Os autores agradecem à equipe do Centro de Medicina Comparada e Pesquisa (CCMR) em Dartmouth por seu cuidado especializado com os camundongos usados para esses estudos. O Bornstein Research Fund financiou esta pesquisa.

Os autores não têm nada a revelar.

Métodos para avaliar a composição celular no compartimento do SNC durante a homeostase e a doença são essenciais para a compreensão dos estados fisiológicos e patológicos do SNC. No entanto, apesar de servir como uma barreira importante no SNC e abrigar uma gama diversificada de células imunes, as meninges são frequentemente omitidas da análise porque muitos métodos convencionais de extração de tecidos para o cérebro e a medula espinhal não permitem a coleta dessas membranas. Essa omissão é uma limitaç...

O sistema nervoso central (SNC) é um sítio imunologicamente especializado. O parênquima do SNC, excluindo o espaço liquórico, as meninges e a vasculatura, é classicamente visto como um sítio imunoprivilegiado 1,2,3,4,5 e é relativamente desprovido de células imunes durante condições homeostáticas2,6,7. Em contraste, as meninges, compostas pelas camadas dura, aracnoide e pia, são componentes cruciais do compartimento do SNC, participando ativamente da vigilância imunológica homeostática e dos processos inflamatórios durante a patogênese da doença 3,6,7,8. Durante condições de estado estacionário, as meninges suportam numerosas células sentinelas imunes, incluindo células linfoides inatas (ILC), macrófagos, células dendríticas (DC), mastócitos, células T e, em menor grau, células B 9,10,11.
As meninges são estruturas altamente vascularizadas e contêm vasos linfáticos que fornecem uma conexão linfática entre o SNC e sua periferia8,12,13,14. Em condições inflamatórias induzidas por lesão do SNC, infecções, autoimunidade ou mesmo neurodegeneração, células imunes derivadas da periferia infiltram o parênquima e alteram a paisagem imune dentro das meninges. Após a infiltração celular, as meninges podem representar um nicho funcional para células imunes derivadas da periferia, promovendo agregação de células imunes, ativação de células imunes locais e sobrevivência a longo prazo no compartimento do SNC. Inflamação meníngea proeminente é observada em múltiplas doenças que afetam o SNC, incluindo esclerose múltipla (EM)15,16,17,18,19, acidente vascular cerebral 20,21, lesão estéril 22,23 (i.e., lesão medular e traumatismo cranioencefálico), enxaqueca 24 e infecção microbiana 25,26,27,28,29. Assim, a caracterização de células residentes e células imunes derivadas periféricas no compartimento meníngeo é essencial para a compreensão do papel dessas células durante condições de estado estacionário e patogênese da doença.
A extração do cérebro, medula espinhal e meninges do crânio e corpos vertebrais é tecnicamente desafiadora e demorada. Atualmente, não há técnicas disponíveis para a extração rápida do cérebro com as três camadas meníngeas intactas. Embora a laminectomia produza excelente morfologia do tecido medular e preserve as camadas meníngeas, é extremamente demorada e complicada30,31. Por outro lado, métodos de extração mais convencionais, como a remoção do cérebro do crânio e a extrusão hidráulica da medula espinhal, facilitam a rápida extração do tecido do SNC, mas tanto a meninge aracnoide quanto a dural são perdidas com essas técnicas30,31. A omissão das camadas dura-máter e aracnoide durante o isolamento convencional dos tecidos do cérebro e da medula espinhal resulta em uma análise incompleta das células dentro do compartimento do SNC. Assim, a identificação de novas técnicas focadas na extração rápida de tecidos do SNC com meninges intactas é crucial para a análise ótima do compartimento do SNC.
Este manuscrito apresenta dois métodos para a extração rápida do cérebro, medula espinhal e meninges de camundongos, facilitando a análise a jusante de células residentes e células imunes derivadas da periferia no parênquima do SNC e meninges. Esses protocolos otimizados concentram-se em 1) isolar suspensões unicelulares para análise a jusante e 2) preparar o tecido para processamento histológico. A obtenção de suspensões unicelulares do cérebro, tecido medular e meninges durais e aracnoides32 permite a análise simultânea de células residentes nos compartimentos parenquimatoso e meníngeo. Suspensões unicelulares podem ser usadas em diferentes aplicações, incluindo ensaios de cultura celular para realizar estimulação in vitro 33, imunospot ligado à enzima (ELISpot)28,34,35, citometria de fluxo 36,33 e transcriptômica de célula única 37 ou em massa. Além disso, o protocolo otimizado para descalcificação de cérebros inteiros e medula espinhal com crânios ou colunas vertebrais intactos, respectivamente, permite a descalcificação suave do osso circundante, deixando as meninges intactas e preservando a morfologia tecidual. Este método permite a identificação seletiva de proteínas ou RNA usando técnicas de imunohistoquímica (IHQ) ou hibridização in situ (HIS) dentro dos espaços parenquimatoso e meníngeo. A caracterização do fenótipo, estado de ativação e localização de células residentes e células imunes derivadas periféricas dentro do SNC pode fornecer informações essenciais para a compreensão de como tipos celulares individuais no compartimento do SNC contribuem para a homeostase e patogênese da doença.

