This work was funded by a National Institutes of Health R01 (DC009453 support to CWB).

NOTA: Prima di fornire campioni di saliva tutti i soggetti hanno dato il consenso informato conforme alle linee guida per il trattamento di soggetti umani all&#39;ospedale dei bambini a livello nazionale. 1 Saliva Raccolta e conservazione <ol><li> Prima della raccolta della saliva, assicurarsi che la bocca del soggetto è libero di cibo o altre sostanze estranee avendo il soggetto sciacquare la bocca con acqua ed evitando di mangiare o bere per 30 minuti prima di raccogliere il campione. </li><li> Aprire una provetta da centrifuga da 15 ml con 2,5 ml di tampone di DNA stabilizzazione 2 avendo cura di evitare di toccare l&#39;interno del tappo o il tubo, e hanno il soggetto sputare 2,5 ml di saliva nella soluzione tampone. Nota: Raccolta di oltre 2,5 ml di saliva può portare al degrado del campione da un rapporto di insufficiente di campione di tampone di stabilizzazione del DNA. Raccolta troppo poco di saliva riduce i rendimenti attesi dal protocollo. Per valutare i volumi di raccolta, utilizzare i gradienti numerati sul lato di tegli tubo. </li><li> Rimettere il tappo e miscelare per inversione fino a quando la miscela è omogeneizzato. Agitazione vigorosa non è necessario. Conservare i campioni a temperatura ambiente per la conservazione a breve termine o 4 ° C per la conservazione a lungo termine (&gt; 3 mesi). </li></ol> 2. Preparazioni iniziali e lisi cellulare <ol><li> Prima di iniziare l&#39;estrazione, riscaldare a bagnomaria a 37 ° C, e preparare un secchio di ghiaccio. Saranno necessari tre provette da 15 ml per centrifuga coniche per ogni campione estratto. I tre tubi saranno utilizzati per contenere il cellulare e proteine ​​pellet, la finale estratto gDNA, e le isopropanolo ed etanolo surnatanti. </li><li> Recupera campioni di stoccaggio, e campioni di invertire tempi diversi poi vortice a media velocità per 15 secondi. </li><li> Dispensare 2.5 ml di campione in un ambiente pulito 15 ml tubo da centrifuga, e aggiungere 5 ml di Cell Lysis Solution. Mescolare il campione 50 volte per inversione, e incubare a temperatura ambiente per 30 min. </li></ol> 3. RNA rimozione <ol><li> Aggiungere 40 ml di RNasi A Solution a 100 mg / ml, e incubare a 37 ° C per 15 min. </li><li> Togliere il campione dal bagno di 37 ° C e acqua fredda su ghiaccio per 3 min. <ol><li> Dopo l&#39;incubazione RNasi A, aumentare la temperatura del bagno d&#39;acqua a 65 ° C per la fase di reidratazione DNA del protocollo. </li></ol></li></ol> 4. Proteine ​​e lipidi di rimozione <ol><li> Aggiungere 50 ml di soluzione di proteinasi K a 20 mg / ml, mescolare più volte per inversione, e incubare a temperatura ambiente per un minimo di 30 min. Nota: Questo è un possibile punto di pausa per il protocollo. Dopo l&#39;aggiunta della soluzione di proteinasi K, il campione può essere conservato a 4 ° C fino al momento dell&#39;estrazione può essere completata. Conservare a 4 ° C per un massimo di 24 ore non è stato dimostrato di avere un effetto significativo sui rendimenti di estrazione o la qualità del DNA. Stoccaggio a lungo termine in questa fase non è stata valutata. </li><li> Aggiungere 1,7 ml di proteina Precipitazione Solution, mescolare vigorosamente nel vortex per 20 secondi ad alta velocità, e posto in ghiaccio per 10 min. </li&gt; <li> Una volta che i campioni sono raffreddati in ghiaccio per 10 minuti, centrifugare per 10 minuti a 3000 xg e 4 ° C. Le proteine ​​precipitate devono formare un pellet stretto per continuare. Se il pellet non è stretto o la soluzione è ancora torbida, i campioni possono essere raffreddati in ghiaccio per 5 minuti di più e centrifugazione ripetuti. I campioni devono essere tenuti in ghiaccio per garantire un pellet stretto. </li></ol> 5. isolamento e la purificazione di gDNA <ol><li> In un ambiente pulito 15 ml tubo da centrifuga, pipetta 5 ml di isopropanolo e 8 ml di puro Soluzione glicogeno a 20 mg / ml. </li><li> Versare il surnatante contenente il gDNA dal punto 4.3 nella provetta contenente la soluzione di isopropanolo e glicogeno, lasciando dietro di sé la proteina pellet precipitato. Una volta aggiunto il surnatante, mescolare delicatamente il campione di 50 volte per inversione e centrifugare per 30 minuti a 3000 xg e 4 ° C. </li><li> Versare lentamente il surnatante in una provetta pulita 15 ml. Dopo la rimozione del surnatante, aggiungere 1 ml di etanolo al 70% perlavare il pellet lentamente a dondolo e spostando delicatamente la etanolo sopra il pellet precipitato più volte. Conservare l&#39;etanolo nel tubo. </li><li> Dopo il lavaggio iniziale, centrifugare il campione per 1 min a 2.000 xg e 20 ° C. Questa fase di centrifugazione può essere fatta sia a 4 ° C o 20 ° C. Nessun effetto significativo della temperatura è stato dimostrato per questo passo. </li><li> Dopo il lavaggio iniziale e la centrifugazione del pellet, versare lentamente il lavaggio etanolo dal tubo ed eliminare, quindi eseguire un secondo lavaggio ripetendo i punti 5.3 e 5.4. </li><li> Dopo la rimozione del supernatante dal secondo lavaggio, permettere il pellet asciugare all&#39;aria per 15 min. <ol><li> Se il campione non si è completamente asciugato, aria secca per altri 15 min. </li></ol></li></ol> 6. reidratazione di gDNA <ol><li> Una volta che il campione si è asciugato, aggiungere 300 ml di Tris-EDTA per reidratare il pellet gDNA secca. </li><li> Vortex il campione per 5 secondi a velocità media e posto in un65 ° C in bagno di acqua calda per 1 ora. </li><li> Rimuovere i campioni dal bagnomaria e incubare O / N a RT. NOTA: Tutti i prodotti ei reagenti utilizzati sono elencati nella tabella dei materiali, così come Tabella 4. </li></ol>

