This work was supported in part by National Institutes of Health grants 5T32AI7493-20 and&#160;5R01AI089337-03. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

The University of Alabama at Birmingham Institutional Animal Use and Care Committee approved the use of mice as described herein under the approved protocol number 101109272.
1. Genetic Construction of a Modified Plasmid pAd5/H5-HVR1-KWAS-HVR5-His 6 with the Antigen Capsid-Incorporation Strategy
<ol>
	<li>Construction of the shuttle plasmid HVR1-KWAS-HVR5-His6/pH5S
	<ol>
		<li>Order a plasmid containing the synthesized DNA sequence HVR1-KWAS between the restriction enzyme sites AgeI to AccI of hexon5 gene.</li>
		<li>Digest 6 &#181;g of the synthesized fragment (HVR1-KWAS) with the enzymes AgeI (6 units) and AccI (6 units) for 3 hrs at 37 &#176;C. Resolve the digested fragment in a 2% agarose gel by electrophoresis, and purify the fragment with a DNA gel extraction kit according to the manufacturer&#8217;s protocol.</li>
		<li>Based on the molar ratio of insert to vector at 3 : 1, use T4 DNA ligase and ligase buffer to ligate 12 ng of the fragment (HVR1-KWAS) into 100 ng of a previously constructed shuttle plasmid HVR5-His6/pH5S17 in a 10 &#181;l volume at RT for 2 hr, via the sites of AgeI and AccI.</li>
		<li>Transform 1 &#181;l out of 10 &#181;l of the ligation product into 50 &#181;l of electrocompetent DH5&#945; cells in an electroporator (at 1800 V). Add 950 &#181;l of SOC medium to the transformed DH5&#945; cells and incubate the mixture for 1 hr at 37 &#176;C, with 300 rpm. Spread 100-200 &#181;l of the 1 ml mixture on the Luria-Bertani (LB) agar containing kanamycin and incubate O/N at 37 &#176;C.
		<ol>
			<li>To screen ~ 10 colonies by PCR targeting the fragment HVR1-KWAS, mix the forward primer (TATGTGTGTCATGTATGCGT), reverse primer (GGAGGCCCACTTGTCCAGCTC) and a single DH5&#945; colony into a PCR master mix solution (according to manufacturer&#8217;s protocol). Run samples on a thermocycler by referring to the manual provided with the PCR master mix solution.</li>
			<li>Use the forward primer (TATGTGTGTCATGTATGCGT) to sequence the fragment HVR1-KWAS in the clones screened in the section 1.1.4.1.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Construction of the plasmid pAd5/H5-HVR1-KWAS-HVR5-His6
	<ol>
		<li>Digest 6 &#181;g of HVR1-KWAS-HVR5-His6/pH5S with enzymes EcoRI (6 units) and PmeI (6 units) for 3 hrs at 37 &#176;C, and purify the fragment containing homologous recombination arms and the dual modified hexon5 gene, as stated in step 1.1.2. Linearize the backbone plasmid pAd5/&#8710;H5 (GL)16 with SwaI.</li>
		<li>Co-transform 100 ng of the target fragment from the shuttle plasmid and 100 ng of the linearized pAd5/&#8710;H5 (GL) backbone into 50 &#181;l of electrocompetent BJ5183 cells for the homologous recombination in an electroporator (at 1800 V). Add 950 &#181;l of SOC medium to the transformed cells and incubate the mixture for 1 hr at 37 &#176;C, 300 rpm. Spread 100 - 200 &#181;l of the 1 ml mixture on the LB agar containing kanamycin (final 50 &#181;g/ml) for O/N incubation at 37 &#176;C.
		<ol>
			<li>Pick ~10 tiny colonies into 3 ml liquid LB containing kanamycin (final 50 &#181;g/ml) for O/N incubation at a shaker (250 rpm, 37&#176;C). Extract plasmids from the culture. Use PCR analysis to screen the 10 colonies by targeting the fragment HVR1-KWAS, as illustrated in step 1.1.4.1.</li>
			<li>To screen the same colonies by PCR analysis targeting the pIX fragment of the backbone genome, mix the forward primer (AGCTGTTGGATCTGCGCCAGCAGGTT), reverse primer (CCAAACAGAGTCTGGTTTTTTATTTAT) and a single BJ5183 colony into a PCR master mix solution (according to manufacturer&#8217;s protocol). Run samples on a thermocycler by referring to the manual provided with the PCR master mix solution.</li>
			<li>Designate the PCR double-positive colonies as pAd5/H5-HVR1-KWAS-HVR5-His6.</li>
		</ol>
		</li>
		<li>Transform 100 ng of the plasmid pAd5/H5-HVR1-KWAS-HVR5-His6 into DH5&#945; cells as illustrated in step 1.1.4.
		<ol>
			<li>Use PCR analysis to screen ~ 10 colonies by targeting the fragment HVR1-KWAS, as illustrated in step 1.1.4.1.</li>
			<li>Use PCR analysis to screen the same colonies by targeting the pIX fragment of the backbone genome, as illustrated in step 1.2.2.2.</li>
			<li>Use the forward primer (TATGTGTGTCATGTATGCGT) to sequence the fragment HVR1-KWAS in pAd5/H5-HVR1-KWAS-HVR5-His6.</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
2. Preparation of Modified Ad5 Viral Vector Ad5/H5-HVR1-KWAS-HVR5-His 6
<ol>
