이 작품에 의해 지원 되었다 하트포드의 대학에서 대학 예술과 과학의 학장의 사무실에서 교수 연구 보조금.

연구 기간 동안 동물 보호 및 치료 건강의 국가 학회 정책 준수, 기관 지침에 따라 되었고 하트포드의 대학 동물 제도 동물 보호와 사용 위원회에 의해 승인 했다.
1입니다. 동물의 유입
참고: 20 주 된 남성 B6129SF2/J 쥐 연구에 사용 됩니다.
<ol><li>쥐 라이트 12 h (표준 오버 헤드 화이트 빛)를 끌고가 다/어두운 12 h 주기 2 주 전에 실험에 대 한. 참고: 여기 zeitgeber 시간 (ZT) 0 해당 하에 조명과 ZT12 조명, 다른 모든 환경 요인 (즉, 음식, 물, 그리고 실내 온도)를 유지 하면서 지속적인 21.</li>
</ol>2. 악기, 문화 매체, 및 도전 매체 준비
<ol><li>압력솥 집게와가 위 해입니다. 알루미늄 호 일 및 고압에 두르고 현미경 슬라이드의 쌍을 바꿈.</li>
	<li>10%의 최종 농도에 소 태아 혈 청 (FBS)를 추가 하 여 RPMI 1640 배양을 준비 합니다. 다음 PAMPs 문화 매체에 추가 하 여 10 mL 50 mL 튜브에 도전 매체의 준비 (RPMI 10 %FBS); LPS (5 µ g/mL), ODN1826 (5 µ g/mL), Listeria monocytogenes 열 사망 (108 HKLM/mL), 또는 다른 PAMP 제안된 농도에.</li>
	<li>문화 매체와 도전 매체 물 욕조에 37 ° C에 따뜻하고 실 온에서 약 70 mL의 멸 균 인산 염 버퍼 식 염 수 (PBS, pH 7.2) 계속.</li>
	<li>얼음에 10 mL 피 펫 및 50 mL 튜브를 피펫으로 원조를 사용 하 여 문화 매체의 10 mL를 추가 합니다.</li>
	<li>미생물 오염을 방지 하기 위해 비 커에가 위와 집게를 해 부의 100 mL 비 커와 장소 끝에 70% 에탄올의 약 30 mL를 추가 합니다.</li>
	<li>50 mL 튜브에 버퍼 실내의 모든 1 ml (후드 연기) 10 µ L β-Mercaptoethanol을 추가 하 여 RNA 격리에 대 한 세포의 용 해 버퍼 준비. 필요한 (600 µ L 당 약 1 x 106 셀로 구성 된 샘플) 될 금액만 확인 합니다. 참고: 버퍼 실내의 RNA 추출 키트 실리 카 막에 RNA의 바인딩을 지 원하는 구성 요소입니다.</li>
</ol>3. Splenocyte 절연 및 도전
<ol><li>그들의 원래 감 금 소에 그들을 유지 하 고 계속 호흡 중지 후 1 분 CO2 를 공급 3 L/분의 유량에 케이지를 CO2 를 추가 하 여 마 취 법을 통해 특정 zeitgeber 시간에 마우스를 안락사.</li>
	<li>두개골의 기지에서 목의 양쪽에 엄지와 검지 손가락을 배치 하 여 자 궁 경부 전위를 통해 죽음을 확인 합니다. 또는 눌러 두개골의 기지에서 막대 (를 사용 하 여 다른 손) 신속 하 게 당기면 꼬리 또는 두개골22에서 자 궁 경부 척추의 분리를 일으킬 뒷 다리 사지의 기지.</li>
	<li>70% 에탄올과 종이 타월로 닦아 마우스 트렁크를 스프레이. 다시 하 고 그것의 오른쪽으로 약간 기울어진에 마우스를 놓습니다. 버려야 모피, 해 부를 사용 하 여가 위, 마우스의 왼쪽된 측면을 따라에 대 한 중간 앞, 뒤 다리 사이.</li>
	<li>집게를 사용 하 여, 복을 신중 하 게 만들 비장의 손상 수 없습니다 절 개. 집게로 비장을 제거 하 고 얼음에 문화 미디어의 약 10 mL를 포함 하는 살 균 50ml 튜브에 배치. 나머지 동물에 대 한 반복 합니다. 참고: 비장은 신장 콩의 색상 이며 길고 신장 보다 아첨.</li>
	<li>
문화 매체의 2 mL와 함께 한 비장 작은 멸 균 페 트리 접시에 전송.
	<ol>
<li>두 메 마른 서 리 낀된 슬라이드의 젖 빛된 부분 사이 그것을 연마 하 여 비장을 균질. 만약에 가능 하다 면, 계속 문제 및 셀 매체에 균질 화 과정.</li>
		<li>일단 철저 하 게, 40 µ m 나일론 셀 스 트레이너를 통해 50 mL 튜브에는 splenocytes를 포함 하는 문화 매체의 2 개 mL를 피펫으로 무 균.</li>
		<li>나머지 spleens 문화 매체와 셀 멤브레인 두르고 슬라이드의 새로운 쌍, 50 mL 튜브를 사용 하 여 위의 단계를 반복 합니다.</li>
	</ol>
</li>
	<li>각각 10 mL/튜브의 전체 볼륨에 대 한 splenocytes를 포함 하는 50 mL 튜브의 감기 문화 매체의 8 mL를 추가 합니다. 당 밀리는 hemocytometer를 사용 하 여 셀의 개수를 결정 합니다.</li>
	<li>6 잘 배양 배지를 약 1 x 106 셀/잘을 추가 합니다. 셀 추가 실험을 위해 사용 되 고 다른 PAMPs의 번호에 해당 하는 컨트롤을 포함 하는 우물의 수를 잘 합니다. 각 우물에 문화 매체의 또는 도전 매체의 3 mL 3 mL를 추가 합니다.</li>
