We are indebted to our technical assistants:&#160;U. Br&#246;der and H. Shkarlet, who helped us during experimental procedures. This work was partly funded by EU grants (UniVax, contract No. 601738, and TRANSVAC2, contract No. 730964), and a Helmholtz Association grant (HAI-IDR). The funding sources did not influence the research design, generation of the manuscript or decision to submit it for publication.

All mice used in this study were from the C57BL/6 background. All the animals were kept under pathogen-free conditions. All experiments were performed according to the normative of the German animal protection law (TierSchG BGBl. I S 1105; 25.05.1998) and were approved by the Lower Saxony Committee on the Ethics of Animal Experiments and the state office (Lower Saxony State Office of Consumer Protection and Food Safety), under permit number 33.4-42502-04-13/1281 and 162280.
1. CFSE Staining of O...

<ol>
	<li>Krishna, S., Anderson, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=T-Cell+Epitope+Discovery+for+Therapeutic+Cancer+Vaccines.">T-Cell Epitope Discovery for Therapeutic Cancer Vaccines.</a> Methods Mol Biol. 1403, 779-796 (2016).</li><li>Pinchuk, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+CD8++T+cell+heptaepitope+minigene+vaccine+induces+protective+immunity+against+Chlamydia+pneumoniae.">A CD8+ T cell heptaepitope minigene vaccine induces protective immunity against Chlamydia pneumoniae.</a> Journal of immunology. 174, 5729-5739 (2005).</li><li>Zhang, J., Silvestri, N., Whitton, J. L., Hassett, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neonates+mount+robust+and+protective+adult-like+CD8(+)-T-cell+responses+to+DNA+vaccines.">Neonates mount robust and protective adult-like CD8(+)-T-cell responses to DNA vaccines.</a> Journal of virology. 76, 11911-11919 (2002).</li><li>Marchant, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mature+CD8(+)+T+lymphocyte+response+to+viral+infection+during+fetal+life.">Mature CD8(+) T lymphocyte response to viral infection during fetal life.</a> J Clin Invest. 111, 1747-1755 (2003).</li><li>Simmons, C. P., 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=Mucosal+delivery+of+a+respiratory+syncytial+virus+CTL+peptide+with+enterotoxin-based+adjuvants+elicits+protective,+immunopathogenic,+and+immunoregulatory+antiviral+CD8++T+cell+responses.">Mucosal delivery of a respiratory syncytial virus CTL peptide with enterotoxin-based adjuvants elicits protective, immunopathogenic, and immunoregulatory antiviral CD8+ T cell responses.</a> Journal of immunology. 166, 1106-1113 (2001).</li><li>Fulginiti, V. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Respiratory+Virus+Immunizationa+Field+Trial+Of+Two+Inactivated+Respiratory+Virus+Vaccines;+An+Aqueous+Trivalent+Paratnfluenza+Virus+Vaccine+And+An+Alum-Precipitated+Respiratory+Syncytial+Virus+Vaccine1.">Respiratory Virus Immunizationa Field Trial Of Two Inactivated Respiratory Virus Vaccines; An Aqueous Trivalent Paratnfluenza Virus Vaccine And An Alum-Precipitated Respiratory Syncytial Virus Vaccine1.</a> American journal of epidemiology. 89, 435-448 (1969).</li><li>Olson, M. R., Varga, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD8+T+cells+inhibit+respiratory+syncytial+virus+(RSV)+vaccine-enhanced+disease.">CD8 T cells inhibit respiratory syncytial virus (RSV) vaccine-enhanced disease.</a> Journal of immunology. 179, 5415-5424 (2007).</li><li>Lirussi, D., 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=Type+I+IFN+and+not+TNF,+is+Essential+for+Cyclic+Di-nucleotide-elicited+CTL+by+a+Cytosolic+Cross-presentation+Pathway.">Type I IFN and not TNF, is Essential for Cyclic Di-nucleotide-elicited CTL by a Cytosolic Cross-presentation Pathway.