	<li>Constitute the complete medium by adding FBS (final 10%), 100X Non-Essential Amino Acids (final 0.1 mM), 200 mM L-glutamine (final 2 mM) and penicillin/streptomycin solution (final 1%) into DMEM with high glucose. Maintain human embryonic kidney (HEK293) cells in complete medium in a culture incubator (37 &#176;C and 5% CO2 under 85% humidified conditions).</li>
	<li>Rescue of viral vector Ad5/H5-HVR1-KWAS-HVR5-His6
	<ol>
		<li>Seed 3.0 x 106 of the HEK293 cells in one T-25 flask containing 5 ml of complete medium and culture O/N to achieve a monolayer with 80% confluence.</li>
		<li>Linearize 15 &#181;g of pAd5/H5-HVR1-KWAS-HVR5-His6 in a 100 &#181;l volume with restriction enzyme PacI (15 units) at 37 &#176;C for 3 hrs.
		<ol>
			<li>Extract linearized pAd5/H5-HVR1-KWAS-HVR5-His6 by centrifuging the reaction twice (10,000 x g for 1 min) with an equal volume of phenol:chloroform:isoamyl alcohol (ratio at 25 : 24 : 1) in a fume hood, and by sequential centrifugation (10,000 x g for 10 min) with a mixed solution (300 &#181;l of 100% ethanol and 10 &#181;l of sodium acetate) and 700 &#181;l of 70% ethanol. Discard supernatant at each centrifugation step.</li>
		</ol>
		</li>
		<li>Resuspend the purified plasmid in ~ 40 &#181;l of distilled water or Tris-EDTA (TE) buffer. Quantitate the plasmid DNA by measuring the optical density (OD) at 260 nm.</li>
		<li>Transfect 3 &#181;g of the linearized plasmid with commercial liposomal transfection reagent in the T-25 flask, according to the manufacturer&#8217;s manual. Change the transfection medium with complete medium at 6 hrs post-transfection and subsequent incubation in the culture incubator. Maintain transfected cells by replacing complete medium every two to three days, until individual viral plaques form.</li>
		<li>When plaques develop to full cytopathic effect (CPE), scrape the remaining cells off the flask in a sterile hood, and harvest cell lysate by centrifuging medium at 300 x g for 10 min at 4 &#176;C. Suspend the cell pellet in ~1 ml of medium containing 2% FBS, and break cells by freeze-thawing four times. Collect the supernatant containing rescued virus after centrifuging lysate at 10,000 x g for 10 min at 4 &#176;C.</li>
	</ol>
	</li>
	<li>Large scale propagation of the viral vector Ad5/H5-HVR1-KWAS-HVR5-His6
	<ol>
		<li>Propagate the virus in a T-75 flask containing HEK293 cells in the sterile hood by infecting with 1/3 to full lysate from the T-25 flask. Allow full CPE to develop within two to three days in the culture incubator. Harvest the lysate supernatant as stated in step 2.2.5.</li>
		<li>Propagate the virus in one to three T-175 flasks in the sterile hood by infecting with 1/2 to full lysate from the T-75 flask, depending on the virus propagation conditions. Allow full CPE to develop within two to three days in the culture incubator. Harvest the lysate supernatant as stated in step 2.2.5.</li>
		<li>Propagate the virus in one dozen or more T-175 flasks in the sterile hood by infecting with 1/2 to full lysate from the previous T-175 flask(s). Determine the amount of flask usage based on the virus propagation conditions and the amount of virus in need. Harvest the lysate supernatant as stated in step 2.2.5 when full CPE occurs within two to three days in the culture incubator.</li>
	</ol>
	</li>
	<li>Purification of Ad5/H5-HVR1-KWAS-HVR5-His6 by caesium chloride
	<ol>
		<li>Prepare two densities of CsCl solutions in 5 mM HEPES: 1.33 g/ml and 1.45 g/ml, while avoiding contact with CsCl.</li>
		<li>Load 4 ml of CsCl (1.33 g/ml) in a sterile ultracentrifuge tube, and gently load 4 ml of CsCl (1.45 g/ml) against bottom of the tube. Load 4 ml of lysate supernatant slowly on top of the gradients in the sterile hood.</li>
		<li>Centrifuge the tube at 110,000 x g for 3 hrs at 4 &#176;C to separate the mature/lower virus band from the defective/higher virus band. Collect the lower band using a 3 ml syringe armed with a 33 G needle and dilute the band with 5 mM HEPES to a 4 ml volume in the sterile hood.</li>
		<li>Load another tube with two densities of CsCl solutions and the diluted band of virus as described in step 2.4.2. Centrifuge the tube at 110,000 x g O/N at 4 &#176;C. Collect the viral band as described in step 2.4.3.</li>
		<li>Inject the collected virus solution in a dialysis cassette by a 3 ml syringe armed with a 33 G needle in the sterile hood.</li>
		<li>Place the cassette in 700 ml of 1x dialysis buffer (1 L&#160;recipe: 100 ml of 10x PBS, 100 ml of 100% glycerol and 800 ml of distilled water; filter the buffer through a 0.22 &#181;m filter) and replace the dialysis buffer every 3 hrs for 4 times. Aspirate out dialyzed virus solution using needled syringe.</li>
	</ol>
	</li>
</ol>
3. Validation of the Rescued Viral Vector
<ol>
	<li>Viral Vector Titrations
	<ol>