	<li>5% CO2 3 시간에서 37 ° C에서 번호판을 품 어.</li>
	<li>잘 사용 하 여 1000 µ L 피펫으로 팁 P1000 micropipette에 연결 된 아래에서 세포를 다쳤어요. 15 mL 튜브에 동일한 1000 µ L 피펫으로 팁을 사용 하 여 셀을 포함 하는 매체를 전송 합니다.</li>
	<li>실 온에서 5 분 동안 167 x g 에서 원심 분리를 통해 셀 작은 상쾌한을 제거 하 고 PBS의 5 mL와 함께 셀 펠 릿을 세척.</li>
	<li>작은 셀 5 분 동안 167 x g 에서 두 번째 시간, 상쾌한, 제거 하 고 셀 펠 릿을 위하여 세포를 lyse 세포의 용 해 버퍼의 600 µ L를 추가. 그런 다음 RNA 격리를 진행 합니다.</li>
</ol>4. RNA 분리 및 cDNA 합성
<ol><li>제조업체의 지침에 따라 RNA 추출 키트를 사용 하 여 splenocytes에서 RNA를 분리 하 고 '옵션'에 열 DNA 소화를 수행.</li>
	<li>CDNA 합성 전에 cDNA 합성 키트의 농도 범위 내에서 최적의 RNA (최대 2 µ g) 인지 확인 하는 microvolume 분 광 광도 계를 사용 하 여 RNA 농도 결정 합니다.</li>
	<li>
각 제조업체의 지침에 따라 역방향 전송 키트를 사용 하 여 샘플의 종합 cDNA. RNA의 10 µ L를 사용 하 여 각 20 µ L 총 반응 볼륨에서 샘플에 대 한. 반전 녹음 방송 (thermocycler 실행) 완료에 추가 20 μ H2O 각 반응에.
</li>
	<li>P10 또는 P20 micropipette 준비는 cDNA를 0.5 mL 튜브에는 몇 가지 컨트롤 샘플 (예를 들어, 5에서 10 µ L의 총 2 샘플 µ L)에서 mRNA를 풀을 사용 하 여 표준 커브를 생성 합니다.<ol>
<li>10 µ L 2 x 역전사 마스터 믹스를 추가 합니다.</li>
		<li>반전 녹음 방송의 완료에 표준 곡선에 대 한 희석 시리즈에 사용 시작 농도 ("1") 될 것입니다 반응 관에 H2O 10 µ L을 추가 합니다.</li>
		<li>P100 또는 P200 micropipette를 사용 하 여 지정 하는 10-1, 10-2, 10-3, 그리고 10-44 개의 0.5 mL 튜브에 물 45 µ L을 추가 하 여 10 희석 시리즈 (1 ~ 10-4)를 수행 합니다.<ol>
<li>P20 micropipettor, 아래로 pipetting으로 믹스를 사용 하 여 첫 번째 튜브 (10-1)에 "1" 시작 농도의 5 µ L를 추가, 여러 번 다음 튜브에 10-1 튜브에서 전송 5 µ L 지정 10-2 와 혼합.</li>
			<li>5 µ L 10-3 을 지정 하는 튜브에 10-2 관에서 P20 micropipette를 사용 하 여 전송 및 혼합. 5 µ L 10-4 지정 관에 10-3 관에서 P20 micropipettor를 사용 하 여 전송 및 혼합.</li>
		</ol>
</li>
	</ol>
</li>
</ol>5. 정량적 중 합 효소 연쇄 반응 (정량)
<ol><li>정량에 의해 mRNA 수준의 상대 정량을 확인 합니다. 내 실험에서 "정량-상대 표준 곡선" 및 "TaqMan" 화학을 선택. 변경 10 µ L. 반응 볼륨 플레이트 레이아웃 (예:대상 유전자, 표준 곡선, 기자, 등)에 관련 된 정보를 입력 합니다.</li>
	<li>0.5 µ L의 뇌관/조사 분석 결과, 유전자 표현 마스터 믹스의 5 µ L, H2O 2 µ L 및 2.5 포함 되도록 반응 준비 µ L의 cDNA (10-100 ng).<ol>
<li>반응, 표준 곡선에서 그들을 포함 하도록 확인 하 고 중복 계정을 2 추가 반응에서 각 반응이 수행 부정적인 컨트롤의 숫자에 의해 (cDNA)를 제외 하 고 위의 시 약의 각각 곱하여 마스터 믹스를 준비 대 한 pipetting 변화.</li>
		<li>피펫으로 7.5 µ L는 micropipette 또는 멀티 채널 피 펫 96-잘 반응 판에 미리 결정 된 우물에 준비 된 마스터 믹스의. 피펫으로 미지수 및 표준에 대 한 적절 한 우물에 cDNA의 2.5 µ L 및 2.5 µ L H2O 부정적인 제어 우물에의.</li>
		<li>다양 한 분자 시계 유전자에 대 한 입문서/조사 분석을 포함 하 고 또한 내 생 컨트롤 (예를 들어, β-말라)에 대 한 분석 결과 포함 합니다.</li>
	</ol>
</li>
	<li>상대 식 값을 결정 하기 위해 각 복제에 대 한 상대적인 평균 수량을 계산 후, 각 샘플에 대 한 β-걸에 대 한 평균 상대 수량으로 대상 유전자에 대 한 평균 상대 수량 분할.</li>
</ol>6. 통계 분석
<ol><li>통계 분석 소프트웨어를 사용 하 여 열 통계 옵션 아래 프로그램으로 데이터를 입력 합니다. 일방통행 ANOVA Dunnett의 포스트 hoc 테스트 컨트롤 대 PAMP 도전 후 시계 유전자 발현의 의미 값 간의 차이 평가 하기 위해 선택 합니다.</li>
</ol>