</a> EBioMedicine. 22, 100-111 (2017).</li><li>Ebensen, T., 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=Bis-(3',5')-cyclic+dimeric+adenosine+monophosphate:+strong+Th1/Th2/Th17+promoting+mucosal+adjuvant.">Bis-(3',5')-cyclic dimeric adenosine monophosphate: strong Th1/Th2/Th17 promoting mucosal adjuvant.</a> Vaccine. 29, 5210-5220 (2011).</li><li>Hogquist, K. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=T+cell+receptor+antagonist+peptides+induce+positive+selection.">T cell receptor antagonist peptides induce positive selection.</a> Cell. 76, 17-27 (1994).</li><li>Clarke, S. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+the+ovalbumin-specific+TCR+transgenic+line+OT-I:+MHC+elements+for+positive+and+negative+selection.">Characterization of the ovalbumin-specific TCR transgenic line OT-I: MHC elements for positive and negative selection.</a> Immunology and cell biology. 78, 110-117 (2000).</li><li>Topham, D. J., Castrucci, M. R., Wingo, F. S., Belz, G. T., Doherty, P. 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+role+of+antigen+in+the+localization+of+naive,+acutely+activated,+and+memory+CD8(+)+T+cells+to+the+lung+during+influenza+pneumonia.">The role of antigen in the localization of naive, acutely activated, and memory CD8(+) T cells to the lung during influenza pneumonia.</a> Journal of immunology. 167, 6983-6990 (2001).</li><li>Le Bon, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cross-priming+of+CD8++T+cells+stimulated+by+virus-induced+type+I+interferon.">Cross-priming of CD8+ T cells stimulated by virus-induced type I interferon.</a> Nature immunology. 4, 1009-1015 (2003).</li><li>Otto, K., Bullock, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Laboratory Mouse. , 555-569 (2004).</li><li>Lim, J. F., Berger, H., Su, I. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+Activation+of+Murine+Lymphocytes.">Isolation and Activation of Murine Lymphocytes.</a> Journal of visualized experiments: JoVE. , (2016).</li><li>Shimizu, S., Bullock, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Laboratory Mouse. , 527-542 (2004).</li><li>Breton, G., Lee, J., Liu, K., Nussenzweig, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Defining+human+dendritic+cell+progenitors+by+multiparametric+flow+cytometry.">Defining human dendritic cell progenitors by multiparametric flow cytometry.</a> Nature protocols. 10, 1407-1422 (2015).</li><li>Kaminski, D. A., Wei, C., Rosenberg, A. F., Lee, F. E. -. H., Sanz, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiparameter+Flow+Cytometry+and+Bioanalytics+for+B+Cell+Profiling+in+Systemic+Lupus+Erythematosus.">Multiparameter Flow Cytometry and Bioanalytics for B Cell Profiling in Systemic Lupus Erythematosus.</a> Methods in molecular biology. 900, 109-134 (2012).</li><li>Bayer, J., Grunwald, D., Lambert, C., Mayol, J. F., Maynadie, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thematic+workshop+on+fluorescence+compensation+settings+in+multicolor+flow+cytometry.">Thematic workshop on fluorescence compensation settings in multicolor flow cytometry.</a> Cytometry. Part B, Clinical cytometry. 72, 8-13 (2007).</li><li>Newrzela, 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=T-cell+receptor+diversity+prevents+T-cell+lymphoma+development.">T-cell receptor diversity prevents T-cell lymphoma development.</a> Leukemia. 26, 2499-2507 (2012).</li><li>Iwasaki, N., 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=Allergen+endotoxins+induce+T-cell-dependent+and+non-IgE-mediated+nasal+hypersensitivity+in+mice.">Allergen endotoxins induce T-cell-dependent and non-IgE-mediated nasal hypersensitivity in mice.