<ol>
	<li>Quinque, D., Kittler, R., Kayser, M., Stoneking, M., Nasidze, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+saliva+as+a+source+of+human+DNA+for+population+and+association+studies.">Evaluation of saliva as a source of human DNA for population and association studies.</a> Analytical Biochemistry. 353, 272-277 (2006).</li><li>Min, J. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+mircosatellite+and+SNP+genotyping+success+rates+established+in+a+large+number+of+genomic+DNA+samples+extracted+from+mouth+swabs+and+genotypes.">High mircosatellite and SNP genotyping success rates established in a large number of genomic DNA samples extracted from mouth swabs and genotypes.</a> Twin Research and Human Genetics. 9, 501-506 (2006).</li><li>Dlugos, D. J., Scattergood, T. M., Ferraro, T. N., Berrettinni, W. H., Buono, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recruitment+rates+and+fear+of+phlebotomy+in+pediatric+patients+in+a+genetic+study+of+epilepsy.">Recruitment rates and fear of phlebotomy in pediatric patients in a genetic study of epilepsy.</a> Epilepsy &amp; Behavior. 6, 444-446 (2005).</li><li>Etter, J. F., Neidhart, E., Bertand, S., Malafosse, A., Bertrand, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Collecting+saliva+by+mail+for+genetic+and+cotinine+analyses+in+participants+recruited+through+the+internet.">Collecting saliva by mail for genetic and cotinine analyses in participants recruited through the internet.</a> European Journal of Epidemiology. 20, 833-838 (2005).</li><li>Hansen, T. V., Simonsen, M. K., Nielsen, F. C., Hundrup, Y. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Collection+of+blood,+saliva,+and+buccal+cell+samples+in+a+pilot+study+on+the+danish+nurse+cohort:+Comparison+of+the+response+rate+and+quality+of+genomic+DNA.">Collection of blood, saliva, and buccal cell samples in a pilot study on the danish nurse cohort: Comparison of the response rate and quality of genomic DNA.</a> Cancer Epidemiol Biomarkers Prev. 16, 2072-2076 (2007).</li><li>Van Schie, R. C. A. A., Wilson, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Saliva:+A+convenient+source+of+DNA+for+analysis+of+bi-allelic+polymorphisms+of+fc&#947;+receptor+iia+(cd32)+and+fc&#947;+receptor+iiib+(cd16).">Saliva: A convenient source of DNA for analysis of bi-allelic polymorphisms of fc&#947; receptor iia (cd32) and fc&#947; receptor iiib (cd16).</a> Journal of Immunological Methods. 208, 91-101 (1997).</li><li>Dawes, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estimates,+from+salivary+analyses,+of+the+turnover+time+of+oral+mucosal+epithelium+in+humans+and+the+number+of+bacteria+in+an+edentulous+mouth.">Estimates, from salivary analyses, of the turnover time of oral mucosal epithelium in humans and the number of bacteria in an edentulous mouth.</a> Archives of Oral Biology. 48, 329-336 (2003).</li><li>Bahlo, 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=Saliva-derived+DNA+performs+well+in+large-scale,+high-density+single-nucleotide+polymorphism+microarray+studies.">Saliva-derived DNA performs well in large-scale, high-density single-nucleotide polymorphism microarray studies.</a> Cancer Epidemiol Biomarkers Prev. 19, 794-798 (2010).</li><li>Hu, Y., 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=Genotyping+performance+between+saliva+and+blood-derived+genomic+dnas+on+the+dmet+array:+A+comparison.">Genotyping performance between saliva and blood-derived genomic dnas on the dmet array: A comparison.</a> PLoS ONE. 7 (3), e33968 (2012).</li><li>Simmons, T. R., 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=Increasing+genotype-phenotype+model+determinism:+Application+to+bivariate+reading/language+traits+and+epistatic+interactions+in+language-impaired+families.">Increasing genotype-phenotype model determinism: Application to bivariate reading/language traits and epistatic interactions in language-impaired families.</a> Human Heredity. 70, 232-244 (2010).</li><li>Zeugin, J. A., Hartley, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ethanol+precipitation+of+DNA.">Ethanol precipitation of DNA.</a> Focus. 7, 1-2 (1985).</li><li>Li, H., Durbin, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fast+and+accurate+short+read+alignment+with+Burrows-Wheeler+Transform.">Fast and accurate short read alignment with Burrows-Wheeler Transform.</a> Bioinformatics. 25, 1754-1760 (2009).</li><li>McKenna, 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=The+Genome+Analysis+Toolkit:+a+MapReduce+framework+for+analyzing+next-generation+DNA+sequencing+data.">The Genome Analysis Toolkit: a MapReduce framework for analyzing next-generation DNA sequencing data.</a> Genome Res. 20, 1297-1303 (2010).</li><li>DePristo, 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=A+framework+for+variation+discovery+and+genotyping+using+next-generation+DNA+sequencing+data.">A framework for variation discovery and genotyping using next-generation DNA sequencing data.</a> Nature Genetics. 43, 491-498 (2011).</li></ol>

