A nonreplicating subunit vaccine protects mice against lethal Ebola virus challenge

PubMed Central

Phoolcharoen, Waranyoo; Dye, John M.; Kilbourne, Jacquelyn; Piensook, Khanrat; Pratt, William D.; Arntzen, Charles J.; Chen, Qiang; Mason, Hugh S.; Herbst-Kralovetz, Melissa M.

2011-01-01

Ebola hemorrhagic fever is an acute and often deadly disease caused by Ebola virus (EBOV). The possible intentional use of this virus against human populations has led to design of vaccines that could be incorporated into a national stockpile for biological threat reduction. We have evaluated the immunogenicity and efficacy of an EBOV vaccine candidate in which the viral surface glycoprotein is biomanufactured as a fusion to a monoclonal antibody that recognizes an epitope in glycoprotein, resulting in the production of Ebola immune complexes (EICs). Although antigen–antibody immune complexes are known to be efficiently processed and presented to immune effector cells, we found that codelivery of the EIC with Toll-like receptor agonists elicited a more robust antibody response in mice than did EIC alone. Among the compounds tested, polyinosinic:polycytidylic acid (PIC, a Toll-like receptor 3 agonist) was highly effective as an adjuvant agent. After vaccinating mice with EIC plus PIC, 80% of the animals were protected against a lethal challenge with live EBOV (30,000 LD50 of mouse adapted virus). Surviving animals showed a mixed Th1/Th2 response to the antigen, suggesting this may be important for protection. Survival after vaccination with EIC plus PIC was statistically equivalent to that achieved with an alternative viral vector vaccine candidate reported in the literature. Because nonreplicating subunit vaccines offer the possibility of formulation for cost-effective, long-term storage in biothreat reduction repositories, EIC is an attractive option for public health defense measures. PMID:22143779

Inactivated H7 Influenza Virus Vaccines Protect Mice despite Inducing Only Low Levels of Neutralizing Antibodies.

PubMed

Kamal, Ram P; Blanchfield, Kristy; Belser, Jessica A; Music, Nedzad; Tzeng, Wen-Pin; Holiday, Crystal; Burroughs, Ashley; Sun, Xiangjie; Maines, Taronna R; Levine, Min Z; York, Ian A

2017-10-15

Avian influenza viruses of the H7 hemagglutinin (HA) subtype present a significant public health threat, as evidenced by the ongoing outbreak of human A(H7N9) infections in China. When evaluated by hemagglutination inhibition (HI) and microneutralization (MN) assays, H7 viruses and vaccines are found to induce lower level of neutralizing antibodies (nAb) than do their seasonal counterparts, making it difficult to develop and evaluate prepandemic vaccines. We have previously shown that purified recombinant H7 HA appear to be poorly immunogenic in that they induce low levels of HI and MN antibodies. In this study, we immunized mice with whole inactivated reverse genetics reassortant (RG) viruses expressing HA and neuraminidase (NA) from 3 different H7 viruses [A/Shanghai/2/2013(H7N9), A/Netherlands/219/2003(H7N7), and A/New York/107/2003(H7N2)] or with human A(H1N1)pdm09 (A/California/07/2009-like) or A(H3N2) (A/Perth16/2009) viruses. Mice produced equivalent titers of antibodies to all viruses as measured by enzyme-linked immunosorbent assay (ELISA). However, the antibody titers induced by H7 viruses were significantly lower when measured by HI and MN assays. Despite inducing very low levels of nAb, H7 vaccines conferred complete protection against homologous virus challenge in mice, and the serum antibodies directed against the HA head region were capable of mediating protection. The apparently low immunogenicity associated with H7 viruses and vaccines may be at least partly related to measuring antibody titers with the traditional HI and MN assays, which may not provide a true measure of protective immunity associated with H7 immunization. This study underscores the need for development of additional correlates of protection for prepandemic vaccines. IMPORTANCE H7 avian influenza viruses present a serious risk to human health. Preparedness efforts include development of prepandemic vaccines. For seasonal influenza viruses, protection is correlated with antibody

Inactivated H7 Influenza Virus Vaccines Protect Mice despite Inducing Only Low Levels of Neutralizing Antibodies

PubMed Central

Blanchfield, Kristy; Belser, Jessica A.; Music, Nedzad; Tzeng, Wen-Pin; Holiday, Crystal; Burroughs, Ashley; Sun, Xiangjie; Maines, Taronna R.; Levine, Min Z.; York, Ian A.

2017-01-01

ABSTRACT Avian influenza viruses of the H7 hemagglutinin (HA) subtype present a significant public health threat, as evidenced by the ongoing outbreak of human A(H7N9) infections in China. When evaluated by hemagglutination inhibition (HI) and microneutralization (MN) assays, H7 viruses and vaccines are found to induce lower level of neutralizing antibodies (nAb) than do their seasonal counterparts, making it difficult to develop and evaluate prepandemic vaccines. We have previously shown that purified recombinant H7 HA appear to be poorly immunogenic in that they induce low levels of HI and MN antibodies. In this study, we immunized mice with whole inactivated reverse genetics reassortant (RG) viruses expressing HA and neuraminidase (NA) from 3 different H7 viruses [A/Shanghai/2/2013(H7N9), A/Netherlands/219/2003(H7N7), and A/New York/107/2003(H7N2)] or with human A(H1N1)pdm09 (A/California/07/2009-like) or A(H3N2) (A/Perth16/2009) viruses. Mice produced equivalent titers of antibodies to all viruses as measured by enzyme-linked immunosorbent assay (ELISA). However, the antibody titers induced by H7 viruses were significantly lower when measured by HI and MN assays. Despite inducing very low levels of nAb, H7 vaccines conferred complete protection against homologous virus challenge in mice, and the serum antibodies directed against the HA head region were capable of mediating protection. The apparently low immunogenicity associated with H7 viruses and vaccines may be at least partly related to measuring antibody titers with the traditional HI and MN assays, which may not provide a true measure of protective immunity associated with H7 immunization. This study underscores the need for development of additional correlates of protection for prepandemic vaccines. IMPORTANCE H7 avian influenza viruses present a serious risk to human health. Preparedness efforts include development of prepandemic vaccines. For seasonal influenza viruses, protection is correlated with

Vaccination with Brucella abortus rough mutant RB51 protects BALB/c mice against virulent strains of Brucella abortus, Brucella melitensis, and Brucella ovis.

PubMed Central

Jiménez de Bagüés, M P; Elzer, P H; Jones, S M; Blasco, J M; Enright, F M; Schurig, G G; Winter, A J

1994-01-01

Vaccination of BALB/c mice with live Brucella abortus RB51, a stable rough mutant, produced protection against challenge with virulent strains of Brucella abortus, Brucella melitensis, and Brucella ovis. Passive-transfer experiments indicated that vaccinated mice were protected against B. abortus 2308 through cell-mediated immunity, against B. ovis PA through humoral immunity, and against B. melitensis 16M through both forms of immunity. Live bacteria were required for the induction of protective cell-mediated immunity; vaccination with whole killed cells of strain RB51 failed to protect mice against B. abortus 2308 despite development of good delayed-type hypersensitivity reactions. Protective antibodies against the heterologous species were generated in vaccinated mice primarily through anamnestic responses following challenge infections. Growth of the antigenically unrelated bacterium Listeria monocytogenes in the spleens of vaccinated mice indicated that nonspecific killing by residual activated macrophages contributed minimally to protection. These results encourage the continued investigation of strain RB51 as an alternative vaccine against heterologous Brucella species. However, its usefulness against B. ovis would be limited if, as suggested here, epitopes critical for protective cell-mediated immunity are not shared between B. abortus and B. ovis. Images PMID:7927779

Conventional influenza vaccines influence the performance of a universal influenza vaccine in mice.

PubMed

Rowell, Janelle; Lo, Chia-Yun; Price, Graeme E; Misplon, Julia A; Epstein, Suzanne L; Garcia, Mayra

2018-02-08

Universal influenza vaccines are designed to protect against diverse strains of influenza virus. Preclinical testing of new vaccine candidates is usually done in naïve animals, despite intended use in the human population with its varied immune history including responses to previous vaccinations. As an approach more relevant to human use, we tested a candidate universal influenza vaccine in mice with a history of conventional vaccination. Female BALB/c mice were given two intramuscular doses of inactivated influenza vaccine (IIV) or diphtheria and tetanus toxoids vaccine (DT), one month apart. Another group was given two intranasal doses of live attenuated influenza virus (LAIV). One month after the second dose, mice were given the universal influenza vaccine: recombinant adenoviruses expressing influenza A nucleoprotein (A/NP) and matrix 2 (M2) (A/NP + M2-rAd). Immune responses to universal vaccine antigens A/NP and M2 were assessed by ELISA and interferon-γ ELISPOT. Protection was tested by challenge with mouse-adapted A/FM/1/47 (H1N1) and monitoring for weight loss and survival. Universal vaccine performance was enhanced, inhibited or unaffected by particular prior vaccinations. Mice given Afluria IIV and LAIV had greater antibody and T-cell response to A/NP than mice without prior vaccination, providing examples of enhanced A/NP + M2-rAd performance. Though Fluvirin IIV partially inhibited, the universal vaccine still provided considerable protection unlike conventional vaccination. Fluzone IIV and DT had no effect on A/NP + M2-rAd performance. Thus our results demonstrate that universal vaccine candidate A/NP + M2-rAd was at least partially effective in mice with diverse prior histories. However, the degree of protection and nature of the immune responses may be affected by a history of conventional vaccination and suggests that performance in humans would be influenced by immune history. Published by Elsevier Ltd.

Protective immunity conferred by porcine circovirus 2 ORF2-based DNA vaccine in mice.

PubMed

Sylla, Seydou; Cong, Yan-Long; Sun, Yi-Xue; Yang, Gui-Lian; Ding, Xue-Mei; Yang, Zhan-Qing; Zhou, Yu-Long; Yang, Minnan; Wang, Chun-Feng; Ding, Zhuang

2014-07-01

Post-weaning multisystemic wasting syndrome (PMWS) associated with porcine circovirus type 2 (PCV2) has caused the swine industry significant health challenges and economic damage. Although inactivated and subunit vaccines against PMWS have been used widely, so far no DNA vaccine is available. In this study, with the aim of exploring a new route for developing a vaccine against PCV2, the immunogenicity of a DNA vaccine was evaluated in mice. The pEGFP-N1 vector was used to construct a PCV2 Cap gene recombinant vaccine. To assess the immunogenicity of pEGFP-Cap, 80 BALB/c mice were immunized three times at 2 weekly intervals with pEGFP-Cap, LG-strain vaccine, pEGFP-N1 vector or PBS and then challenged with PCV2. IgG and cytokines were assessed by indirect ELISA and ELISA, respectively. Specimens stained with hematoxylin and eosin (HE) and immunohistochemistry (IHC) techniques were examined histopathologically. It was found that vaccination of the mice with the pEGFP-Cap induced solid protection against PCV2 infection through induction of highly specific serum IgG antibodies and cytokines (IFN-γ and IL-10), and a small PCV2 viral load. The mice treated with the pEGFP-Cap and LG-strain developed no histopathologically detectable lesions (HE stain) and IHC techniques revealed only a few positive cells. Thus, this study demonstrated that recombinant pEGFP-Cap substantially alleviates PCV2 infection in mice and provides evidence that a DNA vaccine could be an alternative to PCV2 vaccines against PMWS. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.

Vaccination with Recombinant Cryptococcus Proteins in Glucan Particles Protects Mice against Cryptococcosis in a Manner Dependent upon Mouse Strain and Cryptococcal Species.

PubMed

Specht, Charles A; Lee, Chrono K; Huang, Haibin; Hester, Maureen M; Liu, Jianhua; Luckie, Bridget A; Torres Santana, Melanie A; Mirza, Zeynep; Khoshkenar, Payam; Abraham, Ambily; Shen, Zu T; Lodge, Jennifer K; Akalin, Ali; Homan, Jane; Ostroff, Gary R; Levitz, Stuart M

2017-11-28

Development of a vaccine to protect against cryptococcosis is a priority given the enormous global burden of disease in at-risk individuals. Using glucan particles (GPs) as a delivery system, we previously demonstrated that mice vaccinated with crude Cryptococcus -derived alkaline extracts were protected against lethal challenge with Cryptococcus neoformans and Cryptococcus gattii The goal of the present study was to identify protective protein antigens that could be used in a subunit vaccine. Using biased and unbiased approaches, six candidate antigens (Cda1, Cda2, Cda3, Fpd1, MP88, and Sod1) were selected, recombinantly expressed in Escherichia coli , purified, and loaded into GPs. Three mouse strains (C57BL/6, BALB/c, and DR4) were then vaccinated with the antigen-laden GPs, following which they received a pulmonary challenge with virulent C. neoformans and C. gattii strains. Four candidate vaccines (GP-Cda1, GP-Cda2, GP-Cda3, and GP-Sod1) afforded a significant survival advantage in at least one mouse model; some vaccine combinations provided added protection over that seen with either antigen alone. Vaccine-mediated protection against C. neoformans did not necessarily predict protection against C. gattii Vaccinated mice developed pulmonary inflammatory responses that effectively contained the infection; many surviving mice developed sterilizing immunity. Predicted T helper cell epitopes differed between mouse strains and in the degree to which they matched epitopes predicted in humans. Thus, we have discovered cryptococcal proteins that make promising candidate vaccine antigens. Protection varied depending on the mouse strain and cryptococcal species, suggesting that a successful human subunit vaccine will need to contain multiple antigens, including ones that are species specific. IMPORTANCE The encapsulated fungi Cryptococcus neoformans and Cryptococcus gattii are responsible for nearly 200,000 deaths annually, mostly in immunocompromised individuals. An

A multiagent filovirus DNA vaccine delivered by intramuscular electroporation completely protects mice from ebola and Marburg virus challenge.

PubMed

Grant-Klein, Rebecca J; Van Deusen, Nicole M; Badger, Catherine V; Hannaman, Drew; Dupuy, Lesley C; Schmaljohn, Connie S

2012-11-01

We evaluated the immunogenicity and protective efficacy of DNA vaccines expressing the codon-optimized envelope glycoprotein genes of Zaire ebolavirus, Sudan ebolavirus, and Marburg marburgvirus (Musoke and Ravn). Intramuscular or intradermal delivery of the vaccines in BALB/c mice was performed using the TriGrid™ electroporation device. Mice that received DNA vaccines against the individual viruses developed robust glycoprotein-specific antibody titers as determined by ELISA and survived lethal viral challenge with no display of clinical signs of infection. Survival curve analysis revealed there was a statistically significant increase in survival compared to the control groups for both the Ebola and Ravn virus challenges. These data suggest that further analysis of the immune responses generated in the mice and additional protection studies in nonhuman primates are warranted.

Immunogenicity and Protective Efficacy in Mice and Hamsters of a β-Propiolactone Inactivated Whole Virus SARS-CoV Vaccine

PubMed Central

Roberts, Anjeanette; Lamirande, Elaine W.; Vogel, Leatrice; Baras, Benoît; Goossens, Geneviève; Knott, Isabelle; Chen, Jun; Ward, Jerrold M.; Vassilev, Ventzislav

2010-01-01

Abstract The immunogenicity and efficacy of β-propiolactone (BPL) inactivated whole virion SARS-CoV (WI-SARS) vaccine was evaluated in BALB/c mice and golden Syrian hamsters. The vaccine preparation was tested with or without adjuvants. Adjuvant Systems AS01B and AS03A were selected and tested for their capacity to elicit high humoral and cellular immune responses to WI-SARS vaccine. We evaluated the effect of vaccine dose and each adjuvant on immunogenicity and efficacy in mice, and the effect of vaccine dose with or without the AS01B adjuvant on the immunogenicity and efficacy in hamsters. Efficacy was evaluated by challenge with wild-type virus at early and late time points (4 and 18 wk post-vaccination). A single dose of vaccine with or without adjuvant was poorly immunogenic in mice; a second dose resulted in a significant boost in antibody levels, even in the absence of adjuvant. The use of adjuvants resulted in higher antibody titers, with the AS01B-adjuvanted vaccine being slightly more immunogenic than the AS03A-adjuvanted vaccine. Two doses of WI-SARS with and without Adjuvant Systems were highly efficacious in mice. In hamsters, two doses of WI-SARS with and without AS01B were immunogenic, and two doses of 2 μg of WI-SARS with and without the adjuvant provided complete protection from early challenge. Although antibody titers had declined in all groups of vaccinated hamsters 18 wk after the second dose, the vaccinated hamsters were still partially protected from wild-type virus challenge. Vaccine with adjuvant provided better protection than non-adjuvanted WI-SARS vaccine at this later time point. Enhanced disease was not observed in the lungs or liver of hamsters following SARS-CoV challenge, regardless of the level of serum neutralizing antibodies. PMID:20883165

Cold-Adapted Influenza and Recombinant Adenovirus Vaccines Induce Cross-Protective Immunity against pH1N1 Challenge in Mice

PubMed Central

Soboleski, Mark R.; Gabbard, Jon D.; Price, Graeme E.; Misplon, Julia A.; Lo, Chia-Yun; Perez, Daniel R.; Ye, Jianqiang; Tompkins, S. Mark; Epstein, Suzanne L.