		<li>For the virus physical titer, dilute both virus and dialysis buffer (background control) at 1 : 10 and 1 : 20 in virus lysis buffer (10% SDS in Tris-EDTA) in small tubes, and incubate all tubes at 56 &#176;C for 10 min.</li>
		<li>Turn on a biophotometer and set the mode of absorbance at OD 260 nm. Use the diluted dialysis buffer (1 : 10) to balance the background signal by clicking the &#8220;blank&#8221; bottom. Type &#34;10 + 90&#34; in the biophotometer screen, and read the signal of the diluted virus (1 : 10).</li>
		<li>Read the signal of the diluted virus (1 : 20) by following the method in step 3.1.2, but instead type &#34;5 + 95&#34; in the biophotometer screen. Multiply the two virus readout numbers by 1.1x1012 and calculate the average titer with a unit as VP/ml, based on the two individual titers from the two dilutions.</li>
		<li>For the virus infectious titer (IP/ml), use the KARBER statistical TCID50 method14 to determine the infection depth on HEK293 cells at 10 days post infection (d.p.i.)</li>
	</ol>
	</li>
	<li>Evaluation of antigenic exposure display on the viral vector
	<ol>
		<li>Coat the viral vector in an ELISA plate and proceed with the rest of steps in a standard ELISA method14. Use human anti-gp41 (2F5) monoclonal antibody (mAb) and mouse anti-His tag mAb for the detection of corresponding incorporated antigens14.</li>
		<li>Resolve the viral vector in a denatured protein gel electrophoresis (SDS-PAGE) and proceed with the rest of steps in a standard western-blot method14. Use human anti-gp41 (2F5) monoclonal antibody (mAb) and mouse anti-His tag mAb for the detection of corresponding incorporated antigens14.</li>
	</ol>
	</li>
	<li>In vitro evaluation of the vector on the ability to bypass Ad5-positve sera
	<ol>
		<li>Maintain HeLa cells in complete medium in the culture incubator (37 &#176;C and 5% CO2 under 85% humidified conditions). Constitute the complete medium by adding FBS (final 10%), 200 mM L-glutamine (final 2 mM) and penicillin/streptomycin solution (final 1%) into Minimum Essential Medium Eagle (MEME).</li>
		<li>Seed HeLa cells in 6-well plates at 1x106 cells/well, and incubate the plates in the culture incubator (37 &#176;C and 5% CO2 under 85% humidified conditions) for 2 hrs. Incubate Ad5-positive sera (0.1 &#181;l or 0 &#181;l) with 5 IP/cell of viral vector (Ad5 or Ad5/H5-HVR1-KWAS-HVR5-His6) in the culture incubator for 1 hr before adding the mixtures onto the 6-well plates containing cells.</li>
		<li>At 24 hrs post infection (h.p.i.), rinse cells once with PBS and lyse cells in 0.5 ml of lysis buffer. Centrifuge at 15,000 x g for 5 min and collect the supernatant. Mix 20 &#181;l of the supernatant with 100 &#181;l of luciferase substrate for the luciferase signal reading, since viruses contain the luciferase gene.</li>
	</ol>
	</li>
</ol>
4. Immunological Evaluation of the Rescued Viral Vector
<ol>
	<li>Prepare two immunization groups: Ad5 and Ad5/H5-HVR1-KWAS-HVR5-His6.
	<ol>
		<li>Inject mice (n = 8/group) intramuscularly with viruses at 1x1010 VP/mouse, in a homologous &#8220;prime-boost&#8221; immunization regimen, with an interval of 2 weeks.</li>
		<li>At 2 weeks post every injection, bleed mice without anesthesia by cheek bleeding with animal lancets (5 mm tip length) to collect blood in 1.5 ml tubes.</li>
	</ol>
	</li>
	<li>Mix the blood in the tubes by inverting up and down, and incubate the blood at RT for 30 min. Spin the tubes at 10,000 x g for 5 min at 4 &#176;C and transfer sera (top layer) to new 1.5 ml tubes.
	<ol>
		<li>Spin the new tubes at 10,000 x g for 5 min at 4 &#176;C and transfer sera to newly marked 1.5 ml tubes for storage at -80 &#176;C.</li>
	</ol>
	</li>
	<li>Evaluation of antigen-specific humoral immunity by sera-based ELISA
	<ol>
		<li>Dilute His peptide (stock at 1 mM) and HIV-1 peptide (stock at 1 mM) separately in 100.</li>
		<li>mM carbonate buffer (pH 9.5) to achieve the peptide coating concentration at 10 &#181;M. Coat the ELISA plates with the diluted peptides separately by adding 100 &#181;l per well and incubating the plates O/N at 4 &#176;C.</li>
		<li>Wash the plates with PBST for four times at 200 &#181;l/well and block for 1 hr in 5% BSA in PBST. Apply mice sera to the plates at 1 : 100 dilution in the blocking buffer, 100 &#181;l/well. Incubate for 2 hr incubation at RT.</li>
		<li>Wash the plates with PBST for four times. Block the plates by incubating at RT for 30 min&#160;in the blocking buffer at 100 &#181;l/well.</li>
		<li>Apply goat anti-mouse IgG-HRP (1:5000 in the blocking buffer) at 100 &#181;l/well to both the plates coated with His peptide and HIV-1 peptide individually. Incubate for 2 hr at RT. Wash the plates with PBST.</li>
		<li>Read the plates at OD450 nm after incubating with HRP substrate for 30 min.</li>
	</ol>
	</li>
</ol>

