Name: measuring the effect of chemicals on the growth and reproduction of caenorhabditis elegans
Uploaded: 2017-10-05T15:00:00
Description: Watch this Scientific Journal Video about Measuring the Effect of Chemicals on the Growth and Reproduction of Caenorhabditis elegans at JoVE.com

This study was supported by the Korea Institute of Science and Technology intramural research grant (2E27513) and the High Value-added Food Technology Development Program (IPET) funded by the Ministry of Agriculture, Food and Rural Affairs (315067-03).

NOTE: The entire experiment must be performed in a clean isolated laboratory maintained at 20 &#176;C with low dust and with minimization of contamination during worm and bacterial handling. For this purpose, experiments must be performed under the flame of an alcohol lamp or using a clean bench.
1. Maintenance of C. elegans and Egg Preparation for the Chemical Test
<ol>
	<li>Maintain C. elegans N2 (var. Bristol) on an NGM agar plate fed with live E. coli OP50 at 2...

<ol>
	<li>Blomme, E. A., Will, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toxicology+strategies+for+drug+discovery:+present+and+future.">Toxicology strategies for drug discovery: present and future.</a> Chem. Res. Toxicol. 29 (4), 473-504 (2016).</li><li>Lilienblum, W., 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=Alternative+methods+to+safety+studies+in+experimental+animals:+role+in+the+risk+assessment+of+chemicals+under+the+new+European+Chemicals+Legislation+(REACH).">Alternative methods to safety studies in experimental animals: role in the risk assessment of chemicals under the new European Chemicals Legislation (REACH).</a> Arch. 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Toxicol. 37 (1), 50-59 (2017).</li><li>Porta-de-la-Riva, M., Fontrodona, L., Villanueva, A., Ceron, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Basic+Caenorhabditis+elegans+methods:+synchronization+and+observation.">Basic Caenorhabditis elegans methods: synchronization and observation.</a> J. Vis. Exp. (64), e4019 (2012).</li><li>Lee, S. Y., Kim, J. Y., Jung, Y. J., Kang, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toxicological+evaluation+of+the+topoisomerase+inhibitor,+etoposide,+in+the+model+animal+Caenorhabditis+elegans+and+3T3-L1+normal+murine+cells.">Toxicological evaluation of the topoisomerase inhibitor, etoposide, in the model animal Caenorhabditis elegans and 3T3-L1 normal murine cells.</a> Environ. 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Pharmacol. 45, 356-361 (2016).</li><li>Guo, X., 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=Perfluorooctane+sulfonate+exposure+causes+gonadal+developmental+toxicity+in+Caenorhabditis+elegans+through+ROS-induced+DNA+damage.">Perfluorooctane sulfonate exposure causes gonadal developmental toxicity in Caenorhabditis elegans through ROS-induced DNA damage.</a> Chemosphere. 155, 115-126 (2016).</li><li>Allard, P., Kleinstreuer, N. C., Knudsen, T. B., Colaiacovo, M. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+C.+elegans+screening+platform+for+the+rapid+assessment+of+chemical+disruption+of+germline+function.">A C. elegans screening platform for the rapid assessment of chemical disruption of germline function.</a> Environ. Health Perspect. 121 (6), 717-724 (2013).</li><li>Singh, S., Sharma, B., Kanwar, S. S., Kumar, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lead+phytochemicals+for+anticancer+drug+development.">Lead phytochemicals for anticancer drug development.</a> Front. Plant Sci. 7, 1667 (2016).</li><li>Kang, 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=A+novel+topoisomerase+inhibitor,+daurinol,+suppresses+growth+of+HCT116+cells+with+low+hematological+toxicity+compared+to+etoposide.">A novel topoisomerase inhibitor, daurinol, suppresses growth of HCT116 cells with low hematological toxicity compared to etoposide.</a> Neoplasia. 13 (11), 1043-1057 (2011).</li><li>Chaudhuri, J., Parihar, M., Pires-daSilva, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+introduction+to+worm+lab:+from+culturing+worms+to+mutagenesis.">An introduction to worm lab: from culturing worms to mutagenesis.</a> J. Vis. Exp. (47), e2293 (2011).</li><li>Zarse, 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=Impaired+insulin/IGF1+signaling+extends+life+span+by+promoting+mitochondrial+L-proline+catabolism+to+induce+a+transient+ROS+signal.">Impaired insulin/IGF1 signaling extends life span by promoting mitochondrial L-proline catabolism to induce a transient ROS signal.</a> Cell Metab. 15 (4), 451-465 (2012).</li><li>Sutphin, G. L., Kaeberlein, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measuring+Caenorhabditis+elegans+life+span+on+solid+media.">Measuring Caenorhabditis elegans life span on solid media.</a> J. Vis. Exp. (27), e1152 (2009).</li><li>Weimer, S., 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=D-Glucosamine+supplementation+extends+life+span+of+nematodes+and+of+ageing+mice.">D-Glucosamine supplementation extends life span of nematodes and of ageing mice.</a> Nat. Commun. 5, 3563 (2014).</li><li>Schmeisser, S., 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=Neuronal+ROS+signaling+rather+than+AMPK/sirtuin-mediated+energy+sensing+links+dietary+restriction+to+lifespan+extension.">Neuronal ROS signaling rather than AMPK/sirtuin-mediated energy sensing links dietary restriction to lifespan extension.</a> Mol. Metab. 2 (2), 92-102 (2013).</li><li>Parodi, D. A., Damoiseaux, R., Allard, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comprehensive+assessment+of+germline+chemical+toxicity+using+the+nematode+Caenorhabditis+elegans.">Comprehensive assessment of germline chemical toxicity using the nematode Caenorhabditis elegans.</a> J. Vis. Exp. (96), e52445 (2015).</li><li>Hahm, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=C.+elegans+maximum+velocity+correlates+with+healthspan+and+is+maintained+in+worms+with+an+insulin+receptor+mutation.">C. elegans maximum velocity correlates with healthspan and is maintained in worms with an insulin receptor mutation.</a> Nat. Commun. 6, 8919 (2015).</li><li>Nussbaum-Krammer, C. I., Neto, M. F., Brielmann, R. M., Pedersen, J. S., Morimoto, R. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigating+the+spreading+and+toxicity+of+prion-like+proteins+using+the+metazoan+model+organism+C.+elegans.">Investigating the spreading and toxicity of prion-like proteins using the metazoan model organism C. elegans.</a> J. Vis. Exp. (95), e52321 (2015).</li><li>Schmidt, B. Z., 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=In+vitro+acute+and+developmental+neurotoxicity+screening:+an+overview+of+cellular+platforms+and+high-throughput+technical+possibilities.">In vitro acute and developmental neurotoxicity screening: an overview of cellular platforms and high-throughput technical possibilities.</a> Arch. Toxicol. 91 (1), 1-33 (2017).</li><li>Fey, S. J., Wrzesinski, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+drug+toxicity+using+3D+spheroids+constructed+from+an+immortal+human+hepatocyte+cell+line.">Determination of drug toxicity using 3D spheroids constructed from an immortal human hepatocyte cell line.</a> Toxicol. Sci. 127 (2), 403-411 (2012).</li></ol>

