Name: evaluation of t follicular helper cells and germinal center response during influenza a virus infection in mice
Uploaded: 2020-06-27T13:00:00
Description: Watch this Scientific Journal Video about Evaluation of T Follicular Helper Cells and Germinal Center Response During Influenza A Virus Infection in Mice at JoVE.com

We thank the staffs of flow cytometry facility, ABSL2 facility and SPF animal facility of Institut Pasteur of Shanghai for their technical help and advice. This work was supported by the following grants: Strategic Priority Research Program of the Chinese Academy of Sciences (XDB29030103), National Key R&#38;D Program of China (2016YFA0502202), the National Natural Science Foundation of China (31570886).

Animal experiments were approved by the Institutional Animal Care and Use Committee of Institut Pasteur of Shanghai, China. All the experiments were performed based on the Institutional Animal Care and Use Committee-approved animal protocols.
NOTE: Virus infection of mice and isolation of organs should be performed under ABSL2 condition.
1. Inoculation of PR8 influenza virus and recording of mice weight
<ol>
	<li>Prepare 8-week-old male C57BL/6 mi...

<ol>
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Due to specialized roles in providing B-cell help for generating high-affinity antibodies, Tfh cells have been extensively studied in the mechanisms of differentiation and manipulation to provide new strategies for vaccine design. Influenza virus infection induces vigorous Tfh and GC B cells responses, thus being an appropriate model for this field of research. In this paper, we described protocols of influenza virus infection by intranasal inoculation, evaluation of Tfh-associated response by flow cytometry, immunofluor...