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L., 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=Immunization+with+Hexon+Modified+Adenoviral+Vectors+Integrated+with+gp83+Epitope+Provides+Protection+against+Trypanosoma+cruzi+Infection.">Immunization with Hexon Modified Adenoviral Vectors Integrated with gp83 Epitope Provides Protection against Trypanosoma cruzi Infection.</a> PLoS neglected tropical diseases. 8, e3089 (2014).</li><li>Krause, 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=Epitopes+expressed+in+different+adenovirus+capsid+proteins+induce+different+levels+of+epitope-specific+immunity.">Epitopes expressed in different adenovirus capsid proteins induce different levels of epitope-specific immunity.</a> Journal of virology. 80, 5523-5530 (2006).</li><li>Omori, 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=Modification+of+a+fiber+protein+in+an+adenovirus+vector+improves+in+vitro+gene+transfer+efficiency+to+the+mouse+microglial+cell+line.">Modification of a fiber protein in an adenovirus vector improves in vitro gene transfer efficiency to the mouse microglial cell line.</a> Neuroscience letters. 324, 145-148 (2002).</li><li>Dmitriev, I. P., Kashentseva, E. A., Curiel, D. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+of+adenovirus+vectors+containing+heterologous+peptide+sequences+in+the+C+terminus+of+capsid+protein+IX.">Engineering of adenovirus vectors containing heterologous peptide sequences in the C terminus of capsid protein IX.</a> Journal of virology. 76, 6893-6899 (2002).</li><li>Xue, 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=Construction+and+characterization+of+a+recombinant+human+adenovirus+type+3+vector+containing+two+foreign+neutralizing+epitopes+in+hexon.">Construction and characterization of a recombinant human adenovirus type 3 vector containing two foreign neutralizing epitopes in hexon.</a> Virus research. 183, 67-74 (2014).</li><li>Tian, X., 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=Construction+and+characterization+of+human+adenovirus+serotype+3+packaged+by+serotype+7+hexon.">Construction and characterization of human adenovirus serotype 3 packaged by serotype 7 hexon.</a> Virus research. 160, 214-220 (2011).</li><li>Kim, J. W., 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=An+adenovirus+vector+incorporating+carbohydrate+binding+domains+utilizes+glycans+for+gene+transfer.">An adenovirus vector incorporating carbohydrate binding domains utilizes glycans for gene transfer.</a> PloS one. 8, e55533 (2013).</li><li>Vasconcelos, J. 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=Pathogen-induced+proapoptotic+phenotype+and+high+CD95+(Fas)+expression+accompany+a+suboptimal+CD8++T-cell+response:+reversal+by+adenoviral+vaccine.">Pathogen-induced proapoptotic phenotype and high CD95 (Fas) expression accompany a suboptimal CD8+ T-cell response: reversal by adenoviral vaccine.</a> PLoS pathogens. 8, e1002699 (2012).</li><li>Matthews, Q. L., 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=Genetic+incorporation+of+a+herpes+simplex+virus+type+1+thymidine+kinase+and+firefly+luciferase+fusion+into+the+adenovirus+protein+IX+for+functional+display+on+the+virion.">Genetic incorporation of a herpes simplex virus type 1 thymidine kinase and firefly luciferase fusion into the adenovirus protein IX for functional display on the virion.</a> Molecular imaging. 5, 510-519 (2006).</li></ol>