The authors have nothing to disclose.

La presente procedura è un protocollo di estrazione del DNA ottimizzato che ha notevolmente migliorato la resa del DNA ad alto peso molecolare rispetto ai metodi standard, senza compromettere la qualità del DNA. La fase critica con l&#39;effetto più grande sulla resa più era punto 5.2, che comprende una fase di centrifugazione più a lungo durante precipitazione in etanolo di qualsiasi protocollo pubblicato recensito qui, tranne uno che non è stato ampiamente distribuito 11. Non sono stati rilevati cambi...

Ottenere DNA di alta qualità per gli studi genetici umani è essenziale nel processo di scoperta del gene della malattia. Sangue, anche se richiede una procedura invasiva e anche di essere più costoso di raccolta della saliva, è favorito per la creazione di linee cellulari immortalizzate come una fonte infinita di DNA, o iPSCs per studi funzionali, e, talvolta, il DNA del sangue viene utilizzato quando le linee cellulari non sono disponibili. Tuttavia, il prelievo di sangue richiede un flebotomo addestrato e il sangue ha una emivita più breve di saliva 1. DNA dalla saliva è meno costoso e più facile da ottenere, dal momento che può essere raccolto e inviato attraverso la posta elettronica, senza la necessità di un flebotomo, aumentando così i potenziali soggetti piscine ben oltre il bacino di utenza di ospedali e laboratori 2. Studio iscrizione può essere migliorata quando i soggetti hanno la possibilità di dare un campione di saliva al posto del sangue 3, 4. Preoccupazioni circa la quantità e la qualità del DNA dalla saliva possono aver limitato la sua diffusione di noie nonostante i numerosi studi recenti studi che mostrano l&#39;idoneità di tutta la saliva, con una media di 4,3 x 10 5 cellule per millilitro, per il test del DNA rispetto ai più tamponi buccali metodi che non abbiano conseguito notevoli quantità di saliva 2, 3, 4, 5, 6. Mentre una modesta letteratura esistente che mostra l&#39;idoneità di tutta la saliva DNA derivato per le applicazioni di genotipizzazione compresi i metodi basati su microarray 8, 9, 10, nessuno studio ha esaminato sequenziamento di nuova generazione (NGS). L&#39;obiettivo di ottimizzare l&#39;intero protocollo di estrazione del DNA della saliva è stato quello di massimizzare la quantità e la qualità per le applicazioni della genetica in un modo economicamente efficace che può essere facilmente implementato in laboratorio con reagenti e materiali di consumo comuni. Estrazione del DNA dalla saliva richiede diverse procedure: 1) raccolta e conservazione, 2) la lisi cellulare, 3) trattamento RNasi, 4) la precipitazione delle proteine, 5) precipitazione in etanolo, 6) reidratazione del DNA. La soluzione di DNA Stabilizzazione tampone, descrittoin precedenza 2, funzioni adeguatamente senza alterazione. Nessun tentativo di ottimizzare il trattamento RNasi e DNA fasi di reidratazione è stata fatta. Per ogni passo rimanente, diverse variabili che potrebbero influenzare il rendimento sono stati identificati. Ogni variabile è stato manipolato individualmente e miglioramento della resa e la qualità è stata valutata statisticamente. Per le variabili che sono stati mostrati per migliorare il rendimento e / o la qualità del DNA, i valori ottimali sono stati inclusi nel protocollo finale.