<table>
	<tbody>
		<tr>
			<td>Aluminum foil</td>
			<td>any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin</td>
			<td>ThermoFisher Scientific</td>
			<td>37002D</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge</td>
			<td>Beckman Coulter</td>
			<td>Allegra X-12R centrifuge</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagenase I</td>
			<td>Worthington</td>
			<td>LS004196</td>
			<td></td>
		</tr>
		<tr>
			<td>Conical tube, 15 mL</td>
			<td>VWR</td>
			<td>525-1069</td>
			<td></td>
		</tr>
		<tr>
			<td>Conical tube, 50 mL</td>
			<td>VWR</td>
			<td>89039-658</td>
			<td></td>
		</tr>
		<tr>
			<td>Cover glass</td>
			<td>Hauser Scientific</td>
			<td>5000</td>
			<td></td>
		</tr>
		<tr>
			<td>Cryomold</td>
			<td>VWR</td>
			<td>18000-128</td>
			<td></td>
		</tr>
		<tr>
			<td>Curved forceps</td>
			<td>Fine Science Tools</td>
			<td>11003-14</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable polystyrene tube, 14 mL</td>
			<td>Fisher Scientific</td>
			<td>14-959-1B</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable Scalpel</td>
			<td>Fisher Scientific</td>
			<td>NC0595256</td>
			<td></td>
		</tr>
		<tr>
			<td>DNAse I</td>
			<td>Worthington</td>
			<td>LS002139</td>
			<td></td>
		</tr>
		<tr>
			<td>Dry ice</td>
			<td>Airgas</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Durmont #7Forceps</td>
			<td>Fine Science Tools</td>
			<td>11271-30</td>
			<td></td>
		</tr>
		<tr>
			<td>EDTA disodium salt dihydrate</td>
			<td>Amresco</td>
			<td>0105-500g</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol, 100%</td>
			<td>any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Hyclone</td>
			<td>SH30910.03</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter top tube, 5 mL</td>
			<td>VWR</td>
			<td>352235</td>
			<td></td>
		</tr>
		<tr>
			<td>Fixable viability stain 780</td>
			<td>Becton Dickinson</td>
			<td>565388</td>
			<td></td>
		</tr>
		<tr>
			<td>Flow cytometer</td>
			<td>Beckman Coulter</td>
			<td>Gallios</td>
			<td></td>
		</tr>
		<tr>
			<td>Glucose</td>
			<td>Fisher Chemical</td>
			<td>D16-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti-mouse IgG (488 conjugate)</td>
			<td>Jackson immunoresearch</td>
			<td>115-546-146</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti-mouse IgG (594 conjugate)</td>
			<td>Jackson immunoresearch</td>
			<td>115-586-146</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti-rabbit 488</td>
			<td>Jackson immunoresearch</td>
			<td>111-545-144</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti-rat 594</td>
			<td>Jackson immunoresearch</td>
			<td>112-585-167</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti-rat 650</td>
			<td>Jackson immunoresearch</td>
			<td>112-605-167</td>
			<td></td>
		</tr>
		<tr>
			<td>Hank&#39;s Balnced Salt Solution (HBSS)</td>
			<td>Corning</td>
			<td>21-020-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Hemacytometer</td>
			<td>Andwin Scientific</td>
			<td>02-671-51B</td>
			<td></td>
		</tr>
		<tr>
			<td>Hemostat</td>
			<td>Fine Science Tools</td>
			<td>13004-14</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES (N-2-hydroxyethylpiperazine-N-2-ethane sulfonic acid)</td>
			<td>ThermoFisher Scientific</td>
			<td>15630080</td>
			<td></td>
		</tr>
		<tr>
			<td>KCl</td>
			<td>Fisher chemical</td>
			<td>BP366-500</td>
			<td></td>
		</tr>
		<tr>
			<td>KH2PO4 (anhydrous)</td>
			<td>Sigma Aldrich</td>
			<td>P5655-100G</td>
			<td></td>
		</tr>
		<tr>
			<td>Liquid Nitrogen</td>
			<td>Airgas</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse FC block (CD16/32)</td>
			<td>Becton Dickinson</td>
			<td>553141</td>
			<td></td>
		</tr>
		<tr>
			<td>Na2HP04 (anhydrous)</td>
			<td>Fisher Chemical</td>
			<td>S374-500</td>
			<td></td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>Fisher chemical</td>
			<td>S671-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Needle, 25 gauge</td>
			<td>Becton Dickinson</td>
			<td>305122</td>
			<td></td>
		</tr>
		<tr>
			<td>Normal mouse serum</td>
			<td>ThermoFisher Scientific</td>
			<td>31881</td>
			<td></td>
		</tr>
		<tr>