</a> J Allergy Clin Immunol. 139, 258-268 (2017).</li><li>Tsuchiya, K., Siddiqui, S., Risse, P. A., Hirota, N., Martin, J. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+presence+of+LPS+in+OVA+inhalations+affects+airway+inflammation+and+AHR+but+not+remodeling+in+a+rodent+model+of+asthma.+American+journal+of+physiology.">The presence of LPS in OVA inhalations affects airway inflammation and AHR but not remodeling in a rodent model of asthma. American journal of physiology.</a> Lung cellular and molecular physiology. , L54-L63 (2012).</li><li>Burgdorf, S., Scholz, C., Kautz, A., Tampe, R., Kurts, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+and+mechanistic+separation+of+cross-presentation+and+endogenous+antigen+presentation.">Spatial and mechanistic separation of cross-presentation and endogenous antigen presentation.</a> Nature. 9, 558-566 (2008).</li><li>Last'ovicka, J., Budinsky, V., Spisek, R., Bartunkova, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+lymphocyte+proliferation:+CFSE+kills+dividing+cells+and+modulates+expression+of+activation+markers.">Assessment of lymphocyte proliferation: CFSE kills dividing cells and modulates expression of activation markers.</a> Cellular immunology. , 79-85 (2009).</li><li>Oelke, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+characterization+of+CD8(+)+antigen-specific+cytotoxic+T+lymphocytes+after+enrichment+based+on+cytokine+secretion:+comparison+with+the+MHC-tetramer+technology.">Functional characterization of CD8(+) antigen-specific cytotoxic T lymphocytes after enrichment based on cytokine secretion: comparison with the MHC-tetramer technology.</a> Scand J Immunol. 52, 544-549 (2000).</li><li>Wang, W., Golding, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cytotoxic+T+lymphocyte+response+against+a+protein+antigen+does+not+decrease+the+antibody+response+to+that+antigen+although+antigen-pulsed+B+cells+can+be+targets.">The cytotoxic T lymphocyte response against a protein antigen does not decrease the antibody response to that antigen although antigen-pulsed B cells can be targets.</a> Immunology letters. 100, 195-201 (2005).</li><li>O'Sullivan, D., 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=Memory+CD8(+)+T+cells+use+cell-intrinsic+lipolysis+to+support+the+metabolic+programming+necessary+for+development.">Memory CD8(+) T cells use cell-intrinsic lipolysis to support the metabolic programming necessary for development.</a> Immunity. 41, 75-88 (2014).</li><li>Xu, H. 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=Type+I+interferon+protects+antiviral+CD8++T+cells+from+NK+cell+cytotoxicity.">Type I interferon protects antiviral CD8+ T cells from NK cell cytotoxicity.</a> Immunity. 40, 949-960 (2014).</li><li>Volk, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+three+humanized+mouse+models+for+adoptive+T+cell+transfer.">Comparison of three humanized mouse models for adoptive T cell transfer.</a> The journal of gene medicine. 14, 540-548 (2012).</li><li>Safinia, N., 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=Humanized+Mice+as+Preclinical+Models+in+Transplantation.">Humanized Mice as Preclinical Models in Transplantation.</a> Methods Mol Biol. 1371, 177-196 (2016).</li><li>Grover, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Humanized+NOG+mice+as+a+model+for+tuberculosis+vaccine-induced+immunity:+a+comparative+analysis+with+the+mouse+and+guinea+pig+models+of+tuberculosis.">Humanized NOG mice as a model for tuberculosis vaccine-induced immunity: a comparative analysis with the mouse and guinea pig models of tuberculosis.</a> Immunology. 152, 150-162 (2017).</li></ol>