The authors have nothing to disclose.

The application of the traditional transgene strategy on Ad5 modification for the development of vaccines has been diminished primarily due to the bottleneck associated with the Ad5 PEI4,6. This bottleneck can be partially diminished by application of the alternative Antigen Capsid-Incorporation strategy (Figure 1A), since this strategy can evade neutralization by Ad5 NAbs by replacing neutralizing epitopes of Ad5 with antigens-of-interest, and facilitate the generation of robust immunity to t...

Human adenovirus (Ad) is a medium-sized, non-enveloped virus with an icosahedral nucleocapsid containing a double stranded DNA genome. Ad belongs to the Adenoviridae family, with a classification into seven groups (A through G). Each group contains virus of different serotypes. Of which, adenovirus serotype 5 (Ad5) from group C has been the most extensively studied and the most widely applied for vectored approaches like gene therapy and vaccinations.
The traditional transgene strategy has been developed and applied for Ad5 modifications, which is characterized by the displacement of the virus early genes with a gene-of-interest, and the focused expression of the gene-of-interest in a host. Examples are the construction of pENV9/Ad5hr&#8710;E3 by replacing early gene 3 (E3) with rev gene of Simian Immunodeficiency Virus1, the construction of AdCMVGag by replacing early gene 1 (E1) with the gag gene of Human Immunodeficiency Virus (HIV)2, and the construction of AdlacZ by replacing E1 with lacZ gene3. The broad application of the traditional transgene strategy on Ad5 depends on the following merits: the wide range of hosts for Ad5, the feasible gene engineering on virus and virus propagation, the large accommodation of foreign gene insert and the safety of Ad54,5. However, the reduced efficacies of Ad5-vectored clinical therapies by use of this strategy has been a major bottleneck, which has been mapped to be primarily associated with Ad5 PEI, since Ad5 is so prevalent among the majority of children and adults4,6.
To overcome the major bottleneck of Ad5, the primary objective is to develop an alternative strategy circumventing Ad5 PEI. Innate immunity7, adaptive immunity such as neutralizing antibodies (NAbs)8-10 and CD8+ T cell responses10 against Ad5 have been shown to contribute to Ad5 PEI, with Ad5 NAbs appearing to play the dominant role in the contributions to Ad5 PEI10,11. Moreover, Ad5 NAbs target epitopes located in capsid proteins, including the major protein hexon, fiber and penton base. Of which, hexon is the major target of Ad5 NAbs8,11-13. Based on these findings, an innovative Antigen Capsid-Incorporation strategy has been introduced. This novel strategy highlights the replacement or incorporation of proteins-of-interest on Ad5 capsid proteins, which shifts or masks the Ad5 neutralizing epitopes, leading to the decreased recognition by the NAbs and efficient Ad5 vector administrations. It is noteworthy that this strategy is competitive because it can also help hosts elicit robust humoral immunity and potent cellular immunity by directly presenting antigens-of-interest to the immune system4,14,15. Based on this strategy, the molecular cloning and recombinant Ad viral vector rescue can be structurally divided into four main steps: (a) the preparation of gene-of-interest fragment by either polymerase chain reaction (PCR) or synthesis; (b) the ligation of gene fragment into a shuttle plasmid that contains the gene-of-interest fragment and homologous arms to an adenovirus backbone; (c) the homologous recombination by co-transforming the shuttle plasmid containing the gene-of-interest fragment with the linearized backbone plasmid pAd5/&#8710;H5 (GL)16; (d) the transfection of linearized recombinant adenoviral plasmid to rescue the recombinant Ad vector incorporated with antigens-of-interest.
Our group and some others have extended this alternative Ad incorporation strategy for Ad vectored vaccine development against different infectious pathogens. We reported the generation of a recombinant Ad vector Ad-HVR1-lgs-His6-V3 by incorporating a His-tagged HIV-1 antigen V3 into the HVR1 locale of Ad5 hexon (hexon5). This generated vector triggered strong humoral immune response specific to the V3 epitope4. We also reported the development of Ad5/HVR2-MPER-L15&#8710;E1 by incorporating HIV-1 membrane proximal ectodomain region (MPER) into the HVR2 locale of hexon52. In addition, Dr. Zhou&#8217;s group has used the benefits of this Ad incorporation strategy to develop Ad serotype 3 (Ad3) vectored vaccines, i.e., the generation of viral vector R1SP70A3 by incorporating a neutralizing epitope SP70 of Enterovirus 71 into the HVR1 of Ad3 hexon (hexon3). R1SP70A3 generated strong NAbs and IFN-&#947; production specific to the epitope SP70, which lead to the high rate of protection against Enterovirus 71 challenge15.
For the purpose of technical reference, our study took advantage of the qualitative Antigen Capsid-Incorporation strategy to focus on the generation of a divalent Ad5 vector Ad5/H5-HVR1-KWAS-HVR5-His6 by incorporating an HIV-1 antigen into HVR1 and a His tag into HVR5 of hexon5. The generated viral vector was also immunologically evaluated. The Antigen Capsid-Incorporation strategy could be utilized towards the development of Ad5-vectored vaccination approaches against different infectious diseases.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>1x DPBS</td>
			<td>Thermo Scientific</td>
			<td>SH30256.01</td>
			<td>for cell spliting&#160;</td>
		</tr>
		<tr>
			<td>10x DPBS</td>
			<td>Thermo Scientific</td>
			<td>SH30378.02</td>
			<td>for dialysis buffer preparation</td>
		</tr>
		<tr>
			<td>glycerol</td>
			<td>SIGMA</td>
			<td>G5516-1L</td>
			<td>for dialysis buffer preparation</td>
		</tr>
		<tr>
			<td>SDS</td>
			<td>BIO-RAD</td>
			<td>161-0301</td>
			<td>for virus lysis buffer preparation</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Thermo Scientific</td>
			<td>SH30910.03</td>
			<td>component of culture medium</td>
		</tr>
		<tr>
			<td>100X Non-Essential Amino Acids&#160;</td>
			<td>Thermo Scientific</td>
			<td>SH30238.01</td>
			<td>component of culture medium</td>
		</tr>
		<tr>
			<td>200mM/L L-glutamine</td>
			<td>Cellgro</td>
			<td>25-005-CI</td>
			<td>component of culture medium</td>
		</tr>
		<tr>
			<td>penicillin/streptomycin solution&#160;</td>
			<td>Cellgro</td>
			<td>30-002-CI</td>
			<td>component of culture medium</td>
		</tr>
		<tr>
			<td>DMEM with high glucose</td>
			<td>Thermo Scientific</td>
			<td>SH30081.01</td>
			<td>for HEK293 cell culture</td>
		</tr>
		<tr>
			<td>Minimum Essential Medium Eagle</td>
			<td>SIGMA</td>
			<td>M5650</td>
			<td>for HeLa cell culture</td>
		</tr>
		<tr>
			<td>phenol:chloroform:isoamyl alcohol&#160;</td>
			<td>SIGMA</td>
			<td>P3803-100ML</td>
			<td>for large size of DNA purification</td>
		</tr>
		<tr>
			<td>cesium chloride&#160;</td>
			<td>Research Products International Corp.</td>
			<td>C68050</td>
			<td>for virus purificiation</td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>Cellgro</td>
			<td>25-060-CI</td>
			<td>for CsCl solution preparation</td>
		</tr>
		<tr>
			<td>HEK293</td>
			<td>ATCC</td>
			<td>51-0036</td>
			<td>for virus rescue and upscale</td>
		</tr>
		<tr>
			<td>HeLa</td>
			<td>ATCC</td>
			<td>CCL-2</td>
			<td>for neutralization assay</td>
		</tr>
		<tr>
			<td>T-25 flask</td>
			<td>Thermo Scientific</td>
			<td>156367</td>
			<td>for cell culture&#160;</td>
		</tr>
		<tr>
			<td>T-75 flask</td>
			<td>CORNING</td>
			<td>430641</td>
			<td>for cell culture&#160;</td>
		</tr>
		<tr>
			<td>T-175 flask</td>
			<td>Thermo Scientific</td>
			<td>159910</td>
			<td>for cell culture&#160;</td>
		</tr>
		<tr>
			<td>Ultracentrifuge</td>
			<td>BECKMAN</td>
			<td>NA</td>
			<td>for virus purification</td>
		</tr>
		<tr>
			<td>Ultracentrifuge tube</td>
			<td>BECKMAN</td>
			<td>344059</td>
			<td>for virus purification</td>
		</tr>
		<tr>
			<td>dialysis cassette&#160;</td>
			<td>Thermo Scientific</td>
			<td>66380</td>
			<td>for virus dialysis</td>
		</tr>
		<tr>
			<td>ELISA plate</td>
			<td>Thermo Scientific</td>
			<td>442404</td>
			<td>for ELISA</td>
		</tr>
		<tr>
			<td>human anti-gp41 (2F5) mAb</td>
			<td>NIH AIDS Reagent Program</td>
			<td>1475</td>
			<td>for immunological assays</td>
		</tr>
		<tr>
			<td>mouse anti-His tag mAb</td>
			<td>GenScript</td>
			<td>A00186</td>
			<td>for immunological assays</td>
		</tr>
		<tr>
			<td>SOC medium</td>
			<td>CORNING</td>
			<td>46-003-CR</td>
			<td>for transformation</td>
		</tr>
		<tr>
			<td>PCR master mix solution</td>
			<td>QIAGEN</td>
			<td>201445</td>
			<td>for PCR</td>
		</tr>
		<tr>
			<td>Animal lancet (point length at 5mm)</td>
			<td>MEDIpoint</td>
			<td></td>
			<td>for mice bleeding&#160;</td>
		</tr>
		<tr>
			<td>Biophotometer</td>
			<td>Eppendorf</td>
			<td></td>
			<td>for virus physical titer titration</td>
		</tr>
	</tbody>
</table>

utilizing the antigen capsid-incorporation strategy for the development of adenovirus serotype 5-vectored vaccine approaches