			<td>Nylon mesh strainer</td>
			<td>VWR</td>
			<td>352350</td>
			<td></td>
		</tr>
		<tr>
			<td>OCT</td>
			<td>Sakura</td>
			<td>4583</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraformaldehyde, 20%</td>
			<td>Electron Microscopy Sciences</td>
			<td>15713-S</td>
			<td>Diluted to 4% using 1 x PBS</td>
		</tr>
		<tr>
			<td>Pasteur pipette, 9 inch, unplugged</td>
			<td>Fisher Scientific</td>
			<td>13-678-20C</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS (1x)</td>
			<td>Corning</td>
			<td>21-040-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>PE Rat Anti-Mouse CD4</td>
			<td>Becton Dickinson</td>
			<td>553730</td>
			<td></td>
		</tr>
		<tr>
			<td>PE-CF594 Rat Anti-Mouse CD19</td>
			<td>Becton Dickinson</td>
			<td>562329</td>
			<td></td>
		</tr>
		<tr>
			<td>Percoll density gradient media</td>
			<td>GE healthcare</td>
			<td>17-0891-01</td>
			<td></td>
		</tr>
		<tr>
			<td>PerCP-Cy5.5 Rat Anti-Mouse CD45</td>
			<td>Becton Dickinson</td>
			<td>550994</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dish, 100 mm</td>
			<td>VWR</td>
			<td>353003</td>
			<td></td>
		</tr>
		<tr>
			<td>pH meter</td>
			<td>Fisher Scientific</td>
			<td>13-636-AB150</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipet-Aid</td>
			<td>Drummond Scientific Corporation</td>
			<td>4-000-101</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipette 200 &#181;l</td>
			<td>Gilson</td>
			<td>FA10005M</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipette tips, 1 mL</td>
			<td>USA Scientific</td>
			<td>1111-2831</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipette tips, 200 &#181;l</td>
			<td>USA Scientific</td>
			<td>1111-1816</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipette, 1 mL</td>
			<td>Gilson</td>
			<td>FA10006M</td>
			<td></td>
		</tr>
		<tr>
			<td>Prolong Diamond mountant with DAPI</td>
			<td>ThermoFisher Scientific</td>
			<td>P36962</td>
			<td></td>
		</tr>
		<tr>
			<td>Purified Rat Anti-Mouse CD16/CD32</td>
			<td>Becton Dickinson</td>
			<td>553141</td>
			<td></td>
		</tr>
		<tr>
			<td>Rabbit anti-mouse CD3 (SP7 clone)</td>
			<td>Abcam</td>
			<td>ab16669</td>
			<td></td>
		</tr>
		<tr>
			<td>Rabbit anti-mouse laminin</td>
			<td>Abcam</td>
			<td>ab11575</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse ERT-R7</td>
			<td>Abcam</td>
			<td>ab51824</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI 1640</td>
			<td>Corning</td>
			<td>10-040-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipet, 1 mL</td>
			<td>VWR</td>
			<td>357521</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipet, 10 mL</td>
			<td>VWR</td>
			<td>357551</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipet, 5 mL</td>
			<td>VWR</td>
			<td>357543</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium hydroxide</td>
			<td>Fisher Scientific</td>
			<td>S318-100</td>
			<td></td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Fisher chemical</td>
			<td>S5-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Surgical scissors</td>
			<td>Fine Science Tools</td>
			<td>14001-16</td>
			<td></td>
		</tr>
		<tr>
			<td>Surgical scissors, extra fine</td>
			<td>Roboz</td>
			<td>RS-5882</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe, 10 mL</td>
			<td>Becton Dickinson</td>
			<td>302995</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe, 5 mL</td>
			<td>Becton Dickinson</td>
			<td>309646</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan blue</td>
			<td>Gibco</td>
			<td>15250-061</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum filter system</td>
			<td>Millipore</td>
			<td>20207749</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum flask</td>
			<td>Thomas Scientific</td>
			<td>5340-2L</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum in-line filter</td>
			<td>Pall Corporation</td>
			<td>4402</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum line</td>
			<td>Cole Palmer</td>
			<td>EW-06414-20</td>
			<td></td>
		</tr>
		<tr>
			<td>Water bath</td>
			<td>ThermoFisher Scientific</td>
			<td>Versa bath</td>
			<td></td>
		</tr>
	</tbody>
</table>

