מחקר זה מומן על ידי צי מחקר רפואי מרכז, יחידת עבודת מחקר 6000.RAD1.J.A0310. הדעות המובאות במאמר זה הן של הכותבים ואינם מייצגים בהכרח את המדיניות הרשמית או עמדת מחלקת הצי, משרד ההגנה, או ממשלת ארצות הברית. ויי-מיי ג&#39;ינג הינו עובד של ממשלת ארה&quot;ב. עבודה זו הוכנה במסגרת תפקידיהם הרשמיים שלה. כותרת 17 USC §105 קובע כי &quot;הגנה על זכויות יוצרים תחת הכותרת הזו אינה זמינה עבור כל עבודה של ממשלת ארצות הברית.&quot; הכותרת 17 USC §101 מגדיר יצירת ממשלת ארה&quot;ב כיצירה שהכינה חבר או עובדים שירות צבאי של ממשלת ארה&quot;ב כחלק תפקידיו הרשמיים של אותו האדם.

.1 כן פלסמיד דנ&quot;א דילולים כתקן עבור תגובת LAMP <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> השתמש ספקטרופוטומטר למדידת צפיפות אופטית (OD) ב 260 ננומטר, כדי לקבוע את (IS1111a גן המטרה המכיל של ג burnetii RSA 493) פלסמיד ריכוז ה- DNA. OD של 260 של 1 משווה ל 50 מיקרוגרם / μl של ה- DNA. </li><li style=";text-align:right;direction:rtl"> המר את כמות ה- DNA פלסמיד לתוך מספר עותק. מאז בגודל של הפלסמיד הוא 6,330 נ&quot;ב, המשקל המולקולרי של פלסמיד זה הוא 4.1 x 10 6 גרם (6,330 נקודות בסיס x 649 ג &#39;/ נ&quot;ב). ריכוז ה- DNA של הפלסמיד הוא 34.2 ng / μl (כפי שנקבע משלב 1.1). 1 μl של דגימת DNA זה מכיל 34.2 ng של DNA פלסמיד, שהשוותה ל 5 x 10 9 עותקים (34.2 x 10 -9 גרם / 4.1 x 10 6 GX 6.02 x 10 23) של ה- DNA. </li><li style=";text-align:right;direction:rtl"> הוסף 10 μl של ה- DNA פלסמיד (5 x 10 9 עותקים / μl) עד 90 μl של מים עבור דילול של פי 10 לבצע דגימת DNA של 5 x 10 8 עותקים / μl. </li><li style=";text-align:right;direction:rtl"> חזור על שלב 1.3 להכין דגימות DNA של 5 x 10 7, 5 x 10 6, 5 x 10 5, 5 x 10 4, 5 x 10 3, 5 x 10 2, 5 x 10 1, ו -5 x 10 0 עותקים / μl. </li></ol> 2. הכן את ה- DNA תבנית ממדגמים עבור תגובת LAMP <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> בצע מיצוי דנ&quot;א מדגים מפלזמה אנושית באמצעות ערכת מיני DNA מסחרית על פי הפרוטוקול של היצרן. השתמש סך של 200 מדגם μl להפקת elute DNA חילוץ בהיקף 20 μl. </li></ol> 3. כן חיץ תגובת LAMP 2x <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> מערבבים 200 μl של 10x Pol הצפת, 320 μl של 5 M trimethylglycine, 12 μl של 1 M MgSO 4, 280 μl של תערובת dNTP (10 מ&quot;מ כל אחד) ו 188 μl של מים כדי להפוך 1 מ&quot;ל של חיץ 2x LAMP. מערבבים על ידי הדופק-vortexing במשך 10 שניות. </li></ol> 4. בצע התגובה הסטנדרטית LAMP <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> מערבבים 12.5 μl של 2x LAחיץ MP (כפי מוכן בשלב 3, 40 mM Tris-HCl (pH 8.8), 20 KCl מ&quot;מ, 16 מ&quot;מ 4 MgSO, 20 מ&quot;מ (NH 4) 2 4 SO, 0.2% Triton X-100, 1.6 M trimethylglycine, 1.4 מ&quot;מ dNTP תערובת), 1.2 μl של תמהיל פריימר, 1 μl של פולימראז BST DNA (8 U / μl), ו -5.3 μl של מים כדי להפוך תערובת התגובה (20 μl) בצינור 0.2 מ&quot;ל PCR. </li><li style=";text-align:right;direction:rtl"> הוסף 5 μl של ה- DNA (משלב 1 או 2) לתערובת התגובה 20 μl ומערבבים היטב. </li><li style=";text-align:right;direction:rtl"> צינור סגור לדגור על 60 מעלות צלזיוס במשך 60 דקות באמבט מים או בלוק חימום. זוהי טמפרטורת התגובה האופטימלית נקבעה בעבר. </li><li style=";text-align:right;direction:rtl"> הוסף 5 μl של 10x חיץ ג&#39;ל העמסה כדי לסיים את התגובה. </li><li style=";text-align:right;direction:rtl"> μl