<table border="0" cellpadding="0" cellspacing="0" width="260">
	<tbody>
		<tr height="49">
			<td height="49" style="height:49px;width:88px;">15ml Centrifuge Tubes</td>
			<td style="width:88px;">Fisher</td>
			<td style="width:84px;">12-565-268</td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:88px;">Cell Lysis Solution</td>
			<td style="width:88px;">Qiagen</td>
			<td style="width:84px;">158908</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:88px;">Proteinase K</td>
			<td style="width:88px;">Sigma</td>
			<td style="width:84px;">P6556</td>
		</tr>
		<tr height="49">
			<td height="49" style="height:49px;width:88px;">Protein Precipitation Solution</td>
			<td style="width:88px;">Qiagen</td>
			<td style="width:84px;">158912</td>
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		<tr height="22">
			<td height="22" style="height:22px;width:88px;">Isopropanol</td>
			<td style="width:88px;">Fisher</td>
			<td style="width:84px;">A416-4</td>
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			<td height="33" style="height:33px;width:88px;">Glycogen</td>
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			<td height="22" style="height:22px;width:88px;">70% Ethanol</td>
			<td style="width:88px;">Fisher</td>
			<td style="width:84px;">04-355-305</td>
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			<td height="33" style="height:33px;width:88px;">Tris-EDTA (TE)</td>
			<td style="width:88px;">Fisher</td>
			<td style="width:84px;">BP2473-1</td>
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		<tr height="33">
			<td height="33" style="height:33px;width:88px;">NaCl</td>
			<td style="width:88px;">Fisher</td>
			<td style="width:84px;">AC194090010</td>
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		<tr height="22">
			<td height="22" style="height:22px;width:88px;">Tris HCl</td>
			<td style="width:88px;">Fisher</td>
			<td style="width:84px;">BP1757-100</td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:88px;">EDTA(0.5M) Solution</td>
			<td style="width:88px;">Fisher</td>
			<td style="width:84px;">03-500-506</td>
		</tr>
		<tr height="49">
			<td height="49" style="height:49px;width:88px;">Sodium Dodecyl Sulfate</td>
			<td style="width:88px;">Fisher</td>
			<td style="width:84px;">BP166-100&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;"></td>
			<td></td>
			<td></td>
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			<td></td>
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			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Equipment</td>
			<td></td>
			<td></td>
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			<td height="22" style="height:22px;"></td>
			<td></td>
			<td></td>
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		<tr height="43">
			<td height="43" style="height:43px;width:88px;">Name of Equipment</td>
			<td style="width:88px;">Distributor</td>
			<td style="width:84px;">Catalog#</td>
		</tr>
		<tr height="64">
			<td height="64" style="height:64px;width:88px;">Analog Vortex Mixer</td>
			<td style="width:88px;">Fisher</td>
			<td style="width:84px;">02-215-365</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:88px;">Centrifuge 5810R</td>
			<td style="width:88px;">Eppendorf</td>
			<td style="width:84px;">5811 000.010</td>
		</tr>
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</table>

collection and extraction of saliva dna for next generation sequencing

The preferred source of DNA in human genetics research is blood, or cell lines derived from blood, as these sources yield large quantities of high quality DNA. However, DNA extraction from saliva can yield high quality DNA with little to no degradation/fragmentation that is suitable for a variety of DNA assays without the expense of a phlebotomist and can even be acquired through the mail. However, at present, no saliva DNA collection/extraction protocols for next generation sequencing have been presented in the literature. This protocol optimizes parameters of saliva collection/storage and DNA extraction to be of sufficient quality and quantity for DNA assays with the highest standards, including microarray genotyping and next generation sequencing.

Per determinare i parametri ottimali per il DNA estrazione è stata effettuata una serie di estrazioni di DNA appaiati. Un singolo campione di saliva è stato diviso e ogni porzione sottoposta a uno dei due valori possibili per un dato variabile. Almeno otto repliche di ciascun test accoppiato state eseguite (ad esempio, un singolo campione di saliva è stato aliquotato per testare l&#39;estrazione con e senza iniziale 50 ° C incubazione). L&#39;ottimizzazione è basata su quattro metriche standard: rendimento...