isolating central nervous system tissues and associated meninges for the downstream analysis of immune cells

O sistema nervoso central (SNC) é composto pelo cérebro e pela medula espinhal e é envolto pelas meninges, camadas membranosas que servem de barreira entre a periferia e o SNC. O SNC é um sítio imunologicamente especializado e, em condições de estado estacionário, o privilégio imunológico é mais evidente no parênquima do SNC. Em contraste, as meninges abrigam uma gama diversificada de células residentes, incluindo células imunes inatas e adaptativas. Durante condições inflamatórias desencadeadas por lesão do SNC, autoimunidade, infecção ou mesmo neurodegeneração, células imunes derivadas da periferia podem entrar no parênquima e se instalar dentro das meninges. Acredita-se que essas células realizem ações benéficas e prejudiciais durante a patogênese da doença do SNC. Apesar desse conhecimento, as meninges são frequentemente negligenciadas quando se analisa o compartimento do SNC, pois os métodos convencionais de extração tecidual do SNC omitem as camadas meníngeas. Este protocolo apresenta dois métodos distintos para o isolamento rápido de tecidos murinos do SNC (isto é, cérebro, medula espinhal e meninges) que são adequados para análise a jusante através de técnicas de célula única, imunohistoquímica e métodos de hibridização in situ. Os métodos descritos fornecem uma análise abrangente dos tecidos do SNC, ideal para avaliar o fenótipo, a função e a localização das células que ocupam o compartimento do SNC sob condições homeostáticas e durante a patogênese da doença.

Este experimento representativo teve como objetivo quantificar as células B e T e descrever a localização das células B e T nos compartimentos meníngeo e parenquimatoso do SNC em condições homeostáticas, bem como em um modelo murino de EM progressiva (i.e., IDD-TMEV). O DDI-TMEV foi induzido em camundongos SJL fêmeas com 5 semanas de idade por infecção intracraniana com 5 x 106 unidades formadoras de placa (UFP) de TMEV BeAn, conforme descrito anteriormente29.
<p class="j...

Watch this Scientific Journal Video about Isolating Central Nervous System Tissues and Associated Meninges for the Downstream Analysis of Immune cells at JoVE.com

Isolating Central Nervous System Tissues and Associated Meninges for the Downstream Analysis of Immune cells

Este artigo apresenta dois protocolos otimizados para examinar células imunes residentes e derivadas periféricas dentro do sistema nervoso central, incluindo cérebro, medula espinhal e meninges. Cada um desses protocolos ajuda a determinar a função e a composição das células que ocupam esses compartimentos em condições de estado estacionário e inflamatório.

Isolando Tecidos do Sistema Nervoso Central e Meninges Associadas para Análise a Jusante de Células Imunes

The central nervous system (CNS) is comprised of the brain and spinal cord and is enveloped by the meninges, membranous layers serving as a barrier ...

isolating-central-nervous-system-tissues-associated-meninges-for

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JoVE Journal

Immunology and Infection

8.8K visualizações.  Dartmouth-Hitchcock Medical Center. Este artigo apresenta dois protocolos otimizados para examinar células imunes residentes e derivadas periféricas dentro do sistema nervoso central, incluindo cérebro, medula espinhal e meninges. Cada um desses protocolos ajuda a determinar a função e a composição das células que ocupam esses compartimentos em condições de estado estacionário e inflamatório.