2011-01-01

Background The rapid spread of the 2009 H1N1 pandemic influenza virus (pH1N1) highlighted problems associated with relying on strain-matched vaccines. A lengthy process of strain identification, manufacture, and testing is required for current strain-matched vaccines and delays vaccine availability. Vaccines inducing immunity to conserved viral proteins could be manufactured and tested in advance and provide cross-protection against novel influenza viruses until strain-matched vaccines became available. Here we test two prototype vaccines for cross-protection against the recent pandemic virus. Methodology/Principal Findings BALB/c and C57BL/6 mice were intranasally immunized with a single dose of cold-adapted (ca) influenza viruses from 1977 or recombinant adenoviruses (rAd) expressing 1934 nucleoprotein (NP) and consensus matrix 2 (M2) (NP+M2-rAd). Antibodies against the M2 ectodomain (M2e) were seen in NP+M2-rAd immunized BALB/c but not C57BL/6 mice, and cross-reacted with pH1N1 M2e. The ca-immunized mice did not develop antibodies against M2e. Despite sequence differences between vaccine and challenge virus NP and M2e epitopes, extensive cross-reactivity of lung T cells with pH1N1 peptides was detected following immunization. Both ca and NP+M2-rAd immunization protected BALB/c and C57BL/6 mice against challenge with a mouse-adapted pH1N1 virus. Conclusion/Significance Cross-protective vaccines such as NP+M2-rAd and ca virus are effective against pH1N1 challenge within 3 weeks of immunization. Protection was not dependent on recognition of the highly variable external viral proteins and could be achieved with a single vaccine dose. The rAd vaccine was superior to the ca vaccine by certain measures, justifying continued investigation of this experimental vaccine even though ca vaccine is already available. This study highlights the potential for cross-protective vaccines as a public health option early in an influenza pandemic. PMID:21789196

Aerogenic Vaccination With a Burkholderia mallei Auxotroph Protects Against Aerosol-Initiated Glanders in Mice

DTIC Science & Technology

2005-03-14

Vaccine 23 (2005) 1986–1992 Aerogenic vaccination with a Burkholderia mallei auxotroph protects against aerosol-initiated glanders in mice Ricky L...October 2004 Available online 11 November 2004 Abstract Burkholderia mallei is an obligate mammalian pathogen that causes the zoonotic disease glanders ... Burkholderia mallei , the causative agent of glanders , is gram-negative bacillus. It is a highly adapted parasite of quines and cannot persist in nature

Intradermal Vaccination With Adjuvanted Ebola Virus Soluble Glycoprotein Subunit Vaccine by Microneedle Patches Protects Mice Against Lethal Ebola Virus Challenge.

PubMed

Liu, Ying; Ye, Ling; Lin, Fang; Gomaa, Yasmine; Flyer, David; Carrion, Ricardo; Patterson, Jean L; Prausnitz, Mark R; Smith, Gale; Glenn, Gregory; Wu, Hua; Compans, Richard W; Yang, Chinglai

2018-06-08

In this study, we investigated immune responses induced by purified Ebola virus (EBOV) soluble glycoprotein (sGP) subunit vaccines via intradermal immunization with microneedle (MN) patches in comparison with intramuscular (IM) injection in mice. Our results showed that MN delivery of EBOV sGP was superior to IM injection in eliciting higher levels and longer lasting antibody responses against EBOV sGP and GP antigens. Moreover, sGP-specific immune responses induced by MN or IM immunizations were effectively augmented by formulating sGP with a saponin-based adjuvant, and they were shown to confer complete protection of mice against lethal mouse-adapted EBOV (MA-EBOV) challenge. In comparison, mice that received sGP without adjuvant by MN or IM immunizations succumbed to lethal MA-EBOV challenge. These results show that immunization with EBOV sGP subunit vaccines with adjuvant by MN patches, which have been shown to provide improved safety and thermal stability, is a promising approach to protect against EBOV infection.

Maternal immunization with a DNA vaccine candidate elicits specific passive protection against post-natal Zika virus infection in immunocompetent BALB/c mice.

PubMed

Wang, Ran; Liao, Xianzheng; Fan, Dongying; Wang, Lei; Song, Ji; Feng, Kaihao; Li, Mingyuan; Wang, Peigang; Chen, Hui; An, Jing

2018-06-07

Zika virus (ZIKV) infection is closely associated in the fetus with microcephaly and in the adults with Guillain-Barré syndrome and even male infertility. It is an urgent international priority to develop a safe and effective vaccine that offers protection to both women of childbearing age and their children. In this study, female immunocompetent BALB/c mice were immunized with a DNA-based vaccine candidate, pVAX1-ZME, expressing the prM/E protein of ZIKV, and the immunogenicity for maternal mice and the post-natal protection for suckling mice were evaluated. It was found that administration with three doses of 50 μg pVAX1-ZME via in vivo electroporation induced robust ZIKV-specific cellular and long-term humoral immune responses with high and sustained neutralizing activity in adult mice. Moreover, using a maternal immunization protocol, neutralizing antibodies provided specific passive protection against ZIKV infection in neonatal mice and effectively inhibited the growth delay. This vaccine candidate is expected to be further evaluated in higher animals, and maternal vaccination shows great promise for protecting both women of childbearing age and their offspring against post-natal ZIKV infection. The vaccinated mothers and ZIKV-challenged pups provide key insight into Zika vaccine evaluation in an available fully immunocompetent animal model. Copyright © 2018 Elsevier Ltd. All rights reserved.

Inactivated and live, attenuated influenza vaccines protect mice against influenza:Streptococcus pyogenes super-infections

PubMed Central

Chaussee, Michael S.; Sandbulte, Heather R.; Schuneman, Margaret J.; DePaula, Frank P.; Addengast, Leslie A.; Schlenker, Evelyn H.; Huber, Victor C.

2011-01-01

Mortality associated with influenza virus super-infections is frequently due to secondary bacterial complications. To date, super-infections with Streptococcus pyogenes have been studied less extensively than those associated with S. pneumoniae. This is significant because a vaccine for S. pyogenes is not clinically available, leaving vaccination against influenza virus as our only means for preventing these super-infections. In this study, we directly compared immunity induced by two types of influenza vaccine, either inactivated influenza virus (IIV) or live, attenuated influenza virus (LAIV), for the ability to prevent super-infections. Our data demonstrate that both IIV and LAIV vaccines induce similar levels of serum antibodies, and that LAIV alone induces IgA expression at mucosal surfaces. Upon super-infection, both vaccines have the ability to limit the induction of pro-inflammatory cytokines within the lung, including IFN-γ which has been shown to contribute to mortality in previous models of super-infection. Limiting expression of these pro-inflammatory cytokines within the lungs subsequently limits recruitment of macrophages and neutrophils to pulmonary surfaces, and ultimately protects both IIV- and LAIV-vaccinated mice from mortality. Despite their overall survival, both IIV- and LAIV-vaccinated mice demonstrated levels of bacteria within the lung tissue to levels that are similar to those seen in unvaccinated mice. Thus, influenza virus:bacteria super-infections can be limited by vaccine-induced immunity against influenza virus, but the ability to prevent morbidity is not complete. PMID:21440037

Protection against anthrax and plague by a combined vaccine in mice and rabbits.

PubMed

Ren, Jun; Dong, Dayong; Zhang, Jinlong; Zhang, Jun; Liu, Shuling; Li, Bing; Fu, Ling; Xu, Junjie; Yu, Changming; Hou, Lihua; Li, Jianmin; Chen, Wei

2009-12-09

The protective antigen (PA) of Bacillus anthracis and the Fraction 1 Capsular Antigen (F1 antigen), V antigen of Yersinia pestis have been demonstrated to be potential immunogens and candidate vaccine sub-units against anthrax and plague respectively. In this study, the authors have investigated the antibody responses and the protective efficacy when the antigens were administered separately or in combination intramuscularly formulation adsorbed to an aluminum hydroxide adjuvant. Results show that immunized rF1 + rV and rPA antigen together was as effective as separately for induction of serological antibody response, and these titers were maintained for over 1 year in mice. An isotype analysis of the serum indicates that the co-administration of these antigens did not influence the antigen-specific IgG1/IgG2a ratio which was consistent with a Th2 bias. Furthermore, the combined vaccine comprising the protein antigens rF1 + rV + rPA has been demonstrated to protect mice from subcutaneous challenge with 10(7) colony-forming units (CFU) virulent Y. pestis strain, and to fully protect rabbit against subcutaneous challenge with 1.2x10(5) colony-forming units (CFU) virulent B. anthracis spores. These data show that the protective efficacy was unaffected when the antigens were administered in combination.

A genetically engineered live attenuated vaccine of Coccidioides posadasii protects BALB/c mice against coccidioidomycosis.

PubMed

Xue, Jianmin; Chen, Xia; Selby, Dale; Hung, Chiung-Yu; Yu, Jieh-Juen; Cole, Garry T

2009-08-01

Coccidioidomycosis (also known as San Joaquin Valley fever) is an occupational disease. Workers exposed to outdoor dust which contains spores of the soil-inhabiting fungus have a significantly increased risk of respiratory infection. In addition, people with compromised T-cell immunity, the elderly, and certain racial groups, particularly African-Americans and Filipinos, who live in regions of endemicity in the southwestern United States have an elevated incidence of symptomatic infection caused by inhalation of spores of Coccidioides posadasii or Coccidioides immitis. Recurring epidemics and escalation of medical costs have helped to motivate production of a vaccine against valley fever. The major focus has been the development of a defined, T-cell-reactive, recombinant protein vaccine. However, none of the products described to date have provided full protection to coccidioidal disease-susceptible BALB/c mice. Here we describe the first genetically engineered, live, attenuated vaccine that protects both BALB/c and C57BL/6 mice against coccidioidomycosis. Two chitinase genes (CTS2 and CTS3) were disrupted to yield the attenuated strain, which was unable to endosporulate and was no longer infectious. Vaccinated survivors mounted an immune response characterized by production of both T-helper-1- and T-helper-2-type cytokines. Histology revealed well-formed granulomas and markedly diminished inflammation. Significantly fewer organisms were observed in the lungs of survivors than in those of nonvaccinated mice. Additional investigations are required to further define the nature of the live, attenuated vaccine-induced immunity against Coccidioides infection.

Adjuvanted multi-epitope vaccines protect HLA-A*1101 transgenic mice against Toxoplasma gondii

USDA-ARS?s Scientific Manuscript database

We created and tested multi-epitope DNA or protein vaccines with TLR4 ligand emulsion adjuvant (gluco glucopyranosyl lipid adjuvant in a stable emulsion (GLA-SE)) for their ability to protect against Toxoplasma gondii in HLA transgenic mice. Our constructs each included five of our best down selecte...

Virus-Like Particle Vaccine Protects against 2009 H1N1 Pandemic Influenza Virus in Mice

PubMed Central

Quan, Fu-Shi; Vunnava, Aswani; Compans, Richard W.; Kang, Sang-Moo

2010-01-01

Background The 2009 influenza pandemic and shortages in vaccine supplies worldwide underscore the need for new approaches to develop more effective vaccines. Methodology/Principal Findings We generated influenza virus-like particles (VLPs) containing proteins derived from the A/California/04/2009 virus, and tested their efficacy as a vaccine in mice. A single intramuscular vaccination with VLPs provided complete protection against lethal challenge with the A/California/04/2009 virus and partial protection against A/PR/8/1934 virus, an antigenically distant human isolate. VLP vaccination induced predominant IgG2a antibody responses, high hemagglutination inhibition (HAI) titers, and recall IgG and IgA antibody responses. HAI titers after VLP vaccination were equivalent to those observed after live virus infection. VLP immune sera also showed HAI responses against diverse geographic pandemic isolates. Notably, a low dose of VLPs could provide protection against lethal infection. Conclusion/Significance This study demonstrates that VLP vaccination provides highly effective protection against the 2009 pandemic influenza virus. The results indicate that VLPs can be developed into an effective vaccine, which can be rapidly produced and avoid the need to isolate high growth reassortants for egg-based production. PMID:20161790

Post-exposure vaccination with MP-12 lacking NSs protects mice against lethal Rift Valley fever virus challenge.

PubMed

Gowen, Brian B; Bailey, Kevin W; Scharton, Dionna; Vest, Zachery; Westover, Jonna B; Skirpstunas, Ramona; Ikegami, Tetsuro

2013-05-01

Rift Valley fever virus (RVFV) causes severe disease in humans and livestock. There are currently no approved antivirals or vaccines for the treatment or prevention of RVF disease in humans. A major virulence factor of RVFV is the NSs protein, which inhibits host transcription including the interferon (IFN)-β gene and promotes the degradation of dsRNA-dependent protein kinase, PKR. We analyzed the efficacy of the live-attenuated MP-12 vaccine strain and MP-12 variants that lack the NSs protein as post-exposure vaccinations. Although parental MP-12 failed to elicit a protective effect in mice challenged with wild-type (wt) RVFV by the intranasal route, significant protection was demonstrated by vaccination with MP-12 strains lacking NSs when they were administered at 20-30 min post-exposure. Viremia and virus replication in liver, spleen and brain were also inhibited by post-exposure vaccination with MP-12 lacking NSs. The protective effect was mostly lost when vaccination was delayed 6 or 24 h after intranasal RVFV challenge. When mice were challenged subcutaneously, efficacy of MP-12 lacking NSs was diminished, most likely due to more rapid dissemination of wt RVFV. Our findings suggest that post-exposure vaccination with MP-12 lacking NSs may be developed as a novel post-exposure treatment to prevent RVF. Copyright © 2013 Elsevier B.V. All rights reserved.

T-cell-mediated cross-strain protective immunity elicited by prime-boost vaccination with a live attenuated influenza vaccine.

PubMed

Li, Junwei; Arévalo, Maria T; Chen, Yanping; Chen, Shan; Zeng, Mingtao

2014-10-01

Antigenic drift and shift of influenza viruses require frequent reformulation of influenza vaccines. In addition, seasonal influenza vaccines are often mismatched to the epidemic influenza strains. This stresses the need for a universal influenza vaccine. BALB/c mice were vaccinated with the trivalent live attenuated (LAIV; FluMist) or inactivated (TIV; FluZone) influenza vaccines and challenged with PR8 (H1N1), FM/47 (H1N1), or HK/68 (H3N2) influenza virus. Cytokines and antibody responses were tested by ELISA. Furthermore, different LAIV dosages were applied in BALB/c mice. LAIV vaccinated mice were also depleted of T-cells and challenged with PR8 virus. LAIV induced significant protection against challenge with the non-vaccine strain PR8 influenza virus. Furthermore, protective immunity against PR8 was dose-dependent. Of note, interleukin 2 and interferon gamma cytokine secretion in the lung alveolar fluid were significantly elevated in mice vaccinated with LAIV. Moreover, T-cell depletion of LAIV vaccinated mice compromised protection, indicating that T-cell-mediated immunity is required. In contrast, passive transfer of sera from mice vaccinated with LAIV into naïve mice failed to protect against PR8 challenge. Neutralization assays in vitro confirmed that LAIV did not induce cross-strain neutralizing antibodies against PR8 virus. Finally, we showed that three doses of LAIV also provided protection against challenge with two additional heterologous viruses, FM/47 and HK/68. These results support the potential use of the LAIV as a universal influenza vaccine under a prime-boost vaccination regimen. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Crimean-Congo Hemorrhagic Fever Virus Subunit Vaccines Induce High Levels of Neutralizing Antibodies But No Protection in STAT1 Knockout Mice.

PubMed

Kortekaas, Jeroen; Vloet, Rianka P M; McAuley, Alexander J; Shen, Xiaoli; Bosch, Berend Jan; de Vries, Laura; Moormann, Rob J M; Bente, Dennis A

2015-12-01

Crimean-Congo hemorrhagic fever virus is a tick-borne bunyavirus of the Nairovirus genus that causes hemorrhagic fever in humans with high case fatality. Here, we report the development of subunit vaccines and their efficacy in signal transducer and activator of transcription 1 (STAT1) knockout mice. Ectodomains of the structural glycoproteins Gn and Gc were produced using a Drosophila insect cell-based expression system. A single vaccination of STAT129 mice with adjuvanted Gn or Gc ectodomains induced neutralizing antibody responses, which were boosted by a second vaccination. Despite these antibody responses, mice were not protected from a CCHFV challenge infection. These results suggest that neutralizing antibodies against CCHFV do not correlate with protection of STAT1 knockout mice.

Live, Attenuated Influenza A H5N1 Candidate Vaccines Provide Broad Cross-Protection in Mice and Ferrets

PubMed Central

Mills, Kimberly L; Jin, Hong; Duke, Greg; Lu, Bin; Luke, Catherine J; Murphy, Brian; Swayne, David E; Kemble, George; Subbarao, Kanta

2006-01-01

Background Recent outbreaks of highly pathogenic influenza A H5N1 viruses in humans and avian species that began in Asia and have spread to other continents underscore an urgent need to develop vaccines that would protect the human population in the event of a pandemic. Methods and Findings Live, attenuated candidate vaccines possessing genes encoding a modified H5 hemagglutinin (HA) and a wild-type (wt) N1 neuraminidase from influenza A H5N1 viruses isolated in Hong Kong and Vietnam in 1997, 2003, and 2004, and remaining gene segments derived from the cold-adapted (ca) influenza A vaccine donor strain, influenza A/Ann Arbor/6/60 ca (H2N2), were generated by reverse genetics. The H5N1 ca vaccine viruses required trypsin for efficient growth in vitro, as predicted by the modification engineered in the gene encoding the HA, and possessed the temperature-sensitive and attenuation phenotypes specified by the internal protein genes of the ca vaccine donor strain. More importantly, the candidate vaccines were immunogenic in mice. Four weeks after receiving a single dose of 106 50% tissue culture infectious doses of intranasally administered vaccines, mice were fully protected from lethality following challenge with homologous and antigenically distinct heterologous wt H5N1 viruses from different genetic sublineages (clades 1, 2, and 3) that were isolated in Asia between 1997 and 2005. Four weeks after receiving two doses of the vaccines, mice and ferrets were fully protected against pulmonary replication of homologous and heterologous wt H5N1 viruses. Conclusions The promising findings in these preclinical studies of safety, immunogenicity, and efficacy of the H5N1 ca vaccines against antigenically diverse H5N1 vaccines provide support for their careful evaluation in Phase 1 clinical trials in humans. PMID:16968127

A Safe Vaccine (DV-STM-07) against Salmonella Infection Prevents Abortion and Confers Protective Immunity to the Pregnant and New Born Mice

PubMed Central

Negi, Vidya Devi; Nagarajan, Arvindhan G.; Chakravortty, Dipshikha

2010-01-01

Pregnancy is a transient immuno-compromised condition which has evolved to avoid the immune rejection of the fetus by the maternal immune system. The altered immune response of the pregnant female leads to increased susceptibility to invading pathogens, resulting in abortion and congenital defects of the fetus and a subnormal response to vaccination. Active vaccination during pregnancy may lead to abortion induced by heightened cell mediated immune response. In this study, we have administered the highly attenuated vaccine strain ΔpmrG-HM-D (DV-STM-07) in female mice before the onset of pregnancy and followed the immune reaction against challenge with virulent S. Typhimurium in pregnant mice. Here we demonstrate that DV-STM-07 vaccine gives protection against Salmonella in pregnant mice and also prevents Salmonella induced abortion. This protection is conferred by directing the immune response towards Th2 activation and Th1 suppression. The low Th1 response prevents abortion. The use of live attenuated vaccine just before pregnancy carries the risk of transmission to the fetus. We have shown that this vaccine is safe as the vaccine strain is quickly eliminated from the mother and is not transmitted to the fetus. This vaccine also confers immunity to the new born mice of vaccinated mothers. Since there is no evidence of the vaccine candidate reaching the new born mice, we hypothesize that it may be due to trans-colostral transfer of protective anti-Salmonella antibodies. These results suggest that our vaccine DV-STM-07 can be very useful in preventing abortion in the pregnant individuals and confer immunity to the new born. Since there are no such vaccine candidates which can be given to the new born and to the pregnant women, this vaccine holds a very bright future to combat Salmonella induced pregnancy loss. PMID:20161765

A Burkholderia pseudomallei Outer Membrane Vesicle Vaccine Provides Cross Protection against Inhalational Glanders in Mice and Non-Human Primates.