טען 5 של תוצרי התגובה כדי ג&#39;ל 2% agarose מוכתם intercalating כתם חומצות גרעין. </li><li style=";text-align:right;direction:rtl"> הפעל הג&#39;ל על 100 וולט במשך 35 דקות במאגר 1x TBE. </li><li style=";text-align:right;direction:rtl"> דמיינו את התוצאות על ידי אור UV. </li></ol> 5. בצע תגובת LAMP עם מחדשריאגנטים <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> מערבבים 125 μl של 10x Pol הצפת, 200 μl של 5 M trimethylglycine, 7.5 μl של 1 M MgSO 4, 667.5 μl של מים כדי להפוך 1 מ&quot;ל של חיץ הכינון מחדש. מערבבים על ידי הדופק-vortexing במשך 10 שניות. </li><li style=";text-align:right;direction:rtl"> הסר צינורות המכילים חומרים כימיים lyophilized מהשקית רדיד אלומיניום האטומה. אין להשתמש צינורות אם השקית בנייר אלומיניום אינו אטום או אם הוא פגום. </li><li style=";text-align:right;direction:rtl"> הוסף 20 μl של חיץ הכינון מחדש לתוך צינור אחד מחדש להשעות ריאגנטים lyophilized. </li><li style=";text-align:right;direction:rtl"> מערבבים על ידי pipetting למעלה חיץ ולמטה 5 פעמים. תסתכל לוודא ריאגנטים lyophilized מחדש תלויים לחלוטין. האבקה הלבנה צריכה להיעלם בצינור. </li><li style=";text-align:right;direction:rtl"> הוסף 5 μl של תבנית ה- DNA (משלב 1 או 2) אל ריאגנטים מחדש ומערבבים היטב. </li><li style=";text-align:right;direction:rtl"> צינור סגור לדגור על 60 מעלות צלזיוס במשך 60 דקות באמבט מים או בלוק חימום. </li><li style=";text-align:right;direction:rtl"> הוסף 5 μl של 10x חיץ ג&#39;ל העמסה כדי לסיים את התגובה. </li><li style=";text-align:right;direction:rtl"> טען 5 μl של תגובהמוצרים ג&#39;ל 2% agarose מוכתם intercalating כתם חומצות גרעין. </li><li style=";text-align:right;direction:rtl"> הפעל הג&#39;ל על 100 וולט במשך 35 דקות במאגר 1x TBE. </li><li style=";text-align:right;direction:rtl"> דמיינו את התוצאות על ידי אור UV. </li></ol> 6. בצע תגובת LAMP עם הצפת כינון המכילה HNB או פלורסנט intercalating דיי <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> מערבבים 125 μl של 10x Pol הצפת, 200 μl של 5 M trimethylglycine, 7.5 μl של 1 M 4 MgSO, 7.5 μl של 20 מ&quot;מ HNB (או 12.5 μl של 100x לצבוע intercalating פלורסנט) ו 660 μl (או 655 μl) של מים לעשות 1 מ&quot;ל של חיץ הכינון מחדש. מערבבים על ידי הדופק-vortexing במשך 10 שניות. </li><li style=";text-align:right;direction:rtl"> השתמש החיץ מחדש מוכן בסעיף 6 לחזור על השלבים 5.2 - 5.6. </li><li style=";text-align:right;direction:rtl"> דמיינו את התוצאות על ידי בעין בלתי המזוינת (תגובה המכילה HNB) או אור UV (תגובה המכילה לצבוע intercalating פלורסנט). </li></ol> 7. בצעו תגובת LAMP בזמן אמת עם סורק Tube <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> הוסף 5 μl DNA אל reconstitutריאגנטים ed המכיל לצבוע intercalating פלורסנט, צינור קרוב ולהכניס אותו לסורק צינור. </li><li style=";text-align:right;direction:rtl"> טמפרטורת דגירת גדר ב 60 ° C. למדוד את הקרינה ב 520 ננומטר במשך 60 דקות. </li></ol>

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בעבר, פיתחנו assay LAMP רגיש וספציפי מיקוד אלמנט הכניסה IS1111a 14. מרכיב IS1111 נבחר משום שהיא נשמרת מאוד בקרב הזנים השונים של C. burnetii ומספר גבוהים של עותקים (7 עד 110) החיידקים (קליי 2006). תוצאותינו הראו כי LAMP יכול לזהות כ -25 עותקים של אלמנט IS1111, אשר עשוי לתאם ק...