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C., Attarian, H., Videnovic, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circadian+rhythm+abnormalities.">Circadian rhythm abnormalities.</a> Contin. Lifelong Learn. Neurol. 19, 132-147 (2013).</li><li>Bovbjerg, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circadian+disruption+and+cancer:+sleep+and+immune+regulation.">Circadian disruption and cancer: sleep and immune regulation.</a> Brain. Behav. Immun. 17, 48-50 (2003).</li><li>Fu, L., Lee, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+circadian+clock:+pacemaker+and+tumour+suppressor.">The circadian clock: pacemaker and tumour suppressor.</a> Nat. Rev. Cancer. 3, 350-361 (2003).</li><li>Germain, A., Kupfer, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CIRCADIAN+RHYTHM+DISTURBANCES+IN+DEPRESSION.">CIRCADIAN RHYTHM DISTURBANCES IN DEPRESSION.</a> Hum. Psychopharmacol. 23, 571-585 (2008).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Basic+Mouse+Care+and+Maintenance.">Basic Mouse Care and Maintenance.</a> JoVE. , (2018).</li><li>Leary, 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=AVMA+Guidelines+for+the+Euthanasia+of+Animals+:+2013+Edition.">AVMA Guidelines for the Euthanasia of Animals : 2013 Edition.</a> AVMA. , (2013).</li><li>Silver, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogen-associated+molecular+patterns+alter+molecular+clock+gene+expression+in+mouse+splenocytes.">Pathogen-associated molecular patterns alter molecular clock gene expression in mouse splenocytes.</a> PLoS One. , 12-15 (2017).</li><li>Silver, A. C., 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=Daily+oscillations+in+expression+and+responsiveness+of+Toll-like+receptors+in+splenic+immune+cells.">Daily oscillations in expression and responsiveness of Toll-like receptors in splenic immune cells.</a> Heliyon. , 00579 (2018).</li></ol>

저자는 공개 상관이 있다.

이 프로토콜 내에서 계량 하 여 유전자 발현을 결정 하는데 사용 되는 RNA의 순도 평가 microvolume 분 광 광도 계를 사용할 수 있습니다. 260에 자외선을 흡수 하는 핵 산 nm, 일반적으로 280에 빛을 흡수 하는 단백질 nm, 다른 잠재적인 오염 물질 RNA 추출 절차 (예, 페 놀) 동안 사용 되는 230에서 감지 하는 동안 nm. 따라서, () 비율 260/280에서 흡 광도 평가 하 여 nm (단백질 RNA) 및 260/230 nm (비 단백질 오?...

생리학 및 행동의 거의 모든 측면에 대 한 24 시간 진동 총괄, 포유류, 마스터 클록은 시상 하 부1,2의 suprachiasmatic 핵 (SCN) 내에 있습니다. Organismal 수준에 생물학 과정을 통제, 이외 마스터 클록도 시체3,,45를 통해 주변 세포 시계를 동기화 합니다. 핵심 이루어져 있다 기간 (Per1-3), 신장의 (Cry1-2), Bmal1을 최소한 3 개의 맞물리는 transcriptional 변환 피드백 루프 분자 시계 기계 장치에 의하여 이루어져 있다, 하는 동안 그리고 시계 유전자6,7. 핵심 분자 시계의 정확한 타이밍을 유지, 게다가 일부 보조 시계 유전자 제품 (예, 레 브 erbα 및 Dbp) 또한 비 시계 유전자의 표현을 규제, 즉, 시계 제어 유전자 (CCGs)6 , 7.
기능성 분자 시계 다양 한 면역 조직 (예를 들어, 비장 및 림프절)8 셀 (예를 들어, B 세포, 수지상 세포, 대 식 세포)8,9에서 설명 했습니다. 이 세포를 감지 하 고 응답 병원 체 관련 된 분자 패턴 (PAMPs), 수용 체 통행세 같이 (TLRs)10등 타고 난 면역 인식 수용 체를 통해 보존된 미생물 구성 요소. 날짜 하려면, 13 기능 TLRs는 설명, 세균성 세포 벽 구성 요소, flagellar 단백질, 핵 산 미생물10등 미생물 성분 인식 하는. PAMP, lipopolysaccharide (LPS), TLR4에 의해 인식 하는 그람 음성 세균의 세포 벽 구성 요소 organismal와 분자 수준에서 circadian 리듬 변경 표시 되었습니다. 예를 들어 vivo에서 LPS의 빛 같은 위상 지연 마우스11 활동에 의해 측정 된 유도 도전과 SCN에 간 현장에서 교 잡 그리고 양이 많은 PCR에 의해 결정으로 감소 된 시계 유전자 발현에 쥐12에서 각각. vivo에서 도전 LPS와, 후 인간의 말 초 혈액 백혈구13 및 피하 지방 조직14 의 분석 통해 정량 측정으로 여러 시계 유전자의 바꾸 인된 표현을 밝혔다. 마지막으로, 인간의 세포와도 마우스 복 막 대 식 세포의 LPS 도전 비보 전 시계 식 정량14측정으로 변경.
여기, 우리 PAMPs LPS, ODN1826 (를 포함 하는 합성 oligonucleotides CpG 모티브 unmethylated)의 영향을 평가 하기 위해 프로토콜 설명 및 열 죽 Listeria monocytogenes (HKLM)에 의해 인식 TLR4, TLR9, 그리고 TLR2, 각각,에 분자 시계 유전자 식 마우스 splenocytes에. 프로토콜에는 마우스 splenectomy splenocyte 격리 및 도전, RNA 추출, cDNA 합성, 정량 여러 시계 유전자의 표정을 평가 하 포함 되어 있습니다. 이 프로토콜 면역 세포와 아주 작은 동물의 많은 수의 적시 취득 또는 세포 조작, 다음 수 있는 비보 전 다양 한 PAMPs와 도전. 분자 시계 변조 면역 응답8,,1516의 다양 한 측면을 보여줘 왔다, 그러므로, 분자 시계의 대부분의 적절 한 시간에 따른 변형 자유로울 것는 면역 응답입니다. 또한, 이후 circadian 리듬의 붕괴는 심각한 병 리17,18,,1920으로 이어질 수 있습니다., 그것은 연구자 도전 splenocytes의 넓은 범위에 대 한 관심의 있을 수 있습니다. 분자 시계에 그들의 영향을 평가 하 고.