PubMed

Baker, Sarah M; Davitt, Christopher J H; Motyka, Natalya; Kikendall, Nicole L; Russell-Lodrigue, Kasi; Roy, Chad J; Morici, Lisa A

2017-12-09

Burkholderia mallei is a Gram-negative, non-motile, facultative intracellular bacillus and the causative agent of glanders, a highly contagious zoonotic disease. B. mallei is naturally resistant to multiple antibiotics and there is concern for its potential use as a bioweapon, making the development of a vaccine against B. mallei of critical importance. We have previously demonstrated that immunization with multivalent outer membrane vesicles (OMV) derived from B. pseudomallei provide significant protection against pneumonic melioidosis. Given that many virulence determinants are highly conserved between the two species, we sought to determine if the B. pseudomallei OMV vaccine could cross-protect against B. mallei . We immunized C57Bl/6 mice and rhesus macaques with B. pseudomallei OMVs and subsequently challenged animals with aerosolized B. mallei . Immunization with B. pseudomallei OMVs significantly protected mice against B. mallei and the protection observed was comparable to that achieved with a live attenuated vaccine. OMV immunization induced the production of B.mallei- specific serum IgG and a mixed Th1/Th17 CD4 and CD8 T cell response in mice. Additionally, immunization of rhesus macaques with B. pseudomallei OMVs provided protection against glanders and induced B.mallei -specific serum IgG in non-human primates. These results demonstrate the ability of the multivalent OMV vaccine platform to elicit cross-protection against closely-related intracellular pathogens and to induce robust humoral and cellular immune responses against shared protective antigens.

A Burkholderia pseudomallei Outer Membrane Vesicle Vaccine Provides Cross Protection against Inhalational Glanders in Mice and Non-Human Primates

PubMed Central

Davitt, Christopher J. H.; Motyka, Natalya; Kikendall, Nicole L.; Roy, Chad J.

2017-01-01

Burkholderia mallei is a Gram-negative, non-motile, facultative intracellular bacillus and the causative agent of glanders, a highly contagious zoonotic disease. B. mallei is naturally resistant to multiple antibiotics and there is concern for its potential use as a bioweapon, making the development of a vaccine against B. mallei of critical importance. We have previously demonstrated that immunization with multivalent outer membrane vesicles (OMV) derived from B. pseudomallei provide significant protection against pneumonic melioidosis. Given that many virulence determinants are highly conserved between the two species, we sought to determine if the B. pseudomallei OMV vaccine could cross-protect against B. mallei. We immunized C57Bl/6 mice and rhesus macaques with B. pseudomallei OMVs and subsequently challenged animals with aerosolized B. mallei. Immunization with B. pseudomallei OMVs significantly protected mice against B. mallei and the protection observed was comparable to that achieved with a live attenuated vaccine. OMV immunization induced the production of B.mallei-specific serum IgG and a mixed Th1/Th17 CD4 and CD8 T cell response in mice. Additionally, immunization of rhesus macaques with B. pseudomallei OMVs provided protection against glanders and induced B.mallei-specific serum IgG in non-human primates. These results demonstrate the ability of the multivalent OMV vaccine platform to elicit cross-protection against closely-related intracellular pathogens and to induce robust humoral and cellular immune responses against shared protective antigens. PMID:29232837

Characterization of cross protection of Swine-Origin Influenza Virus (S-OIV) H1N1 and reassortant H5N1 influenza vaccine in BALB/c mice given a single-dose vaccination

PubMed Central

2013-01-01

Background Influenza virus has antigen drift and antigen shift effect, vaccination with some influenza vaccine might not induce sufficient immunity for host to the threat of other influenza virus strains. S-OIV H1N1 and H5N1 influenza vaccines in single-dose immunization were evaluated in mice for cross protection to the challenge of A/California/7/2009 H1N1 or NIBRG-14 H5N1 virus. Results Both H1N1 and H5N1 induced significant homologous IgG, HAI, and microneutralization antibody responses in the mice, while only vaccines plus adjuvant produced significant heterogeneous IgG and HAI antibody responses. Both alum and MPLA adjuvants significantly reduced the S-OIV H1N1 vaccine dose required to elicit protective HAI antibody titers from 0.05 μg to 0.001 μg. Vaccines alone did not protect mice from challenge with heterogeneous influenza virus, while H5N1 vaccine plus alum and MPLA adjuvants did. Mouse body weight loss was also less significant in the presence of adjuvant than in the vaccine without adjuvant. Furthermore, both H1N1 and H5N1 lung viral titers of immunized mice were significantly reduced post challenge with homologous viruses. Conclusion Only in the presence of MPLA adjuvant could the H5N1 vaccine significantly reduce mouse lung viral titers post H1N1 virus challenge, and not vice versa. MPLA adjuvant induced cross protection with a single dose vaccination to the challenge of heterogeneous influenza virus in mice. Lung viral titer seemed to be a better indicator compared to IgG, neutralization antibody, and HAI titer to predict survival of mice infected with influenza virus. PMID:23517052

Heat-stable oral alga-based vaccine protects mice from Staphylococcus aureus infection.

PubMed

Dreesen, Imke A J; Charpin-El Hamri, Ghislaine; Fussenegger, Martin

2010-02-01

While 15 million deaths per year are caused by communicable pathogens worldwide, health care authorities emphasize the considerable impact of poverty on the incidence of infectious diseases. The emergence of antigen-expressing plant tissues (e.g. rice, tomato, potato) has indicated the potential of land plants for low-cost vaccines in oral immunization programs. In this study, we engineered the chloroplasts of the unicellular green alga Chlamydomonas reinhardtii for the stable expression of the D2 fibronectin-binding domain of Staphylococcus aureus fused with the cholera toxin B subunit (CTB), under the control of rbcL UTRs. Analysis of sera and faeces of mice, fed for 5 weeks with transgenic algae grown in confined Wave Bioreactor, revealed the induction of specific mucosal and systemic immune responses. Algae-based vaccination significantly reduced the pathogen load in the spleen and the intestine of treated mice and protected 80% of them against lethal doses of S. aureus. Importantly, the alga vaccine was stable for more than 1.5 years at room temperature. These results indicate that C. reinhardtii may play an important role in molecular pharming, as it combines the beneficial features of land plant vaccines, while offering unmatched ease of growth compared to other members of the plant kingdom. Copyright 2010 Elsevier B.V. All rights reserved.

CD4+ T Cells Mediate Aspergillosis Vaccine Protection.

PubMed

Diaz-Arevalo, Diana; Kalkum, Markus

2017-01-01

Adaptive effector CD4 + T cells play essential roles in the defense against fungal infections, especially against invasive aspergillosis (IA). Such protective CD4 + T cells can be generated through immunization with specialized antifungal vaccines, as has been demonstrated for pulmonary Aspergillus fumigatus infections in mouse experiments. Adaptive transfer of fungal antigen-specific CD4 + T cells conferred protection onto non-immunized naive mice, an experimental approach that could potentially become a future treatment option for immunosuppressed IA patients, focusing on the ultimate goal to improve their otherwise dim chances for survival. Here, we describe the different techniques to analyze CD4 + T cell immune responses after immunization with a recombinant fungal protein. We present three major methods that are used to analyze the role of CD4 + T cells in protection against A. fumigatus challenge. They include (1) transplantation of CD4 + T cells from vaccinated mice into immunosuppressed naive mice, observing increasing protection of the cell recipients, (2) depletion of CD4 + T cells from vaccinated mice, which abolishes vaccine protection, and (3) T cell proliferation studies following stimulation with overlapping synthetic peptides or an intact protein vaccine. The latter can be used to validate immunization status and to identify protective T cell epitopes in vaccine antigens. In the methods detailed here, we used versions of the well-studied Asp f3 protein expressed in a bacterial host, either as the intact full length protein or its N-terminally truncated version, comprised of residues 15-168. However, these methods are generally applicable and can well be adapted to study other protein-based subunit vaccines.

Vaccination with Recombinant Cryptococcus Proteins in Glucan Particles Protects Mice against Cryptococcosis in a Manner Dependent upon Mouse Strain and Cryptococcal Species

PubMed Central

Lee, Chrono K.; Huang, Haibin; Hester, Maureen M.; Liu, Jianhua; Luckie, Bridget A.; Torres Santana, Melanie A.; Mirza, Zeynep; Khoshkenar, Payam; Abraham, Ambily; Shen, Zu T.; Lodge, Jennifer K.; Akalin, Ali; Homan, Jane; Ostroff, Gary R.

2017-01-01

ABSTRACT Development of a vaccine to protect against cryptococcosis is a priority given the enormous global burden of disease in at-risk individuals. Using glucan particles (GPs) as a delivery system, we previously demonstrated that mice vaccinated with crude Cryptococcus-derived alkaline extracts were protected against lethal challenge with Cryptococcus neoformans and Cryptococcus gattii. The goal of the present study was to identify protective protein antigens that could be used in a subunit vaccine. Using biased and unbiased approaches, six candidate antigens (Cda1, Cda2, Cda3, Fpd1, MP88, and Sod1) were selected, recombinantly expressed in Escherichia coli, purified, and loaded into GPs. Three mouse strains (C57BL/6, BALB/c, and DR4) were then vaccinated with the antigen-laden GPs, following which they received a pulmonary challenge with virulent C. neoformans and C. gattii strains. Four candidate vaccines (GP-Cda1, GP-Cda2, GP-Cda3, and GP-Sod1) afforded a significant survival advantage in at least one mouse model; some vaccine combinations provided added protection over that seen with either antigen alone. Vaccine-mediated protection against C. neoformans did not necessarily predict protection against C. gattii. Vaccinated mice developed pulmonary inflammatory responses that effectively contained the infection; many surviving mice developed sterilizing immunity. Predicted T helper cell epitopes differed between mouse strains and in the degree to which they matched epitopes predicted in humans. Thus, we have discovered cryptococcal proteins that make promising candidate vaccine antigens. Protection varied depending on the mouse strain and cryptococcal species, suggesting that a successful human subunit vaccine will need to contain multiple antigens, including ones that are species specific. PMID:29184017

Intranasal adenovirus-vectored vaccine for induction of long-lasting humoral immunity-mediated broad protection against influenza in mice.

PubMed

Kim, Eun Hye; Park, Hae-Jung; Han, Gye-Yeong; Song, Man-Ki; Pereboev, Alexander; Hong, Jeong S; Chang, Jun; Byun, Young-Ho; Seong, Baik Lin; Nguyen, Huan H

2014-09-01

Influenza vaccines aimed at inducing antibody (Ab) responses against viral surface hemagglutinin (HA) and neuraminidase (NA) provide sterile immunity to infection with the same subtypes. Vaccines targeting viral conserved determinants shared by the influenza A viruses (IAV) offer heterosubtypic immunity (HSI), a broad protection against different subtypes. We proposed that vaccines targeting both HA and the conserved ectodomain of matrix protein 2 (M2e) would provide protection against infection with the same subtype and also HSI against other subtypes. We report here that single intranasal immunization with a recombinant adenovirus (rAd) vector encoding both HA of H5 virus and M2e (rAdH5/M2e) induced significant HA- and M2e-specific Ab responses, along with protection against heterosubtypic challenge in mice. The protection is superior compared to that induced by rAd vector encoding either HA (rAdH5), or M2e (rAdM2e). While protection against homotypic H5 virus is primarily mediated by virus-neutralizing Abs, the cross-protection is associated with Abs directed to conserved stalk HA and M2e that seem to have an additive effect. Consistently, adoptive transfer of antisera induced by rAdH5/M2e provided the best protection against heterosubtypic challenge compared to that provided by antisera derived from mice immunized with rAdH5 or rAdM2e. These results support the development of rAd-vectored vaccines encoding both H5 and M2e as universal vaccines against different IAV subtypes. Current licensed influenza vaccines provide protection limited to the infection with same virus strains; therefore, the composition of influenza vaccines has to be revised every year. We have developed a new universal influenza vaccine that is highly efficient in induction of long-lasting cross-protection against different influenza virus strains. The cross-protection is associated with a high level of vaccine-induced antibodies against the conserved stalk domain of influenza virus

Edible vaccine protects mice against Escherichia coli heat-labile enterotoxin (LT): potatoes expressing a synthetic LT-B gene.

PubMed

Mason, H S; Haq, T A; Clements, J D; Arntzen, C J

1998-08-01

The authors have designed and constructed a plant-optimize synthetic gene encoding the Escherichia coli heat-labile enterotoxin B subunit (LT-B), for use in transgenic plants as an edible vaccine against enterotoxigenic E. coli. Expression of the synthetic LT-B gene in potato plants under the control of a constitutive promoter yielded increased accumulation of LT-B in leaves and tubers, as compared to the bacterial LT-B gene. The plant-derived LT-B assembled into native pentameric structures as evidenced by its ability to bind ganglioside. The authors demonstrated immunogenicity by feeding mice the raw tubers and comparing the anti-LT-B serum IgG and faecal IgA to that produced in mice gavaged with bacterial LT-B. Mice were fed three weekly doses of 5 g tuber tissue containing either 20 or 50 micrograms LT-B, or gavaged weekly with 5 micrograms of LT-B from recombinant E. coli. One week after the third dose, mice immunized with potato LT-B had higher levels of serum and mucosal anti-LT-B than those gavaged with bacterial LT-B. Mice were challenged by oral administration of 25 micrograms LT, and protection assessed by comparing the gut/carcass mass ratios. Although none of the mice were completely protected, the higher dose potato vaccine compared favourably with the bacterial vaccine. These findings show that an edible vaccine against E. coli LT-B is feasible.

Multiagent vaccines vectored by Venezuelan equine encephalitis virus replicon elicits immune responses to Marburg virus and protection against anthrax and botulinum neurotoxin in mice.

PubMed

Lee, John S; Groebner, Jennifer L; Hadjipanayis, Angela G; Negley, Diane L; Schmaljohn, Alan L; Welkos, Susan L; Smith, Leonard A; Smith, Jonathan F

2006-11-17

The development of multiagent vaccines offers the advantage of eliciting protection against multiple diseases with minimal inoculations over a shorter time span. We report here the results of using formulations of individual Venezuelan equine encephalitis (VEE) virus replicon-vectored vaccines against a bacterial disease, anthrax; a viral disease, Marburg fever; and against a toxin-mediated disease, botulism. The individual VEE replicon particles (VRP) expressed mature 83-kDa protective antigen (MAT-PA) from Bacillus anthracis, the glycoprotein (GP) from Marburg virus (MBGV), or the H(C) fragment from botulinum neurotoxin (BoNT H(C)). CBA/J mice inoculated with a mixture of VRP expressing BoNT H(C) serotype C (BoNT/C H(C)) and MAT-PA were 80% protected from a B. anthracis (Sterne strain) challenge and then 100% protected from a sequential BoNT/C challenge. Swiss mice inoculated with individual VRP or with mixtures of VRP vaccines expressing BoNT H(C) serotype A (BoNT/A H(C)), MAT-PA, and MBGV-GP produced antibody responses specific to the corresponding replicon-expressed protein. Combination of the different VRP vaccines did not diminish the antibody responses measured for Swiss mice inoculated with formulations of two or three VRP vaccines as compared to mice that received only one VRP vaccine. Swiss mice inoculated with VRP expressing BoNT/A H(C) alone or in combination with VRP expressing MAT-PA and MBGV GP, were completely protected from a BoNT/A challenge. These studies demonstrate the utility of combining individual VRP vaccines into multiagent formulations for eliciting protective immune responses to various types of diseases.

Protective immunity against influenza in HLA-A2 transgenic mice by modified vaccinia virus Ankara vectored vaccines containing internal influenza proteins.

PubMed

Di Mario, Giuseppina; Sciaraffia, Ester; Facchini, Marzia; Gubinelli, Francesco; Soprana, Elisa; Panigada, Maddalena; Bernasconi, Valentina; Garulli, Bruno; Siccardi, Antonio; Donatelli, Isabella; Castrucci, Maria R

2017-03-01

The emergence of novel strains of influenza A viruses with hemagglutinins (HAs) that are antigenically distinct from those circulating in humans, and thus have pandemic potential, pose concerns and call for the development of more broadly protective influenza vaccines. In the present study, modified vaccinia virus Ankara (MVA) encoding internal influenza antigens were evaluated for their immunogenicity and ability to protect HLA-A2.1 transgenic (AAD) mice from infection with influenza viruses. MVAs expressing NP (MVA-NP), M1 (MVA-M1) or polymerase PB1 (MVA-PB1) of A/California/4/09 (CA/09) virus were generated and used to immunize AAD mice. Antibodies and CD8+T cell responses were assessed by ELISA and ELISPOT, respectively, and challenge experiments were performed by infecting vaccinated mice with CA/09 virus. CD8+T cells specific to immunodominant and subdominant epitopes on the internal influenza proteins were elicited by MVA-based vectors in AAD mice, whereas influenza-specific antibodies were detected only in MVA-NP-immunized mice. Both M1- and NP-based MVA vaccines, regardless of whether they were applied individually or in combination, conferred protection against lethal influenza virus challenge. Our data further emphasize the promising potential of MVA vector expressing internal antigens toward the development of a universal influenza vaccine.