החיידק גראם שליליים קטנים Coxiella burnetii הוא הגורם הסיבתי של קדחת Q, שהינה זואונוסיס ברחבי העולם. בשל ההפצה העולמית של קדחת Q ואת ההדבקה גבוהה של ג burnetii, ארה&quot;ב אנשי צבאיים ואזרחיים בפריסה רב לאומית נמצאים בסיכון להידבק בתחומי אנדמיים. קדחת Q מבטאת בשתי צורות: זיהומים אקוטיים וכרוניים. Q-חום חריפה מציג את עצמו עם תסמינים דמויי שפעת, דלקת כבד, או דלקת ריאות, והוא בדרך כלל מחלה מעצמם עם שיעור תמותה נמוך. Q-חום כרוני, בעוד פחות נפוץ, לעתים קרובות תוצאות אנדוקרדיטיס, אשר יש שיעור תמותה גבוה בהרבה אם נותר 1,2 המטופל. לכן, אבחון מוקדם כדי להנחות את הטיפול מתאים הוא קריטי עבור טיפול בחולים. מבחני תגובת שרשרת פולימראז (PCR) בזמן אמת PCR כמותי (qPCR) פותחו לאיתור ג DNA burnetii בתרביות דגימות קליניות 3-5 &lt;/ Sup&gt;. שני PCR ו qPCR הם יקרים ולעתים קרובות לא זמינים באזורים מוגבל משאב לעבודה שגרתית. במקור שתאר Notomi 6, הגברת isothermal בתיווך לולאה (LAMP) מציעה שיטת הגברת DNA חלופית. LAMP משתמשת DNA פולימרז BST לסינתזת גדיל DNA עקירה יחד עם סטים פריימר ומעוצבים שמזהים לפחות לשישה אזורים עצמאיים של גן המטרה. היתרון המשמעותי ביותר של LAMP הוא הגברה מתרחשת בתנאי isothermal. לכן, רק באמבט מים, בלוק חימום או באינקובטור נדרש. שיטה זו נעשה שימוש כדי לזהות פתוגנים כמה ריקציאלי 7-9. ויזואליזציה של מוצרי ה- DNA מוגברים על ידי ג&#39;ל אלקטרופורזה היא השיטה המדויקת ביותר שיכול להבדיל חיוביות אמיתית תוצאות חיוביות שגויות עקב הגברה ספציפית. עם זאת בהליכי ג&#39;ל אלקטרופורזה אינם מעשיים עבור ar משאב מוגבלEAS. מספר שיטות חלופיות שפותחו כדי לגלות את תוצרי התגובה. חלופיים אלה, כגון עכירות נגזר היווצרות מגנזיום pyrophosphate 10 או באמצעות צבע intercalating פלורסנט להיות דמיינו תחת אור UV 11,12 הם נוחים יותר פועל ג&#39;ל. ריאגנטים LAMP היו יציבים במשך חודש, כאשר הם מאוחסנים על 25 מעלות צלזיוס ו -37 מעלות צלזיוס, אשר בטמפרטורות סביבה במדינות טרופיות ותת טרופיות שבו הקדחת Q היא 13 אנדמיים. Assay LAMP פותח במעבדה שלנו כדי לזהות את נוכחותו של ג burnetii בדגימות פלזמה 14. כאן אנו מתארים פרוטוקול פשוט להכנת תערובת התגובה LAMP מן ריאגנטים lyophilized. ריאגנטים lyophilized יציבים במשך חודש אחד, כאשר הם מאוחסנים ב RT. בשילוב עם שיטת הדמיה קלה, זוהי שיטה אידיאלית לשימוש לאיתור ג burnetii בסביבת משאב מוגבל.

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			<td height="26" style="height:27px;width:215px;">LAMP primers</td>
			<td style="width:188px;">Eurofins MWG operon</td>
			<td style="width:131px;">10 nmol, salt free</td>
			<td style="width:240px;">Sequence designed by customer</td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">Bst DNA polymerase</td>
			<td style="width:188px;">New England Biolabs</td>
			<td style="width:131px;">M0275L</td>
			<td style="width:240px;">8 units/ml</td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">10X Thermo pol buffer</td>
			<td style="width:188px;">New England Biolabs</td>
			<td style="width:131px;">B9004S</td>
			<td style="width:240px;"></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">dNTP mixture</td>
			<td style="width:188px;">New England Biolabs</td>
			<td style="width:131px;">N0447L</td>
			<td style="width:240px;">10 mM each</td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">Betaine</td>
			<td style="width:188px;">Sigma-Aldrich</td>
			<td style="width:131px;">B0300</td>
			<td style="width:240px;">5 M, Trimethylglycine</td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">Magnesium Sulfate</td>
			<td style="width:188px;">Sigma-Aldrich</td>
			<td style="width:131px;">M3409-1ML</td>
			<td style="width:240px;">1 M</td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">10X Bluejuice</td>
			<td style="width:188px;">Invitrogen</td>
			<td style="width:131px;">10816-015</td>
			<td style="width:240px;">gel loading buffer</td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">SYBR green</td>
			<td style="width:188px;">Invitrogen</td>
			<td style="width:131px;">S7585</td>
			<td style="width:240px;">10,000X, visualize products in tubes</td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">GelRed</td>
			<td style="width:188px;">Phenix Research Products</td>
			<td style="width:131px;">RGB-4103</td>
			<td style="width:240px;">10,000X, visualize products in gels</td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">Lyophilized reagents</td>
			<td style="width:188px;">Gene Reach</td>
			<td style="width:131px;"></td>
			<td style="width:240px;"></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">Hydroxynaphthol blue</td>
			<td style="width:188px;">Fluka</td>
			<td style="width:131px;">33936-10G</td>
			<td style="width:240px;"></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:215px;">ESEQuant tube scanner</td>
			<td style="width:188px;">Qiagen</td>
			<td style="width:131px;"></td>
			<td style="width:240px;">real-time detection</td>
		</tr>
	</tbody>
</table>