In this article, we describe the toxicity evaluation of chemicals in C. elegans, a soil nematode, using etoposide as a toxicant example. For this purpose, we used two experimental conditions. In the first set, C. elegans were grown on etoposide containing plates from eggs to the young adult stage, and then the worms were allowed to lay eggs on normal NGM plates without chemicals. In the second experimental set, C. elegans were continuously treated with etoposide throughout the whole experimenta...

Toxicological evaluation is essential for the development of pharmaceuticals, nutraceuticals, and cosmeceuticals, as well as the risk assessment of various environmental toxins. The rodent model is one of the most popular in vivo experimental systems for this toxicology study; alternatively, non-mammalian organisms such as C. elegans are also widely used. Non-mammalian toxicological evaluation models are beneficial because of not only animal ethical issues but also their convenience and usefulness considering cost-effectiveness, maintainability, speed, and reproducibility1,2,3,4.
C. elegans, a soil round worm, has been exploited as a model animal in various basic and applied biology and chemistry research. It is a 1 mm long, transparent nematode, which is simply maintained in solid or liquid Nematode Growth Media (NGM) fed with the bacterial strain Escherichia coli OP50. C. elegans has a short life cycle, and wild-type N2 C. elegans lays approximately 300 eggs. Therefore, it is easily propagated to be used as experimental materials3,4,5. C. elegans has also been widely used in the toxicological studies of many drugs and environmental pollutants6,7,8,9.
Because many anticancer drugs target rapidly dividing cancer cells, they can also damage rapidly dividing normal cells such as bone marrow, intestinal epithelium, and hair follicle cells. For example, topoisomerase inhibitory anticancer drugs target the DNA replication process of cancer cells; therefore, they also inhibit rapidly dividing normal cells. Every living organism has topoisomerases, and these topoisomerase inhibitors most likely impact environmental ecosystems6,10,11. Thus, a drug toxicological evaluation platform using a model animal is valuable for both the development of pharmaceuticals and environmental risk assessment.
In this article, we describe the detailed protocols to test the toxicity of etoposide, which is a clinical anticancer agent that targets topoisomerase II, as a model toxic chemical in C. elegans. For this purpose, we will describe the measurement method of body size and the total number of eggs laid in C. elegans treated with etoposide.