Safety, immunogenicity and protective efficacy in mice of a new cell-cultured Lister smallpox vaccine candidate.

PubMed

Ferrier-Rembert, Audrey; Drillien, Robert; Meignier, Bernard; Garin, Daniel; Crance, Jean-Marc

2007-11-28

It is now difficult to manufacture the first-generation smallpox vaccine, as the process could not comply with current safety and manufacturing regulations. In this study, a candidate non-clonal second-generation smallpox vaccine developed by Sanofi-Pasteur from the Lister strain has been assessed using a cowpox virus challenge in mice. We have observed similar safety, immunogenicity and protection (from disease and death) after a short or long interval following vaccination, as well as similar virus clearance post-challenge, with the second-generation smallpox vaccine candidate as compared to the traditional vaccine used as a benchmark.

Effective Protection Induced by a Monovalent DNA Vaccine against Dengue Virus (DV) Serotype 1 and a Bivalent DNA Vaccine against DV1 and DV2 in Mice.

PubMed

Zheng, Xiaoyan; Chen, Hui; Wang, Ran; Fan, Dongying; Feng, Kaihao; Gao, Na; An, Jing

2017-01-01

Dengue virus (DV) is the causal pathogen of dengue fever, which is one of the most rapidly spread mosquito-borne disease worldwide and has become a severe public health problem. Currently, there is no specific treatment for dengue; thus, a vaccine would be an effective countermeasure to reduce the morbidity and mortality. Although, the chimeric Yellow fever dengue tetravalent vaccine has been approved in some countries, it is still necessary to develop safer, more effective, and less costly vaccines. In this study, a DNA vaccine candidate pVAX1-D1ME expressing the prME protein of DV1 was inoculated in BALB/c mice via intramuscular injection or electroporation, and the immunogenicity and protection were evaluated. Compared with traditional intramuscular injection, administration with 50 μg pVAX1-D1ME via electroporation with three immunizations induced persistent humoral and cellular immune responses and effectively protected mice against lethal DV1 challenge. In addition, immunization with a bivalent vaccine consisting of pVAX1-D1ME and pVAX1-D2ME via electroporation generated a balanced IgG response and neutralizing antibodies against DV1 and DV2 and could protect mice from lethal challenge with DV1 and DV2. This study sheds new light on developing a dengue tetravalent DNA vaccine.

Post-exposure Treatment with Anti-rabies VHH and Vaccine Significantly Improves Protection of Mice from Lethal Rabies Infection

PubMed Central

Terryn, Sanne; Francart, Aurélie; Rommelaere, Heidi; Stortelers, Catelijne; Van Gucht, Steven

2016-01-01

Post-exposure prophylaxis (PEP) against rabies infection consists of a combination of passive immunisation with plasma-derived human or equine immune globulins and active immunisation with vaccine delivered shortly after exposure. Since anti-rabies immune globulins are expensive and scarce, there is a need for cheaper alternatives that can be produced more consistently. Previously, we generated potent virus-neutralising VHH, also called Nanobodies, against the rabies glycoprotein that are effectively preventing lethal disease in an in vivo mouse model. The VHH domain is the smallest antigen-binding functional fragment of camelid heavy chain-only antibodies that can be manufactured in microbial expression systems. In the current study we evaluated the efficacy of half-life extended anti-rabies VHH in combination with vaccine for PEP in an intranasal rabies infection model in mice. The PEP combination therapy of systemic anti-rabies VHH and intramuscular vaccine significantly delayed the onset of disease compared to treatment with anti-rabies VHH alone, prolonged median survival time (35 versus 14 days) and decreased mortality (60% versus 19% survival rate), when treated 24 hours after rabies virus challenge. Vaccine alone was unable to rescue mice from lethal disease. As reported also for immune globulins, some interference of anti-rabies VHH with the antigenicity of the vaccine was observed, but this did not impede the synergistic effect. Post exposure treatment with vaccine and human anti-rabies immune globulins was unable to protect mice from lethal challenge. Anti-rabies VHH and vaccine act synergistically to protect mice after rabies virus exposure, which further validates the possible use of anti-rabies VHH for rabies PEP. PMID:27483431

DNA vaccine expressing herpes simplex virus 1 glycoprotein C and D protects mice against herpes simplex keratitis

PubMed Central

Dong, Li-Li; Tang, Ru; Zhai, Yu-Jia; Malla, Tejsu; Hu, Kai

2017-01-01

AIM To investigate whether DNA vaccine encoding herpes simplex virus 1 (HSV-1) glycoprotein C (gC) and glycoprotein D (gD) will achieve better protective effect against herpes simplex keratitis (HSK) than DNA vaccine encoding gD alone. METHODS DNA vaccine expressing gD or gC combined gD (gD.gC) were constructed and carried by chitosan nanoparticle. The expression of fusion protein gD and gC were detected in DNA/nanoparticle transfected 293T cells by Western-blot. For immunization, mice were inoculated with DNA/nanoparticle for 3 times with 2wk interval, and two weeks after the final immunization, the specific immune responses and clinical degrees of primary HSK were evaluated. RESULTS Fusion protein gD.gC could be expressed successfully in cultured 293T cells. And, pRSC-gC.gD-IL21 DNA/chitosan nanoparticle could effectively elicit strongest humoral and cellular immune response in primary HSK mice evidenced by higher levels of specific neutralizing antibody and sIgA production, enhanced cytotoxicities of splenocytes and nature killer cells (NK), when compared with those of gD alone or mocked vaccine immunized mice. As a result, gC-based vaccine immunized mice showed least HSK disease. CONCLUSION gC-based DNA vaccine could effectively prevent the progress of primary HSK, suggesting that this DNA vaccine could be a promising vaccine for HSK treatment in the future. PMID:29181304

A DNA Vaccine That Targets Hemagglutinin to Antigen-Presenting Cells Protects Mice against H7 Influenza

PubMed Central

Andersen, Tor Kristian; Zhou, Fan; Cox, Rebecca; Bogen, Bjarne

2017-01-01

ABSTRACT Zoonotic influenza H7 viral infections have a case fatality rate of about 40%. Currently, no or limited human to human spread has occurred, but we may be facing a severe pandemic threat if the virus acquires the ability to transmit between humans. Novel vaccines that can be rapidly produced for global distribution are urgently needed, and DNA vaccines may be the only type of vaccine that allows for the speed necessary to quench an emerging pandemic. Here, we constructed DNA vaccines encoding the hemagglutinin (HA) from influenza A/chicken/Italy/13474/99 (H7N1). In order to increase the efficacy of DNA vaccination, HA was targeted to either major histocompatibility complex class II molecules or chemokine receptors 1, 3, and 5 (CCR1/3/5) that are expressed on antigen-presenting cells (APC). A single DNA vaccination with APC-targeted HA significantly increased antibody levels in sera compared to nontargeted control vaccines. The antibodies were confirmed neutralizing in an H7 pseudotype-based neutralization assay. Furthermore, the APC-targeted vaccines increased the levels of antigen-specific cytotoxic T cells, and a single DNA vaccination could confer protection against a lethal challenge with influenza A/turkey/Italy/3889/1999 (H7N1) in mice. In conclusion, we have developed a vaccine that rapidly could contribute protection against a pandemic threat from avian influenza. IMPORTANCE Highly pathogenic avian influenza H7 constitute a pandemic threat that can cause severe illness and death in infected individuals. Vaccination is the main method of prophylaxis against influenza, but current vaccine strategies fall short in a pandemic situation due to a prolonged production time and insufficient production capabilities. In contrast, a DNA vaccine can be rapidly produced and deployed to prevent the potential escalation of a highly pathogenic influenza pandemic. We here demonstrate that a single DNA delivery of hemagglutinin from an H7 influenza could mediate full

Thermostable Cross-Protective Subunit Vaccine against Brucella Species

PubMed Central

Barabé, Nicole D.; Grigat, Michelle L.; Lee, William E.; Poirier, Robert T.; Jager, Scott J.; Berger, Bradley J.

2014-01-01

A subunit vaccine candidate was produced from Brucella suis 145 (biovar 4; expressing both the A antigen of Brucella abortus and the M antigen of Brucella melitensis). The preparation consisted mostly of polysaccharide (PS; >90% [wt/wt]; both cell-associated PS and exo-PS were combined) and a small amount of protein (1 to 3%) with no apparent nucleic acids. Vaccinated mice were protected (these had a statistically significant reduction in bacterial colonization compared to that of unvaccinated controls) when challenged with representative strains of three Brucella species most pathogenic for humans, i.e., B. abortus, B. melitensis, and B. suis. As little as 1 ng of the vaccine, without added adjuvant, protected mice against B. suis 145 infection (5 × 105 CFU), and a single injection of 1 μg of this subunit vaccine protected mice from B. suis 145 challenge for at least 14 months. A single immunization induced a serum IgG response to Brucella antigens that remained elevated for up to 9 weeks. The use of heat (i.e., boiling-water bath, autoclaving) in the vaccine preparation showed that it was thermostable. This method also ensured safety and security. The vaccine produced was immunogenic and highly protective against multiple strains of Brucella and represents a promising candidate for further evaluation. PMID:25320267

Thermostable cross-protective subunit vaccine against Brucella species.

PubMed

Cherwonogrodzky, John W; Barabé, Nicole D; Grigat, Michelle L; Lee, William E; Poirier, Robert T; Jager, Scott J; Berger, Bradley J

2014-12-01

A subunit vaccine candidate was produced from Brucella suis 145 (biovar 4; expressing both the A antigen of Brucella abortus and the M antigen of Brucella melitensis). The preparation consisted mostly of polysaccharide (PS; >90% [wt/wt]; both cell-associated PS and exo-PS were combined) and a small amount of protein (1 to 3%) with no apparent nucleic acids. Vaccinated mice were protected (these had a statistically significant reduction in bacterial colonization compared to that of unvaccinated controls) when challenged with representative strains of three Brucella species most pathogenic for humans, i.e., B. abortus, B. melitensis, and B. suis. As little as 1 ng of the vaccine, without added adjuvant, protected mice against B. suis 145 infection (5 × 10(5) CFU), and a single injection of 1 μg of this subunit vaccine protected mice from B. suis 145 challenge for at least 14 months. A single immunization induced a serum IgG response to Brucella antigens that remained elevated for up to 9 weeks. The use of heat (i.e., boiling-water bath, autoclaving) in the vaccine preparation showed that it was thermostable. This method also ensured safety and security. The vaccine produced was immunogenic and highly protective against multiple strains of Brucella and represents a promising candidate for further evaluation. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Induction of Protective Immune Responses Against Schistosomiasis haematobium in Hamsters and Mice Using Cysteine Peptidase-Based Vaccine

PubMed Central

Tallima, Hatem; Dalton, John P.; El Ridi, Rashika

2015-01-01

One of the major lessons we learned from the radiation-attenuated cercariae vaccine studies is that protective immunity against schistosomiasis is dependent on the induction of T helper (Th)1-/Th2-related immune responses. Since most schistosome larval and adult-worm-derived molecules used for vaccination uniformly induce a polarized Th1 response, it was essential to include a type 2 immune response-inducing molecule, such as cysteine peptidases, in the vaccine formula. Here, we demonstrate that a single subcutaneous injection of Syrian hamsters with 200 μg active papain, 1 h before percutaneous exposure to 150 cercariae of Schistosoma haematobium, led to highly significant (P < 0.005) reduction of >50% in worm burden and worm egg counts in intestine. Immunization of hamsters with 20 μg recombinant glyceraldehyde 3-phosphate dehydrogenase (rSG3PDH) and 20 μg 2-cys peroxiredoxin-derived peptide in a multiple antigen peptide construct (PRX MAP) together with papain (20 μg/hamster), as adjuvant led to considerable (64%) protection against challenge S. haematobium infection, similar to the levels reported with irradiated cercariae. Cysteine peptidases-based vaccination was also effective in protecting outbred mice against a percutaneous challenge infection with S. haematobium cercariae. In two experiments, a mixture of Schistosoma mansoni cathepsin B1 (SmCB1) and Fasciola hepatica cathepsin L1 (FhCL1) led to highly significant (P < 0.005) reduction of 70% in challenge S. haematobium worm burden and 60% reduction in liver egg counts. Mice vaccinated with SmCB1/FhCL1/rSG3PDH mixture and challenged with S. haematobium cercariae 3 weeks after the second immunization displayed highly significant (P < 0.005) reduction of 72% in challenge worm burden and no eggs in liver of 8–10 mice/group, as compared to unimmunized mice, associated with production of a mixture of type 1- and type 2-related cytokines and antibody responses. PMID:25852696

Combination of Pneumococcal Surface Protein A (PspA) with Whole Cell Pertussis Vaccine Increases Protection Against Pneumococcal Challenge in Mice

PubMed Central

Ferreira, Daniela M.; Moreno, Adriana T.; Ferreira, Patricia C. D.; Lima, Fernanda A.; Santos, Fernanda L.; Sakauchi, Maria Aparecida; Takata, Célia S.; Higashi, Hisako G.; Raw, Isaías; Kubrusly, Flavia S.; Ho, Paulo L.

2010-01-01

Streptococcus pneumoniae is the leading cause of respiratory acute infections around the world. In Latin America, approximately 20,000 children under 5 years of age die of pneumococcal diseases annually. Pneumococcal surface protein A (PspA) is among the best-characterized pneumococcal antigens that confer protection in animal models of pneumococcal infections and, as such, is a good alternative for the currently available conjugated vaccines. Efficient immune responses directed to PspA in animal models have already been described. Nevertheless, few low cost adjuvants for a subunit pneumococcal vaccine have been proposed to date. Here, we have tested the adjuvant properties of the whole cell Bordetella pertussis vaccine (wP) that is currently part of the DTP (diphtheria-tetanus-pertussis) vaccine administrated to children in several countries, as an adjuvant to PspA. Nasal immunization of BALB/c mice with a combination of PspA5 and wP or wPlow – a new generation vaccine that contains low levels of B. pertussis LPS – conferred protection against a respiratory lethal challenge with S. pneumoniae. Both PspA5-wP and PspA5-wPlow vaccines induced high levels of systemic and mucosal antibodies against PspA5, with similar profile, indicating no essential requirement for B. pertussis LPS in the adjuvant properties of wP. Accordingly, nasal immunization of C3H/HeJ mice with PspA5-wP conferred protection against the pneumococcal challenge, thus ruling out a role for TLR4 responses in the adjuvant activity and the protection mechanisms triggered by the vaccines. The high levels of anti-PspA5 antibodies correlated with increased cross-reactivity against PspAs from different clades and also reflected in cross-protection. In addition, passive immunization experiments indicated that antibodies played an important role in protection in this model. Finally, subcutaneous immunization with a combination of PspA5 with DTPlow protected mice against challenge with two different

Transgenic Parasites Stably Expressing Full-Length Plasmodium falciparum Circumsporozoite Protein as a Model for Vaccine Down-Selection in Mice Using Sterile Protection as an Endpoint

PubMed Central

Porter, Michael D.; Nicki, Jennifer; Pool, Christopher D.; DeBot, Margot; Illam, Ratish M.; Brando, Clara; Bozick, Brooke; De La Vega, Patricia; Angra, Divya; Spaccapelo, Roberta; Crisanti, Andrea; Murphy, Jittawadee R.; Bennett, Jason W.; Schwenk, Robert J.; Ockenhouse, Christian F.

2013-01-01

Circumsporozoite protein (CSP) of Plasmodium falciparum is a protective human malaria vaccine candidate. There is an urgent need for models that can rapidly down-select novel CSP-based vaccine candidates. In the present study, the mouse-mosquito transmission cycle of a transgenic Plasmodium berghei malaria parasite stably expressing a functional full-length P. falciparum CSP was optimized to consistently produce infective sporozoites for protection studies. A minimal sporozoite challenge dose was established, and protection was defined as the absence of blood-stage parasites 14 days after intravenous challenge. The specificity of protection was confirmed by vaccinating mice with multiple CSP constructs of differing lengths and compositions. Constructs that induced high NANP repeat-specific antibody titers in enzyme-linked immunosorbent assays were protective, and the degree of protection was dependent on the antigen dose. There was a positive correlation between antibody avidity and protection. The antibodies in the protected mice recognized the native CSP on the parasites and showed sporozoite invasion inhibitory activity. Passive transfer of anti-CSP antibodies into naive mice also induced protection. Thus, we have demonstrated the utility of a mouse efficacy model to down-select human CSP-based vaccine formulations. PMID:23536694

Plant-derived H7 VLP vaccine elicits protective immune response against H7N9 influenza virus in mice and ferrets.