The authors have nothing to disclose.

Modern vaccines are ideally composedof purified antigen and adjuvants, with the possible addition of a delivery system like liposomes, virus-like particles, nanoparticles or live vectors. A key aspect when designing a vaccine is to choose the right adjuvant according to the clinical needs. Part of the scope could involve favoring a humoral vs. cellular immune response (or both), the election of a local vs. a systemic immune response (or both), and the kind of memory that the vaccine must generate in the target population...

Cytotoxic T lymphocytes (CTL) inducing vaccines are key therapeutic interventions that have been developed to fight certain types of cancer1. CTL are also important for prophylactic vaccines against intracellular pathogens2. Moreover, CTL are one of the few immune defense mechanisms functionally active in risk populations such as neonates3,4 whom also depend on CTL to combat early life infections5. In this regard, vaccines against Respiratory Syncytial Virus (RSV) that were developed with an adjuvant that does not elicit CTL responses (alum) resulted in a complete failure of the vaccine leading to serious complications upon infections in infants6. These negative effects of vaccination can be reversed by a CD8+ T cell response7. We have previously demonstrated that the main cytokines (type I interferons) elicited by some stimulator of interferon genes (STING) agonists are essential for the CTL responses generated by these adjuvants8, in part by measuring the proliferation of OT-I T cells after vaccination and using these results as a measure of CTL inducing capabilities observed in extended vaccination schedules9. The measurement of the proliferation of OT-I CD8+ T cells in a wild type (WT) C57BL/6 recipient mouse by carboxyfluorescein succinimidyl ester (CFSE) dye dilution is a robust estimation of the capability of the adjuvant of a vaccine to generate cross-priming of SIINFEKL, (the immuno-dominant peptide of ovalbumin, OVA). Variations of this technique are widely used for the assessment of the proliferation of OT-I CD8+ and OT-II CD4+ T cells. For example, it has been used in the absence of selected cytokines (KO mice) or to measure vaccine efficacy after antigen recall in WT animals. We devised a short protocol (4 days experiment) in which after passive transfer of CFSE-stained OT-I CD8+ T cells, a subcutaneous (s.c.) immunization consisting of one dose of 50 &#181;g of endotoxin-free OVA supplemented with test adjuvants is administered (Figure 1). The follow up of the results 48 h after vaccination provides a reliable proof of the capacity of the adjuvant to generate CTL responses. By this strategy, it is possible to assess the potency of the local immune response in the draining lymph node after immunization as well as the extent of the response by measuring the CTL activity in the spleen (or distant lymph nodes).