<table><tbody><tr><td>Frosted slides</td><td>Fisher</td><td>12-550-343</td><td></td></tr><tr><td>Cell strainers</td><td>Fisher</td><td>22363547</td><td></td></tr><tr><td>Lipopolysaccharide&amp;nbsp;</td><td>InvivoGen</td><td>ltrl-eklps</td><td></td></tr><tr><td>ODN1826</td><td>InvivoGen</td><td>Tlrl-1826-1</td><td></td></tr><tr><td>HKLM</td><td>InvivoGen</td><td>Tlrl-hklm</td><td></td></tr><tr><td>RPMI 1640</td><td>Gibco</td><td>11875-093</td><td></td></tr><tr><td>PBS</td><td>Gibco</td><td>20012-043</td><td></td></tr><tr><td>RNeasy Mini Kit</td><td>Qiagen</td><td>74104 or 74106</td><td></td></tr><tr><td>RNase-Free DNase Set</td><td>Qiagen</td><td>79254</td><td></td></tr><tr><td>6-well cell culture plate</td><td>Denville</td><td>T1006</td><td></td></tr><tr><td>50 mL tubes</td><td>Corning</td><td>352070</td><td></td></tr><tr><td>15 mL tubes</td><td>Corning</td><td>352097</td><td></td></tr><tr><td>High Capacity cDNA Reverse Transcription Kit</td><td>ThermoFisher</td><td>4368814</td><td></td></tr><tr><td>TaqMan Gene Expression Assays b-actin</td><td>ThermoFisher</td><td>Mm00607939_s1</td><td></td></tr><tr><td>TaqMan Gene Expression Assays Per2</td><td>ThermoFisher</td><td>Mm00478113_m1</td><td></td></tr><tr><td>TaqMan Gene Expression Assays Rev-erba</td><td>ThermoFisher</td><td>Mm00520708_m1</td><td></td></tr><tr><td>TaqMan Gene Expression Assays Bmal1</td><td>ThermoFisher</td><td>Mm00500226_m1</td><td></td></tr><tr><td>TaqMan Gene Expression Assays Dbp</td><td>ThermoFisher</td><td>Mm00497539_m1</td><td></td></tr><tr><td>qPCR machine StepOnePlus</td><td>ThermoFisher</td><td></td><td></td></tr><tr><td>TaqMan Gene Expression Master Mix</td><td>ThermoFisher</td><td>4369016</td><td></td></tr><tr><td>MicroAmp Fast 96-well reaction plate (0.1 mL)</td><td>ThermoFisher</td><td>4346907</td><td></td></tr><tr><td>Statistical Analysis Software</td><td>Prism 7.0a</td><td></td><td></td></tr></tbody></table>

the use of mouse splenocytes to assess pathogen-associated molecular pattern influence on clock gene expression

유전자 발현을 행동, circadian 리듬 생리학의 거의 모든 측면을 통제 한다. 여기, 우리 병원 체 관련 된 분자 패턴 (PAMPs) lipopolysaccharide (LPS), ODN1826, 및 열 죽 Listeria monocytogenes 와 마우스 splenocytes 도전 circadian는 분자에 그들의 효과 검사 하는 방법론을 제시 시계입니다. 이전, 연구는 다양 한 모델 (예: 마우스, 쥐, 및 인간)의 구색에서 vivo에서 및 비보 전 접근을 사용 하 여 분자 시계에 LPS의 영향 검토에 집중 했다. 이 프로토콜에는 분리와 시계 유전자 식 후 도전 정량 PCR 통해 평가 하는 방법론으로 splenocytes, 도전 설명 합니다. 이 방법은 시계의 식 변경할 수 있는 다른 분자 뿐만 아니라 분자 시계에 미생물 구성 요소 뿐만 아니라 영향을 평가 하기 위해 사용할 수 있습니다. 이 이렇게 애타게 떨어져 어떻게 PAMP 통행세 같이 수용 체 상호 작용에 영향을 미치는 시계 식의 분자 메커니즘을 활용 될 수 있습니다.