PubMed

Pillet, S; Racine, T; Nfon, C; Di Lenardo, T Z; Babiuk, S; Ward, B J; Kobinger, G P; Landry, N

2015-11-17

In March 2013, the Chinese Centre for Disease Control and Prevention confirmed the first reported case of human infection with an avian influenza A H7N9 virus. Infection with this virus often caused severe pneumonia and acute respiratory distress syndrome resulting in a case fatality rate >35%. The risk of pandemic highlighted, once again, the need for a more rapid and scalable vaccine response capability. Here, we describe the rapid (19 days) development of a plant-derived VLP vaccine based on the hemagglutinin sequence of influenza H7N9 A/Hangzhou/1/2013. The immunogenicity of the H7 VLP vaccine was assessed in mice and ferrets after one or two intramuscular dose(s) with and without adjuvant (alum or GLA-SE™). In ferrets, we also measured H7-specific cell-mediated immunity. The mice and ferrets were then challenged with H7N9 A/Anhui/1/2013 influenza virus. A single immunization with the adjuvanted vaccine elicited a strong humoral response and protected mice against an otherwise lethal challenge. Two doses of unadjuvanted vaccine significantly increased humoral response and resulted in 100% protection with significant reduction of clinical signs leading to nearly asymptomatic infections. In ferrets, a single immunization with the alum-adjuvanted H7 VLP vaccine induced strong humoral and CMI responses with antigen-specific activation of CD3(+) T cells. Compared to animals injected with placebo, ferrets vaccinated with alum-adjuvanted vaccine displayed no weight loss during the challenge. Moreover, the vaccination significantly reduced the viral load in lungs and nasal washes 3 days after the infection. This candidate plant-made H7 vaccine therefore induced protective responses after either one adjuvanted or two unadjuvanted doses. Studies are currently ongoing to better characterize the immune response elicited by the plant-derived VLP vaccines. Regardless, these data are very promising for the rapid production of an immunogenic and protective vaccine against

Vesicular Stomatitis Virus Pseudotyped with Ebola Virus Glycoprotein Serves as a Protective, Noninfectious Vaccine against Ebola Virus Challenge in Mice

PubMed Central

Lennemann, Nicholas J.; Herbert, Andrew S.; Brouillette, Rachel; Rhein, Bethany; Bakken, Russell A.; Perschbacher, Katherine J.; Cooney, Ashley L.; Miller-Hunt, Catherine L.; Ten Eyck, Patrick; Biggins, Julia; Olinger, Gene; Dye, John M.

2017-01-01

ABSTRACT The recent Ebola virus (EBOV) epidemic in West Africa demonstrates the potential for a significant public health burden caused by filoviral infections. No vaccine or antiviral is currently FDA approved. To expand the vaccine options potentially available, we assessed protection conferred by an EBOV vaccine composed of vesicular stomatitis virus pseudovirions that lack native G glycoprotein (VSVΔG) and bear EBOV glycoprotein (GP). These pseudovirions mediate a single round of infection. Both single-dose and prime/boost vaccination regimens protected mice against lethal challenge with mouse-adapted Ebola virus (ma-EBOV) in a dose-dependent manner. The prime/boost regimen provided significantly better protection than a single dose. As N-linked glycans are thought to shield conserved regions of the EBOV GP receptor-binding domain (RBD), thereby blocking epitopes within the RBD, we also tested whether VSVΔG bearing EBOV GPs that lack GP1 N-linked glycans provided effective immunity against challenge with ma-EBOV or a more distantly related virus, Sudan virus. Using a prime/boost strategy, high doses of GP/VSVΔG partially or fully denuded of N-linked glycans on GP1 protected mice against ma-EBOV challenge, but these mutants were no more effective than wild-type (WT) GP/VSVΔG and did not provide cross protection against Sudan virus. As reported for other EBOV vaccine platforms, the protection conferred correlated with the quantity of EBOV GP-specific Ig produced but not with the production of neutralizing antibodies. Our results show that EBOV GP/VSVΔG pseudovirions serve as a successful vaccination platform in a rodent model of Ebola virus disease and that GP1 N-glycan loss does not influence immunogenicity or vaccination success. IMPORTANCE The West African Ebola virus epidemic was the largest to date, with more than 28,000 people infected. No FDA-approved vaccines are yet available, but in a trial vaccination strategy in West Africa, recombinant

Recombinant Rift Valley fever vaccines induce protective levels of antibody in baboons and resistance to lethal challenge in mice

PubMed Central

Papin, James F.; Verardi, Paulo H.; Jones, Leslie A.; Monge-Navarro, Francisco; Brault, Aaron C.; Holbrook, Michael R.; Worthy, Melissa N.; Freiberg, Alexander N.; Yilma, Tilahun D.

2011-01-01

Rift Valley fever (RVF) is a zoonotic disease endemic in Africa and the Arabian Peninsula caused by the highly infectious Rift Valley fever virus (RVFV) that can be lethal to humans and animals and results in major losses in the livestock industry. RVF is exotic to the United States; however, mosquito species native to this region can serve as biological vectors for the virus. Thus, accidental or malicious introduction of this virus could result in RVFV becoming endemic in North America. Such an event would likely lead to significant morbidity and mortality in humans, and devastating economic effects on the livestock industry. Currently, there are no licensed vaccines for RVF that are both safe and efficacious. To address this issue, we developed two recombinant RVFV vaccines using vaccinia virus (VACV) as a vector for use in livestock. The first vaccine, vCOGnGc, was attenuated by the deletion of a VACV gene encoding an IFN-γ binding protein, insertional inactivation of the thymidine kinase gene, and expression of RVFV glycoproteins, Gn and Gc. The second vaccine, vCOGnGcγ, is identical to the first and also expresses the human IFN-γ gene to enhance safety. Both vaccines are extremely safe; neither resulted in weight loss nor death in severe combined immunodeficient mice, and pock lesions were smaller in baboons compared with the controls. Furthermore, both vaccines induced protective levels of antibody titers in vaccinated mice and baboons. Mice were protected from lethal RVFV challenge. Thus, we have developed two safe and efficacious recombinant vaccines for RVF. PMID:21873194

Vaccines. An Ebola whole-virus vaccine is protective in nonhuman primates.

PubMed

Marzi, Andrea; Halfmann, Peter; Hill-Batorski, Lindsay; Feldmann, Friederike; Shupert, W Lesley; Neumann, Gabriele; Feldmann, Heinz; Kawaoka, Yoshihiro

2015-04-24

Zaire ebolavirus is the causative agent of the current outbreak of hemorrhagic fever disease in West Africa. Previously, we showed that a whole Ebola virus (EBOV) vaccine based on a replication-defective EBOV (EBOVΔVP30) protects immunized mice and guinea pigs against lethal challenge with rodent-adapted EBOV. Here, we demonstrate that EBOVΔVP30 protects nonhuman primates against lethal infection with EBOV. Although EBOVΔVP30 is replication-incompetent, we additionally inactivated the vaccine with hydrogen peroxide; the chemically inactivated vaccine remained antigenic and protective in nonhuman primates. EBOVΔVP30 thus represents a safe, efficacious, whole-EBOV vaccine candidate that differs from other EBOV vaccine platforms in that it presents all viral proteins and the viral RNA to the host immune system, which might contribute to protective immune responses. Copyright © 2015, American Association for the Advancement of Science.

A Replication-Defective Human Type 5 Adenovirus-Based Trivalent Vaccine Confers Complete Protection against Plague in Mice and Nonhuman Primates

PubMed Central

Kirtley, Michelle L.; Klages, Curtis; Erova, Tatiana E.; Telepnev, Maxim; Ponnusamy, Duraisamy; Fitts, Eric C.; Baze, Wallace B.; Sivasubramani, Satheesh K.; Lawrence, William S.; Patrikeev, Igor; Peel, Jennifer E.; Andersson, Jourdan A.; Kozlova, Elena V.; Tiner, Bethany L.; Peterson, Johnny W.; McWilliams, David; Patel, Snehal; Rothe, Eric; Motin, Vladimir L.

2016-01-01

Currently, no plague vaccine exists in the United States for human use. The capsular antigen (Caf1 or F1) and two type 3 secretion system (T3SS) components, the low-calcium-response V antigen (LcrV) and the needle protein YscF, represent protective antigens of Yersinia pestis. We used a replication-defective human type 5 adenovirus (Ad5) vector and constructed recombinant monovalent and trivalent vaccines (rAd5-LcrV and rAd5-YFV) that expressed either the codon-optimized lcrV or the fusion gene designated YFV (consisting of ycsF, caf1, and lcrV). Immunization of mice with the trivalent rAd5-YFV vaccine by either the intramuscular (i.m.) or the intranasal (i.n.) route provided protection superior to that with the monovalent rAd5-LcrV vaccine against bubonic and pneumonic plague when animals were challenged with Y. pestis CO92. Preexisting adenoviral immunity did not diminish the protective response, and the protection was always higher when mice were administered one i.n. dose of the trivalent vaccine (priming) followed by a single i.m. booster dose of the purified YFV antigen. Immunization of cynomolgus macaques with the trivalent rAd5-YFV vaccine by the prime-boost strategy provided 100% protection against a stringent aerosol challenge dose of CO92 to animals that had preexisting adenoviral immunity. The vaccinated and challenged macaques had no signs of disease, and the invading pathogen rapidly cleared with no histopathological lesions. This is the first report showing the efficacy of an adenovirus-vectored trivalent vaccine against pneumonic plague in mouse and nonhuman primate (NHP) models. PMID:27170642

Oral vaccination with an adenovirus-vectored vaccine protects against botulism

PubMed Central

Chen, Shan; Xu, Qingfu; Zeng, Mingtao

2013-01-01

We have previously shown that an adenovirus vectored vaccine delivered intramuscularly or intranasally was effective in protection against botulism in a mouse model. The adenoviral vector encodes a human codon-optimized heavy chain C-fragment (HC50) of botulinum neurotoxin type C (BoNT/C). Here, we evaluate the same vaccine candidate as an oral vaccine against BoNT/C in a mouse model. To elicit protective immunity, the mice were orally vaccinated with a single dose of 1×104 to 1×107 plaque forming units (pfu) of the adenoviral vector. The immune sera, collected six weeks after oral vaccination with 2×107 pfu adenovirus, has shown an ability to neutralize the biological activity of BoNT/C in vitro. Additionally, animals receiving a single dose of 2×106 pfu adenovirus or greater were completely protected against challenge with 100×MLD50 of BoNT/C. The data demonstrated the feasibility to develop an adenovirus-based oral vaccine against botulism. PMID:23295065

Vaccination with nontoxic mutant toxic shock syndrome toxin 1 protects against Staphylococcus aureus infection.

PubMed

Hu, Dong-Liang; Omoe, Katsuhiko; Sasaki, Sanae; Sashinami, Hiroshi; Sakuraba, Hirotake; Yokomizo, Yuichi; Shinagawa, Kunihiro; Nakane, Akio

2003-09-01

To investigate whether vaccination with nontoxic mutant toxic shock syndrome toxin 1 (mTSST-1) can protect against Staphylococcus aureus infection, mice were vaccinated with mTSST-1 and challenged with viable S. aureus. Survival in the mTSST-1-vaccinated group was higher, and bacterial counts in organs were significantly lower than those of control mice. Passive transfer of mTSST-1-specific antibodies also provided protection against S. aureus-induced septic death. Interferon (IFN)-gamma production in the serum samples and spleens from vaccinated mice was significantly decreased compared with that in controls, whereas interleukin-10 titers were significantly higher in vaccinated mice. IFN-gamma and tumor necrosis factor-alpha production in vitro were significantly inhibited by serum samples from mTSST-1-immunized mice but not from control mice. These results suggest that vaccination with mTSST-1 devoid of superantigenic properties provides protection against S. aureus infection and that the protection might be mediated by TSST-1-neutralizing antibodies as well as by the down-regulation of IFN-gamma production.

Vaccination with lentiviral vector expressing the nfa1 gene confers a protective immune response to mice infected with Naegleria fowleri.

PubMed

Kim, Jong-Hyun; Sohn, Hae-Jin; Lee, Jinyoung; Yang, Hee-Jong; Chwae, Yong-Joon; Kim, Kyongmin; Park, Sun; Shin, Ho-Joon

2013-07-01

Naegleria fowleri, a pathogenic free-living amoeba, causes fatal primary amoebic meningoencephalitis (PAM) in humans and animals. The nfa1 gene (360 bp), cloned from a cDNA library of N. fowleri, produces a 13.1-kDa recombinant protein which is located on pseudopodia, particularly the food cup structure. The nfa1 gene plays an important role in the pathogenesis of N. fowleri infection. To examine the effect of nfa1 DNA vaccination against N. fowleri infection, we constructed a lentiviral vector (pCDH) expressing the nfa1 gene. For the in vivo mouse study, BALB/c mice were intranasally vaccinated with viral particles of a viral vector expressing the nfa1 gene. To evaluate the effect of vaccination and immune responses of mice, we analyzed the IgG levels (IgG, IgG1, and IgG2a), cytokine induction (interleukin-4 [IL-4] and gamma interferon [IFN-γ]), and survival rates of mice that developed PAM. The levels of both IgG and IgG subclasses (IgG1 and IgG2a) in vaccinated mice were significantly increased. The cytokine analysis showed that vaccinated mice exhibited greater IL-4 and IFN-γ production than the other control groups, suggesting a Th1/Th2 mixed-type immune response. In vaccinated mice, high levels of Nfa1-specific IgG antibodies continued until 12 weeks postvaccination. The mice vaccinated with viral vector expressing the nfa1 gene also exhibited significantly higher survival rates (90%) after challenge with N. fowleri trophozoites. Finally, the nfa1 vaccination effectively induced protective immunity by humoral and cellular immune responses in N. fowleri-infected mice. These results suggest that DNA vaccination using a viral vector may be a potential tool against N. fowleri infection.

Vaccination with Lentiviral Vector Expressing the nfa1 Gene Confers a Protective Immune Response to Mice Infected with Naegleria fowleri

PubMed Central

Kim, Jong-Hyun; Sohn, Hae-Jin; Lee, Jinyoung; Yang, Hee-Jong; Chwae, Yong-Joon; Kim, Kyongmin; Park, Sun

2013-01-01

Naegleria fowleri, a pathogenic free-living amoeba, causes fatal primary amoebic meningoencephalitis (PAM) in humans and animals. The nfa1 gene (360 bp), cloned from a cDNA library of N. fowleri, produces a 13.1-kDa recombinant protein which is located on pseudopodia, particularly the food cup structure. The nfa1 gene plays an important role in the pathogenesis of N. fowleri infection. To examine the effect of nfa1 DNA vaccination against N. fowleri infection, we constructed a lentiviral vector (pCDH) expressing the nfa1 gene. For the in vivo mouse study, BALB/c mice were intranasally vaccinated with viral particles of a viral vector expressing the nfa1 gene. To evaluate the effect of vaccination and immune responses of mice, we analyzed the IgG levels (IgG, IgG1, and IgG2a), cytokine induction (interleukin-4 [IL-4] and gamma interferon [IFN-γ]), and survival rates of mice that developed PAM. The levels of both IgG and IgG subclasses (IgG1 and IgG2a) in vaccinated mice were significantly increased. The cytokine analysis showed that vaccinated mice exhibited greater IL-4 and IFN-γ production than the other control groups, suggesting a Th1/Th2 mixed-type immune response. In vaccinated mice, high levels of Nfa1-specific IgG antibodies continued until 12 weeks postvaccination. The mice vaccinated with viral vector expressing the nfa1 gene also exhibited significantly higher survival rates (90%) after challenge with N. fowleri trophozoites. Finally, the nfa1 vaccination effectively induced protective immunity by humoral and cellular immune responses in N. fowleri-infected mice. These results suggest that DNA vaccination using a viral vector may be a potential tool against N. fowleri infection. PMID:23677321

Age Dependence of Immunity Induced by a Candidate Universal Influenza Vaccine in Mice

PubMed Central

García, Mayra; Misplon, Julia A.; Price, Graeme E.; Lo, Chia-Yun; Epstein, Suzanne L.

2016-01-01

Influenza has a major impact on the elderly due to increased susceptibility to infection with age and poor response to current vaccines. We have studied universal influenza vaccine candidates based on influenza A nucleoprotein and matrix 2 (A/NP+M2). Long-lasting protection against influenza virus strains of divergent subtypes is induced, especially with mucosal immunization. Here, we tested universal vaccination in BALB/c mice of different ages. Vaccination used intramuscular DNA priming to A/NP+M2 followed by intranasal (i.n.) boosting with recombinant adenoviruses (rAd) expressing the same antigens, or only A/NP+M2-rAd given i.n. Antigen-specific systemic antibody responses were induced in young, middle-aged, and elderly mice (2, 11–17, and 20 months old, respectively), but decreased with age. Antibody responses in bronchoalveolar lavage (BAL) were detected only in young mice. Antigen-specific T cell responses were seen in young and middle-aged but not elderly mice. A/NP+M2 vaccination by the two regimens above protected against stringent challenge in young and middle-aged mice, but not in elderly mice. However, mice vaccinated with A/NP-rAd or A/M2-rAd during their youth were partially protected against challenge 16 months later when they were elderly. In addition, a regimen of two doses of A/NP+M2-rAd given i.n. one month apart beginning in old age protected elderly mice against stringent challenge. This study highlights the potential benefit of cross-protective vaccines through middle age, and suggests that their performance might be enhanced in elderly individuals who had been exposed to influenza antigens early in life, as most humans have been, or by a two-dose rAd regimen given later in life. PMID:27055234

Age Dependence of Immunity Induced by a Candidate Universal Influenza Vaccine in Mice.

PubMed

García, Mayra; Misplon, Julia A; Price, Graeme E; Lo, Chia-Yun; Epstein, Suzanne L

2016-01-01

Influenza has a major impact on the elderly due to increased susceptibility to infection with age and poor response to current vaccines. We have studied universal influenza vaccine candidates based on influenza A nucleoprotein and matrix 2 (A/NP+M2). Long-lasting protection against influenza virus strains of divergent subtypes is induced, especially with mucosal immunization. Here, we tested universal vaccination in BALB/c mice of different ages. Vaccination used intramuscular DNA priming to A/NP+M2 followed by intranasal (i.n.) boosting with recombinant adenoviruses (rAd) expressing the same antigens, or only A/NP+M2-rAd given i.n. Antigen-specific systemic antibody responses were induced in young, middle-aged, and elderly mice (2, 11-17, and 20 months old, respectively), but decreased with age. Antibody responses in bronchoalveolar lavage (BAL) were detected only in young mice. Antigen-specific T cell responses were seen in young and middle-aged but not elderly mice. A/NP+M2 vaccination by the two regimens above protected against stringent challenge in young and middle-aged mice, but not in elderly mice. However, mice vaccinated with A/NP-rAd or A/M2-rAd during their youth were partially protected against challenge 16 months later when they were elderly. In addition, a regimen of two doses of A/NP+M2-rAd given i.n. one month apart beginning in old age protected elderly mice against stringent challenge. This study highlights the potential benefit of cross-protective vaccines through middle age, and suggests that their performance might be enhanced in elderly individuals who had been exposed to influenza antigens early in life, as most humans have been, or by a two-dose rAd regimen given later in life.