Vídeo: Isolating Central Nervous System Tissues and Associated Meninges for the Downstream Analysis of Immune cells

Flow Cytometry Analysis of Immune Cells Within Murine Aortas

Atherosclerosis is a chronic inflammatory process of medium and large size vessels that is characterized by the formation of plaques consisting of foam cells, immune cells, vascular endothelial and smooth muscle cells, platelets, extracellular matrix, and a lipid-rich core with extensive necrosis and fibrosis of surrounding tissues.1 The innate and adaptive arms of the immune response are involved in the initiation, development and persistence of atherosclerosis.2, 3 There is a significant body of evidence that different subsets of the immune cells, such as macrophages, dendritic cells, T and B lymphocytes, are present within the aortas of healthy and atherosclerosis-prone mice4. Additionally, immune cells are found in the surrounding aortic adventitia which suggests an important role of this tissue in atherogenesis.2
For some time, the quantitative detection of different types of immune cells, their activation status, and the cellular composition within the aortic wall was limited by RT-PCR and immunohistochemical methods for the study of atherosclerosis. Few attempts were made to perform flow cytometry using human aortas, and a number of problems, such as a high autofluorescence, have been reported5,6. Human atherosclerotic plaques were digested with collagenase 1, and free cells were collected and stained for CD14+/CD11c+ to highlight macrophage-derived foam cells. In this study, a "mock" channel was used to avoid false-positive staining.6 Necrotic materials accumulating during the digestion process give rise in a large amount of debris that generates a high autofluorescence in aortic samples. To resolve this problem, a panel of negative and positive controls has been proposed, but only double staining could be applied in these samples. We have developed a new flow cytometry-based method7 to analyze the immune cell composition and characterize the activation, proliferation, differentiation of immune cells in healthy and atherosclerosis-prone aorta. This method allows the investigation of the immune cell composition of the aortic wall and opens possibilities to use a broad spectrum of immunological methods for investigations of immune aspects of this disease.

This paper presents a flow cytometry-based method to investigate the immune composition of aortas. The paper also illustrates an additional technique that allows examining surrounding adventitia and vessel wall separately. This method opens possibilities to perform phenotypical analyses of aortic leukocytes and apply several immunological assays for atherosclerosis studies.

Análise por Citometria de fluxo das células imunológicas Dentro aortas murino

Atherosclerosis is a chronic inflammatory process of medium and large size vessels that is characterized by the formation of plaques consisting of foam ...

Imunologia e Infecção

Culturing Microglia from the Neonatal and Adult Central Nervous System

Microglia are the resident macrophage-like cells of the central nervous system (CNS) and, as such, have critically important roles in physiological and pathological processes such as CNS maturation in development, multiple sclerosis, and spinal cord injury. Microglia can be activated and recruited to action by neuronal injury or stimulation, such as axonal damage seen in MS or ischemic brain trauma resulting from stroke. These immunocompetent members of the CNS are also thought to have roles in synaptic plasticity under non-pathological conditions. We employ protocols for culturing microglia from the neonatal and adult tissues that are aimed to maximize the viable cell numbers while minimizing confounding variables, such as the presence of other CNS cell types and cell culture debris. We utilize large and easily discernable CNS components (e.g. cortex, spinal cord segments), which makes the entire process feasible and reproducible. The use of adult cells is a suitable alternative to the use of neonatal brain microglia, as many pathologies studied mainly affect the postnatal spinal cord. These culture systems are also useful for directly testing the effect of compounds that may either inhibit or promote microglial activation. Since microglial activation can shape the outcomes of disease in the adult CNS, there is a need for in vitro systems in which neonatal and adult microglia can be cultured and studied.

We outline methods for the efficient and quick isolation/culture of viable microglia from the neonatal cerebral cortex and adult spinal cord. The dissection and plating of cortical microglia can be accomplished within 90 minutes, with the subsequent microglial harvest taking place ~ 10 days following the initial dissection.

Microglia cultura do Sistema Nervoso Central Neonatal e Adulto

Microglia are the resident macrophage-like cells of the central nervous system (CNS) and, as such, have critically important roles in physiological and ...