마우스 ZT13에 희생 했다, splenocytes 고립 된 비보 전 PAMPs LPS, ODN1826, 또는 HKLM 도전. 3 h 후 RNA 격리, 고 정량 시계, Per2, Dbp, 및 레 브 erbα 당된 컨트롤 셀에 비해 분자 시계 유전자의 상대 식 수준을 평가 하는 데 사용 되었다. PAMP 도전 후 시계 식 레벨 제어 셀 (그림 1A) 식 보다 크게 다른 되지 않았습니?...

Watch this Scientific Journal Video about The Use of Mouse Splenocytes to Assess Pathogen-associated Molecular Pattern Influence on Clock Gene Expression at JoVE.com

The Use of Mouse Splenocytes to Assess Pathogen-associated Molecular Pattern Influence on Clock Gene Expression

이 프로토콜 마우스 splenocytes를 사용 하 여 분자 시계 유전자 발현을 변경 하는 병원 체 관련 된 분자 패턴을 검색 하는 기술을 설명 합니다.

병원 체 관련 된 분자 패턴 시계 유전자 발현에 영향을 평가 하기 위해 마우스 Splenocytes 사용 하 여

From behavior to gene expression, circadian rhythms regulate nearly all aspects of physiology. Here, we present a methodology to challenge mouse ...

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JoVE Journal

Genetics

7.4K 조회수.  University of Hartford. 이 프로토콜 마우스 splenocytes를 사용 하 여 분자 시계 유전자 발현을 변경 하는 병원 체 관련 된 분자 패턴을 검색 하는 기술을 설명 합니다.

비디오: The Use of Mouse Splenocytes to Assess Pathogen-associated Molecular Pattern Influence on Clock Gene Expression

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures

Circadian clocks are functional in all light-sensitive organisms, allowing for an adaptation to the external world by anticipating daily environmental changes. Considerable progress in our understanding of the tight connection between the circadian clock and most aspects of physiology has been made in the field over the last decade. However, unraveling the molecular basis that underlies the function of the circadian oscillator in humans stays of highest technical challenge. Here, we provide a detailed description of an experimental approach for long-term (2-5 days) bioluminescence recording and outflow medium collection in cultured human primary cells. For this purpose, we have transduced primary cells with a lentiviral luciferase reporter that is under control of a core clock gene promoter, which allows for the parallel assessment of hormone secretion and circadian bioluminescence. Furthermore, we describe the conditions for disrupting the circadian clock in primary human cells by transfecting siRNA targeting CLOCK. Our results on the circadian regulation of insulin secretion by human pancreatic islets, and myokine secretion by human skeletal muscle cells, are presented here to illustrate the application of this methodology. These settings can be used to study the molecular makeup of human peripheral clocks and to analyze their functional impact on primary cells under physiological or pathophysiological conditions.

Here, we describe settings to monitor in parallel circadian bioluminescence and the secretory activity of human islet cells and primary myotubes. For this, we employed lentiviral gene delivery of a luciferase core clock reporter, followed by in vitro synchronization and collection of outflow medium by continuous cell perifusion.

인간의 기본 세포 배양의 일주기 시계 유전자 발현 및 호르몬 분비의 병렬 측정

Circadian clocks are functional in all light-sensitive organisms, allowing for an adaptation to the external world by anticipating daily environmental ...

연구

유전학

In Vitro Bioluminescence Assay to Characterize Circadian Rhythm in Mammary Epithelial Cells

The circadian rhythm is a fundamental physiological process present in all organisms that regulates biological processes ranging from gene expression to sleep behavior. In vertebrates, circadian rhythm is controlled by a molecular oscillator that functions in both the suprachiasmatic nucleus (SCN; central pacemaker) and individual cells comprising most peripheral tissues. More importantly, disruption of circadian rhythm by exposure to light-at-night, environmental stressors and/or toxicants is associated with increased risk of chronic diseases and aging. The ability to identify agents that can disrupt central and/or peripheral biological clocks, and agents that can prevent or mitigate the effects of circadian disruption, has significant implications for prevention of chronic diseases. Although rodent models can be used to identify exposures and agents that induce or prevent/mitigate circadian disruption, these experiments require large numbers of animals. In vivo studies also require significant resources and infrastructure, and require researchers to work all night. Thus, there is an urgent need for a cell-type appropriate in vitro system to screen for environmental circadian disruptors and enhancers in cell types from different organs and disease states. We constructed a vector that drives transcription of the destabilized luciferase in eukaryotic cells under the control of the human PERIOD 2 gene promoter. This circadian reporter construct was stably transfected into human mammary epithelial cells, and circadian responsive reporter cells were selected to develop the in vitro bioluminescence assay. Here, we present a detailed protocol to establish and validate the assay. We further provide details for proof of concept experiments demonstrating the ability of our in vitro assay to recapitulate the in vivo effects of various chemicals on the cellular biological clock. The results indicate that the assay can be adapted to a variety of cell types to screen for both environmental disruptors and chemopreventive enhancers of circadian clocks.