Watch this Scientific Journal Video about Collection and Extraction of Saliva DNA for Next Generation Sequencing at JoVE.com

Collection and Extraction of Saliva DNA for Next Generation Sequencing

DNA extraction from saliva can provide a readily available source of high molecular weight DNA, with little to no degradation/fragmentation. This protocol provides optimized parameters for saliva collection/storage and DNA extraction to be of sufficient quality and quantity for downstream DNA assays with high quality requirements.

Raccolta ed estrazione di Saliva DNA per il sequenziamento di nuova generazione

The preferred source of DNA in human genetics research is blood, or cell lines derived from blood, as these sources yield large quantities of high quality ...

collection-and-extraction-of-saliva-dna-for-next-generation-sequencing

Research

JoVE Journal

Medicine

38.8K Views.  The Research Institute at Nationwide Children's Hospital. DNA extraction from saliva can provide a readily available source of high molecular weight DNA, with little to no degradation/fragmentation. This protocol provides optimized parameters for saliva collection/storage and DNA extraction to be of sufficient quality and quantity for downstream DNA assays with high quality requirements.

Video: Collection and Extraction of Saliva DNA for Next Generation Sequencing

Generation of Alginate Microspheres for Biomedical Applications

Alginate-based materials have received considerable attention for biomedical applications because of their hydrophilic nature, biocompatibility, and physical architecture. Applications include cell encapsulation, drug delivery, stem cell culture, and tissue engineering scaffolds. In fact, clinical trials are currently being performed in which islets are encapsulated in PLO coated alginate microbeads as a treatment of type I diabetes. However, large numbers of islets are required for efficacy due to poor survival following transplantation. The ability to locally stimulate microvascular network formation around the encapsulated cells may increase their viability through improved transport of oxygen, glucose and other vital nutrients. Fibroblast growth factor-1 (FGF-1) is a naturally occurring growth factor that is able to stimulate blood vessel formation and improve oxygen levels in ischemic tissues. The efficacy of FGF-1 is enhanced when it is delivered in a sustained fashion rather than a single large-bolus administration. The local long-term release of growth factors from islet encapsulation systems could stimulate the growth of blood vessels directly towards the transplanted cells, potentially improving functional graft outcomes. In this article, we outline procedures for the preparation of alginate microspheres for use in biomedical applications. In addition, we describe a method we developed for generating multilayered alginate microbeads. Cells can be encapsulated in the inner alginate core, and angiogenic proteins in the outer alginate layer. The release of proteins from this outer layer would stimulate the formation of local microvascular networks directly towards the transplanted islets.

In the following sections, we outline procedures for the preparation of alginate microspheres for use in biomedical applications. We specifically illustrate a technique for creating multilayered alginate microspheres for the dual purpose of cell and protein encapsulation as a potential treatment for type 1 diabetes.

Generazione di microsfere di alginato per applicazioni biomediche

Alginate-based materials have received considerable attention for biomedical applications because of their hydrophilic nature, biocompatibility, and ...