<table>
	<tbody>
		<tr>
			<td>BD LSR Fortessa Cell Analyzer</td>
			<td>BD</td>
			<td>Special Order</td>
			<td>Flow Cytometer</td>
		</tr>
		<tr>
			<td>CFSE</td>
			<td>Molecular Probes</td>
			<td>C34554</td>
			<td>Proliferation Dye</td>
		</tr>
		<tr>
			<td>MojoSort Mouse CD8 T Cell Isolation Kit</td>
			<td>Biolegend</td>
			<td>480007</td>
			<td>Magnetic Isolation Beads and antibodies for negative selection of untouched CD8 T cells.</td>
		</tr>
		<tr>
			<td>LIVE/DEAD Fixable Blue Dead Cell Stain Kit, for UV excitation</td>
			<td>Molecular Probes</td>
			<td>L23105</td>
			<td>Dead Cell Marker</td>
		</tr>
		<tr>
			<td>CD90.1 (Thy-1.1) Monoclonal Antibody (HIS51), PE-Cyanine7</td>
			<td>eBioscience</td>
			<td>25-0900-82</td>
			<td>antibody</td>
		</tr>
		<tr>
			<td>APC anti-mouse CD8a Antibody</td>
			<td>BioLegend</td>
			<td>100712</td>
			<td>antibody</td>
		</tr>
		<tr>
			<td>BV421 Rat Anti-Mouse CD4</td>
			<td>BD</td>
			<td>740007</td>
			<td>antibody</td>
		</tr>
		<tr>
			<td>Z2 coulter Particle count and Size Analyzer</td>
			<td>Beckman Coulter</td>
			<td>9914591DA</td>
			<td>Cell counter. Z2 Automated particle/cell counter</td>
		</tr>
		<tr>
			<td>EndoGrade Ovalbumin (10 mg)</td>
			<td>Hyglos(Germany)</td>
			<td>321000</td>
			<td>Ovalbumin endotoxin free tested.</td>
		</tr>
		<tr>
			<td>Cell Strainer 100&#181;m nylon</td>
			<td>Corning</td>
			<td>352360</td>
			<td>Cell strainer (100 &#181;m pore mesh cups).</td>
		</tr>
		<tr>
			<td>Sample Vials</td>
			<td>Beckman Coulter</td>
			<td>899366014</td>
			<td>Sample vials for Z2 automated counter</td>
		</tr>
		<tr>
			<td>C57BL/6 mice (CD90.2)</td>
			<td>Harlan (Rossdorf, Germany)</td>
			<td></td>
			<td>Company is now Envigo</td>
		</tr>
		<tr>
			<td>OT-I (C57BL/6 background, CD90.1)</td>
			<td>Harlan (Rossdorf, Germany)</td>
			<td></td>
			<td>Inbreed at our animal facility. Company from where adquired is now Envigo</td>
		</tr>
		<tr>
			<td>FACS tubes</td>
			<td>Fischer (Corning)</td>
			<td>14-959-5</td>
			<td>Corning Falcon Round-Bottom Polystyrene Tubes</td>
		</tr>
		<tr>
			<td>Falcon 15 mL tubes</td>
			<td>Fischer (Corning)</td>
			<td>05-527-90</td>
			<td>Falcon 15mL Conical Centrifuge Tubes</td>
		</tr>
		<tr>
			<td>PBS (500 mL)</td>
			<td>Fischer (Gibco)</td>
			<td>20-012-027</td>
			<td>Gibco PBS (Phosphate Buffered Saline), pH 7.2</td>
		</tr>
		<tr>
			<td>Red lamp (heating lamp)</td>
			<td>Dirk Rossmann GmbH (Germany)</td>
			<td>405096</td>
			<td>Heating infrred lamp (100 wats)</td>
		</tr>
		<tr>
			<td>IsoFlo (Isoflurane)</td>
			<td>Abbott Laboratories (USA)</td>
			<td>5260.04-05.</td>
			<td>Isoflurane anesthesic (250 mL flask).</td>
		</tr>
		<tr>
			<td>Tabletop Anesthesia Machine/Mobile Anesthesia Machine with CO2 Absorber</td>
			<td>Parkland Scientific</td>
			<td>V3000PK</td>
			<td>Isoflurane anesthesia machine.</td>
		</tr>
		<tr>
			<td>RPMI 1640 medium</td>
			<td>Gibco (distributed by ThermoFischer)</td>
			<td>11-875-093</td>
			<td>Base medium with Glutamine (500 mL)</td>
		</tr>
		<tr>
			<td>Pen-Strept antibiotic solution (Gibco)</td>
			<td>Gibco (distributed by ThermoFischer)</td>
			<td>15-140-148</td>
			<td>Gibco Penicillin-Streptomycin (10,000 U/mL)</td>
		</tr>
		<tr>
			<td>Fetal Bobine Serum (Gibco)</td>
			<td>Gibco (distributed by ThermoFischer)</td>
			<td>10082147</td>
			<td>Fetal Bovine Serum, certified, heat inactivated, US origin</td>
		</tr>
		<tr>
			<td>ACK Lysing Buffer (100 ml)</td>
			<td>Gibco (distributed by ThermoFischer)</td>
			<td>A1049201</td>
			<td>Amonium Chloride Potasium (ACK) Whole Blood Lysis Buffer, suitable for erytrocyte lysis in spleen suspensions also</td>
		</tr>
		<tr>
			<td>Plastic Petri Dishes</td>
			<td>Nunc (distributed by ThermoFischer)</td>
			<td>150340</td>
			<td>60 x 15mm Plastic Petri Dish, Non-treated</td>
		</tr>
		<tr>
			<td>Cell Clump Filter</td>
			<td>CellTrics (Sysmex)</td>
			<td>04-004-2317</td>
			<td>CellTrics&#174; 50 &#956;m, sterile</td>
		</tr>
	</tbody>
</table>

rapid in vivo assessment of adjuvant's cytotoxic t lymphocytes generation capabilities for vaccine development