In Vitro Bioluminescence Assay to Characterize Circadian Rhythm in Mammary Epithelial Cells

An in vitro bioluminescence assay to determine cellular circadian rhythm in mammary epithelial cells is presented. This method utilizes mammalian cell reporter plasmids expressing destabilized luciferase under the control of the PERIOD 2 gene promoter. It can be adapted to other cell types to evaluate organ-specific effects on circadian rhythm.

생체 외에서 유 방 상피 세포에서 Circadian 리듬 특성 분석 결과 생물 발광

The circadian rhythm is a fundamental physiological process present in all organisms that regulates biological processes ranging from gene expression to ...

Temporal Ordering of Dynamic Expression Data from Detailed Spatial Expression Maps

During somitogenesis, pairs of epithelial somites form in a progressive manner, budding off from the anterior end of the pre-somitic mesoderm (PSM) with a strict species-specific periodicity. The periodicity of the process is regulated by a molecular oscillator, known as the "segmentation clock," acting in the PSM cells. This clock drives the oscillatory patterns of gene expression across the PSM in a posterior-anterior direction. These so-called clock genes are key components of three signaling pathways: Wnt, Notch, and fibroblast growth factor (FGF). In addition, Notch signaling is essential for synchronizing intracellular oscillations in neighboring cells. We recently gained insight into how this may be mechanistically regulated. Upon ligand activation, the Notch receptor is cleaved, releasing the intracellular domain (NICD), which moves to the nucleus and regulates gene expression. NICD is highly labile, and its phosphorylation-dependent turnover acts to restrict Notch signaling. The profile of NICD production (and degradation) in the PSM is known to be oscillatory and to resemble that of a clock gene. We recently reported that both the Notch receptor and the Delta ligand, which mediate intercellular coupling, themselves exhibit dynamic expression at both the mRNA and protein levels. In this article, we describe the sensitive detection methods and detailed image analysis tools that we used, in combination with the computational modeling that we designed, to extract and overlay expression data from distinct points in the expression cycle. This allowed us to construct a spatio-temporal picture of the dynamic expression profile for the receptor, the ligand, and the Notch target clock genes throughout an oscillation cycle. Here, we describe the protocols used to generate and culture the PSM explants, as well as the procedure to stain for the mRNA or protein. We also explain how the confocal images were subsequently analyzed and temporally ordered computationally to generate ordered sequences of clock expression snapshots, hereafter defined as "kymographs," for the visualization of the spatiotemporal expression of Delta-like1 (Dll1) and Notch1 throughout the PSM.

The segmentation clock drives oscillatory gene expression across the pre-somitic mesoderm (PSM). Dynamic Notch activity is key to this process. We use imaging and computational analyses to extract temporal dynamics from spatial expression data to demonstrate that Delta ligand and Notch receptor expression oscillate in the vertebrate PSM.

자세한 공간 식지도에서 동적 식 데이터의 시간적 순서

During somitogenesis, pairs of epithelial somites form in a progressive manner, budding off from the anterior end of the pre-somitic mesoderm (PSM) with a ...

발생학

Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria

Pneumonia is one of the major health care problems in developing and industrialized countries and is associated with considerable morbidity and mortality. Despite advances in knowledge of this illness, the availability of intensive care units (ICU), and the use of potent antimicrobial agents and effective vaccines, the mortality rates remain high1. Streptococcus pneumoniae is the leading pathogen of community-acquired pneumonia (CAP) and one of the most common causes of bacteremia in humans. This pathogen is equipped with an armamentarium of surface-exposed adhesins and virulence factors contributing to pneumonia and invasive pneumococcal disease (IPD). The assessment of the in vivo role of bacterial fitness or virulence factors is of utmost importance to unravel S. pneumoniae pathogenicity mechanisms. Murine models of pneumonia, bacteremia, and meningitis are being used to determine the impact of pneumococcal factors at different stages of the infection. Here we describe a protocol to monitor in real-time pneumococcal dissemination in mice after intranasal or intraperitoneal infections with bioluminescent bacteria. The results show the multiplication and dissemination of pneumococci in the lower respiratory tract and blood, which can be visualized and evaluated using an imaging system and the accompanying analysis software.

Streptococcus pneumoniae is the leading pathogen causing severe community-acquired pneumonia and responsible for over 2&#160;million deaths worldwide. The impact of bacterial factors implicated in fitness or virulence can be monitored in real-time in an acute mouse pneumonia or bacteremia model using bioluminescent bacteria.

생물 발광 박테리아를 사용하여 실시간으로 급성 폐렴 마우스 모델에서 폐렴 구균 독성 요인의 영향에 따라

Pneumonia is one of the major health care problems in developing and industrialized countries and is associated with considerable morbidity and mortality. ...

면역학 및 감염병학

A Mouse Model for Pathogen-induced Chronic Inflammation at Local and Systemic Sites