<table>
	<tbody>
		<tr>
			<td>Agar</td>
			<td>Affymetrix, USA</td>
			<td>10906</td>
			<td></td>
		</tr>
		<tr>
			<td>Caenorhabditis elegans N2</td>
			<td>Caenorhabditis Genetics Center (CGC)</td>
			<td></td>
			<td>Wild type</td>
		</tr>
		<tr>
			<td>Cholesterol</td>
			<td>Sigma, USA</td>
			<td>C3045</td>
			<td></td>
		</tr>
		<tr>
			<td>Dimethyl sulfoxide</td>
			<td>Sigma, USA</td>
			<td>D2650</td>
			<td></td>
		</tr>
		<tr>
			<td>Escherichia coli OP50</td>
			<td>Caenorhabditis Genetics Center (CGC)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Etoposide</td>
			<td>Sigma, USA</td>
			<td>E1383</td>
			<td></td>
		</tr>
		<tr>
			<td>Image J software (ver 1.4)</td>
			<td>Natinoal Institute of Health, USA</td>
			<td></td>
			<td>https://imagej.nih.gov/ij/</td>
		</tr>
		<tr>
			<td>Microscope camera</td>
			<td>Jenopitk, Progress Gryphax, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Peptone</td>
			<td>Merck, USA</td>
			<td>107213</td>
			<td></td>
		</tr>
		<tr>
			<td>35 &#215; 10 mm Petri dish</td>
			<td>SPL Life Sciences, South Korea</td>
			<td>10035</td>
			<td></td>
		</tr>
		<tr>
			<td>90 &#215; 15 mm Petri dish</td>
			<td>SPL Life Sciences, South Korea</td>
			<td>10090</td>
			<td></td>
		</tr>
		<tr>
			<td>Stereo microscope</td>
			<td>Nikon, Japan</td>
			<td>SMZ800N</td>
			<td></td>
		</tr>
		<tr>
			<td>Yeast extract</td>
			<td>Becton Dickinson, USA</td>
			<td>212750</td>
			<td></td>
		</tr>
	</tbody>
</table>

measuring the effect of chemicals on the growth and reproduction of caenorhabditis elegans

Toxicological evaluation is crucial for understanding the effects of chemicals on living organisms in basic and applied biological science fields. A non-mammalian soil round worm, Caenorhabditis elegans, is a valuable model organism for toxicology studies due to its convenience and lack of animal ethics issues compared with mammalian animal systems. In this protocol, a detailed procedure of toxicological evaluation of chemicals in C. elegans is described. A clinical anticancer drug, etoposide, which targets human topoisomerase II and inhibits DNA replication of human cancer cells, was selected as a model testing chemical. Age-synchronized C. elegans eggs were exposed to either dimethyl sulfoxide (DMSO) or etoposide, and then the growth of C. elegans was monitored every day for 4 days by the stereo microscope observation. The total number of eggs laid from C. elegans treated with DMSO or etoposide was also counted by using the stereo microscope. Etoposide treatment significantly affected the growth and reproduction of C. elegans. By comparison of the total number of eggs laid from worms with different treatment periods of chemicals, it can be decided that the reproductive toxicity of chemicals on C. elegans reproduction is reversible or irreversible. These protocols may be helpful for both the development of various drugs and risk assessment of environmental toxicants.

The treatment of etoposide (24-96 h) significantly retarded the growth of C. elegans. After 96 h of incubation, etoposide-treated worms grew to 0.86 mm in body length, while the vehicle-treated worms grew to 1.04 mm (Figure 1). Growth retardation was also apparently observed under stereo microscope observation (Figure 2). We started to see eggs from the vehicle-treated worms at 72 h of incubation. On the other hand, eggs...

Watch this Scientific Journal Video about Measuring the Effect of Chemicals on the Growth and Reproduction of Caenorhabditis elegans at JoVE.com

Measuring the Effect of Chemicals on the Growth and Reproduction of Caenorhabditis elegans

A basic protocol to evaluate the toxicity of chemicals in a model animal, Caenorhabditis elegans, is described. The method is convenient and useful for the development of pharmaceuticals as well as for the risk assessment of various environmental pollutants.

Measuring the Effect of Chemicals on the Growth and Reproduction of Caenorhabditis elegans

Toxicological evaluation is crucial for understanding the effects of chemicals on living organisms in basic and applied biological science fields. A ...