Isolation and Flow Cytometric Analysis of Immune Cells from the Ischemic Mouse Brain

Ischemic stroke initiates a robust inflammatory response that starts in the intravascular compartment and involves rapid activation of brain resident cells. A key mechanism of this inflammatory response is the migration of circulating immune cells to the ischemic brain facilitated by chemokine release and increased endothelial adhesion molecule expression. Brain-invading leukocytes are well-known contributing to early-stage secondary ischemic injury, but their significance for the termination of inflammation and later brain repair has only recently been noticed.
Here, a simple protocol for the efficient isolation of immune cells from the ischemic mouse brain is provided. After transcardial perfusion, brain hemispheres are dissected and mechanically dissociated. Enzymatic digestion with Liberase&#160;is followed by density gradient (such as Percoll) centrifugation to remove myelin and cell debris. One major advantage of this protocol is the single-layer density gradient procedure which does not require time-consuming preparation of gradients and can be reliably performed. The approach yields highly reproducible cell counts per brain hemisphere and allows for measuring several flow cytometry panels in one biological replicate. Phenotypic characterization and quantification of brain-invading leukocytes after experimental stroke may contribute to a better understanding of their multifaceted roles in ischemic injury and repair.

Inflammation plays a central role in the pathogenesis of ischemic stroke. Increasing evidence suggests that it acts as a double-edged sword which exacerbates early brain injury, but also contributes to later repair. This protocol describes the isolation of immune cells from the ischemic brain and their subsequent flow cytometric phenotyping.

Isolamento e análise de citometria de fluxo de células imunes do cérebro isquêmico Rato

Ischemic stroke initiates a robust inflammatory response that starts in the intravascular compartment and involves rapid activation of brain resident ...

Induction of Experimental Autoimmune Encephalomyelitis in Mice and Evaluation of the Disease-dependent Distribution of Immune Cells in Various Tissues

Multiple sclerosis is presumed to be an inflammatory autoimmune disease, which is characterized by lesion formation in the central nervous system (CNS) resulting in cognitive and motor impairment. Experimental autoimmune encephalomyelitis (EAE) is a useful animal model of MS, because it is also characterized by lesion formation in the CNS, motor impairment and is also driven by autoimmune and inflammatory reactions. One of the EAE models is induced with a peptide derived from the myelin oligodendrocyte protein (MOG)35-55 in mice. The EAE mice develop a progressive disease course. This course is divided into three phases: the preclinical phase (day 0 - 9), the disease onset (day 10 - 11) and the acute phase (day 12 - 14). MS and EAE are induced by autoreactive T cells that infiltrate the CNS. These T cells secrete chemokines and cytokines which lead to the recruitment of further immune cells. Therefore, the immune cell distribution in the spinal cord during the three disease phases was investigated. To highlight the time point of the disease at which the activation/proliferation/accumulation of T cells, B cells and monocytes starts, the immune cell distribution in lymph nodes, spleen and blood was also assessed. Furthermore, the levels of several cytokines (IL-1&#946;, IL-6, IL-23, TNF&#945;, IFN&#947;) in the three disease phases were determined, to gain insight into the inflammatory processes of the disease. In conclusion, the data provide an overview of the functional profile of immune cells during EAE pathology.

This manuscript describes the methods for induction and scoring of the experimental autoimmune encephalomyelitis (EAE) model, together with the assessment of immune cell distribution and mRNA cytokine levels in lymph nodes, spleen, blood and spinal cord using flow cytometry and quantitative PCR, respectively, at various disease phases.

Indução de encefalomielite autoimune experimental em camundongos e avaliação da distribuição da doença dependente de células imunes em vários tecidos

Multiple sclerosis is presumed to be an inflammatory autoimmune disease, which is characterized by lesion formation in the central nervous system (CNS) ...

Qualitative and Quantitative Analysis of the Immune Synapse in the Human System Using Imaging Flow Cytometry

The immune synapse is the area of communication between T cells and antigen-presenting cells (APCs). T cells polarize surface receptors and proteins towards the immune synapse to assure a stable binding and signal exchange. Classical confocal, TIRF, or super-resolution microscopy have been used to study the immune synapse. Since these methods require manual image acquisition and time-consuming quantification, the imaging of rare events is challenging. Here, we describe a workflow that enables the morphological analysis of tens of thousands of cells. Immune synapses are induced between primary human T cells in pan-leukocyte preparations and Staphylococcus aureus enterotoxin B (SEB)-loaded Raji cells as APCs. Image acquisition is performed with imaging flow cytometry, also called In-Flow microscopy, which combines features of a flow cytometer and a fluorescence microscope. A complete gating strategy for identifying T cell/APC couples and analyzing the immune synapses is provided. As this workflow allows the analysis of immune synapses in unpurified pan-leukocyte preparations and hence requires only a small volume of blood (i.e., 1 mL), it can be applied to samples from patients. Importantly, several samples can be prepared, measured, and analyzed in parallel.