Immunogenicity, Protective Efficacy, and Non-Replicative Status of the HSV-2 Vaccine Candidate HSV529 in Mice and Guinea Pigs

PubMed Central

Bernard, Marie-Clotilde; Barban, Véronique; Pradezynski, Fabrine; de Montfort, Aymeric; Ryall, Robert; Caillet, Catherine; Londono-Hayes, Patricia

2015-01-01

HSV-2 vaccine is needed to prevent genital disease, latent infection, and virus transmission. A replication-deficient mutant virus (dl5-29) has demonstrated promising efficacy in animal models of genital herpes. However, the immunogenicity, protective efficacy, and non-replicative status of the highly purified clinical vaccine candidate (HSV529) derived from dl5-29 have not been evaluated. Humoral and cellular immune responses were measured in mice and guinea pigs immunized with HSV529. Protection against acute and recurrent genital herpes, mortality, latent infection, and viral shedding after vaginal HSV-2 infection was determined in mice or in naïve and HSV-1 seropositive guinea pigs. HSV529 replication and pathogenicity were investigated in three sensitive models of virus replication: severe combined immunodeficient (SCID/Beige) mice inoculated by the intramuscular route, suckling mice inoculated by the intracranial route, and vaginally-inoculated guinea pigs. HSV529 immunization induced HSV-2-neutralizing antibody production in mice and guinea pigs. In mice, it induced production of specific HSV-2 antibodies and splenocytes secreting IFNγ or IL-5. Immunization effectively prevented HSV-2 infection in all three animal models by reducing mortality, acute genital disease severity and frequency, and viral shedding. It also reduced ganglionic viral latency and recurrent disease in naïve and HSV-1 seropositive guinea pigs. HSV529 replication/propagation was not detected in the muscles of SCID/Beige mice, in the brains of suckling mice, or in vaginal secretions of inoculated guinea pigs. These results confirm the non-replicative status, as well as its immunogenicity and efficacy in mice and guinea pigs, including HSV-1 seropositive guinea pigs. In mice, HSV529 produced Th1/Th2 characteristic immune response thought to be necessary for an effective vaccine. These results further support the clinical investigation of HSV529 in human subjects as a prophylactic vaccine

Vaccine Mediated Protection Against Zika Virus-Induced Congenital Disease.

PubMed

Richner, Justin M; Jagger, Brett W; Shan, Chao; Fontes, Camila R; Dowd, Kimberly A; Cao, Bin; Himansu, Sunny; Caine, Elizabeth A; Nunes, Bruno T D; Medeiros, Daniele B A; Muruato, Antonio E; Foreman, Bryant M; Luo, Huanle; Wang, Tian; Barrett, Alan D; Weaver, Scott C; Vasconcelos, Pedro F C; Rossi, Shannan L; Ciaramella, Giuseppe; Mysorekar, Indira U; Pierson, Theodore C; Shi, Pei-Yong; Diamond, Michael S

2017-07-13

The emergence of Zika virus (ZIKV) and its association with congenital malformations has prompted the rapid development of vaccines. Although efficacy with multiple viral vaccine platforms has been established in animals, no study has addressed protection during pregnancy. We tested in mice two vaccine platforms, a lipid nanoparticle-encapsulated modified mRNA vaccine encoding ZIKV prM and E genes and a live-attenuated ZIKV strain encoding an NS1 protein without glycosylation, for their ability to protect against transmission to the fetus. Vaccinated dams challenged with a heterologous ZIKV strain at embryo day 6 (E6) and evaluated at E13 showed markedly diminished levels of viral RNA in maternal, placental, and fetal tissues, which resulted in protection against placental damage and fetal demise. As modified mRNA and live-attenuated vaccine platforms can restrict in utero transmission of ZIKV in mice, their further development in humans to prevent congenital ZIKV syndrome is warranted. Copyright © 2017 Elsevier Inc. All rights reserved.

A live attenuated cold adapted influenza A H7N3 virus vaccine provides protection against homologous and heterologous H7 viruses in mice and ferrets

PubMed Central

Joseph, Tomy; McAuliffe, Josephine; Lu, Bin; Vogel, Leatrice; Swayne, David; Jin, Hong; Kemble, George; Subbarao, Kanta

2008-01-01

The appearance of human infections caused by avian influenza A H7 subtype viruses underscore their pandemic potential and the need to develop vaccines to protect humans from viruses of this subtype. A live attenuated H7N3 virus vaccine was generated by reverse genetics using the HA and NA genes of a low pathogenicity A/chicken/BC/CN-6/04 (H7N3) virus and the six internal protein genes of the cold-adapted A/Ann Arbor/6/60 ca (H2N2) virus. The reassortant H7N3 BC 04 ca vaccine virus was temperature sensitive and showed attenuation in mice and ferrets. Intranasal immunization with one dose of the vaccine protected mice and ferrets when challenged with homologous and heterologous H7 viruses. The reassortant H7N3 BC 04 ca vaccine virus showed comparable levels of attenuation, immunogenicity and efficacy in mice and ferret models. The safety, immunogenicity, and efficacy of this vaccine in mice and ferrets support the evaluation of this vaccine in clinical trials. PMID:18585748

A live attenuated cold-adapted influenza A H7N3 virus vaccine provides protection against homologous and heterologous H7 viruses in mice and ferrets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joseph, Tomy; MedImmune Inc., Mountain View, CA 94043; McAuliffe, Josephine

2008-08-15

The appearance of human infections caused by avian influenza A H7 subtype viruses underscores their pandemic potential and the need to develop vaccines to protect humans from viruses of this subtype. A live attenuated H7N3 virus vaccine was generated by reverse genetics using the HA and NA genes of a low pathogenicity A/chicken/BC/CN-6/04 (H7N3) virus and the six internal protein genes of the cold-adapted A/Ann Arbor/6/60 ca (H2N2) virus. The reassortant H7N3 BC 04 ca vaccine virus was temperature sensitive and showed attenuation in mice and ferrets. Intranasal immunization with one dose of the vaccine protected mice and ferrets whenmore » challenged with homologous and heterologous H7 viruses. The reassortant H7N3 BC 04 ca vaccine virus showed comparable levels of attenuation, immunogenicity and efficacy in mice and ferret models. The safety, immunogenicity, and efficacy of this vaccine in mice and ferrets support the evaluation of this vaccine in clinical trials.« less

Two Novel Salmonella Bivalent Vaccines Confer Dual Protection against Two Salmonella Serovars in Mice

PubMed Central

Zhao, Xinxin; Dai, Qinlong; Jia, Renyong; Zhu, Dekang; Liu, Mafeng; Wang, Mingshu; Chen, Shun; Sun, Kunfeng; Yang, Qiao; Wu, Ying; Cheng, Anchun

2017-01-01

Newport lethal challenge. All of the mice in the three vaccine-immunized groups survived the lethal Salmonella Typhimurium challenge. In contrast, SLT26 (pCZ11) and SLT27 (pCZ11) conferred full protection against lethal Salmonella Newport challenge, but SLT25 (pCZ11) provided only 50% heterologous protection. Thus, we developed two novel Salmonella bivalent vaccines, SLT26 (pCZ11) and SLT27 (pCZ11), suggesting that the delivery of a heterologous O-antigen in attenuated Salmonella strains is a prospective approach for developing Salmonella vaccines with broad serovar coverage. PMID:28929089

A Replication-Defective Human Type 5 Adenovirus-Based Trivalent Vaccine Confers Complete Protection against Plague in Mice and Nonhuman Primates.

PubMed

Sha, Jian; Kirtley, Michelle L; Klages, Curtis; Erova, Tatiana E; Telepnev, Maxim; Ponnusamy, Duraisamy; Fitts, Eric C; Baze, Wallace B; Sivasubramani, Satheesh K; Lawrence, William S; Patrikeev, Igor; Peel, Jennifer E; Andersson, Jourdan A; Kozlova, Elena V; Tiner, Bethany L; Peterson, Johnny W; McWilliams, David; Patel, Snehal; Rothe, Eric; Motin, Vladimir L; Chopra, Ashok K

2016-07-01

Currently, no plague vaccine exists in the United States for human use. The capsular antigen (Caf1 or F1) and two type 3 secretion system (T3SS) components, the low-calcium-response V antigen (LcrV) and the needle protein YscF, represent protective antigens of Yersinia pestis We used a replication-defective human type 5 adenovirus (Ad5) vector and constructed recombinant monovalent and trivalent vaccines (rAd5-LcrV and rAd5-YFV) that expressed either the codon-optimized lcrV or the fusion gene designated YFV (consisting of ycsF, caf1, and lcrV). Immunization of mice with the trivalent rAd5-YFV vaccine by either the intramuscular (i.m.) or the intranasal (i.n.) route provided protection superior to that with the monovalent rAd5-LcrV vaccine against bubonic and pneumonic plague when animals were challenged with Y. pestis CO92. Preexisting adenoviral immunity did not diminish the protective response, and the protection was always higher when mice were administered one i.n. dose of the trivalent vaccine (priming) followed by a single i.m. booster dose of the purified YFV antigen. Immunization of cynomolgus macaques with the trivalent rAd5-YFV vaccine by the prime-boost strategy provided 100% protection against a stringent aerosol challenge dose of CO92 to animals that had preexisting adenoviral immunity. The vaccinated and challenged macaques had no signs of disease, and the invading pathogen rapidly cleared with no histopathological lesions. This is the first report showing the efficacy of an adenovirus-vectored trivalent vaccine against pneumonic plague in mouse and nonhuman primate (NHP) models. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Protective Vaccination against Blood-Stage Malaria of Plasmodium chabaudi: Differential Gene Expression in the Liver of Balb/c Mice toward the End of Crisis Phase

PubMed Central

Al-Quraishy, Saleh A.; Dkhil, Mohamed A.; Abdel-Baki, Abdel-Azeem A.; Delic, Denis; Wunderlich, Frank

2016-01-01

Protective vaccination induces self-healing of otherwise fatal blood-stage malaria of Plasmodium chabaudi in female Balb/c mice. To trace processes critically involved in self-healing, the liver, an effector against blood-stage malaria, is analyzed for possible changes of its transcriptome in vaccination-protected in comparison to non-protected mice toward the end of the crisis phase. Gene expression microarray analyses reveal that vaccination does not affect constitutive expression of mRNA and lincRNA. However, malaria induces significant (p < 0.01) differences in hepatic gene and lincRNA expression in vaccination-protected vs. non-vaccinated mice toward the end of crisis phase. In vaccination-protected mice, infections induce up-regulations of 276 genes and 40 lincRNAs and down-regulations of 200 genes and 43 lincRNAs, respectively, by >3-fold as compared to the corresponding constitutive expressions. Massive up-regulations, partly by >100-fold, are found for genes as RhD, Add2, Ank1, Ermap, and Slc4a, which encode proteins of erythrocytic surface membranes, and as Gata1 and Gfi1b, which encode transcription factors involved in erythrocytic development. Also, Cldn13 previously predicted to be expressed on erythroblast surfaces is up-regulated by >200-fold, though claudins are known as main constituents of tight junctions acting as paracellular barriers between epithelial cells. Other genes are up-regulated by <100- and >10-fold, which can be subgrouped in genes encoding proteins known to be involved in mitosis, in cell cycle regulation, and in DNA repair. Our data suggest that protective vaccination enables the liver to respond to P. chabaudi infections with accelerated regeneration and extramedullary erythropoiesis during crisis, which contributes to survival of otherwise lethal blood-stage malaria. PMID:27471498

An oral vaccine based on U-Omp19 induces protection against B. abortus mucosal challenge by inducing an adaptive IL-17 immune response in mice.

PubMed

Pasquevich, Karina A; Ibañez, Andrés E; Coria, Lorena M; García Samartino, Clara; Estein, Silvia M; Zwerdling, Astrid; Barrionuevo, Paula; Oliveira, Fernanda S; Seither, Christine; Warzecha, Heribert; Oliveira, Sergio C; Giambartolomei, Guillermo H; Cassataro, Juliana

2011-01-14

As Brucella infections occur mainly through mucosal surfaces, the development of mucosal administered vaccines could be radical for the control of brucellosis. In this work we evaluated the potential of Brucella abortus 19 kDa outer membrane protein (U-Omp19) as an edible subunit vaccine against brucellosis. We investigated the protective immune response elicited against oral B. abortus infection after vaccination of mice with leaves from transgenic plants expressing U-Omp19; or with plant-made or E. coli-made purified U-Omp19. All tested U-Omp19 formulations induced protection against Brucella when orally administered without the need of adjuvants. U-Omp19 also induced protection against a systemic challenge when parenterally administered. This built-in adjuvant ability of U-Omp19 was independent of TLR4 and could be explained at least in part by its capability to activate dendritic cells in vivo. While unadjuvanted U-Omp19 intraperitoneally administered induced a specific Th1 response, following U-Omp19 oral delivery a mixed specific Th1-Th17 response was induced. Depletion of CD4(+) T cells in mice orally vaccinated with U-Omp19 resulted in a loss of the elicited protection, indicating that this cell type mediates immune protection. The role of IL-17 against Brucella infection has never been explored. In this study, we determined that if IL-17A was neutralized in vivo during the challenge period, the mucosal U-Omp19 vaccine did not confer mucosal protection. On the contrary, IL-17A neutralization during the infection did not influence at all the subsistence and growth of this bacterium in PBS-immunized mice. All together, our results indicate that an oral unadjuvanted vaccine based on U-Omp19 induces protection against a mucosal challenge with Brucella abortus by inducing an adaptive IL-17 immune response. They also indicate different and important new aspects i) IL-17 does not contribute to reduce the bacterial burden in non vaccinated mice and ii) IL-17 plays

Enhanced protective immune response to PCV2 subunit vaccine by co-administration of recombinant porcine IFN-γ in mice.

PubMed

Wang, Yi-Ping; Liu, Dan; Guo, Long-Jun; Tang, Qing-Hai; Wei, Yan-Wu; Wu, Hong-Li; Liu, Jian-Bo; Li, Sheng-Bin; Huang, Li-Ping; Liu, Chang-Ming

2013-01-21

The capsid (Cap) protein of PCV2 is the major immunogenic protein that is crucial to induce PCV2-specific neutralizing antibodies and protective immunity; thus, it is a suitable target antigen for the research and development of genetically engineered vaccines against PCV2 infection. IFN-γ has exhibited potential efficacy as an immune adjuvant that enhances the immunogenicity of certain vaccines in experimental animal models. In this study, three recombinant proteins: PCV2-Cap protein, porcine IFN-γ (PoIFN-γ), and the fusion protein (Cap-PoIFN-γ) of PCV2-Cap protein and PoIFN-γ were respectively expressed in the baculovirus system, and analyzed by Western blot and indirect ELISA. Additionally, we evaluated the enhancement of the protective immune response to the Cap protein-based PCV2 subunit vaccine elicited by co-administration of PoIFN-γ in mice. Vaccination of mice with the PCV2-Cap+PoIFN-γ vaccine elicited significantly higher levels of PCV2-specific IPMA antibodies, neutralizing antibodies, and lymphocyte proliferative responses compared to the Cap-PoIFN-γ vaccine, the PCV2-Cap vaccine, and LG-strain. Following virulent PCV2 challenge, no viraemia was detected in all immunized groups, and the viral loads in lungs of the PCV2-Cap+PoIFN-γ group were significantly lower compared to the Cap-PoIFN-γ group, the LG-strain group, and the mock group, but slightly lower compared to the PCV2-Cap group. These findings suggested that PoIFN-γ substantially enhanced the protective immune response to the Cap protein-based PCV2 subunit vaccine, and that the PCV2-Cap+PoIFN-γ subunit vaccine potentially serves as an attractive candidate vaccine for the prevention and control of PCV2-associated diseases. Copyright © 2012 Elsevier Ltd. All rights reserved.

Maternal vaccination with a fimbrial tip adhesin and passive protection of neonatal mice against lethal human enterotoxigenic Escherichia coli challenge.

PubMed

Luiz, Wilson B; Rodrigues, Juliana F; Crabb, Joseph H; Savarino, Stephen J; Ferreira, Luis C S

2015-12-01

Globally, enterotoxigenic Escherichia coli (ETEC) is a leading cause of childhood and travelers' diarrhea, for which an effective vaccine is needed. Prevalent intestinal colonization factors (CFs) such as CFA/I fimbriae and heat-labile enterotoxin (LT) are important virulence factors and protective antigens. We tested the hypothesis that donor strand-complemented CfaE (dscCfaE), a stabilized form of the CFA/I fimbrial tip adhesin, is a protective antigen, using a lethal neonatal mouse ETEC challenge model and passive dam vaccination. For CFA/I-ETEC strain H10407, which has been extensively studied in volunteers, an inoculum of 2 × 10(7) bacteria resulted in 50% lethal doses (LD50) in neonatal DBA/2 mice. Vaccination of female DBA/2 mice with CFA/I fimbriae or dscCfaE, each given with a genetically attenuated LT adjuvant (LTK63) by intranasal or orogastric delivery, induced high antigen-specific serum IgG and fecal IgA titers and detectable milk IgA responses. Neonates born to and suckled by dams antenatally vaccinated with each of these four regimens showed 78 to 93% survival after a 20× LD50 challenge with H10407, compared to 100% mortality in pups from dams vaccinated with sham vaccine or LTK63 only. Crossover experiments showed that high pup survival rates after ETEC challenge were associated with suckling but not birthing from vaccinated dams, suggesting that vaccine-specific milk antibodies are protective. In corroboration, preincubation of the ETEC inoculum with antiadhesin and antifimbrial bovine colostral antibodies conferred a dose-dependent increase in pup survival after challenge. These findings indicate that the dscCfaE fimbrial tip adhesin serves as a protective passive vaccine antigen in this small animal model and merits further evaluation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Maternal Vaccination with a Fimbrial Tip Adhesin and Passive Protection of Neonatal Mice against Lethal Human Enterotoxigenic Escherichia coli Challenge

PubMed Central

Luiz, Wilson B.; Rodrigues, Juliana F.; Crabb, Joseph H.