the development of lyophilized loop-mediated isothermal amplification reagents for the detection of coxiella burnetii

Burnetii Coxiella, סוכן גרימת הקדחת Q, הוא חיידק תאי לחייב. מבחני אבחון מבוסס PCR פותחו לאיתור ג DNA burnetii בתרביות דגימות קליניות. PCR דורש ציוד מיוחד והכשרת משתמש קצה נרחבת, ולכן, זה לא מתאים לעבודה שיגרתית במיוחד באזור המוגבל במשאבים. פתחנו הגברת isothermal בתיווך לולאה (LAMP) assay כדי לזהות את נוכחותו של ג burnetii בדגימות המטופל. שיטה זו מבוצעת בטמפרטורה יחידה סביב 60 מעלות צלזיוס באמבט מים או בלוק חימום. הרגישות של assay LAMP זה דומה מאוד PCR עם גבול גילוי של כ -25 עותקים לכל תגובה. דו&quot;ח זה מתאר את הכנת התגובה באמצעות ריאגנטים lyophilized ויזואליזציה של התוצאות באמצעות כחול hydroxynaphthol (HNB) או מנורת UV עם צבע intercalating פלורסנט התגובה. ריאגנטים LAMP היו lyophilized ו לאחסן בטמפרטורת החדר (RT) במשך חודש ללא הפסד של רגישות זיהוי. assay LAMP זהו חזק במיוחד משום הכנת תערובת התגובה אינה כרוך צעדים מורכבים. שיטה זו היא אידיאלית לשימוש הגדרות משאב מוגבל שבו קדחת Q הוא אנדמי.

ריאגנטים LAMP lyophilized בתוך הצינור 0.2 מ&quot;ל מכיל DNA פולימרז BST, תחל ו dNTPs. 20 μl של חיץ הכינון מחדש משמש מחדש להשעות את ריאגנטים lyophilized. איור 1 מציג את תוצאות התגובה LAMP על ג&#39;לים agarose עם ריאגנטים מוכן טרי ריאגנטים lyophilized. מגיב lyophilized לא לצמצם את פע?...

Watch this Scientific Journal Video about The Development of Lyophilized Loop-mediated Isothermal Amplification Reagents for the Detection of Coxiella burnetii at JoVE.com

The Development of Lyophilized Loop-mediated Isothermal Amplification Reagents for the Detection of Coxiella burnetii

התפתחות Lyophilized Loop בתיווך ריאגנטים הגברה איזו תרמים לצורך זיהוי של<em&gt; Burnetii Coxiella</em

We described here a simple loop-mediated isothermal amplification (LAMP) method using lyophilized reagents for the detection of C. burnetii in patient samples.

Coxiella burnetii, the agent causing Q fever, is an obligate intracellular bacterium. PCR based diagnostic assays have been developed for detecting C. ...

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Immunology and Infection

The Development of Lyophilized Loop-mediated Isothermal Amplification Reagents for the Detection of Coxiella burnetii

10.4K Views.  Naval Medical Research Center. We described here a simple loop-mediated isothermal amplification (LAMP) method using lyophilized reagents for the detection of C. burnetii in patient samples.

Video: The Development of Lyophilized Loop-mediated Isothermal Amplification Reagents for the Detection of Coxiella burnetii

Detection of Infectious Virus from Field-collected Mosquitoes by Vero Cell Culture Assay

Mosquitoes transmit a number of distinct viruses including important human pathogens such as West Nile virus, dengue virus, and chickungunya virus. Many of these viruses have intensified in their endemic ranges and expanded to new territories, necessitating effective surveillance and control programs to respond to these threats. One strategy to monitor virus activity involves collecting large numbers of mosquitoes from endemic sites and testing them for viral infection. In this article, we describe how to handle, process, and screen field-collected mosquitoes for infectious virus by Vero cell culture assay. Mosquitoes are sorted by trap location and species, and grouped into pools containing &le;50 individuals. Pooled specimens are homogenized in buffered saline using a mixer-mill and the aqueous phase is inoculated onto confluent Vero cell cultures (Clone E6). Cell cultures are monitored for cytopathic effect from days 3-7 post-inoculation and any viruses grown in cell culture are identified by the appropriate diagnostic assays. By utilizing this approach, we have isolated 9 different viruses from mosquitoes collected in Connecticut, USA, and among these, 5 are known to cause human disease. Three of these viruses (West Nile virus, Potosi virus, and La Crosse virus) represent new records for North America or the New England region since 1999. The ability to detect a wide diversity of viruses is critical to monitoring both established and newly emerging viruses in the mosquito population.