Here, we describe a complete workflow for the qualitative and quantitative analysis of immune synapses between primary human T cells and antigen-presenting cells. The method is based on imaging flow cytometry, which allows the acquisition and evaluation of several thousand cell images within a relatively short period of time.

Análise qualitativa e quantitativa de sinapse imunológica no sistema humano usando a imagem latente de citometria de fluxo

The immune synapse is the area of communication between T cells and antigen-presenting cells (APCs). T cells polarize surface receptors and proteins ...

Analysis of Microglia and Monocyte-derived Macrophages from the Central Nervous System by Flow Cytometry

Numerous studies have demonstrated the role of immune cells, in particular macrophages, in central nervous system (CNS) pathologies. There are two main macrophage populations in the CNS: (i) the microglia, which are the resident macrophages of the CNS and are derived from yolk sac progenitors during embryogenesis, and (ii) the monocyte-derived macrophages (MDM), which can infiltrate the CNS during disease and are derived from bone marrow progenitors. The roles of each macrophage subpopulation differ depending on the pathology being studied. Furthermore, there is no consensus on the histological markers or the distinguishing criteria used for these macrophage subpopulations. However, the analysis of the expression profiles of the CD11b and CD45 markers by flow cytometry allows us to distinguish the microglia (CD11b+CD45med) from the MDM (CD11b+CD45high). In this protocol, we show that the density gradient centrifugation and the flow cytometry analysis can be used to characterize these CNS macrophage subpopulations, and to study several markers of interest expressed by these cells as we recently published. Thus, this technique can further our understanding of the role of macrophages in mouse models of neurological diseases and can also be used to evaluate drug effects on these cells.

This protocol provides an analysis of the macrophage subpopulations in the adult mouse central nervous system by flow cytometry and is helpful for the study of multiple markers expressed by these cells.

Análise de Microglia e Macropagos derivados de Monócitos do Sistema Nervoso Central por Citometria de Fluxo

Numerous studies have demonstrated the role of immune cells, in particular macrophages, in central nervous system (CNS) pathologies. There are two main ...

Isolating Lymphocytes from the Mouse Small Intestinal Immune System

The intestinal immune system plays an essential role in maintaining the barrier function of the gastrointestinal tract by generating tolerant responses to dietary antigens and commensal bacteria while mounting effective immune responses to enteropathogenic microbes. In addition, it has become clear that local intestinal immunity has a profound impact on distant and systemic immunity. Therefore, it is important to study how an intestinal immune response is induced and what the immunologic outcome of the response is. Here, a detailed protocol is described for the isolation of lymphocytes from small intestine inductive sites like the gut-associated lymphoid tissue Peyer&#39;s patches and the draining mesenteric lymph nodes and effector sites like the lamina propria and the intestinal epithelium. This technique ensures isolation of a large numbers of lymphocytes from small intestinal tissues with optimal purity and viability and minimal cross compartmental contamination within acceptable time constraints. The technical capability to isolate lymphocytes and other immune cells from intestinal tissues enables the understanding of immune responses to gastrointestinal infections, cancers, and inflammatory diseases.

Here we describe a detailed protocol for the isolation of lymphocytes from the inductive sites including the gut-associated lymphoid tissue Peyer&#39;s patches and the draining mesenteric lymph nodes, and the effector sites including the lamina propria and the intestinal epithelium of the small intestinal immune system.

Isolando os linfócitos de rato pequeno Intestinal sistema imunológico

The intestinal immune system plays an essential role in maintaining the barrier function of the gastrointestinal tract by generating tolerant responses to ...

A Positioning Device for the Placement of Mice During Intranasal siRNA Delivery to the Central Nervous System