2015-01-01

Globally, enterotoxigenic Escherichia coli (ETEC) is a leading cause of childhood and travelers' diarrhea, for which an effective vaccine is needed. Prevalent intestinal colonization factors (CFs) such as CFA/I fimbriae and heat-labile enterotoxin (LT) are important virulence factors and protective antigens. We tested the hypothesis that donor strand-complemented CfaE (dscCfaE), a stabilized form of the CFA/I fimbrial tip adhesin, is a protective antigen, using a lethal neonatal mouse ETEC challenge model and passive dam vaccination. For CFA/I-ETEC strain H10407, which has been extensively studied in volunteers, an inoculum of 2 × 107 bacteria resulted in 50% lethal doses (LD50) in neonatal DBA/2 mice. Vaccination of female DBA/2 mice with CFA/I fimbriae or dscCfaE, each given with a genetically attenuated LT adjuvant (LTK63) by intranasal or orogastric delivery, induced high antigen-specific serum IgG and fecal IgA titers and detectable milk IgA responses. Neonates born to and suckled by dams antenatally vaccinated with each of these four regimens showed 78 to 93% survival after a 20× LD50 challenge with H10407, compared to 100% mortality in pups from dams vaccinated with sham vaccine or LTK63 only. Crossover experiments showed that high pup survival rates after ETEC challenge were associated with suckling but not birthing from vaccinated dams, suggesting that vaccine-specific milk antibodies are protective. In corroboration, preincubation of the ETEC inoculum with antiadhesin and antifimbrial bovine colostral antibodies conferred a dose-dependent increase in pup survival after challenge. These findings indicate that the dscCfaE fimbrial tip adhesin serves as a protective passive vaccine antigen in this small animal model and merits further evaluation. PMID:26371126

Vaccination of Mice Using the West Nile Virus E-Protein in a DNA Prime-Protein Boost Strategy Stimulates Cell-Mediated Immunity and Protects Mice against a Lethal Challenge

PubMed Central

De Filette, Marina; Soehle, Silke; Ulbert, Sebastian; Richner, Justin; Diamond, Michael S.; Sinigaglia, Alessandro; Barzon, Luisa; Roels, Stefan; Lisziewicz, Julianna; Lorincz, Orsolya; Sanders, Niek N.

2014-01-01

West Nile virus (WNV) is a mosquito-borne flavivirus that is endemic in Africa, the Middle East, Europe and the United States. There is currently no antiviral treatment or human vaccine available to treat or prevent WNV infection. DNA plasmid-based vaccines represent a new approach for controlling infectious diseases. In rodents, DNA vaccines have been shown to induce B cell and cytotoxic T cell responses and protect against a wide range of infections. In this study, we formulated a plasmid DNA vector expressing the ectodomain of the E-protein of WNV into nanoparticles by using linear polyethyleneimine (lPEI) covalently bound to mannose and examined the potential of this vaccine to protect against lethal WNV infection in mice. Mice were immunized twice (prime – boost regime) with the WNV DNA vaccine formulated with lPEI-mannose using different administration routes (intramuscular, intradermal and topical). In parallel a heterologous boost with purified recombinant WNV envelope (E) protein was evaluated. While no significant E-protein specific humoral response was generated after DNA immunization, protein boosting of DNA-primed mice resulted in a marked increase in total neutralizing antibody titer. In addition, E-specific IL-4 T-cell immune responses were detected by ELISPOT after protein boost and CD8+ specific IFN-γ expression was observed by flow cytometry. Challenge experiments using the heterologous immunization regime revealed protective immunity to homologous and virulent WNV infection. PMID:24503579

Formalin-Inactivated Coxiella burnetii Phase I Vaccine-Induced Protection Depends on B Cells To Produce Protective IgM and IgG

PubMed Central

Peng, Ying; Schoenlaub, Laura; Elliott, Alexandra; Mitchell, William; Zhang, Yan

2013-01-01

To further understand the mechanisms of formalin-inactivated Coxiella burnetii phase I (PI) vaccine (PIV)-induced protection, we examined if B cell, T cell, CD4+ T cell, or CD8+ T cell deficiency in mice significantly affects the ability of PIV to confer protection against a C. burnetii infection. Interestingly, compared to wild-type (WT) mice, PIV conferred comparable levels of protection in CD4+ T cell- or CD8+ T cell-deficient mice and partial protection in T cell-deficient mice but did not provide measurable protection in B cell-deficient mice. These results suggest that PIV-induced protection depends on B cells. In addition, anti-PI-specific IgM was the major detectable antibody (Ab) in immune sera from PIV-vaccinated CD4+ T cell-deficient mice, and passive transfer of immune sera from PIV-vaccinated CD4+ T cell-deficient mice conferred significant protection. These results suggest that T cell-independent anti-PI-specific IgM may contribute to PIV-induced protection. Our results also suggested that PIV-induced protection may not depend on complement activation and Fc receptor-mediated effector functions. Furthermore, our results demonstrated that both IgM and IgG from PIV-vaccinated WT mouse sera were able to inhibit C. burnetii infection in vivo, but only IgM from PIV-vaccinated CD4+ T cell-deficient mouse sera inhibited C. burnetii infection. Collectively, these findings suggest that PIV-induced protection depends on B cells to produce protective IgM and IgG and that T cell-independent anti-PI-specific IgM may play a critical role in PIV-induced protection against C. burnetii infection. PMID:23545296

Induction of Protective Immunity against Toxoplasmosis in BALB/c Mice Vaccinated with Toxoplasma gondii Rhoptry-1

PubMed Central

Sonaimuthu, Parthasarathy; Ching, Xiao T.; Fong, Mun Y.; Kalyanasundaram, Ramaswamy; Lau, Yee L.

2016-01-01

Toxoplasma gondii is the causative agent for toxoplasmosis. The rhoptry protein 1 (ROP1) is secreted by rhoptry, an apical secretory organelle of the parasite. ROP1 plays an important role in host cell invasion. In this study, the efficacy of ROP1 as a vaccine candidate against toxoplasmosis was evaluated through intramuscular or subcutaneous injection of BALB/c mice followed by immunological characterization (humoral- and cellular-mediated) and lethal challenge against virulent T. gondii RH strain in BALB/c mice. Briefly, a recombinant DNA plasmid (pVAX1-GFP-ROP1) was expressed in CHO cells while expression of recombinant ROP1 protein (rROP1) was carried out in Escherichia coli expression system. Immunization study involved injection of the recombinant pVAX1-ROP1 and purified rROP1 into different group of mice. Empty vector and PBS served as two different types of negative controls. Results obtained demonstrated that ROP1 is an immunogenic antigen that induced humoral immune response whereby detection of a protein band with expected size of 43 kDa was observed against vaccinated mice sera through western blot analysis. ROP1 antigen was shown to elicit cellular-mediated immunity as well whereby stimulated splenocytes with total lysate antigen (TLA) and rROP1 from pVAX1-ROP1 and rROP1-immunized mice, respectively, readily proliferated and secreted large amount of IFN-γ (712 ± 28.1 pg/ml and 1457 ± 31.19 pg/ml, respectively) and relatively low IL-4 level (94 ± 14.5 pg/ml and 186 ± 14.17 pg/ml, respectively). These phenomena suggested that Th1-favored immunity was being induced. Vaccination with ROP1 antigen was able to provide partial protection in the vaccinated mice against lethal challenge with virulent RH strain of tachyzoites. These findings proposed that the ROP1 antigen is a potential candidate for the development of vaccine against toxoplasmosis. PMID:27303390

Vaccine-induced protection against anthrax in cheetah (Acinonyx jubatus) and black rhinoceros (Diceros bicornis).

PubMed

Turnbull, P C B; Tindall, B W; Coetzee, J D; Conradie, C M; Bull, R L; Lindeque, P M; Huebschle, O J B

2004-09-03

Institution of a policy of vaccination in endangered species with a vaccine not previously administered to it cannot be undertaken lightly. This applies even more in the case of cheetah (Acinonyx jubatus) with their unusually monomorphic gene pool and the potential restrictions this places on their immune responses. However, the recently observed mortalities from anthrax in these animals in the Etosha National Park, Namibia, made it imperative to evaluate vaccination. Black rhinoceros (Diceros bicornis), another endangered species in the park, have been vaccinated for over three decades but the effectiveness of this has never been evaluated. Passive protection tests in A/J mice using sera from 12 cheetahs together with enzyme immunoassay indicated that cheetah are able to mount seemingly normal primary and secondary humoral immune responses to the Sterne 34F2 live spore livestock vaccine. Overall protection rates in mice injected with the sera rose and fell in concert with rises and declines in antibody titres, although fine analysis showed that the correlation between titre and protection was complex. Once a high level of protection (96% of mice 1 month after a second booster in the cheetahs) had been achieved, the duration of substantial protection appeared good (60% of the mice 5 months after the second booster). Protection conferred on mice by sera from three of four vaccinated rhino was almost complete, but, obscurely, none of the mice receiving serum from the fourth rhino were protected. Sera from three park lions with naturally acquired high antibody titres, included as controls, also conferred high levels of protection. For the purposes of wildlife management, the conclusions were that vaccination of cheetah with the standard animal anthrax vaccine causes no observable ill effect in the animals and does appear to confer protective immunity. At least one well-separated booster does appear to be desirable. Vaccination of rhino also appears to be justified

Protection against Fasciola gigantica infection in mice by vaccination with recombinant juvenile-specific cathepsin L.

PubMed

Sansri, Veerawat; Meemon, Krai; Changklungmoa, Narin; Kueakhai, Pornanan; Chantree, Pathanin; Chaichanasak, Pannigan; Lorsuwannarat, Natcha; Itagaki, Tadashi; Sobhon, Prasert

2015-03-24

Fasciola gigantica cathepsin L1H (FgCatL1H) is one of the major cathepsin L released by juveniles of F. gigantica to aid in the invasion of host's tissues. Due to its high sequence similarity with other cathepsin L (CatL) isoforms of late stage F. gigantica, it was considered to be a good vaccine candidate that can block all CatL-mediated protease activities and affect juveniles as well as adult parasites. In this study, recombinant proFgCatL1H protein expressed in yeast, Pichia pastoris, system was mixed with Freund's adjuvants and used to subcutaneously immunize mice that were later challenged with metacercariae of F. gigantica. The percentage of worm protection in the rproFgCatL1H-vaccinated mice compared to the non-immunized and adjuvant control mice were approximately 62.7% and 66.1%, respectively. Anti-rproFgCatL1H antisera collected from vaccinated mice reacted specifically with rproFgCatL1H and other cathepsin L isoforms of F. gigantica, but the antibodies did not cross react with antigens from other trematode and nematode parasites, including Eurytrema pancreaticum, Opisthorchis viverrini, Fischoederius cobboldi, Cotylophoron cotylophorum, Gigantocotyle explanatum, Paramphistomum cervi, and Setaria labiato-papillosa. The levels of IgG1 and IgG2a in mouse sera increased significantly at two weeks after immunization and were highest during the sixth to eighth weeks after immunization. The IgG1 level was higher than IgG2a at all periods of immunization, implicating the dominance of the Th2 response. The levels of IgG1 and IgG2a in the immune sera were shown to be strongly correlated with the numbers of worm recovery, and the correlation coefficient was higher for IgG1. The levels of serum aspartate aminotransferase and alanine transaminase were significantly lower in the sera of rproFgCatL1H-vaccinated mice than in the infected control mice indicating a lower degree of liver damage. This study demonstrated a high potential of FgCatL1H vaccine, and its

A plant based protective antigen [PA(dIV)] vaccine expressed in chloroplasts demonstrates protective immunity in mice against anthrax.

PubMed

Gorantala, Jyotsna; Grover, Sonam; Goel, Divya; Rahi, Amit; Jayadev Magani, Sri Krishna; Chandra, Subhash; Bhatnagar, Rakesh

2011-06-15

The currently available anthrax vaccines are limited by being incompletely characterized, potentially reactogenic and have an expanded dosage schedule. Plant based vaccines offer safe alternative for vaccine production. In the present study, we expressed domain IV of Bacillus anthracis protective antigen gene [PA(dIV)] in planta (by nuclear agrobacterium and chloroplast transformation) and E. coli [rPA(dIV)]. The presence of transgene and the expression of PA(dIV) in planta was confirmed by molecular analysis. Expression levels up to 5.3% of total soluble protein (TSP) were obtained with AT rich (71.8% AT content) PA(dIV) gene in transplastomic plants while 0.8% of TSP was obtained in nuclear transformants. Further, we investigated the protective response of plant and E. coli derived PA(dIV) in mice by intraperitoneal (i.p.) and oral immunizations with or without adjuvant. Antibody titers of >10(4) were induced upon i.p. and oral immunizations with plant derived PA(dIV) and oral immunization with E. coli derived PA(dIV). Intraperitoneal injections with adjuvanted E. coli derived PA(dIV), generated highest antibody titers of >10(5). All the immunized groups demonstrated predominant IgG1 titers over IgG2a indicating a polarized Th2 type response. We also evaluated the mucosal antibody response in orally immunized groups. When fecal extracts were analyzed, low sIgA titer was demonstrated in adjuvanted plant and E. coli derived PA(dIV) groups. Further, PA(dIV) antisera enhanced B. anthracis spore uptake by macrophages in vitro and also demonstrated an anti-germinating effect suggesting a potent role at mucosal surfaces. The antibodies from various groups were efficient in neutralizing the lethal toxin in vitro. When mice were challenged with B. anthracis, mice immunized with adjuvanted plant PA(dIV) imparted 60% and 40% protection while E. coli derived PA(dIV) conferred 100% and 80% protection upon i.p. and oral immunizations. Thus, our study is the first attempt in

Complete Protection against Influenza Virus H1N1 Strain A/PR/8/34 Challenge in Mice Immunized with Non-Adjuvanted Novirhabdovirus Vaccines

PubMed Central

Rouxel, Ronan N.; Mérour, Emilie; Biacchesi, Stéphane; Brémont, Michel

2016-01-01

Novirhabdoviruses like Viral Hemorrhagic Septicemia Virus (VHSV) and Infectious Hematopoietic Necrosis Virus (IHNV) are fish-infecting Rhabdoviruses belonging to the Mononegavirales order. By reverse genetics, we previously showed that a recombinant VHSV expressing the West Nile Virus (WNV) E glycoprotein could serve as a vaccine platform against WNV. In the current study, we aimed to evaluate the potential of the Novirhabdovirus platform as a vaccine against influenza virus. Recombinant Novirhabdoviruses, rVHSV-HA and rIHNV-HA, expressing at the viral surface the hemagglutinin HA ectodomain were generated and used to immunized mice. We showed that mice immunized with either, rVHSV-HA or rIHNV-HA, elicited a strong neutralizing antibody response against influenza virus. A complete protection was conferred to the immunized mice when challenged with a lethal dose of influenza H1N1 A/PR/8/34 virus. Furthermore we showed that although acting as inert antigen in mice, since naturally inactivated over 20°C, mice immunized with rVHSV-HA or rIHNV-HA in the absence of adjuvant were also completely protected from a lethal challenge. Novirhabdoviruses platform are of particular interest as vaccines for mammals since they are cost effective to produce, relatively easy to generate and very effective to protect immunized animals. PMID:27711176

Phytol-based novel adjuvants in vaccine formulation: 2. Assessment of efficacy in the induction of protective immune responses to lethal bacterial infections in mice.

PubMed

Lim, So-Yon; Bauermeister, Adam; Kjonaas, Richard A; Ghosh, Swapan K

2006-10-23

Adjuvants are known to significantly enhance vaccine efficacy. However, commercial adjuvants often have limited use because of toxicity in humans. The objective of this study was to determine the comparative effectiveness of a diterpene alcohol, phytol and its hydrogenated derivative PHIS-01, relative to incomplete Freund's adjuvant (IFA), a commonly used adjuvant in augmenting protective immunity in mice against E. coli and S. aureus, and in terms of inflammatory cytokines. Vaccines, consisting of heat-attenuated E. coli or S. aureus and either of the two phytol-based adjuvants or IFA, were tested in female BALB/c mice. The vaccines were administered intraperitoneally at 10-day intervals. The efficacy of the phytol and PHIS-01, as compared to IFA, was assessed by ELISA in terms of anti-bacterial antibody and inflammatory cytokines. We also examined the ability of the vaccines to induce specific protective immunity by challenging mice with different doses of live bacteria. IFA, phytol, and PHIS-01 were equally efficient in evoking anti-E. coli antibody response and in providing protective immunity against live E. coli challenges. In contrast, the antibody response to S. aureus was significant when PHIS-01 was used as the adjuvant. However, in terms of the ability to induce protective immunity, phytol was most effective against S. aureus. Moreover, during challenges with live E. coli and S. aureus immune mice produced much less IL-6, the mediators of fatal septic shock syndromes. Our results show that vaccine formulations containing phytol and PHIS-01 as adjuvants confer a robust and protective immunity against both Gram-negative and Gram-positive bacteria without inducing adverse inflammatory cytokine due to IL-6.

A single-dose cytomegalovirus-based vaccine encoding tetanus toxin fragment C induces sustained levels of protective tetanus toxin antibodies in mice.