We describe a method to process and screen field-collected mosquitoes for a diversity of viruses by Vero cell culture assay. By employing this technique, we have detected 9 different viruses from 4 taxonomic families in mosquitoes collected in Connecticut.

איתור של וירוסים זיהומיות מהשטח, שנאספו על ידי יתושים Assay תרבות Vero Cell

Mosquitoes transmit a number of distinct viruses including important human pathogens such as West Nile virus, dengue virus, and chickungunya virus. Many ...

Generation of Recombinant Arenavirus for Vaccine Development in FDA-Approved Vero Cells

The development and implementation of arenavirus reverse genetics represents a significant breakthrough in the arenavirus field 4. The use of cell-based arenavirus minigenome systems together with the ability to generate recombinant infectious arenaviruses with predetermined mutations in their genomes has facilitated the investigation of the contribution of viral determinants to the different steps of the arenavirus life cycle, as well as virus-host interactions and mechanisms of arenavirus pathogenesis 1, 3, 11 . In addition, the development of trisegmented arenaviruses has permitted the use of the arenavirus genome to express additional foreign genes of interest, thus opening the possibility of arenavirus-based vaccine vector applications 5 . Likewise, the development of single-cycle infectious arenaviruses capable of expressing reporter genes provides a new experimental tool to improve the safety of research involving highly pathogenic human arenaviruses 16 . The generation of recombinant arenaviruses using plasmid-based reverse genetics techniques has so far relied on the use of rodent cell lines 7,19 , which poses some barriers for the development of Food and Drug Administration (FDA)-licensed vaccine or vaccine vectors. To overcome this obstacle, we describe here the efficient generation of recombinant arenaviruses in FDA-approved Vero cells.

Rescue of recombinant arenaviruses from cloned cDNAs, an approach referred to as reverse genetics, allows researchers to investigate the role of specific viral gene products, as well as the contribution of their different specific domains and residues, to many different aspects of the biology of arenavirus. Likewise, reverse genetics techniques in FDA-approved cell lines (Vero) for vaccine development provides novel possibilities for the generation of effective and safe vaccines to combat human pathogenic arenaviruses.

דור של Arenavirus רקומביננטי לפיתוח חיסון בתאי Vero-FDA

The development and implementation of arenavirus reverse genetics represents a significant breakthrough in the arenavirus field  4. The use of cell-based ...

Assessing the Development of Murine Plasmacytoid Dendritic Cells in Peyer's Patches Using Adoptive Transfer of Hematopoietic Progenitors

This protocol details a method to analyze the ability of purified hematopoietic progenitors to generate plasmacytoid dendritic cells (pDC) in intestinal Peyer&#39;s patch (PP). Common dendritic cell progenitors (CDPs, lin- c-kitlo CD115+ Flt3+) were purified from the bone marrow of C57BL6 mice by FACS and transferred to recipient mice that lack a significant pDC population in PP; in this case, Ifnar-/- mice were used as the transfer recipients. In some mice, overexpression of the dendritic cell growth factor Flt3 ligand (Flt3L) was enforced prior to adoptive transfer of CDPs, using hydrodynamic gene transfer (HGT) of Flt3L-encoding plasmid. Flt3L overexpression expands DC populations originating from transferred (or endogenous) hematopoietic progenitors. At 7-10 days after progenitor transfer, pDCs that arise from the adoptively transferred progenitors were distinguished from recipient cells on the basis of CD45 marker expression, with pDCs from transferred CDPs being CD45.1+ and recipients being CD45.2+. The ability of transferred CDPs to contribute to the pDC population in PP and to respond to Flt3L was evaluated by flow cytometry of PP single cell suspensions from recipient mice. This method may be used to test whether other progenitor populations are capable of generating PP pDCs. In addition, this approach could be used to examine the role of factors that are predicted to affect pDC development in PP, by transferring progenitor subsets with an appropriate knockdown, knockout or overexpression of the putative developmental factor and/or by manipulating circulating cytokines via HGT. This method may also allow analysis of how PP pDCs affect the frequency or function of other immune subsets in PPs. A unique feature of this method is the use of Ifnar-/- mice, which show severely depleted PP pDCs relative to wild type animals, thus allowing reconstitution of PP pDCs in the absence of confounding effects from lethal irradiation.