Ricerca

Medicina

The &alpha;-test: Rapid Cell-free CD4 Enumeration Using Whole Saliva

There is an urgent need for affordable CD4 enumeration to monitor HIV disease. CD4 enumeration is out of reach in resource-limited regions due to the time and temperature restrictions, technical sophistication, and cost of reagents, in particular monoclonal antibodies to measure CD4 on blood cells, the only currently acceptable method. A commonly used cost-saving and time-saving laboratory strategy is to calculate, rather than measure certain blood values. For example, LDL levels are calculated using the measured levels of total cholesterol, HDL, and triglycerides1. Thus, identification of cell-free correlates that directly regulate the number of CD4+ T cells could provide an accurate method for calculating CD4 counts due to the physiological relevance of the correlates.
The number of stem cells that enter blood and are destined to become circulating CD4+ T cells is determined by the chemokine CXCL12 and its receptor CXCR4 due to their influence on locomotion2. The process of stem cell locomotion into blood is additionally regulated by cell surface human leukocyte elastase (HLECS) and the HLECS-reactive active &alpha;1proteinase inhibitor (&alpha;1PI, &alpha;1antitrypsin, SerpinA1)3. In HIV-1 disease, &alpha;1PI is inactivated due to disease processes 4. In the early asymptomatic categories of HIV-1 disease, active &alpha;1PI was found to be below normal in 100% of untreated HIV-1 patients (median=12 &mu;M, and to achieve normal levels during the symptomatic categories4, 5. This pattern has been attributed to immune inactivation, not to insufficient synthesis, proteolytic inactivation, or oxygenation. We observed that in HIV-1 subjects with &gt;220 CD4 cells/&mu;l, CD4 counts were correlated with serum levels of active &alpha;1PI (r2=0.93, p&lt;0.0001, n=26) and inactive &alpha;1PI (r2=0.91, p&lt;0.0001, n=26) 5. Administration of &alpha;1PI to HIV-1 infected and uninfected subjects resulted in dramatic increases in CD4 counts suggesting &alpha;1PI participates in regulating the number of CD4+ T cells in blood 3.
With stimulation, whole saliva contains sufficient serous exudate (plasma containing proteinaceous material that passes through blood vessel walls into saliva) to allow measurement of active &alpha;1PI and the correlation of this measurement is evidence that it is an accurate method for calculating CD4 counts. Briefly, sialogogues such as chewing gum or citric acid stimulate the exudation of serum into whole mouth saliva. After stimulating serum exudation, the activity of serum &alpha;1PI in saliva is measured by its capacity to inhibit elastase activity. Porcine pancreatic elastase (PPE) is a readily available inexpensive source of elastase. PPE binds to &alpha;1PI forming a one-to-one complex that prevents PPE from cleaving its specific substrates, one of which is the colorimetric peptide, succinyl-L-Ala-L-Ala-L-Ala-p-nitroanilide (SA3NA). Incubating saliva with a saturating concentration of PPE for 10 min at room temperature allows the binding of PPE to all the active &alpha;1PI in saliva. The resulting inhibition of PPE by active &alpha;1PI can be measured by adding the PPE substrate SA3NA. (Figure 1). Although CD4 counts are measured in terms of blood volume (CD4 cells/&mu;l), the concentration of &alpha;1PI in saliva is related to the concentration of serum in saliva, not to volume of saliva since volume can vary considerably during the day and person to person6. However, virtually all the protein in saliva is due to serum content, and the protein content of saliva is measurable7. Thus, active &alpha;1PI in saliva is calculated as a ratio to saliva protein content and is termed the &alpha;1PI Index. Results presented herein demonstrate that the &alpha;1PI Index provides an accurate and precise physiologic method for calculating CD4 counts.

The &amp;#945;-test: Rapid Cell-free CD4 Enumeration Using Whole Saliva

A CD4 enumeration method, the &#x03B1;-test, is described which uses whole saliva to provide rapid and accurate CD4 counts. The &alpha;-test costs pennies and eliminates the need for technical training, costly reagents such as monoclonal antibodies, instrumentation, refrigeration, transport of samples, as well as collection and handling of blood.

La α-test: Rapid cell-free CD4 Enumeration Uso Saliva Whole

There is an urgent need for affordable CD4 enumeration to monitor HIV disease. CD4 enumeration is out of reach in resource-limited regions due to the time ...

Collection Protocol for Human Pancreas

This dissection and sampling procedure was developed for the Network for Pancreatic Organ Donors with Diabetes (nPOD) program to standardize preparation of pancreas recovered from cadaveric organ donors. The pancreas is divided into 3 main regions (head, body, tail) followed by serial transverse sections throughout the medial to lateral axis. Alternating sections are used for fixed paraffin and fresh frozen blocks and remnant samples are minced for snap frozen sample preparations, either with or without RNAse inhibitors, for DNA, RNA, or protein isolation. The overall goal of the pancreas dissection procedure is to sample the entire pancreas while maintaining anatomical orientation.
Endocrine cell heterogeneity in terms of islet composition, size, and numbers is reported for human islets compared to rodent islets 1. The majority of human islets from the pancreas head, body and tail regions are composed of insulin-containing &beta;-cells followed by lower proportions of glucagon-containing &alpha;-cells and somatostatin-containing &delta;-cells. Pancreatic polypeptide-containing PP cells and ghrelin-containing epsilon cells are also present but in small numbers. In contrast, the uncinate region contains islets that are primarily composed of pancreatic polypeptide-containing PP cells 2. These regional islet variations arise from developmental differences. The pancreas develops from the ventral and dorsal pancreatic buds in the foregut and after rotation of the stomach and duodenum, the ventral lobe moves and fuses with the dorsal 3. The ventral lobe forms the posterior portion of the head including the uncinate process while the dorsal lobe gives rise to the rest of the organ. Regional pancreatic variation is also reported with the tail region having higher islet density compared to other regions and the dorsal lobe-derived components undergoing selective atrophy in type 1 diabetes4,5.
Additional organs and tissues are often recovered from the organ donors and include pancreatic lymph nodes, spleen and non-pancreatic lymph nodes. These samples are recovered with similar formats as for the pancreas with the addition of isolation of cryopreserved cells. When the proximal duodenum is included with the pancreas, duodenal mucosa may be collected for paraffin and frozen blocks and minced snap frozen preparations.

This video demonstrates a dissection procedure for processing human pancreas into multiple storage formats. Anatomical orientation is maintained throughout the pancreatic regions to allow definition of regional islet composition and density.

Protocollo di raccolta per pancreas umano

This dissection and sampling procedure was developed for the Network for Pancreatic Organ Donors with Diabetes (nPOD) program to standardize preparation ...