Intranasal (IN) drug delivery to the brain has emerged as a promising method to bypass the blood-brain barrier (BBB) for the delivery of drugs into the central nervous system (CNS). Recent studies demonstrate the use of a peptide, RVG9R, incorporating the minimal receptor-binding domain of the Rabies virus glycoprotein, in eliciting the delivery of siRNA into neurons in the brain. In this protocol, the peptide-siRNA formulation is delivered intranasally with a pipette in the dominant hand, while the anesthetized mouse is restrained by the scruff with the nondominant hand in a "head down-and-forward position" to avoid drainage into the lung and stomach upon inhalation. This precise gripping of mice can be learned but is not easy and requires practice and skill to result in effective CNS uptake. Furthermore, the process is long-drawn, requiring about 45 min for the administration of a total volume of ~20-30 &#181;L of solution in 1-2 &#181;L droplet volumes per inhalation, with 3-4 min rest periods between each inhalation. The objective of this study is to disclose a mouse positioning device that enables the appropriate placement of mice for efficient IN administration of the peptide-siRNA formulation. Multiple features are incorporated into the design of the device, such as four or eight positioning chairs with adjustable height and tilt to restrain anesthetized mice in the head down-and-forward position, enabling easy visualization of the mice's nares and a built-in heating pad to maintain the mice's body temperatures during the procedure. Importantly, the ability to treat four or eight mice simultaneously with RVG9R-siRNA complexes in this manner enables studies on a much quicker time scale, for the testing of an IN therapeutic siRNA approach. In conclusion, this device allows for appropriate and controlled mouse head positioning for IN application of RVG9R-siRNA and other therapeutic molecules, such as nanoparticles or antibodies, for CNS delivery.

Here, we present a protocol using a mouse positioning device that enables the appropriate placement of mice for the intranasal administration of a brain-targeting peptide-siRNA formulation enabling effective gene silencing in the central nervous system.

Um dispositivo de posicionamento para a colocação de camundongos durante a entrega de siRNA intranasal ao sistema nervoso central

Intranasal (IN) drug delivery to the brain has emerged as a promising method to bypass the blood-brain barrier (BBB) for the delivery of drugs into the ...

Flow Cytometric Analysis of Lymphocyte Infiltration in Central Nervous System during Experimental Autoimmune Encephalomyelitis

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) caused by the combination of environmental factors and susceptible genetic background. Experimental autoimmune encephalomyelitis (EAE) is a typical disease model of MS widely used for investigating the pathogenesis in which T lymphocytes specific for myelin antigens initiate an inflammatory reaction in CNS. It is very important to assess how lymphocytes in the CNS regulate the development of disease. However, the approach for measuring the quantity and quality of infiltrated lymphocytes in the CNS is very limited due to the difficulties in isolating and detecting infiltrated lymphocytes from the brain. This manuscript presents a protocol for that is useful for the isolation, identification, and characterization of infiltrated lymphocytes from the CNS and will be helpful for our understanding of how lymphocytes are involved in the development of the CNS autoimmune disease.

This manuscript presents a protocol to induce active experimental autoimmune encephalomyelitis (EAE) in mice. A method for the isolation and characterization of the infiltrated lymphocytes in the central nervous system (CNS) is also presented to show how lymphocytes are involved in the development of CNS autoimmune disease.

Análise Citométrica de Fluxo de Infiltração linfócito no Sistema Nervoso Central durante Encefalomielite Autoimune Experimental

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) caused by the combination of environmental factors and susceptible ...

Isolation of Mouse Kidney-Resident CD8+ T cells for Flow Cytometry Analysis

Tissue-resident memory T cell (TRM) is a rapidly expanding field of immunology research. Isolating T cells from various non-lymphoid tissues is one of the key steps to investigate TRMs. There are slight variations in lymphocyte isolation protocols for different organs. Kidney is an essential non-lymphoid organ with numerous immune cell infiltration especially after pathogen exposure or autoimmune activation. In recent years, multiple labs including our own have started characterizing kidney resident CD8+ T cells in various physiological and pathological settings in both mouse and human. Due to the abundance of T lymphocytes, kidney represents an attractive model organ to study TRMs in non-mucosal or non-barrier tissues. Here, we will describe a protocol commonly used in TRM-focused labs to isolate CD8+ T cells from mouse kidneys following systemic viral infection. Briefly, using an acute lymphocytic choriomeningitis virus (LCMV) infection model in C57BL/6 mice, we demonstrate intravascular CD8+ T cell labeling, enzymatic digestion, and density gradient centrifugation to isolate and enrich lymphocytes from mouse kidneys to make samples ready for the subsequent flow cytometry analysis.

Isolation of Mouse Kidney-Resident CD8+ T cells for Flow Cytometry Analysis

Following viral infection, kidney harbors a relatively large number of CD8+ T cells and offers an opportunity to study non-mucosal TRM cells. Here, we describe a protocol to isolate mouse kidney lymphocytes for flow cytometry analysis.

Isolamento das células CD8+ T residentes em rim do rato para análise de citometria de fluxo

Tissue-resident memory T cell (TRM) is a rapidly expanding field of immunology research. Isolating T cells from various non-lymphoid tissues is one of the ...