The overall goal of this procedure is to measure the effect of chemicals, such as the topoisomerase inhibitor etoposide, on the growth and reproduction of the model animal Caenorhabditis elegans. This method can help answer key questions in the toxicology field, such as toxicological evaluation for the development of drugs and risk assessment of environmental toxicants. The main advantage of this technique is that the toxicity of various chemicals can be checked in non-mammalian systems, so this technique is convenient and cost-effective.Demonstrating the procedure will be So Young Lee, a graduate student from my laboratory. To begin, prepare two clean, 200-milliliter glass bottles by adding 0.6 grams of sodium chloride, 0.5 grams of peptone, 3.4 grams of agar, 195 milliliters of distilled water, and a magnetic stirrer to one bottle. Then add a magnetic stirrer to the other empty bottle.Autoclave the bottles for 15 minutes at 121 degrees Celsius, and then cool down the bottles in a water bath for 30 minutes at 55 degrees Celsius. Next, to the filled bottle, add 0.2 milliliters of one molar calcium chloride, 0.2 milliliters of five milligrams per milliliter cholesterol, 0.2 milliliters of one molar magnesium sulfate, and five milliliters of one molar potassium phosphate. Then mix the solution by magnetic stirring on a hot plate at 55 degrees Celsius.Pour half of the mixed NGM medium into the empty 200-milliliter bottle. Then add one milliliter of DMSO to one bottle, and use magnetic stirring to mix it again. Store the other bottle in a water bath at 55 degrees Celsius.Then aliquot three milliliters of the DMSO-containing medium to 35-by-10-millimeter Petri dishes. Remove the other bottle from the water bath, and use magnetic stirring to mix it. Then add one milliliter of 75-millimolar etoposide.And after mixing again, repeat the aliquoting procedure. Cool down the chemical-containing NGM plates by leaving them at room temperature for approximately three hours, and store them at four degrees Celsius until use. For the chemical test, spread 100 microliters of heat-inactivated E.coli OP50 on each NGM plate.Allow the plates to dry overnight in a C.elegans incubator at 20 degrees Celsius. Transfer the age-synchronized C.elegans eggs to an NGM plate supplemented with 1%DMSO or 750-micromolar etoposide. Place the C.elegans in an incubator at 20 degrees Celsius for four days.Observe and take microscopic images of C.elegans under stereo microscope every day. Also, take a microscopic image of the microscope stage micrometer for worm size calibration. To measure the body length of C.elegans treated with DMSO or etoposide at each time point, in ImageJ, open the microscope stage micrometer image.Then using the Straight Line tool, drag a line of 1, 000 micrometers on the image. Click Analyze and then Set Scale, and input 1, 000 and micrometers into the Known Distance box and Unit of Length box, respectively. Then check Global and click OK.Open the worm images using File and then Open.Then, using the Freehand Line tool, draw a line along the feature of each worm. Obtain the body length data by clicking Analyze and then Measure. Repeat these steps for 50 worms.Incubate the age-synchronized eggs on the NGM plate containing DMSO or etoposide at 20 degrees Celsius for 64 hours until the young adult stage. Transfer five adult worms to new NGM plates without chemicals or new NGM plates containing the same chemical pretreatment, and incubate them for 24 hours. Transfer the adults to new NGM plates, as just demonstrated, and count the number of eggs every day.In addition, count the worms that crawled off, died, or were internally hatched. Carry out calculations according to the text protocol. As shown here, the treatment of etoposide at 24 to 96 hours significantly retarded the growth of C.elegans.After 96 hours of incubation, etoposide-treated worms grew to 0.86 millimeters in body length while the vehicle-treated worms grew to 1.04 millimeters. Growth retardation was also observed under stereo microscope observation, as seen in these images of etoposide-treated worms, as compared to control-treated worms. After 72 hours of incubation, eggs from the vehicle-treated worms were observed.In contrast, eggs were observed after 96 hours of etoposide treatment, raising the possibility that etoposide treatment delayed the first birth time of C.Elegans. As depicted in these graphs, a decrease in total egg number by etoposide treatment was observed when the young adult worms were cultured, either in the presence or absence of continuous etoposide treatment. Once mastered, this technique can be done in one week if it is performed properly.After watching this video, you should have a good understanding of how to evaluate chemical toxicity in C.elegans, a model nematode.