Adenovirus serotype 5 (Ad5) has been extensively modified with traditional transgene methods for the vaccine development. The reduced efficacies of these traditionally modified Ad5 vectors in clinical trials could be primarily correlated with Ad5 pre-existing immunity (PEI) among the majority of the population. To promote Ad5-vectored vaccine development by solving the concern of Ad5 PEI, the innovative Antigen Capsid-Incorporation strategy has been employed. By merit of this strategy, Ad5-vectored we first constructed the hexon shuttle plasmid HVR1-KWAS-HVR5-His6/pH5S by subcloning the hypervariable region (HVR) 1 of hexon into a previously constructed shuttle plasmid HVR5-His6/pH5S, which had His6 tag incorporated into the HVR5. This HVR1 DNA fragment containing a HIV epitope ELDKWAS was synthesized. HVR1-KWAS-HVR5-His6/pH5S was then linearized and co-transformed with linearized backbone plasmid pAd5/&#8710;H5 (GL) , for homologous recombination. This recombined plasmid pAd5/H5-HVR1-KWAS-HVR5-His6 was transfected into cells to generate the viral vector Ad5/H5-HVR1-KWAS-HVR5-His6. This vector was validated to have qualitative fitness indicated by viral physical titer (VP/ml), infectious titer (IP/ml) and corresponding VP/IP ratio. Both the HIV epitope and His6 tag were surface-exposed on the Ad5 capsid, and retained epitope-specific antigenicity of their own. A neutralization assay indicated the ability of this divalent vector to circumvent neutralization by Ad5-positive sera in vitro. Mice immunization demonstrated the generation of robust humoral immunity specific to the HIV epitope and His6. This proof-of-principle study suggested that the protocol associated with the Antigen Capsid-Incorporation strategy could be feasibly utilized for the generation of Ad5-vectored vaccines by modifying different capsid proteins. This protocol could even be further modified for the generation of rare-serotype adenovirus-vectored vaccines.

The Antigen Capsid-Incorporation strategy (Figure 1A) was utilized to generate the divalent Ad5 viral vector Ad5/H5-HVR1-KWAS-HVR5-His6. Firstly, the shuttle plasmid HVR1-KWAS-HVR5-His6/pH5S was constructed by subcloning HVR1-KWAS fragment into the previous constructed shuttle plasmid HVR5-His6/pH5S17. Secondly, the plasmid pAd5/H5-HVR1-KWAS-HVR5-His614 was constructed by a homologous recombination between the fragment of &#8220;EcoRI-HVR1...

Watch this Scientific Journal Video about Utilizing the Antigen Capsid-Incorporation Strategy for the Development of Adenovirus Serotype 5-Vectored Vaccine Approaches at JoVE.com

Utilizing the Antigen Capsid-Incorporation Strategy for the Development of Adenovirus Serotype 5-Vectored Vaccine Approaches

Here, we present a protocol to generate a proof-of-principle divalent adenovirus type 5 (Ad5) vector Ad5/H5-HVR1-KWAS-HVR5-His6 by utilizing the Antigen Capsid-Incorporation strategy. This vector was demonstrated to exhibit qualitative fitness, the capability to escape Ad5-positive sera in vitro, and the antigenicity as well as immunogenicity to the incorporated antigens.

Adenovirus serotype 5 (Ad5) has been extensively modified with traditional transgene methods for the vaccine development. The reduced efficacies of these ...

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JoVE Journal

Immunology and Infection

10.3K Views.  University of Alabama at Birmingham. Here, we present a protocol to generate a proof-of-principle divalent adenovirus type 5 (Ad5) vector Ad5/H5-HVR1-KWAS-HVR5-His6 by utilizing the Antigen Capsid-Incorporation strategy. This vector was demonstrated to exhibit qualitative fitness, the capability to escape Ad5-positive sera in vitro, and the antigenicity as well as immunogenicity to the incorporated antigens.

Video: Utilizing the Antigen Capsid-Incorporation Strategy for the Development of Adenovirus Serotype 5-Vectored Vaccine Approaches

Efficient Recombinant Parvovirus Production with the Help of Adenovirus-derived Systems