This protocol describes experimental procedures to assess the differentiation of plasmacytoid dendritic cells in Peyer&#8217;s patch from common dendritic cell progenitors, using techniques involving FACS-mediated cell isolation, hydrodynamic gene transfer, and flow analysis of immune subsets in Peyer&#8217;s patch.

הערכת התפתחותם של תאי Murine Plasmacytoid דנדריטים בתיקונים של Peyer באמצעות העברת מאמצת של אבות Hematopoietic

This protocol details a method to analyze the ability of purified hematopoietic progenitors to generate plasmacytoid dendritic cells (pDC) in intestinal ...

In Vitro Analysis of Myd88-mediated Cellular Immune Response to West Nile Virus Mutant Strain Infection

An attenuated West Nile virus (WNV), a nonstructural (NS) 4B-P38G mutant, induced higher innate cytokine and T cell responses than the wild-type WNV in mice. Recently, myeloid differentiation factor 88 (MyD88) signaling was shown to be important for initial T cell priming and memory T cell development during WNV NS4B-P38G mutant infection. In this study, two flow cytometry-based methods &#8211; an in vitro T cell priming assay and an intracellular cytokine staining (ICS) &#8211; were utilized to assess dendritic cells (DCs) and T cell functions. In the T cell priming assay, cell proliferation was analyzed by flow cytometry following co-culture of DCs from both groups of mice with carboxyfluorescein succinimidyl ester (CFSE) - labeled CD4+ T cells of OTII transgenic mice. This approach provided an accurate determination of the percentage of proliferating CD4+ T cells with significantly improved overall sensitivity than the traditional assays with radioactive reagents. A microcentrifuge tube system was used in both cell culture and cytokine staining procedures of the ICS protocol. Compared to the traditional tissue culture plate-based system, this modified procedure was easier to perform at biosafety level (BL) 3 facilities. Moreover, WNV- infected cells were treated with paraformaldehyde in both assays, which enabled further analysis outside BL3 facilities. Overall, these in vitro immunological assays can be used to efficiently assess cell-mediated immune responses during WNV infection.

In Vitro Analysis of Myd88-mediated Cellular Immune Response to West Nile Virus Mutant Strain Infection

Two flow cytometry-based methods &#8211; an in vitro T cell priming assay and intracellular cytokine staining were utilized to measure antigen presenting capacity of dendritic cells and antigen-specific T cell responses to a West Nile virus mutant infection in mice.

בניתוח חוץ גופייה של תיווך Myd88 הסלולרי תגובה החיסונית לוירוס הנילוס המערבי זיהום הזנים Mutant

An attenuated West Nile virus (WNV), a nonstructural (NS) 4B-P38G mutant, induced higher innate cytokine and T cell responses than the wild-type WNV in ...

Development of an in vitro model system for studying the interaction of Equus caballus IgE with its high-affinity receptor Fc&#949;RI

The interaction of IgE with its high-affinity Fc receptor (Fc&#949;RI) followed by an antigenic challenge is the principal pathway in IgE mediated allergic reactions. As a consequence of the high affinity binding between IgE and Fc&#949;RI, along with the continuous production of IgE by B cells, allergies usually persist throughout life, with currently no permanent cure available. Horses, especially race horses, which are commonly inbred, are a species of mammals that are very prone to the development of hypersensitivity responses, which can seriously affect their performance. Physiological responses to allergic sensitization in horses mirror that observed in humans and dogs. In this paper we describe the development of an in situ assay system for the quantitative assessment of the release of mediators of the allergic response pertaining to the equine system. To this end, the gene encoding equine Fc&#949;RI&#945; was transfected into and expressed onto the surface of parental Rat Basophil Leukemia (RBL-2H3.1) cells. The gene product of the transfected equine &#945;-chain formed a functional receptor complex with the endogenous rat &#946;- and &#947;-chains 1. The resultant assay system facilitated an assessment of the quantity of mediator secreted from equine Fc&#949;RI&#945; transfected RBL-2H3.1 cells following sensitization with equine IgE and antigenic challenge using &#946;-hexosaminidase release as a readout 2, 3. Mediator release peaked at 36.68% &#177; 4.88% at 100 ng ml-1 of antigen. This assay was modified from previous assays used to study human and canine allergic responses 4, 5. We have also shown that this type of assay system has multiple applications for the development of diagnostic tools and the safety assessment of potential therapeutic intervention strategies in allergic disease 6, 2, 3.

The current study describes the development and applications of a genetically engineered assay system based on the transfection of rat basophilic leukemia cells with the equine Fc&#949;RI&#945; gene. Transfected cells express a functional receptor where the release of mediators of the allergic response can be activated by IgE and antigen.

פיתוח<em&gt; במבחנה</em&gt; מערכת מודל לחקר האינטראקציה של<em&gt; Equus</em&gt;<em&gt; Caballus</em&gt; IgE עם קולטן גבוה הזיקה שלה FcεRI

The interaction of IgE with its high-affinity Fc receptor (Fc&#949;RI) followed by an antigenic challenge is the principal pathway in IgE mediated ...