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Measuring the Strength of Mice

Kondziela7 devised the inverted screen test and published it in 1964. It is a test of muscle strength using all four limbs. Most normal mice easily score maximum on this task; it is a quick but insensitive gross screen, and the weights test described in this article will provide a finer measure of muscular strength.
There are also several strain gauge-based pieces of apparatus available commercially that will provide more graded data than the inverted screen test, but their cost may put them beyond the reach of many laboratories which do not specialize in strength testing. Hence in 2000 a cheap and simple apparatus was devised by the author. It consists of a series of chain links of increasing length, attached to a "fur collector" a ball of fine wire mesh sold for preventing limescale build up in hard water areas. An accidental observation revealed that mice could grip these very tightly, so they proved ideal as a grip point for a weight-lifting apparatus. A common fault with commercial strength meters is that the bar or other grip feature is not thin enough for mice to exert a maximum grip. As a general rule, the thinner the wire or bar, the better a mouse can grip with its small claws.
This is a pure test of strength, although as for any test motivational factors could potentially play a role. The use of scale collectors, however, seems to minimize motivational problems as the motivation appears to be very high for most normal young adult mice.

Deficits in muscular strength occur in many clinical conditions such as motor neuron disease. The inverted screen and weight lifting tests described here measure strength in mice almost exclusively, with minimal influence of factors such as coordination.

Kondziela7 devised the inverted screen test and published it in 1964. It is a test of muscle strength using all four limbs. Most normal mice easily score ...

Immunohistochemical Staining of B7-H1 (PD-L1) on Paraffin-embedded Slides of Pancreatic Adenocarcinoma Tissue

B7-H1/PD-L1, a member of the B7 family of immune-regulatory cell-surface proteins, plays an important role in the negative regulation of cell-mediated immune responses through its interaction with its receptor, programmed death-1 (PD-1) 1,2. Overexpression of B7-H1 by tumor cells has been noted in a number of human cancers, including melanoma, glioblastoma, and carcinomas of the lung, breast, colon, ovary, and renal cells, and has been shown to impair anti-tumor T-cell immunity3-8.
Recently, B7-H1 expression by pancreatic adenocarcinoma tissues has been identified as a potential prognostic marker9,10. Additionally, blockade of B7-H1 in a mouse model of pancreatic cancer has been shown to produce an anti-tumor response11. These data suggest the importance of B7-H1 as a potential therapeutic target. Anti-B7-H1 blockade antibodies are therefore being tested in clinical trials for multiple human solid tumors including melanoma and cancers of lung, colon, kidney, stomach and pancreas12.
In order to eventually be able to identify the patients who will benefit from B7-H1 targeting therapies, it is critical to investigate the correlation between expression and localization of B7-H1 and patient response to treatment with B7-H1 blockade antibodies. Examining the expression of B7-H1 in human pancreatic adenocarcinoma tissues through immunohistochemistry will give a better understanding of how this co-inhibitory signaling molecule contributes to the suppression of antitumor immunity in the tumor's microenvironment. The anti-B7-H1 monoclonal antibody (clone 5H1) developed by Chen and coworkers has been shown to produce reliable staining results in cryosections of multiple types of human neoplastic tissues4,8, but staining on paraffin-embedded slides had been a challenge until recently13-18. We have developed the B7-H1 staining protocol for paraffin-embedded slides of pancreatic adenocarcinoma tissues. The B7-H1 staining protocol described here produces consistent membranous and cytoplasmic staining of B7-H1 with little background.

Immunohistochemical Staining of B7-H1 PD-L1 on Paraffin-embedded Slides of Pancreatic Adenocarcinoma Tissue

B7-H1 (PD-L1) and its binding to PD-1 provide a major tumor-induced immunosuppressive signal in the tumor&#x2019;s microenvironment. An immunohistochemical staining technique to characterize the expression and localization of B7-H1 in pancreatic adenocarcinoma is described here.

B7-H1/PD-L1, a member  of the B7 family of immune-regulatory cell-surface proteins, plays an important  role in the negative regulation of cell-mediated ...

Measuring Frailty in HIV-infected Individuals. Identification of Frail Patients is the First Step to Amelioration and Reversal of Frailty

A simple, validated protocol consisting of a battery of tests is available to identify elderly patients with frailty syndrome. This syndrome of decreased reserve and resistance to stressors increases in incidence with increasing age. In the elderly, frailty may pursue a step-wise loss of function from non-frail to pre-frail to frail. We studied frailty in HIV-infected patients and found that ~20% are frail using the Fried phenotype using stringent criteria developed for the elderly1,2. In HIV infection the syndrome occurs at a younger age.
HIV patients were checked for 1) unintentional weight loss; 2) slowness as determined by walking speed; 3) weakness as measured by a grip dynamometer; 4) exhaustion by responses to a depression scale; and 5) low physical activity was determined by assessing kilocalories expended in a week's time. Pre-frailty was present with any two of five criteria and frailty was present if any three of the five criteria were abnormal.
The tests take approximately 10-15 min to complete and they can be performed by medical assistants during routine clinic visits. Test results are scored by referring to standard tables. Understanding which of the five components contribute to frailty in an individual patient can allow the clinician to address relevant underlying problems, many of which are not evident in routine HIV clinic visits.

