate culture medium and cell collection method. The described protocol is compatible with a variety of widely available tissue samples from marine organisms including Echinodermata, Mollusca, and Crustacea, and it can provide sufficient cells for multiple in vitro experimental applications. This technique would enable researchers to efficiently manipulate primary cell cultures from marine invertebrates and to facilitate the functional evaluation of targeted biological materials on cells.

This protocol provides an easy-to-handle method to culture the intestinal cells from sea cucumber Apostichopus japonicus and is compatible with a variety of widely available tissue samples from marine organisms including Echinodermata, Mollusca, and Crustacea.

Primary cultured cells are used in a variety of scientific disciplines as exceptionally important tools for the functional evaluation of biological ...