Loop-mediated Isothermal Amplification (LAMP) Assays for the Species-specific Detection of Eimeria that Infect Chickens

Eimeria species parasites, protozoa which cause the enteric disease coccidiosis, pose a serious threat to the production and welfare of chickens. In the absence of effective control clinical coccidiosis can be devastating. Resistance to the chemoprophylactics frequently used to control Eimeria is common and sub-clinical infection is widespread, influencing feed conversion ratios and susceptibility to other pathogens such as Clostridium perfringens. Despite the availability of polymerase chain reaction (PCR)-based tools, diagnosis of Eimeria infection still relies almost entirely on traditional approaches such as lesion scoring and oocyst morphology, but neither is straightforward. Limitations of the existing molecular tools include the requirement for specialist equipment and difficulties accessing DNA as template. In response a simple field DNA preparation protocol and a panel of species-specific loop-mediated isothermal amplification (LAMP) assays have been developed for the seven Eimeria recognised to infect the chicken. We now provide a detailed protocol describing the preparation of genomic DNA from intestinal tissue collected post-mortem, followed by setup and readout of the LAMP assays. Eimeria species-specific LAMP can be used to monitor parasite occurrence, assessing the efficacy of a farm&#8217;s anticoccidial strategy, and to diagnose sub-clinical infection or clinical disease with particular value when expert surveillance is unavailable.

Loop-mediated Isothermal Amplification LAMP Assays for the Species-specific Detection of Eimeria that Infect Chickens

Diagnosis of Eimeria infection in chickens remains demanding. Parasite morphology- and host pathology-led approaches are commonly inconclusive, while molecular approaches based on PCR have proven demanding in cost and expertise. The aim of this protocol is to establish loop-mediated isothermal amplification (LAMP) as a straightforward molecular diagnostic for eimerian infection.

Isothermal הגברה מבחני בתיווך לולאה (LAMP) לאיתור המינים ספציפי של<em&gt; Eimeria</em&gt; כי להדביק תרנגולות

Eimeria species parasites, protozoa which cause the enteric disease coccidiosis, pose a serious threat to the production and welfare of chickens. In the ...

Generation and Multi-phenotypic High-content Screening of Coxiella burnetii Transposon Mutants

Invasion and colonization of host cells by bacterial pathogens depend on the activity of a large number of prokaryotic proteins, defined as virulence factors, which can subvert and manipulate key host functions. The study of host/pathogen interactions is therefore extremely important to understand bacterial infections and develop alternative strategies to counter infectious diseases. This approach however, requires the development of new high-throughput assays for the unbiased, automated identification and characterization of bacterial virulence determinants. Here, we describe a method for the generation of a GFP-tagged mutant library by transposon mutagenesis and the development of high-content screening approaches for the simultaneous identification of multiple transposon-associated phenotypes. Our working model is the intracellular bacterial pathogen Coxiellaburnetii, the etiological agent of the zoonosis Q fever, which is associated with severe outbreaks with a consequent health and economic burden. The obligate intracellular nature of this pathogen has, until recently, severely hampered the identification of bacterial factors involved in host pathogen interactions, making of Coxiella the ideal model for the implementation of high-throughput/high-content approaches.

Generation and Multi-phenotypic High-content Screening of Coxiella burnetii Transposon Mutants

Coxiella burnetii is an obligate intracellular Gram-negative bacterium responsible for the zoonotic disease Q fever. Here we describe methods for the generation of Coxiella fluorescent transposon mutants as well as the automated identification and analysis of the resulting internalization, replication and cytotoxic phenotypes.

דור והקרנה גבוהה תוכן רב-פנוטיפי של<em&gt; Burnetii Coxiella</em&gt; מוטאנטים טרנספוזון

Invasion and colonization of host cells by bacterial pathogens depend on the activity of a large number of prokaryotic proteins, defined as virulence ...

Qualitative and Quantitative Assays for Detection and Characterization of Protein Antimicrobials

Initial evaluations of large microbial libraries for potential producers of novel antimicrobial proteins require both qualitative and quantitative methods to screen for target enzymes prior to investing greater research effort and resources. The goal of this protocol is to demonstrate two complementary assays for conducting these initial evaluations. The microslide diffusion assay provides an initial or simple detection screen to enable the qualitative and rapid assessment of proteolytic activity against an array of both viable and heat-killed bacterial target substrates. As a counterpart, the increased sensitivity and reproducibility of the dye-release assay provides a quantitative platform for evaluating and comparing environmental influences affecting the hydrolytic activity of protein antimicrobials. The ability to label specific heat-killed cell culture substrates with Remazol brilliant blue R dye expands this capability to tailor the dye-release assay to characterize enzymatic activity of interest.