Frailty syndrome is commonly seen in the aged and reflects multi-system physiological change. However, with reduced functional reserve and resilience frailty is also known to be common in the HIV infected population. This study outlined an easily administered screening test to identify HIV patients with frailty. When significant components of frailty are identified, clinicians will be able to focus on amelioration of the problem and promote reversion to the pre-frail state.

A simple, validated protocol consisting of a battery of tests is available to identify elderly patients with frailty syndrome. This syndrome of decreased ...

The Influence of Liver Resection on Intrahepatic Tumor Growth

The high incidence of tumor recurrence after resection of metastatic liver lesions remains an unsolved problem. Small tumor cell deposits, which are not detectable by routine clinical imaging, may be stimulated by hepatic regeneration factors after liver resection. It is not entirely clear, however, which factors are crucial for tumor recurrence.
The presented mouse model may be useful to explore the mechanisms that play a role in the development of recurrent malignant lesions after liver resection. The model combines the easy-to-perform and reproducible techniques of defined amounts of liver tissue removal and tumor induction (by injection) in mice. The animals were treated with either a single laparotomy, a 30% liver resection, or a 70% liver resection. All animals subsequently received a tumor cell injection into the remaining liver tissue. After two weeks of observation, the livers and tumors were evaluated for size and weight and examined by immunohistochemistry.
After a 70% liver resection, the tumor volume and weight were significantly increased compared to a laparotomy alone (p &#60;0.05). In addition, immunohistochemistry (Ki67) showed an increased tumor proliferation rate in the resection group (p &#60;0.05).
These findings demonstrate the influence of hepatic regeneration mechanisms on intrahepatic tumor growth. Combined with methods like histological workup or RNA analysis, the described mouse model could serve as foundation for a close examination of different factors involved in tumor growth and metastatic disease recurrence within the liver. A considerable number of variables like the length of postoperative observation, the cell line used for injection or the timing of injection and liver resection offer multiple angles when exploring a specific question in the context of post-hepatectomy metastases. The limitations of this procedure are the authorization to perform the procedure on animals, access to an appropriate animal testing facility and acquisition of certain equipment.

A high incidence of tumor recurrence after resection of liver metastases remains an unsolved problem. The illustrated mouse model may be useful to investigate the reasons for such recurrences. It combines a liver resection model with intrahepatic tumor cell injection for the first time.

The high incidence of tumor recurrence after resection of metastatic liver lesions remains an unsolved problem. Small tumor cell deposits, which are not ...

Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle

Skeletal muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity, which is critically important in health and disease, can be measured in vivo and noninvasively in humans via phosphorus-31 magnetic resonance spectroscopy (31PMRS). However, the approach has not been widely adopted in translational and clinical research, with variations in methodology and limited guidance from the literature. Increased optimization, standardization, and dissemination of methods for in vivo 31PMRS would facilitate the development of targeted therapies to improve OXPHOS capacity and could ultimately favorably impact cardiovascular health. 31PMRS produces a noninvasive, in vivo measure of OXPHOS capacity in human skeletal muscle, as opposed to alternative measures obtained from explanted and potentially altered mitochondria via muscle biopsy. It relies upon only modest additional instrumentation beyond what is already in place on magnetic resonance scanners available for clinical and translational research at most institutions. In this work, we outline a method to measure in vivo skeletal muscle OXPHOS. The technique is demonstrated using a 1.5 Tesla whole-body MR scanner equipped with the suitable hardware and software for 31PMRS, and we explain a simple and robust protocol for in-magnet resistive exercise to rapidly fatigue the quadriceps muscle. Reproducibility and feasibility are demonstrated in volunteers as well as subjects over a wide range of functional capacities.

Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle

This work demonstrates the feasibility of an in vivo phosphorus-31 magnetic resonance spectroscopy (31PMRS) technique to quantify mitochondrial oxidative phosphorylation (OXPHOS) capacity in human skeletal muscle.

Skeletal muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity, which is critically important in health and disease, can be measured in vivo ...