Chronic inflammation is a major driver of pathological tissue damage and a unifying characteristic of many chronic diseases in humans including neoplastic, autoimmune, and chronic inflammatory diseases. Emerging evidence implicates pathogen-induced chronic inflammation in the development and progression of chronic diseases with a wide variety of clinical manifestations. Due to the complex and multifactorial etiology of chronic disease, designing experiments for proof of causality and the establishment of mechanistic links is nearly impossible in humans. An advantage of using animal models is that both genetic and environmental factors that may influence the course of a particular disease can be controlled. Thus, designing relevant animal models of infection represents a key step in identifying host and pathogen specific mechanisms that contribute to chronic inflammation.
Here we describe a mouse model of pathogen-induced chronic inflammation at local and systemic sites following infection with the oral pathogen Porphyromonas gingivalis, a bacterium closely associated with human periodontal disease. Oral infection of specific-pathogen free mice induces a local inflammatory response resulting in destruction of tooth supporting alveolar bone, a hallmark of periodontal disease. In an established mouse model of atherosclerosis, infection with P. gingivalis accelerates inflammatory plaque deposition within the aortic sinus and innominate artery, accompanied by activation of the vascular endothelium, an increased immune cell infiltrate, and elevated expression of inflammatory mediators within lesions. We detail methodologies for the assessment of inflammation at local and systemic sites. The use of transgenic mice and defined bacterial mutants makes this model particularly suitable for identifying both host and microbial factors involved in the initiation, progression, and outcome of disease. Additionally, the model can be used to screen for novel therapeutic strategies, including vaccination and pharmacological intervention.

Animal models have proven to be invaluable tools in defining host and pathogen specific mechanisms that contribute to the development of chronic inflammation. Here we describe a mouse model of oral infection with the human pathogen Porphyromonas gingivalis and detail methodologies to assess the progression of inflammation at local and systemic sites.

로컬 및 전신 사이트에서 병원체에 의한 만성 염증을위한 마우스 모델

Chronic inflammation is a major driver of pathological tissue damage and a unifying characteristic of many chronic diseases in humans including ...

Multiplex Cytokine Profiling of Stimulated Mouse Splenocytes Using a Cytometric Bead-based Immunoassay Platform

Bead-based immunoassays employ the same basic principle as sandwich immunoassays. Capture beads, which can be differentiated by size and internal allophycocyanin (APC) fluorescence intensity, are conjugated to antibodies specific to a particular analyte. Next, a selected panel of defined capture bead sets is incubated with a biological sample containing target analytes specific to the capture antibodies. A biotinylated detection antibody cocktail is added, which leads to the formation of capture bead-analyte-detection antibody sandwiches.
Finally, streptavidin-phycoerythrin (SA-PE) is added, which binds to biotinylated detection antibodies, providing fluorescent signal intensities in proportion to the amount of bound analyte. The PE fluorescent signal of analyte-specific beads regions is quantified using flow cytometry, and the concentrations of particular analytes are determined using data analysis software and the standard curve generated in the assay.
In this experiment, we use a mouse T helper cytokine panel to simultaneously quantify the concentration of 13 separate cytokine targets in tissue culture supernatants collected from mouse splenocytes cultured under various stimulatory conditions.

This protocol describes the quantification of multiple cytokine targets simultaneously in tissue culture supernatants collected from stimulated mouse splenocytes using multiplex bead based immunoassay platform and a flow cytometer.

Cytokine Profiling Immunoassay Cytometric 구슬-기반 플랫폼을 사용 하 여 자극된 마우스 Splenocytes의 다중화

Bead-based immunoassays employ the same basic principle as sandwich immunoassays. Capture beads, which can be differentiated by size and internal ...

Using a Bacterial Pathogen to Probe for Cellular and Organismic-level Host Responses

There are a variety of strategies bacterial pathogens employ to survive and proliferate once inside the eukaryotic cell. The so-called 'cytosolic' pathogens (Listeria monocytogenes, Shigella flexneri, Burkholderia pseudomallei, Francisella tularensis, and Rickettsia spp.) gain access to the infected cell cytosol by physically and enzymatically degrading the primary vacuolar membrane. Once in the cytosol, these pathogens both proliferate as well as generate sufficient mechanical forces to penetrate the plasma membrane of the host cell in order to infect new cells. Here, we show how this terminal step of the cellular infection cycle of L. monocytogenes (Lm) can be quantified by both colony-forming unit assays and flow cytometry and give examples of how both pathogen- and host-encoded factors impact this process. We also show a close correspondence of Lm infection dynamics of cultured cells infected in vitro and those of hepatic cells derived from mice infected in vivo. These function-based assays are relatively simple and can be readily scaled up for discovery-based high-throughput screens for modulators of eukaryotic cell function.

We describe both in vitro and in vivo infection assays that can be used to analyze the activities of host-encoding factors.

셀룰러 및 Organismic 수준 호스트 응답 세균성 병원 체 프로브를 사용 하 여

There are a variety of strategies bacterial pathogens employ to survive and proliferate once inside the eukaryotic cell. The so-called 'cytosolic' ...

In Vivo Monitoring of Circadian Clock Gene Expression in the Mouse Suprachiasmatic Nucleus Using Fluorescence Reporters

This technique combines optical fiber mediated fluorescence recordings with the precise delivery of recombinant adeno-associated virus based gene reporters. This new and easy to use in vivo fluorescence monitoring system was developed to record the transcriptional rhythm of the clock gene, Cry1, in the suprachiasmatic nucleus (SCN) of freely moving mice. To do so, a Cry1 transcription fluorescence reporter was designed and packaged into Adeno-associated virus. Purified, concentrated virus was injected into the mouse SCN followed by the insertion of an optic fiber, which was then fixed onto the surface of the brain. The animals were returned to their home cages and allowed a 1-month post-operative recovery period to ensure sufficient reporter expression. Fluorescence was then recorded in freely moving mice via an in vivo monitoring system that was constructed at our institution. For the in vivo recording system, a 488 nm laser was coupled with a 1 &#215; 4 beam-splitter that divided the light into four laser excitation outputs of equal power. This setup enabled us to record from four animals simultaneously. Each of the emitted fluorescence signals was collected via a photomultiplier tube and a data acquisition card. In contrast to the previous bioluminescence in vivo circadian clock recording technique, this fluorescence in vivo recording system allowed the recording of circadian clock gene expression during the light cycle.