The assessment of modern sub-unit vaccines reveals that the generation of neutralizing antibodies is important but not sufficient for adjuvant selection. Therefore, adjuvants with both humoral and cellular immuno-stimulatory capabilities that are able to promote cytotoxic T lymphocytes (CTL) responses are urgently needed. Thus, faithful monitoring of adjuvant candidates that induce cross-priming and subsequently enhance CTL generation represents a crucial step in vaccine development. In here we present an application for a method that uses SIINFEKL-specific (OT-I) T cells to monitor the cross-presentation of the model antigen ovalbumin (OVA) in vivo in the presence of different adjuvant candidates. This method represents a rapid test to select adjuvants with the best cross-priming capabilities. The proliferation of CD8+ T cells is the most valuable indication of cross-priming and it is also regarded as a correlate of adjuvant-induced cross-presentation. This feature can be evaluated in different immune organs like lymph nodes and spleen. The extent of the CTL generation can also be monitored, thereby giving insights on the nature of a local (draining lymph node mainly) or a systemic response (distant lymph nodes and/or spleen). This technique further allows multiple modifications for testing drugs that can inhibit specific cross-presentation pathways and also offers the possibility to be used in different strains of conventional and genetically modified mice. In summary, the application that we present here will be useful for vaccine laboratories in industry or academia that develop or modify chemical adjuvants for vaccine research and development.

In order to test the treatments using a different combination of adjuvants (ADJ1 and ADJ2), we have assessed the CTL generation capacity by measuring the proliferation of adoptively transferred OT-I CD8+ T cells by flow cytometry (Figure 2). For this, we previously stained isolated cells from the draining lymph nodes and spleen (Table 1). By measuring the proliferation of CD8+ T cells in lymph nodes and spleen, we were a...

Watch this Scientific Journal Video about Rapid In Vivo Assessment of Adjuvant's Cytotoxic T Lymphocytes Generation Capabilities for Vaccine Development at JoVE.com

Rapid In Vivo Assessment of Adjuvant&#039;s Cytotoxic T Lymphocytes Generation Capabilities for Vaccine Development

We present here an application for a standard immunological technique (CFSE stained OT-I proliferation) intended to rapidly monitor adjuvant-mediated cytotoxic T lymphocyte (CTL) generation in vivo. This fast estimation of CTL capacities is useful for the development of prophylactic vaccines against intracellular pathogens as well as therapeutic cancer vaccines.

Rapid In Vivo Assessment of Adjuvant's Cytotoxic T Lymphocytes Generation Capabilities for Vaccine Development

The assessment of modern sub-unit vaccines reveals that the generation of neutralizing antibodies is important but not sufficient for adjuvant selection. ...