Turbidimetry on Human Washed Platelets: The Effect of the Pannexin1-inhibitor Brilliant Blue FCF on Collagen-induced Aggregation

Turbidimetry is a laboratory technique that is applied to measure the aggregation of platelets suspended in either plasma (platelet-rich plasma, PRP) or in buffer (washed platelets), by the use of one or a combination of agonists. The use of washed platelets separated from their plasma environment and in the absence of anticoagulants allows for studying intrinsic platelet properties. Among the large panel of agonists, arachidonic acid (AA), adenosine di-phosphate (ADP), thrombin and collagen are the most frequently used. The aggregation response is quantified by measuring the relative optical density (OD) over time of platelet suspension under continuous stirring. Platelets in homogeneous suspension limit the passage of light after the addition of an agonist, platelet shape change occurs producing a small transitory increase in OD. Following this initial activation step, platelet clots form gradually, allowing the passage of light through the suspension as a result of decreased OD. The aggregation process is ultimately expressed as a percentage, compared to the OD of platelet-poor plasma or buffer. Rigorous calibration is thus essential at the beginning of each experiment. As a general rule: calibration to 0% is set by measuring the OD of a non-stimulated platelet suspension while measuring the OD of the suspension medium containing no platelets represents a value of 100%. Platelet aggregation is generally visualized as a real-time aggregation curve. Turbidimetry is one of the most commonly used laboratory techniques for the investigation of platelet function and is considered as the historical gold standard and used for the development of new pharmaceutical agents aimed at inhibiting platelet aggregation. Here, we describe detailed protocols for 1) preparation of human washed platelets and 2) turbidimetric analysis of collagen-induced aggregation of human washed platelets pretreated with the food dye Brilliant Blue FCF that was recently identified as an inhibitor of Pannexin1 (Panx1) channels.

We describe a straightforward method for the isolation of washed platelets from human blood followed by agonist-induced platelet aggregation measurements by turbidimetry. As an example we apply this method for studying the aggregation response of human platelets to collagen after a pre-incubation with the Pannexin1 channel inhibitor Brilliant Blue FCF.

Turbidimetry is a laboratory technique that is applied to measure the aggregation of platelets suspended in either plasma (platelet-rich plasma, PRP) or ...

A Primary Human Trophoblast Model to Study the Effect of Inflammation Associated with Maternal Obesity on Regulation of Autophagy in the Placenta

Maternal obesity is associated with an increased risk of adverse perinatal outcomes that are likely mediated by compromised placental function that can be attributed to, in part, the dysregulation of autophagy. Aberrant changes in the expression of autophagy regulators in the placentas from obese pregnancies may be regulated by inflammatory processes associated with both obesity and pregnancy. Described here is a protocol for sampling of villous tissue and isolation of villous cytotrophoblasts from the term human placenta for primary cell culture. This is followed by a method for simulating the inflammatory milieu in the obese intrauterine environment by treating primary trophoblasts from lean pregnancies with tumor necrosis factor alpha (TNF&#945;), a proinflammatory cytokine that is elevated in obesity and in pregnancy. Through the implementation of the protocol described here, it is found that exposure to exogenous TNF&#945; regulates the expression of Rubicon, a negative regulator of autophagy, in trophoblasts from lean pregnancies with female fetuses. While a variety of biological factors in the obese intrauterine environment maintain the potential to modulate critical pathways in trophoblasts, this ex vivo system is especially useful for determining if expression patterns observed in vivo in human placentas with maternal obesity are a direct result of TNF&#945; signaling. Ultimately, this approach affords the opportunity to parse out the regulatory and molecular implications of inflammation associated with maternal obesity on autophagy and other critical cellular pathways in trophoblasts that have the potential to impact placental function.

Presented here is a protocol for sampling of human placental villous tissue followed by isolation of cytotrophoblasts for primary cell culture. Treatment of trophoblasts with TNF&#945; recapitulates inflammation in the obese intrauterine environment and facilitates the discovery of molecular targets regulated by inflammation in placentas with maternal obesity.

Maternal obesity is associated with an increased risk of adverse perinatal outcomes that are likely mediated by compromised placental function that can be ...

Measuring the Effects of Bacteria and Chemicals on the Intestinal Permeability of Caenorhabditis elegans

In living organisms, intestinal hyperpermeability is a serious symptom that leads to many inflammatory bowel diseases (IBDs). Caenorhabditis elegans is a nonmammalian animal model that is widely used as an assay system due to its short lifespan, transparency, cost-effectiveness, and lack of animal ethics issues. In this study, a method was developed to investigate the effects of different bacteria and 3,3'-diindolylmethane (DIM) on the intestinal permeability of C. elegans with a high-throughput image analysis system. The worms were infected with different gut bacteria or cotreated with DIM for 48 h and fed with fluorescein isothiocyanate (FITC)-dextran overnight. Then, the intestinal permeability was examined by comparing the fluorescence images and the fluorescence intensity inside the worm bodies. This method may also have the potential to identify probiotic and pathogenic intestinal bacteria that affect intestinal permeability in the animal model and is effective for examining the effects of harmful or health-promoting chemicals on intestinal permeability and intestinal health. However, this protocol also has some considerable limitations at the genetic level, especially for determining which genes are altered to control illness, because this method is mostly used for phenotypic determination. In addition, this method is limited to determining exactly which pathogenic substrates cause inflammation or increase the permeability of the worms' intestines during infection. Therefore, further in-depth studies, including investigation of the molecular genetic mechanism using mutant bacteria and nematodes as well as chemical component analysis of bacteria, are required to fully evaluate the function of bacteria and chemicals in determining intestinal permeability.