Collecting Saliva and Measuring Salivary Cortisol and Alpha-amylase in Frail Community Residing Older Adults via Family Caregivers

Salivary measures have emerged in bio-behavioral research that are easy-to-collect, minimally invasive, and relatively inexpensive biologic markers of stress. This article we present the steps for collection and analysis of two salivary assays in research with frail, community residing older adults-salivary cortisol and salivary alpha amylase. The field of salivary bioscience is rapidly advancing and the purpose of this presentation is to provide an update on the developments for investigators interested in integrating these measures into research on aging. Strategies are presented for instructing family caregivers in collecting saliva in the home, and for conducting laboratory analyses of salivary analytes that have demonstrated feasibility, high compliance, and yield quality specimens. The protocol for sample collection includes: (1) consistent use of collection materials; (2) standardized methods that promote adherence and minimize subject burden; and (3) procedures for controlling certain confounding agents. We also provide strategies for laboratory analyses include: (1) saliva handling and processing; (2) salivary cortisol and salivary alpha amylase assay procedures; and (3) analytic considerations.

We demonstrate: (1) procedures for collection of salivary samples in cognitive impaired older adults by family caregivers in the home setting, (2) procedures for measuring stress activity via salivary cortisol and alpha amylase, and (3) representative profiles. Protocols that allow researchers to study stress-linked processes advance our understanding of biological sensitivity and susceptibility.

Salivary measures have emerged in bio-behavioral research  that are easy-to-collect, minimally invasive, and relatively inexpensive  biologic markers of ...

A Next-generation Tissue Microarray (ngTMA) Protocol for Biomarker Studies

Biomarker research relies on tissue microarrays (TMA). TMAs are produced by repeated transfer of small tissue cores from a &#8216;donor&#8217; block into a &#8216;recipient&#8217; block and then used for a variety of biomarker applications. The construction of conventional TMAs is labor intensive, imprecise, and time-consuming. Here, a protocol using next-generation Tissue Microarrays (ngTMA) is outlined. ngTMA is based on TMA planning and design, digital pathology, and automated tissue microarraying. The protocol is illustrated using an example of 134 metastatic colorectal cancer patients. Histological, statistical and logistical aspects are considered, such as the tissue type, specific histological regions, and cell types for inclusion in the TMA, the number of tissue spots, sample size, statistical analysis, and number of TMA copies. Histological slides for each patient are scanned and uploaded onto a web-based digital platform. There, they are viewed and annotated (marked) using a 0.6-2.0 mm diameter tool, multiple times using various colors to distinguish tissue areas. Donor blocks and 12 &#8216;recipient&#8217; blocks are loaded into the instrument. Digital slides are retrieved and matched to donor block images. Repeated arraying of annotated regions is automatically performed resulting in an ngTMA. In this example, six ngTMAs are planned containing six different tissue types/histological zones. Two copies of the ngTMAs are desired. Three to four slides for each patient are scanned; 3 scan runs are necessary and performed overnight. All slides are annotated; different colors are used to represent the different tissues/zones, namely tumor center, invasion front, tumor/stroma, lymph node metastases, liver metastases, and normal tissue. 17 annotations/case are made; time for annotation is 2-3 min/case. 12 ngTMAs are produced containing 4,556 spots. Arraying time is 15-20 hr. Due to its precision, flexibility and speed, ngTMA is a powerful tool to further improve the quality of TMAs used in clinical and translational research.

A Next-generation Tissue Microarray ngTMA Protocol for Biomarker Studies

The protocol aims at optimizing the construction and quality of tissue microarrays for biomarker research. It includes aspects of planning and design, digital pathology, virtual slide annotation, and automated tissue arraying.

Una nuova generazione Tissue Microarray (ngTMA) Protocollo per Biomarker Studi

Biomarker research relies on tissue microarrays (TMA). TMAs are produced by repeated transfer of small tissue cores from a &#8216;donor&#8217; block into ...

Integration of Wet and Dry Bench Processes Optimizes Targeted Next-generation Sequencing of Low-quality and Low-quantity Tumor Biopsies