Rodent parvoviruses (PV) such as rat H-1PV and MVM, are small icosahedral, single stranded, DNA viruses. Their genome includes two promoters P4 and P38 which regulate the expression of non-structural (NS1 and NS2) and capsid proteins (VP1 and VP2) respectively1. They attract high interest as anticancer agents for their oncolytic and oncosuppressive abilities while being non-pathogenic for humans2. NS1 is the major effector of viral cytotoxicity3. In order to further enhance their natural antineoplastic activities, derivatives from these vectors have been generated by replacing the gene encoding for the capsid proteins with a therapeutic transgene (e.g. a cytotoxic polypeptide, cytokine, chemokine, tumour suppressor gene etc.)4. The recombinant parvoviruses (recPVs) vector retains the NS1/2 coding sequences and the PV genome telomeres which are necessary for viral DNA amplification and packaging. Production of recPVs occurs only in the producer cells (generally HEK293T), by co-transfecting the cells with a second vector (pCMV-VP) expressing the gene encoding for the VP proteins (Fig. 1)4. The recPV vectors generated in this way are replication defective. Although recPVs proved to possess enhanced oncotoxic activities with respect to the parental viruses from which they have been generated, their production remains a major challenge and strongly hampers the use of these agents in anti-cancer clinical applications.
We found that introduction of an Ad-5 derived vector containing the E2a, E4(orf6) and the VA RNA genes (e.g. pXX6 plasmid) into HEK293T improved the production of recPVs by more than 10 fold in comparison to other protocols in use. Based on this finding, we have constructed a novel Ad-VP-helper that contains the genomic adenoviral elements necessary to enhance recPVs production as well as the parvovirus VP gene unit5. The use of Ad-VP-helper, allows production of rec-PVs using a protocol that relies entirely on viral infection steps (as opposed to plasmid transfection), making possible the use of cell lines that are difficult to transfect (e.g. NB324K) (Fig. 2). We present a method that greatly improves the amount of recombinant virus produced, reducing both the production time and costs, without affecting the quality of the final product5. In addition, large scale production of recPV (in suspension cells and bioreactors) is now conceivable.

Here we describe a protocol based only on cell infection, which improves the efficiency of recombinant parvovirus production by more than 100 fold in comparison to other protocols in use. This protocol relies on the use of a novel adenovirus 5-based helper containing the parvovirus VP transcription unit (Ad-VP).

Rodent parvoviruses (PV) such as rat H-1PV and MVM, are small icosahedral, single stranded, DNA viruses. Their genome includes two promoters P4 and P38 ...

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

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

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

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

Using Click Chemistry to Measure the Effect of Viral Infection on Host-Cell RNA Synthesis

Many RNA viruses have evolved the ability to inhibit host cell transcription as a means to circumvent cellular defenses. For the study of these viruses, it is therefore important to have a quick and reliable way of measuring transcriptional activity in infected cells. Traditionally, transcription has been measured either by incorporation of radioactive nucleosides such as 3H-uridine followed by detection via autoradiography or scintillation counting, or incorporation of halogenated uridine analogs such as 5-bromouridine (BrU) followed by detection via immunostaining. The use of radioactive isotopes, however, requires specialized equipment and is not feasible in a number of laboratory settings, while the detection of BrU can be cumbersome and may suffer from low sensitivity.
The recently developed click chemistry, which involves a copper-catalyzed triazole formation from an azide and an alkyne, now provides a rapid and highly sensitive alternative to these two methods. Click chemistry is a two step process in which nascent RNA is first labeled by incorporation of the uridine analog 5-ethynyluridine (EU), followed by detection of the label with a fluorescent azide. These azides are available as several different fluorophores, allowing for a wide range of options for visualization.
This protocol describes a method to measure transcriptional suppression in cells infected with the Rift Valley fever virus (RVFV) strain MP-12 using click chemistry. Concurrently, expression of viral proteins in these cells is determined by classical intracellular immunostaining. Steps 1 through 4 detail a method to visualize transcriptional suppression via fluorescence microscopy, while steps 5 through 8 detail a method to quantify transcriptional suppression via flow cytometry. This protocol is easily adaptable for use with other viruses.

This method describes the use of click chemistry to measure changes in host cell transcription after infection with the Rift Valley fever virus (RVFV) strain MP-12. Results can be visualized qualitatively via fluorescence microscopy or obtained quantitatively through flow cytometry. This method is adaptable for use with other viruses.

Many RNA viruses have evolved the ability to inhibit host cell transcription as a means to circumvent cellular defenses. For the study of these viruses, ...

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

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

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

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

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 ...

Detection of Human Leukocyte Antigen Biomarkers in Breast Cancer Utilizing Label-free Biosensor Technology

According to the American Cancer Society, more than 200,000 women will be diagnosed with invasive breast cancer each year and approximately 40,000 will die from the disease. The human leukocyte antigen (HLA) class I samples peptides derived from proteasomal degradation of cellular proteins and presents these fragments on the cell surface for interrogation by circulating cytotoxic T lymphocytes (CTL). Generation of T-cell receptor mimic (TCRm) monoclonal antibodies (mAbs) which recognize breast cancer specific peptide/HLA-A*02:01 complexes such as those derived from macrophage migration inhibitory factor (MIF19-27) and NY-ESO-1157-165 enable detection and destruction of breast cancer cells in the absence of an effective anti-tumor CTL response. Intact class I HLA/peptide complexes are shed by breast cancer cells and represent potentially relevant cancer biomarkers. In this work, a breakthrough biomarker screening system for cancer diagnostics incorporating T-cell receptor mimic monoclonal antibodies combined with a novel, label-free biosensor utilizing guided-mode resonance (GMR) sensor technology is presented. Detection of shed MIF/HLA-A*02:01 complexes in MDA-MB-231 cell supernatants, spiked human serum, and patient plasma is demonstrated. The impact of this work could revolutionize personalized medicine through development of companion disease diagnostics for targeted immunotherapies.

Intact class I HLA/peptide complexes are shed by cancer cells, representing a potential relevant cancer biomarker. Utilizing label-free sensor technology and T-cell receptor mimicking monoclonal antibodies, detection of shed MIF/HLA-A*02:01 complexes in MDA-MB-231 cell supernatants, spiked human serum, and patient plasma is demonstrated, enabling development of a novel cancer diagnostic platform.

According to the American Cancer Society, more than 200,000 women will be diagnosed with invasive breast cancer each year and approximately 40,000 will ...