Measuring the Effects of Bacteria and Chemicals on the Intestinal Permeability of Caenorhabditis elegans

This protocol describes how to measure intestinal permeability of Caenorhabditis elegans. This method is helpful for basic biological research on intestinal health related to the interaction between intestinal bacteria and their host and for screening to identify probiotic and chemical agents to cure leaky gut syndrome and inflammatory bowel diseases.

In living organisms, intestinal hyperpermeability is a serious symptom that leads to many inflammatory bowel diseases (IBDs). Caenorhabditis elegans is a ...

Effect of Artificial Tear Formulations on the Metabolic Activity of Human Corneal Epithelial Cells after Exposure to Desiccation

Artificial lipid-containing tear formulations are developed to reduce tear evaporation by the restoration of a deficient tear lipid layer. Artificial tear formulations that prevent cell desiccation will result in ocular surface protection and the maintenance of cell metabolic activity. During dehydration, cells undergo the process of loss of metabolic activity and subsequently cell death. This work describes a method for assessing the efficacy of artificial tear formulations. The metabolic dye (i.e., alamarBlue) changes from a low fluorescent molecule resazurin to a fluorescent molecule resorufin in viable cells. The biological performance of an artificial tear formulation is measured as the ability of the formulation to (a) maintain cell viability and (b) provide cell protection from desiccation. Growth media and saline are used as controls for the cell viability/desiccation tests. Cells are incubated with test solutions for 30 min and then desiccated for 0 or 5 min at 37 &#176;C and 45% relative humidity. Cell metabolic activity after initial exposure and after cell desiccation is then determined. The results show the comparative effects of eye drop formulations on cell metabolic activity and desiccation protection. This method can be used to test dry eye formulations that are designed to treat individuals with evaporative dry eye.

The purpose of this protocol is to evaluate if different artificial tear formulations can protect human corneal epithelial cells from desiccation using an in vitro model. After exposure to artificial tear formulations and desiccation, human corneal epithelial cells are assessed for metabolic activity.

Artificial lipid-containing tear formulations are developed to reduce tear evaporation by the restoration of a deficient tear lipid layer. Artificial tear ...

Design and Development of a Model to Study the Effect of Supplemental Oxygen on the Cystic Fibrosis Airway Microbiome

Airway microbial communities are thought to play an important role in the progression of cystic fibrosis (CF) and other chronic pulmonary diseases. Microbes have traditionally been classified based on their ability to use or tolerate oxygen. Supplemental oxygen is a common medical therapy administered to people with cystic fibrosis (pwCF); however, existing studies on oxygen and the airway microbiome have focused on how hypoxia (low oxygen) rather than hyperoxia (high oxygen) affects the predominantly aerobic and facultative anaerobic lung microbial communities. To address this critical knowledge gap, this protocol was developed using an artificial sputum medium that mimics the composition of sputum from pwCF. The use of filter sterilization, which yields a transparent medium, allows optical methods to follow the growth of single-celled microbes in suspension cultures. To create hyperoxic conditions, this model system takes advantage of established anaerobic culturing techniques to study hyperoxic conditions; instead of removing oxygen, oxygen is added to cultures by daily sparging of serum bottles with a mixture of compressed oxygen and air. Sputum from 50 pwCF underwent daily sparging for a 72-h period to verify the ability of this model to maintain differential oxygen conditions. Shotgun metagenomic sequencing was performed on cultured and uncultured sputum samples from 11 pwCF to verify the ability of this medium to support the growth of commensal and pathogenic microbes commonly found in cystic fibrosis sputum. Growth curves were obtained from 112 isolates obtained from pwCF to verify the ability of this artificial sputum medium to support the growth of common cystic fibrosis pathogens. We find that this model can culture a wide variety of pathogens and commensals in CF sputum, recovers a community highly similar to uncultured sputum under normoxic conditions, and creates different culture phenotypes under varying oxygen conditions. This new approach might lead to a better understanding of unanticipated effects induced by the use of oxygen in pwCF on airway microbial communities and common respiratory pathogens.

The goal of this protocol is to develop a model system for the effect of hyperoxia on cystic fibrosis airway microbial communities. Artificial sputum medium emulates the composition of sputum, and hyperoxic culture conditions model the effects of supplemental oxygen on lung microbial communities.

Airway microbial communities are thought to play an important role in the progression of cystic fibrosis (CF) and other chronic pulmonary diseases. ...