In the recent decade, numerous studies have been focused on the newly identified CD4+ T cell subset, Tfh cell subset, for its essential roles in germinal center (GC) B development. B cell lymphoma 6 (Bcl6), which is mainly considered as a gene repressor, is the lineage-defining factor of Tfh cells for the evidence that ectopic expression of Bcl6 is sufficient to drive Tfh differentiation while deficiency of Bcl6 results in vanished Tfh differentiation1,2,3. Unlike other CD4+ T helper subsets performing their effector function by migration to the sites of inflammation, Tfh cells provide the B cell help mainly in the B cell follicular zone of spleen and lymph node. Co-stimulatory molecules ICOS and CD40L, play significant roles in the interaction between Tfh and GC B cells. During Tfh differentiation, ICOS transmits necessary signals from cognate B cells and also acts as a receptor receiving migration signals from bystander B cells for B cell zone localization4,5. CD40L is a mediator of signals from Tfh cells for B cells proliferation and survival6. Another factor playing the similar role as CD40L is the cytokine IL21, which is mainly secreted by Tfh cells. IL21 directly regulates GC B cells development and production of high-affinity antibodies, but its role in Tfh differentiation is still controversial7,8. PD-1 and CXCR5, which are now most frequently used in identifying Tfh cells in flow cytometry analysis, also play significant roles in the differentiation and function of this subset. CXCR5 is the receptor of B cell follicular chemokine and mediates the localization of Tfh cells in B cell follicles9. PD-1 is now identified to not only have the follicular guidance function but also transmit critical signals in the process of GC B cells affinity maturation10. Based on these findings, evaluating the expression of these molecules could basically reflect the maturation and function of Tfh cells.
GC is an induced transient microanatomical structure in secondary lymphoid organs and highly dependent on Tfh cells, thus being a perfect readout to evaluate Tfh response. In GC, after receiving signals mediated by cytokines and co-stimulatory molecules, B cells are subject to class switching and somatic hypermutation to generate high-affinity antibodies11. Differential antibody class switching occurs in differential cytokine niche, in which IL4 and IL21 induce IgG1 class switching while IFN&#947; induces IgG2 class switching12. Plasma cells are the producers of secreted antibodies and are terminally differentiated cells. Like Tfh cells, development of B cells in GC is associated with dynamic expression of many significant molecules. Based on the current study, GC B cells can be identified as B220+PNA+Fas+ or B220+GL7+Fas+ cells and plasma cells, compared to their precursors, downregulate expression of B220 and upregulate CD138 expression13. What is more, both of these characteristics can be detected in flow cytometry and immunofluorescence analysis, thus being appropriate evaluation of GC response.
Robust cellular and humoral responses are induced in influenza virus infection, with Tfh and Th1 cells dominating CD4+ T cell response14, which makes it a perfect model for Tfh cells differentiation study. Influenza A/Puerto Rico/8/34 H1N1(PR8), which is a commonly used mouse-adapted strain, is frequently used in this study14,15,16. Here, we describe some basic protocols of Tfh study-relevant assay in influenza virus infection: 1) intranasal inoculation of PR8 virus; 2) antigen-specific Tfh cells, GC B and plasma cells and IL21 detection with flow cytometry; 3) histological visualization of GC; 4) detection of antigen-specific antibody titer in serum with ELISA. These protocols provide the necessary techniques for new researchers in Tfh-associated study.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Immunostaining of Tfh cells, NP-specific Tfh cells and Bcl-6</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>37% formaldehyde</td>
			<td>Sigma</td>
			<td>F1635</td>
			<td></td>
		</tr>
		<tr>
			<td>Anti-CD16/32 mouse</td>
			<td>Thermo Fisher Scientific</td>
			<td>14-0161-86</td>
			<td></td>
		</tr>
		<tr>
			<td>APC-conjugated-IAbNP311-325 MHC class II tetramer</td>
			<td>NIH</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bcl-6 PE</td>
			<td>Biolegend</td>
			<td>358504</td>
			<td>clone:7D1</td>
		</tr>
		<tr>
			<td>Biotin-CXCR5</td>
			<td>Thermo Fisher Scientific</td>
			<td>13-7185-82</td>
			<td>clone: SPRCL5</td>
		</tr>
		<tr>
			<td>CD4 Percp-eFluor 710</td>
			<td>Thermo Fisher Scientific</td>
			<td>46-0041-82</td>
			<td>clone:GK1.5</td>
		</tr>
		<tr>
			<td>CD44 eVolve 605</td>
			<td>Thermo Fisher Scientifi</td>
			<td>83-0441-42</td>
			<td>clone:IM7</td>
		</tr>
		<tr>
			<td>CD44 FITC</td>
			<td>Thermo Fisher Scientifi</td>
			<td>11-0441-82</td>
			<td>clone:IM7</td>
		</tr>
		<tr>
			<td>CD62L FITC</td>
			<td>BD Pharmingen</td>
			<td>553150</td>
			<td>clone:MEL-14</td>
		</tr>
		<tr>
			<td>ICOS BV421</td>
			<td>Biolegend</td>
			<td>564070</td>
			<td>clone:7E.17G9</td>
		</tr>
		<tr>
			<td>PD1 PE/Cy7</td>
			<td>Biolegend</td>
			<td>135216</td>
			<td>clone:29F.1A12</td>
		</tr>
		<tr>
			<td>Streptavidin BV421</td>
			<td>BD Pharmingen</td>
			<td>563259</td>
			<td></td>
		</tr>
		<tr>
			<td>Streptavidin PE</td>
			<td>BD Pharmingen</td>
			<td>554081</td>
			<td></td>
		</tr>
		<tr>
			<td>Intracelluar staining of IL21</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>37% formaldehyde</td>
			<td>Sigma</td>
			<td>F1635</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-human IgG</td>
			<td>Jackson ImmunoResearch Laboratories</td>
			<td>109-605-098</td>
			<td></td>
		</tr>
		<tr>
			<td>Brefeldin A</td>
			<td>Sigma</td>
			<td>B6542</td>
			<td></td>
		</tr>
		<tr>
			<td>human FCc IL-21 receptor</td>
			<td>R&#38;D System</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>ionomycin</td>
			<td>Sigma</td>
			<td>I0634</td>
			<td></td>
		</tr>
		<tr>
			<td>Live/Dead Fixable Aqua Dead Cell staining kit</td>
			<td>Thermo Fisher Scientific</td>
			<td>L34966</td>
			<td></td>
		</tr>
		<tr>
			<td>PMA</td>
			<td>Sigma</td>
			<td>P1585</td>
			<td></td>
		</tr>
		<tr>
			<td>Saponin</td>
			<td>MP</td>
			<td>102855</td>
			<td></td>
		</tr>
		<tr>
			<td>GC B and plasma cells staining</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>B220 APC</td>
			<td>Thermo Fisher Scientific</td>
			<td>17-0452-81</td>
			<td>clone:RA3-6B2</td>
		</tr>
		<tr>
			<td>CD138 PE</td>
			<td>BD Pharmingen</td>
			<td>561070</td>
			<td>clone:281-2</td>
		</tr>
		<tr>
			<td>CD95 (FAS) PE/Cy7</td>
			<td>BD Pharmingen</td>
			<td>557653</td>
			<td>clone:Jo2</td>
		</tr>
		<tr>
			<td>IgD eFluor 450</td>
			<td>Thermo Fisher Scientific</td>
			<td>48-5993-82</td>
			<td>clone:11-26c</td>
		</tr>
		<tr>
			<td>PNA FITC</td>
			<td>Sigma</td>
			<td>L7381</td>
			<td></td>
		</tr>
		<tr>
			<td>Assay of HA-specific antibody titer with ELISA</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>PR8-HA</td>
			<td>Sino Biological</td>
			<td>11684-V08H</td>
			<td></td>
		</tr>
		<tr>
			<td>BSA</td>
			<td>SSBC</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti mouse Ig (SBA Clonotyping System-HRP)</td>
			<td>SouthernBiotech</td>
			<td>5300-05</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti mouse IgM (SBA Clonotyping System-HRP)</td>
			<td>SouthernBiotech</td>
			<td>5300-05</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti mouse IgG1 (SBA Clonotyping System-HRP)</td>
			<td>SouthernBiotech</td>
			<td>5300-05</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti mouse IgG2b (SBA Clonotyping System-HRP)</td>
			<td>SouthernBiotech</td>
			<td>5300-05</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti mouse IgG2c (SBA Clonotyping System-HRP)</td>
			<td>SouthernBiotech</td>
			<td>5300-05</td>
			<td></td>
		</tr>
		<tr>
			<td>TMB Substrate Reagent Set</td>
			<td>BD Pharmingen</td>
			<td>555214</td>
			<td></td>
		</tr>
		<tr>
			<td>Histology</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa Fluor 555-Goat-anti rat IgG</td>
			<td>Life Technology</td>
			<td>A21434</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse IgD</td>
			<td>Biolegend</td>
			<td>405702</td>
			<td></td>
		</tr>
		<tr>
			<td>biotinylated PNA</td>
			<td>Vector laboratories</td>
			<td>B-1075</td>
			<td></td>
		</tr>
		<tr>
			<td>dilute Alexa Fluor 488-streptavidin</td>
			<td>Life Technology</td>
			<td>S11223</td>
			<td></td>
		</tr>
		<tr>
			<td>normal goat serum</td>
			<td>SouthernBiotech</td>
			<td>0060-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Pro-long gold antifade reagent</td>
			<td>Thermo Fisher Scientific</td>
			<td>P3630</td>
			<td></td>
		</tr>
		<tr>
			<td>STREPTAVIDIN/BIOTIN blocking kit</td>
			<td>Vector laboratories</td>
			<td>SP-2002</td>
			<td></td>
		</tr>
	</tbody>
</table>