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

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

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

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

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

Imaging CD4 T Cell Interstitial Migration in the Inflamed Dermis

The ability of CD4 T cells to carry out effector functions is dependent upon the rapid and efficient migration of these cells in inflamed peripheral tissues through an as-yet undefined mechanism. The application of multiphoton microscopy to the study of the immune system provides a tool to measure the dynamics of immune responses within intact tissues. Here we present a protocol for non-invasive intravital multiphoton imaging of CD4 T cells in the inflamed mouse ear dermis. Use of a custom imaging platform and a venous catheter allows for the visualization of CD4 T cell dynamics in the dermal interstitium, with the ability to interrogate these cells in real-time via the addition of blocking antibodies to key molecular components involved in motility. This system provides advantages over both in vitro models and surgically invasive imaging procedures. Understanding the pathways used by CD4 T cells for motility may ultimately provide insight into the basic function of CD4 T cells as well as the pathogenesis of both autoimmune diseases and pathology from chronic infections.

The mechanisms that govern the interstitial motility of CD4 effector T cells at sites of inflammation are relatively unknown. We present a non-invasive approach to visualize and manipulate in vitro-primed CD4 T cells in the inflamed ear dermis, allowing for study of the dynamic behavior of these cells in situ.

The ability of CD4 T cells to carry out effector functions is dependent upon the rapid and efficient migration of these cells in inflamed peripheral ...

Development of Stem Cell-derived Antigen-specific Regulatory T Cells Against Autoimmunity

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic self-tolerance. Tregs represent about 5 - 10% of the mature CD4+ T cell subpopulation in mice and humans, with about 1 - 2% of those Tregs circulating in the peripheral blood. Induced pluripotent stem cells (iPSCs) can be differentiated into functional Tregs, which have a potential to be used for cell-based therapies of autoimmune diseases. Here, we present a method to develop antigen (Ag)-specific Tregs from iPSCs (i.e., iPSC-Tregs). The method is based on incorporating the transcription factor FoxP3 and an Ag-specific T cell receptor (TCR) into iPSCs and then differentiating on OP9 stromal cells expressing Notch ligands delta-like (DL) 1 and DL4. Following in vitro differentiation, the iPSC-Tregs express CD4, CD8, CD3, CD25, FoxP3, and Ag-specific TCR and are able to respond to Ag stimulation. This method has been successfully applied to cell-based therapy of autoimmune arthritis in a murine model. Adoptive transfer of these Ag-specific iPSC-Tregs into Ag-induced arthritis (AIA)-bearing mice has the ability to reduce joint inflammation and swelling and to prevent bone loss.

We present here a method to develop functional antigen (Ag)-specific regulatory T cells (Tregs) from induced pluripotent stem cells (iPSCs) for immunotherapy of autoimmune arthritis in a murine model.

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic ...

Evaluation of Host-Pathogen Responses and Vaccine Efficacy in Mice

Vaccines are a 20th century medical marvel. They have dramatically reduced the morbidity and mortality caused by infectious diseases and contributed to a striking increase in life expectancy around the globe. Nonetheless, determining vaccine efficacy remains a challenge. Emerging evidence suggests that the current acellular vaccine (aPV) for Bordetella pertussis (B. pertussis) induces suboptimal immunity. Therefore, a major challenge is designing a next-generation vaccine that induces protective immunity without the adverse side effects of a whole-cell vaccine (wPV). Here we describe a protocol that we used to test the efficacy of a promising, novel adjuvant that skews immune responses to a protective Th1/Th17 phenotype and promotes a better clearance of a B. pertussis challenge from the murine respiratory tract. This article describes the protocol for mouse immunization, bacterial inoculation, tissue harvesting, and analysis of immune responses. Using this method, within our model, we have successfully elucidated crucial mechanisms elicited by a promising, next-generation acellular pertussis vaccine. This method can be applied to any infectious disease model in order to determine vaccine efficacy.

Here we present an elegant protocol for in vivo evaluation of vaccine effectiveness and host immune responses. This protocol can be adapted for vaccine models that study viral, bacterial, or parasitic pathogens.

Vaccines are a 20th century medical marvel. They have dramatically reduced the morbidity and mortality caused by infectious diseases and contributed to a ...

Use of an Influenza Antigen Microarray to Measure the Breadth of Serum Antibodies Across Virus Subtypes

The influenza virus remains a significant cause of mortality worldwide due to the limited effectiveness of currently available vaccines. A key challenge to the development of universal influenza vaccines is high antigenic diversity resulting from antigenic drift. Overcoming this challenge requires novel research tools to measure the breadth of serum antibodies directed against many virus strains across different antigenic subtypes. Here, we present a protocol for analyzing the breadth of serum antibodies against diverse influenza virus strains using a protein microarray of influenza antigens.
This influenza antigen microarray is constructed by printing purified hemagglutinin and neuraminidase antigens onto a nitrocellulose-coated membrane using a microarray printer. Human sera are incubated on the microarray to bind antibodies against the influenza antigens. Quantum-dot-conjugated secondary antibodies are used to simultaneously detect IgG and IgA antibodies binding to each antigen on the microarray. Quantitative antibody binding is measured as fluorescence intensity using a portable imager. Representative results are shown to demonstrate assay reproducibility in measuring subtype-specific and cross-reactive influenza antibodies in human sera.
Compared to traditional methods such as ELISA, the influenza antigen microarray provides a high throughput multiplexed approach capable of testing hundreds of sera for multiple antibody isotypes against hundreds of antigens in a short time frame, and thus has applications in sero-surveillance and vaccine development. A limitation is the inability to distinguish binding antibodies from neutralizing antibodies.

We present a protocol for using a protein microarray constructed by printing influenza antigens onto nitrocellulose-coated slides to simultaneously probe serum for multiple antibody isotypes against over 250 antigens from different virus strains, thus allowing measurement of the breadth of serum antibodies across virus subtypes.

The influenza virus remains a significant cause of mortality worldwide due to the limited effectiveness of currently available vaccines. A key challenge ...