The overall goal of this experiment is to determine the ability of adjuvants of interest to generate cytotoxic T lymphocytes by monitoring adoptively transferred CFSE stained OT1 CD8 positive T cell proliferation in the draining lymph nodes and spleens of immunized recipient animals. This method can help to answer key questions in the vaccinology field like the potency of an adjuvant to generate a cytotoxicity cell response. The main advantage of this technique is that you can determine not only the CTL capacity of an adjuvant, but also if this is local or systemic and you can do it only in four days.Demonstrating the procedure will be a technician in our lab, Elena Reinhard. To isolate thigh 1.1 positive CD8 positive T cells from OT1 mice, first harvest the spleen and inguinal, axillary, and cervical lymph nodes according to standard protocols placing all of the organs into a 100 micrometer pore mesh strainer in a 60 millimeter Petri dish containing three to five milliliters of complete medium on ice per mouse as they are collected. Do not harvest in large OT1 spleens or lymph nodes because the T cells from these lymph tissues may be leukemic and will proliferate even without stimulation confounding the assay results.When all of the organs have been retrieved from each donor animal, use a syringe plunger to mash the samples through the mesh filter and transfer the resulting single suspensions into one 15 milliliter conical tube per mouse. Pellet the cells by centrifugation, followed by a centrifugation wash in 10 milliliters of cold PBS. Lyse the red blood cell pellet in one milliliter of ammonium chloride buffer per tube on ice.After 90 seconds, wash the cells in another 10 milliliters of PBS and resuspend the cells in one milliliter of PBS plus 5%FBS per tube. Then use a negative selective kit to isolate the CD8 positive T cells according to standard magnetic bead isolation protocols and count the number of magnetic bead sorted CD8 positive T cells. Next, dilute the T cells to a one to five by 10 to the seventh cells per milliliter of PBS concentration in individual 15 milliliter conical tubes and stain each cell sample with five micromolar CFSE for seven minutes at 37 degrees Celsius and protected from light.At the end of incubation, quench the staining reaction with an equal volume of FBS and return the cells to a 37 degree Celsius incubator for an additional seven minutes. At the end of the second incubation, wash the cells two times in 10 milliliters of PBS per wash and resuspend the cells in three to five by 10 to the seventh cells per milliliter volumes of PBS. For adoptive transfer of the CFSE labeled OT1 T cells, load the cells into one one milliliter syringe equipped with a 25 gauge needle per experimental cell sample and immobilize the first recipient mouse in a restrainer.Then when the tail veins have vasodilated, deliver 100 microliters of cells via the lateral or dorsal tail vein. For immunization of the adoptively transferred animals, shave the fur over the gluteus superficialis of the OT1 T cell transplanted mouse and use a 25 gauge needle to subcutaneously inject 50 microliters of endotoxin-free OVA into the shaved area. It's important to use endotoxin-free OVA because traces of endotoxin in OVA can lead you to false results.Forty-eight hours after the immunization, harvest the inguinal lymph nodes and spleens from each recipient animal according to standard protocols and generate individual single cell suspensions for each lymph node and spleen sample as just demonstrated. Collect the cells by centrifugation and resuspend the pellets in 100 microliters of PBS per sample. To stain the samples for flow cytometric analysis, incubate the cells with 100 microliters of fluorophore conjugated primary antibody master mix cocktail for 30 minutes at four degrees Celsius.At the end of the incubation, wash the cells two times in 10 milliliters of PBS and resuspend the samples in 0.5 to one milliliter of PBS per tube. Filter the cells through 70 to 100 micrometer strainers into five millimeter flow cytometry analysis tubes and acquire the single staining compensation controls as well as the samples in the flow cytometer. To gate the samples, open a forward scatter height versus forward scatter area plot and a side scatter wide versus side scatter area plot and gate to exclude the doublets.Generate a FITC versus auto fluorescence plot in order to discriminate the population of true CSFE stained cells from the high auto fluorescent cells. Gate these OT1 CSFE stained cells as the populations that extend mostly on the FITC axis. To distinguish cells derived from donor versus recipient animals, gate the thigh 1.1 plus CD90 0.1 plus CD8 plus T cells and re-gate the CD8 plus population to exclude the CD4 plus T cells.Then display this proliferated CD8 T cell population in a histogram according to their CSFE expression and gate the proliferated populations from a 10 to the second intensity up to the undivided control population intensity. Acquire at least 5, 000 events for the compensation controls and 10, 000 events for each sample at a low or medium flow analysis rate. In this experiment, two groups of mice were vaccinated with one of two different adjuvants.Mice that were injected with OVA plus the second adjuvant exhibited a higher cytotoxic T cell generation capacity locally in the draining lymph nodes compared to mice injected with the first adjuvant plus OVA, OVA alone, or the PBS control vaccine. In contrast, in mice injected with the second adjuvant plus OVA did not generate a cytotoxic T cell response in a systemic compartment whereas CD8 positive T cells isolated from the spleens of adjuvant one plus OVA mice demonstrated higher levels of proliferation than splenic CD8 positive T cells isolated from OVA alone, PBS control, and adjuvant two plus OVA vaccinated animals. Once mastered, this technique will allow you to determine the CTL capacity of an adjuvant molecule by using OVA antigen in just four days of work.After performing this technique, you will be able to further apply all other techniques to the T cells isolated and then to phenotype the cytokine profile or the metabolic profile of the CTL response of your adjuvant.

rapid-vivo-assessment-adjuvant-s-cytotoxic-t-lymphocytes-generation

Research

JoVE Journal

Medicine

8.5K Görüntüleme.  Helmholtz Centre for Infection Research. The overall goal of this experiment is to determine the ability of adjuvants of interest to generate cytotoxic T lymphocytes by monitoring adoptively transferred CFSE stained OT1 CD8 positive T cell proliferation in the draining lymph nodes and spleens of immunized recipient animals. This method can help to answer key questions in the vaccinology field like the potency of an adjuvant to generate a cytotoxicity cell response. The main advantage of this technique is that you can determine not o...