All next-generation sequencing (NGS) procedures include assays performed at the laboratory bench (&#34;wet bench&#34;) and data analyses conducted using bioinformatics pipelines (&#34;dry bench&#34;). Both elements are essential to produce accurate and reliable results, which are particularly critical for clinical laboratories. Targeted NGS technologies have increasingly found favor in oncology applications to help advance precision medicine objectives, yet the methods often involve disconnected and variable wet and dry bench workflows and uncoordinated reagent sets. In this report, we describe a method for sequencing challenging cancer specimens with a 21-gene panel as an example of a comprehensive targeted NGS system. The system integrates functional DNA quantification and qualification, single-tube multiplexed PCR enrichment, and library purification and normalization using analytically-verified, single-source reagents with a standalone bioinformatics suite. As a result, accurate variant calls from low-quality and low-quantity formalin-fixed, paraffin-embedded (FFPE) and fine-needle aspiration (FNA) tumor biopsies can be achieved. The method can routinely assess cancer-associated variants from an input of 400 amplifiable DNA copies, and is modular in design to accommodate new gene content. Two different types of analytically-defined controls provide quality assurance and help safeguard call accuracy with clinically-relevant samples. A flexible &#34;tag&#34; PCR step embeds platform-specific adaptors and index codes to allow sample barcoding and compatibility with common benchtop NGS instruments. Importantly, the protocol is streamlined and can produce 24 sequence-ready libraries in a single day. Finally, the approach links wet and dry bench processes by incorporating pre-analytical sample quality control results directly into the variant calling algorithms to improve mutation detection accuracy and differentiate false-negative and indeterminate calls. This targeted NGS method uses advances in both wetware and software to achieve high-depth, multiplexed sequencing and sensitive analysis of heterogeneous cancer samples for diagnostic applications.

An integrated system for targeted next-generation sequencing of oncology specimens is described. This cross-platform system is optimized for low-quality and low-quantity tumor biopsies, accommodates low DNA inputs, includes well-characterized multi-variant controls, and features a novel variant caller that is informed by quantitative pre-analytical quality control measures.

Integrazione di Wet and Dry processi banco Ottimizza Targeted sequenziamento di prossima generazione di bassa qualità e di biopsie di tumori a bassa quantità

All next-generation sequencing (NGS) procedures include assays performed at the laboratory bench (&#34;wet bench&#34;) and data analyses conducted using ...

Estrazione economica del DNA di diatomee utilizzando un kit modificato

Extraction of Diatom DNA from Water Samples and Tissues

Diatom testing is an essential auxiliary means in forensic practice to determine whether the corpse drowned in water and to infer the drowning location. Diatom testing is also an important research content in the field of the environment and plankton. The diatom molecular biology testing technology, which focuses on diatom DNA as the primary research object, is a new method of diatom testing. Diatom DNA extraction is the basis of diatom molecular testing. At present, the kits commonly used for diatom DNA extraction are expensive, which increases the cost of carrying out related research. Our laboratory improved the general whole blood genomic DNA rapid extraction kit and obtained a satisfactory diatom DNA extraction effect, thus providing an alternative economical and affordable DNA extraction solution based on glass beads for related research. The diatom DNA extracted using this protocol could satisfy many downstream applications, such as PCR and sequencing.

Autore in primo piano: Test delle diatomee per l'esame forense dell'annegamento 

This article describes a protocol for diatom DNA extraction using a modified common DNA extraction kit.

Estrazione del DNA di diatomee da campioni d'acqua e tessuti

Diatom testing is an essential auxiliary means in forensic practice to determine whether the corpse drowned in water and to infer the drowning location. ...

Scoperta di biomarcatori non invasivi per la proteomica lacrimale mediante LC-MS

A Protein Suspension-Trapping Sample Preparation for Tear Proteomics by Liquid Chromatography-Tandem Mass Spectrometry

Tear fluid is one of the easily accessible biofluids that can be collected non-invasively. Tear proteomics has the potential to discover biomarkers for several ocular diseases and conditions. The suspension trapping column has been reported to be an efficient and user-friendly sample preparation workflow for the broad application of downstream proteomic analysis. Yet, this strategy has not been well-studied in the analysis of human tear proteome. The present protocol describes an integrated workflow from clinical human tear samples to purified peptides for non-invasive tear protein biomarker research using mass spectrometry, which provides insights into disease biomarkers and monitoring when combined with bioinformatics analysis. A protein suspension trapping sample preparation was applied and demonstrated the discovery of tear proteome with fast, reproducible, and user-friendly procedures, as a universal, optimized sample preparation for human tear fluid analysis. In particular, the suspension trapping procedure outperformed in-solution sample preparation in terms of peptide recovery, protein identification, and shorter sample preparation time.

Autore in primo piano: Avanzamento dell'analisi del fluido lacrimale utilizzando un protocollo standardizzato per la ricerca proteomica 

This protocol describes a method for collecting tear samples using Schirmer strips and an integrated quantitative workflow for discovering non-invasive tear protein biomarkers. The suspension trapping sample preparation workflow enables fast and robust tear sample preparation and mass spectrometric analysis, resulting in higher peptide recovery yields and protein identification than standard in-solution procedures.

Una preparazione del campione di intrappolamento della sospensione proteica per la proteomica lacrimale mediante cromatografia liquida-spettrometria di massa tandem

Tear fluid is one of the easily accessible biofluids that can be collected non-invasively. Tear proteomics has the potential to discover biomarkers for ...