evaluation of t follicular helper cells and germinal center response during influenza a virus infection in mice

T Follicular Helper (Tfh) cells are an independent CD4+&#160;T cell subset specialized in providing help for germinal center (GC) development and generation of high-affinity antibodies. In influenza virus infection, robust Tfh and GC B cell responses are induced to facilitate effective virus eradication, which confers a qualified mouse model for Tfh-associated study. In this paper, we described protocols in detection of basic Tfh-associated immune response during influenza virus infection in mice. These protocols include: intranasal inoculation of influenza virus; flow cytometry staining and analysis of polyclonal and antigen-specific Tfh cells, GC B cells and plasma cells; immunofluorescence detection of GCs; enzyme-linked immunosorbent assay (ELISA) of influenza virus-specific antibody in serum. These assays basically quantify the differentiation and function of Tfh cells in influenza virus infection, thus providing help for studies in elucidating differentiation mechanism and manipulation strategy.

Characterization of mouse morbidity in influenza virus infection 
After influenza virus infection, mice are less active and anorexic due to illness, which is reflected by severe weight loss, a commonly used symptom to monitor the mouse morbidity19. As shown in Figure 1a, PR8 virus-infected mice started to lose weight on day 6, reached the highest loss level on day 8 and returned to the initial level on day 10. As expected, weight...

Watch this Scientific Journal Video about Evaluation of T Follicular Helper Cells and Germinal Center Response During Influenza A Virus Infection in Mice at JoVE.com

Evaluation of T Follicular Helper Cells and Germinal Center Response During Influenza A Virus Infection in Mice

This paper describes protocols of evaluating Tfh and GC B response in mouse model of influenza virus infection.

T Follicular Helper (Tfh) cells are an independent CD4+&#160;T cell subset specialized in providing help for germinal center (GC) development and ...

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Immunology and Infection

Using Bioluminescent Imaging to Investigate Synergism Between Streptococcus pneumoniae and Influenza A Virus in Infant Mice

Using Bioluminescent Imaging to Investigate Synergism Between Streptococcus pneumoniae and Influenza A Virus in Infant Mice

During the 1918 influenza virus pandemic, which killed approximately 50 million people worldwide, the majority of fatalities were not the result of ...

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

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 ...

Influenza Virus Propagation in Embryonated Chicken Eggs

Influenza infection is associated with about 36,000 deaths and more than 200,000 hospitalizations every year in the United States. The continuous ...

Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein

Studying the interaction between proteins is key in understanding their function(s). A very powerful method that is frequently used to study interactions ...

Measuring Attachment and Internalization of Influenza A Virus in A549 Cells by Flow Cytometry

Attachment to target cells followed by internalization are the very first steps of the life cycle of influenza A virus (IAV). We provide here a detailed ...

Neutrophil Isolation and Analysis to Determine their Role in Lymphoma Cell Sensitivity to Therapeutic Agents

Neutrophils are the most abundant (40% to 75%) type of white blood cells and among the first inflammatory cells to migrate towards the site of ...

In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation

In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation

Acid-triggered molecular processes closely control cell entry of many viruses that enter through the endocytic system. In the case of influenza A virus ...

Influenza A Virus Studies in a Mouse Model of Infection

Influenza viruses cause over 500,000 deaths worldwide1 and are associated with an annual cost of 12 - 14 billion USD in the United States alone ...

Induction of Paralysis and Visual System Injury in Mice by T Cells Specific for Neuromyelitis Optica Autoantigen Aquaporin-4

While it is recognized that aquaporin-4 (AQP4)-specific T cells and antibodies participate in the pathogenesis of neuromyelitis optica (NMO), a human ...

Evaluation of Extracellular Vesicle Function During Malaria Infection

Malaria is a life-threatening disease caused by Plasmodium parasites, with P. falciparum being the most prevalent on the African continent and responsible ...