Here, we present protocols to rapidly screen and characterize enzymes for antimicrobial activity. The microslide diffusion assay and the dye-release assay utilize target bacterial substrates for qualitative and quantitative enzymatic activity evaluation.

מבחנים איכותיים וכמוני עבור זיהוי ואפיון של antimicrobials החלבון

Initial evaluations of large microbial libraries for potential producers of novel antimicrobial proteins require both qualitative and quantitative methods ...

Applying Fluorescence Resonance Energy Transfer (FRET) to Examine Effector Translocation Efficiency by Coxiella burnetii during siRNA Silencing

Coxiella burnetii, the causative agent of Q fever, is an intracellular pathogen that relies on a Type IV Dot/Icm Secretion System to establish a replicative niche. A cohort of effectors are translocated through this system into the host cell to manipulate host processes and allow the establishment of a unique lysosome-derived vacuole for replication. The method presented here involves the combination of two well-established techniques: specific gene silencing using siRNA and measurement of effector translocation using a FRET-based substrate that relies on &#946;-lactamase activity. Applying these two approaches, we can begin to understand the role of host factors in bacterial secretion system function and effector translocation. In this study we examined the role of Rab5A and Rab7A, both important regulators of the endocytic trafficking pathway. We demonstrate that silencing the expression of either protein results in a decrease in effector translocation efficiency. These methods can be easily modified to examine other intracellular and extracellular pathogens that also utilize secretion systems. In this way, a global picture of host factors involved in bacterial effector translocation may be revealed.

Applying Fluorescence Resonance Energy Transfer FRET to Examine Effector Translocation Efficiency by Coxiella burnetii during siRNA Silencing

Investigating the interactions between bacterial pathogens and their hosts is an important area of biological research. Here, we describe the necessary techniques to measure effector translocation by Coxiella burnetii during siRNA gene silencing using BlaM substrate.

החלת העברת אנרגית תהודת קרינה (סריג) לבחינת יעילות טרנסלוקציה מפעיל ידי<em&gt; Burnetii Coxiella</em&gt; במהלך siRNA השתקה

Coxiella burnetii, the causative agent of Q fever, is an intracellular pathogen that relies on a Type IV Dot/Icm Secretion System to establish a ...

Development of a More Sensitive and Specific Chromogenic Agar Medium for the Detection of Vibrio parahaemolyticus and Other Vibrio Species

Foodborne infections in the US caused by Vibrio species have shown an upward trend. In the genus Vibrio, V. parahaemolyticus is responsible for the majority of Vibrio-associated infections. Thus, accurate differentiation among Vibrio spp. and detection of V. parahaemolyticus is critically important to ensure the safety of our food supply. Although molecular techniques are increasingly common, culture-depending methods are still routinely done and they are considered standard methods in certain circumstances. Hence, a novel chromogenic agar medium was tested with the goal of providing a better method for isolation and differentiation of clinically relevant Vibrio spp. The protocol compared the sensitivity, specificity and detection limit for the detection of V. parahaemolyticus between the new chromogenic medium and a conventional medium. Various V. parahaemolyticus strains (n=22) representing diverse serotypes and source of origins were used. They were previously identified by Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC), and further verified in our laboratory by tlh-PCR. In at least four separate trials, these strains were inoculated on the chromogenic agar and thiosulfate-citrate-bile salts-sucrose (TCBS) agar, which is the recommended medium for culturing this species, followed by incubation at 35-37 &#176;C for 24-96 hr. Three V. parahaemolyticus strains (13.6%) did not grow optimally on TCBS, nonetheless exhibited green colonies if there was growth. Two strains (9.1%) did not yield the expected cyan colonies on the chromogenic agar. Non-V. parahaemolyticus strains (n=32) were also tested to determine the specificity of the chromogenic agar. Among these strains, 31 did not grow or exhibited other colony morphologies. The mean recovery of V. parahaemolyticus on the chromogenic agar was ~96.4% relative to tryptic soy agar supplemented with 2% NaCl. In conclusion, the new chromogenic agar is an effective medium to detect V. parahaemolyticus and to differentiate it from other vibrios.

Development of a More Sensitive and Specific Chromogenic Agar Medium for the Detection of Vibrio parahaemolyticus and Other Vibrio Species

Detection and isolation of clinically relevant Vibrio species require selective and differential culture media. This study evaluated the ability of a new chromogenic medium to detect and identify V. parahaemolyticus and other related species. The new medium was found to have better sensitivity and specificity than the conventional medium.

פיתוח בינוני אגר chromogenic רגיש וספציפי יותר לצורך זיהוי של<em&gt; Parahaemolyticus Vibrio</em&gt; ו אחר<em&gt; Vibrio</em&gt; מינים

Foodborne infections in the US caused by Vibrio species have shown an upward trend. In the genus Vibrio, V. parahaemolyticus is responsible for the ...