In Vivo Monitoring of Circadian Clock Gene Expression in the Mouse Suprachiasmatic Nucleus Using Fluorescence Reporters

This newly developed fluorescence-based technology enables long-term monitoring of the transcription of circadian clock genes in the suprachiasmatic nucleus (SCN) of freely moving mice in real-time and at a high temporal resolution.

Vivo에서 형광 기자를 사용 하 여 마우스 Suprachiasmatic 핵에서 Circadian 시계 유전자 발현의 모니터링

This technique combines optical fiber mediated fluorescence recordings with the precise delivery of recombinant adeno-associated virus based gene ...

신경과학

Imaging of In Situ Interferon Gamma Production in the Mouse Spleen following Listeria monocytogenes Infection

Cytokines are small proteins secreted by cells, mediating cell-cell communications that are crucial for effective immune responses. One characteristic of cytokines is their pleiotropism, as they are produced by and can affect a multitude of cell types. As such, it is important to understand not only which cells are producing cytokines, but also in which environment they do so, in order to define more specific therapeutics. Here, we describe a method to visualize cytokine production in situ following bacterial infection. This technique relies on imaging cytokine-producing cells in their native environment by confocal microscopy. To do so, tissue sections are stained for markers of multiple cell types together with a cytokine stain. Key to this method, cytokine secretion is blocked directly in vivo before harvesting the tissue of interest, allowing for detection of the cytokine that accumulated inside the producing cells. The advantages of this method are multiple. First, the microenvironment in which cytokines are produced is preserved, which could ultimately inform on the signals required for cytokine production and the cells affected by those cytokines. In addition, this method gives an indication of the location of the cytokine production in vivo, as it does not rely on artificial in vitro re-stimulation of the producing cells. However, it is not possible to simultaneously analyze cytokine downstream signaling in cells that receive the cytokine. Similarly, the cytokine signals observed correspond&#160;only to the time-window during which cytokine secretion was blocked. While we describe the visualization of the cytokine Interferon (IFN) gamma in the spleen following mouse infection by the intracellular bacteria Listeria monocytogenes, this method could potentially be adapted to the visualization of any cytokine in most organs.

Imaging of In Situ Interferon Gamma Production in the Mouse Spleen following Listeria monocytogenes Infection

Here, we describe a simple confocal imaging method to visualize the in situ localization of cells secreting the cytokine Interferon gamma in murine secondary lymphoid organs. This protocol can be extended for the visualization of other cytokines in diverse tissues.

리스테리아 단세포 유전자 감염 다음 마우스 비장에서 시투 인터페론 감마 생산의 이미징

Cytokines are small proteins secreted by cells, mediating cell-cell communications that are crucial for effective immune responses. One characteristic of ...

Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters

In mammals, many aspects of behavior and physiology such as sleep-wake cycles and liver metabolism are regulated by endogenous circadian clocks (reviewed1,2). The circadian time-keeping system is a hierarchical multi-oscillator network, with the central clock located in the suprachiasmatic nucleus (SCN) synchronizing and coordinating extra-SCN and peripheral clocks elsewhere1,2. Individual cells are the functional units for generation and maintenance of circadian rhythms3,4, and these oscillators of different tissue types in the organism share a remarkably similar biochemical negative feedback mechanism. However, due to interactions at the neuronal network level in the SCN and through rhythmic, systemic cues at the organismal level, circadian rhythms at the organismal level are not necessarily cell-autonomous5-7. Compared to traditional studies of locomotor activity in vivo and SCN explants ex vivo, cell-based in vitro assays allow for discovery of cell-autonomous circadian defects5,8. Strategically, cell-based models are more experimentally tractable for phenotypic characterization and rapid discovery of basic clock mechanisms5,8-13.
Because circadian rhythms are dynamic, longitudinal measurements with high temporal resolution are needed to assess clock function. In recent years, real-time bioluminescence recording using firefly luciferase as a reporter has become a common technique for studying circadian rhythms in mammals14,15, as it allows for examination of the persistence and dynamics of molecular rhythms. To monitor cell-autonomous circadian rhythms of gene expression, luciferase reporters can be introduced into cells via transient transfection13,16,17 or stable transduction5,10,18,19. Here we describe a stable transduction protocol using lentivirus-mediated gene delivery. The lentiviral vector system is superior to traditional methods such as transient transfection and germline transmission because of its efficiency and versatility: it permits efficient delivery and stable integration into the host genome of both dividing and non-dividing cells20. Once a reporter cell line is established, the dynamics of clock function can be examined through bioluminescence recording. We first describe the generation of P(Per2)-dLuc reporter lines, and then present data from this and other circadian reporters. In these assays, 3T3 mouse fibroblasts and U2OS human osteosarcoma cells are used as cellular models. We also discuss various ways of using these clock models in circadian studies. Methods described here can be applied to a great variety of cell types to study the cellular and molecular basis of circadian clocks, and may prove useful in tackling problems in other biological systems.

Circadian clocks function within individual cells, i.e., they are cell-autonomous. Here, we describe methods for generating cell-autonomous clock models using non-invasive, luciferase-based real-time bioluminescence technology. Reporter cells provide tractable, functional model systems for studying circadian biology.