PubMed

Tierney, Rob; Nakai, Toru; Parkins, Christopher J; Caposio, Patrizia; Fairweather, Neil F; Sesardic, Dorothea; Jarvis, Michael A

2012-04-26

The current commercially available vaccine used to prevent tetanus disease following infection with the anaerobic bacterium Clostridium tetani is safe and effective. However, tetanus remains a major source of mortality in developing countries. In 2008, neonatal tetanus was estimated to have caused >59,000 deaths, accounting for 1% of worldwide infant mortality, primarily in poorer nations. The cost of multiple vaccine doses administered by injection necessary to achieve protective levels of anti-tetanus toxoid antibodies is the primary reason for low vaccine coverage. Herein, we show that a novel vaccine strategy using a cytomegalovirus (CMV)-based vaccine platform induces protective levels of anti-tetanus antibodies that are durable (lasting >13 months) in mice following only a single dose. This study demonstrates the ability of a 'single-dose' CMV-based vaccine strategy to induce durable protection, and supports the potential for a tetanus vaccine based on CMV to impact the incidence of tetanus in developing countries. Copyright © 2012 Elsevier Ltd. All rights reserved.

Protective efficacy of Zika vaccine in AG129 mouse model

PubMed Central

Sumathy, K.; Kulkarni, Bharathi; Gondu, Ravi Kumar; Ponnuru, Sampath Kumar; Bonguram, Nagaraju; Eligeti, Rakesh; Gadiyaram, Sindhuja; Praturi, Usha; Chougule, Bhushan; Karunakaran, Latha; Ella, Krishna M.

2017-01-01

Zika virus (ZIKV) is a mosquito-borne flavivirus that causes asymptomatic infection or presents only mild symptoms in majority of those infected. However, vaccination for ZIKV is a public health priority due to serious congenital and neuropathological abnormalities observed as a sequelae of the virus infection in the recent epidemics. We have developed an inactivated virus vaccine with the African MR 766 strain. Here we show that two doses of the vaccine provided 100% efficacy against mortality and disease following challenge with homotypic MR 766 and the heterotypic FSS 13025 ZIKV strains in the Type I and Type II interferon deficient AG129 mice. Two doses of the vaccine elicited high titer of neutralizing antibodies in Balb/c mice, and the vaccine antisera conferred protection against virus challenge in passively immunized mice. The studies were useful to rationalize vaccine doses for protective efficacy. Furthermore, the vaccine antisera neutralized the homotypic and heterotypic ZIKV strains in vitro with equivalent efficiency. Our study suggests a single ZIKV serotype, and that the development of an effective vaccine may not be limited by the choice of virus strain. PMID:28401907

Protective efficacy of Zika vaccine in AG129 mouse model.

PubMed

Sumathy, K; Kulkarni, Bharathi; Gondu, Ravi Kumar; Ponnuru, Sampath Kumar; Bonguram, Nagaraju; Eligeti, Rakesh; Gadiyaram, Sindhuja; Praturi, Usha; Chougule, Bhushan; Karunakaran, Latha; Ella, Krishna M

2017-04-12

Zika virus (ZIKV) is a mosquito-borne flavivirus that causes asymptomatic infection or presents only mild symptoms in majority of those infected. However, vaccination for ZIKV is a public health priority due to serious congenital and neuropathological abnormalities observed as a sequelae of the virus infection in the recent epidemics. We have developed an inactivated virus vaccine with the African MR 766 strain. Here we show that two doses of the vaccine provided 100% efficacy against mortality and disease following challenge with homotypic MR 766 and the heterotypic FSS 13025 ZIKV strains in the Type I and Type II interferon deficient AG129 mice. Two doses of the vaccine elicited high titer of neutralizing antibodies in Balb/c mice, and the vaccine antisera conferred protection against virus challenge in passively immunized mice. The studies were useful to rationalize vaccine doses for protective efficacy. Furthermore, the vaccine antisera neutralized the homotypic and heterotypic ZIKV strains in vitro with equivalent efficiency. Our study suggests a single ZIKV serotype, and that the development of an effective vaccine may not be limited by the choice of virus strain.

A VLP-based vaccine targeting domain III of the West Nile virus E protein protects from lethal infection in mice.

PubMed

Spohn, Gunther; Jennings, Gary T; Martina, Byron Ee; Keller, Iris; Beck, Markus; Pumpens, Paul; Osterhaus, Albert Dme; Bachmann, Martin F

2010-07-06

Since its first appearance in the USA in 1999, West Nile virus (WNV) has spread in the Western hemisphere and continues to represent an important public health concern. In the absence of effective treatment, there is a medical need for the development of a safe and efficient vaccine. Live attenuated WNV vaccines have shown promise in preclinical and clinical studies but might carry inherent risks due to the possibility of reversion to more virulent forms. Subunit vaccines based on the large envelope (E) glycoprotein of WNV have therefore been explored as an alternative approach. Although these vaccines were shown to protect from disease in animal models, multiple injections and/or strong adjuvants were required to reach efficacy, underscoring the need for more immunogenic, yet safe DIII-based vaccines. We produced a conjugate vaccine against WNV consisting of recombinantly expressed domain III (DIII) of the E glycoprotein chemically cross-linked to virus-like particles derived from the recently discovered bacteriophage AP205. In contrast to isolated DIII protein, which required three administrations to induce detectable antibody titers in mice, high titers of DIII-specific antibodies were induced after a single injection of the conjugate vaccine. These antibodies were able to neutralize the virus in vitro and provided partial protection from a challenge with a lethal dose of WNV. Three injections of the vaccine induced high titers of virus-neutralizing antibodies, and completely protected mice from WNV infection. The immunogenicity of DIII can be strongly enhanced by conjugation to virus-like particles of the bacteriophage AP205. The superior immunogenicity of the conjugate vaccine with respect to other DIII-based subunit vaccines, its anticipated favourable safety profile and low production costs highlight its potential as an efficacious and cost-effective prophylaxis against WNV.

Outer Membrane Vesicle Vaccines from Biosafe Surrogates Prevent Acute Lethal Glanders in Mice

PubMed Central

Khan, Mohammad S. R.; Chirakul, Sunisa; Schweizer, Herbert P.; Tuanyok, Apichai

2018-01-01

Burkholderia mallei is a host-adapted Gram-negative mammalian pathogen that causes the severe disease glanders. Glanders can manifest as a rapid acute progression or a chronic debilitating syndrome primarily affecting solipeds and humans in close association with infected animals. In USA, B. mallei is classified as one of the most important bacterial biothreat agents. Presently, there is no licensed glanders vaccine available for humans or animals. In this work, outer membrane vesicles (OMVs) were isolated from three attenuated biosafe bacterial strains, Burkholderia pseudomallei Bp82, B. thailandensis E555, and B. thailandensis TxDOH and used to vaccinate mice. B. thailandensis OMVs induced significantly higher antibody responses that were investigated. B. mallei specific serum antibody responses were of higher magnitude in mice vaccinated with B. thailandensis OMVs compared to levels in mice vaccinated with B. pseudomallei OMVs. OMVs derived from biosafe strains protected mice from acute lethal glanders with vesicles from the two B. thailandensis strains affording significant protection (>90%) up to 35 days post-infection with some up to 60 days. Organ loads from 35-day survivors indicated bacteria colonization of the lungs, liver, and spleen while those from 60 days had high CFUs in the spleens. The highest antibody producing vaccine (B. thailandensis E555 OMVs) also protected C57BL/6 mice from acute inhalational glanders with evidence of full protection. PMID:29320408

Tetanus vaccination with a dissolving microneedle patch confers protective immune responses in pregnancy.

PubMed

Esser, E Stein; Romanyuk, AndreyA; Vassilieva, Elena V; Jacob, Joshy; Prausnitz, Mark R; Compans, Richard W; Skountzou, Ioanna

2016-08-28

Maternal and neonatal tetanus claim tens of thousands lives every year in developing countries, but could be prevented by hygienic practices and improved immunization of pregnant women. This study tested the hypothesis that skin vaccination can overcome the immunologically transformed state of pregnancy and enhance protective immunity to tetanus in mothers and their newborns. To achieve this goal, we developed microneedle patches (MNPs) that efficiently delivered unadjuvanted tetanus toxoid to skin of pregnant mice and demonstrated that this route induced superior immune responses in female mice conferring 100% survival to tetanus toxin challenge when compared to intramuscular vaccination. Mice born to MNP-vaccinated mothers showed detectable tetanus-specific IgG antibodies up to 12weeks of age and complete protection to tetanus toxin challenge up at 6weeks of age. In contrast, none of the 6-week old mice born to intramuscularly vaccinated mothers survived challenge. Although pregnant mice vaccinated with unadjuvanted tetanus toxoid had 30% lower IgG and IgG1 titers than mice vaccinated intramuscularly with Alum®-adjuvanted tetanus toxoid vaccine, IgG2a titers and antibody affinity maturation were similar between these groups. We conclude that skin immunization with MNPs containing unadjuvanted tetanus toxoid can confer potent protective efficacy to mothers and their offspring using a delivery method well suited for expanding vaccination coverage in developing countries. Copyright © 2016 Elsevier B.V. All rights reserved.

Protection against murine potomac horse fever by an inactivated Ehrlichia risticii vaccine.

PubMed

Rikihisa, Y

1991-05-01

Ehrlichia risticii propagated in a murine macrophage cell line were freed from the host cell by hypotonic lysis of the infected cells. The cell-free ehrlichiae were inactivated with beta-propiolactone and combined or not combined with polymyxin-B. The vaccines were administered to mice with Quil-A (saponin) as an adjuvant twice at 2 to 3 week intervals and the mice were challenged with live E. risticii 2 to 3 weeks after the last vaccination. With or without the addition of polymyxin-B, the vaccine preparations protected mice from developing clinical signs and gross pathologic changes such as thymic atrophy, splenomegaly, and increase in whole intestinal weight. Mice vaccinated with or without polymyxin-B developed high titer IgG antibody against E. risticii before and after the challenge with live E. risticii. Spleen lymphocyte proliferative response assay at 11 days post challenge revealed that with polymyxin-B a higher lymphocyte proliferation occurred as compared with that of the mice which received polymyxin-B-free vaccine. Spleen lymphocytes of the placebo (polymyxin-B and Quil-A) pretreated/challenged mice showed no proliferative activity. Western blot analysis revealed that vaccinated mice reacted mainly with 110, 57 and 33 kDa antigen bands before and after challenge. The placebo (polymyxin-B and Quil-A)/challenged mice showed a very weak response to ehrlichial antigens at day 10 to 11 post challenge. Comparison with inactivated Renografin-purified E. risticii or 0.25% SDS-insoluble fraction of E. risticii with the inactivated host cell-free vaccine revealed no increased protection. These results indicate that inactivated host cell-free E. risticii can protect mice from murine Potomac horse fever. The presence of polymyxin-B appeared to be not harmful but rather beneficial for lymphocyte proliferation response upon challenge with live E. risticii.

Evaluation of protective effect of multiantigenic DNA vaccine encoding MIC3 and ROP18 antigen segments of Toxoplasma gondii in mice.

PubMed

Qu, Daofeng; Han, Jianzhong; Du, Aifang

2013-07-01

The high incidence and severe damage caused by Toxoplasma gondii infection clearly indicates the need for the development of a vaccine. In this study, we evaluated the immune responses and protection against toxoplasmosis by immunizing ICR mice with a multiantigenic DNA vaccine. To develop the multiantigenic vaccine, two T. gondii antigens, MIC3 and ROP18, selected on the basis of previous studies were chosen. ICR mice were immunized subcutaneously with PBS, empty pcDNA3.1 vector, pMIC3, pROP18, and pROP18-MIC3, respectively. The results of lymphocyte proliferation assay, cytokine, and antibody determinations showed that mice immunized with pROP18-MIC3 elicited stronger humoral and Th1-type cellular immune responses than those immunized with single-gene plasmids, empty plasmid, or phosphate-buffered saline. After a lethal challenge with the highly virulent T. gondii RH strain, a prolonged survival time in pROP18-MIC3-immunized mice was observed in comparison to control groups. Our study indicates that the introduction of multiantigenic DNA vaccine is more powerful and efficient than single-gene vaccine, and deserves further evaluation and development.

A DNA vaccine for Crimean-Congo hemorrhagic fever protects against disease and death in two lethal mouse models

PubMed Central

Fitzpatrick, Collin J.; Suschak, John J.; Richards, Michelle J.; Badger, Catherine V.; Six, Carolyn M.; Martin, Jacqueline D.; Hannaman, Drew; Zivcec, Marko; Bergeron, Eric; Koehler, Jeffrey W.; Schmaljohn, Connie S.

2017-01-01

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus capable of causing a severe hemorrhagic fever disease in humans. There are currently no licensed vaccines to prevent CCHFV-associated disease. We developed a DNA vaccine expressing the M-segment glycoprotein precursor gene of CCHFV and assessed its immunogenicity and protective efficacy in two lethal mouse models of disease: type I interferon receptor knockout (IFNAR-/-) mice; and a novel transiently immune suppressed (IS) mouse model. Vaccination of mice by muscle electroporation of the M-segment DNA vaccine elicited strong antigen-specific humoral immune responses with neutralizing titers after three vaccinations in both IFNAR-/- and IS mouse models. To compare the protective efficacy of the vaccine in the two models, groups of vaccinated mice (7–10 per group) were intraperitoneally (IP) challenged with a lethal dose of CCHFV strain IbAr 10200. Weight loss was markedly reduced in CCHFV DNA-vaccinated mice as compared to controls. Furthermore, whereas all vector-control vaccinated mice succumbed to disease by day 5, the DNA vaccine protected >60% of the animals from lethal disease. Mice from both models developed comparable levels of antibodies, but the IS mice had a more balanced Th1/Th2 response to vaccination. There were no statistical differences in the protective efficacies of the vaccine in the two models. Our results provide the first comparison of these two mouse models for assessing a vaccine against CCHFV and offer supportive data indicating that a DNA vaccine expressing the glycoprotein genes of CCHFV elicits protective immunity against CCHFV. PMID:28922426

A DNA vaccine for Crimean-Congo hemorrhagic fever protects against disease and death in two lethal mouse models.

PubMed

Garrison, Aura R; Shoemaker, Charles J; Golden, Joseph W; Fitzpatrick, Collin J; Suschak, John J; Richards, Michelle J; Badger, Catherine V; Six, Carolyn M; Martin, Jacqueline D; Hannaman, Drew; Zivcec, Marko; Bergeron, Eric; Koehler, Jeffrey W; Schmaljohn, Connie S

2017-09-01

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus capable of causing a severe hemorrhagic fever disease in humans. There are currently no licensed vaccines to prevent CCHFV-associated disease. We developed a DNA vaccine expressing the M-segment glycoprotein precursor gene of CCHFV and assessed its immunogenicity and protective efficacy in two lethal mouse models of disease: type I interferon receptor knockout (IFNAR-/-) mice; and a novel transiently immune suppressed (IS) mouse model. Vaccination of mice by muscle electroporation of the M-segment DNA vaccine elicited strong antigen-specific humoral immune responses with neutralizing titers after three vaccinations in both IFNAR-/- and IS mouse models. To compare the protective efficacy of the vaccine in the two models, groups of vaccinated mice (7-10 per group) were intraperitoneally (IP) challenged with a lethal dose of CCHFV strain IbAr 10200. Weight loss was markedly reduced in CCHFV DNA-vaccinated mice as compared to controls. Furthermore, whereas all vector-control vaccinated mice succumbed to disease by day 5, the DNA vaccine protected >60% of the animals from lethal disease. Mice from both models developed comparable levels of antibodies, but the IS mice had a more balanced Th1/Th2 response to vaccination. There were no statistical differences in the protective efficacies of the vaccine in the two models. Our results provide the first comparison of these two mouse models for assessing a vaccine against CCHFV and offer supportive data indicating that a DNA vaccine expressing the glycoprotein genes of CCHFV elicits protective immunity against CCHFV.

Brucella suis strain 2 vaccine is safe and protective against heterologous Brucella spp. infections.

PubMed

Zhu, Liangquan; Feng, Yu; Zhang, Ge; Jiang, Hui; Zhang, Zhen; Wang, Nan; Ding, Jiabo; Suo, Xun

2016-01-12

Brucellosis is a wide spread zoonotic disease that causes abortion and infertility in mammals and leads to debilitating, febrile illness in humans. Brucella abortus, Brucella melitensis and Brucella suis are the major pathogenic species to humans. Vaccination with live attenuated B. suis strain 2 (S2) vaccine is an essential and critical component in the control of brucellosis in China. The S2 vaccine is very effective in preventing brucellosis in goats, sheep, cattle and swine. However, there are still debates outside of China whether the S2 vaccine is able to provide protection against heterologous virulent Brucella species. We investigated the residual virulence, immunogenicity and protective efficacy of the S2 vaccine in BALB/c mice by determining bacteria persistence in spleen, serum antibody response, cellular immune response and protection against a heterologous virulent challenge. The S2 vaccine was of low virulence as there were no bacteria recovered in spleen four weeks post vaccination. The vaccinated mice developed Brucella-specific IgG in 2-3 weeks, and a burst production of IFN-γ at one week as well as a two-fold increase in TNF-α production. The S2 vaccine protected mice from a virulent challenge by B. melitensis M28, B. abortus 2308 and B. suis S1330, and the S2 vaccinated mice did not develop any clinical signs or tissue damage. Our study demonstrated that the S2 vaccine is of low virulence, stimulates good humoral and cellular immunity and protects animals against infection by heterologous, virulent Brucella species. Copyright © 2015 Elsevier Ltd. All rights reserved.

Enhanced protection against Ebola virus mediated by an improved adenovirus-based vaccine.

PubMed

Richardson, Jason S; Yao, Michel K; Tran, Kaylie N; Croyle, Maria A; Strong, James E; Feldmann, Heinz; Kobinger, Gary P

2009-01-01

The Ebola virus is transmitted by direct contact with bodily fluids of infected individuals, eliciting death rates as high as 90% among infected humans. Currently, replication defective adenovirus-based Ebola vaccine is being studied in a phase I clinical trial. Another Ebola vaccine, based on an attenuated vesicular stomatitis virus has shown efficacy in post-exposure treatment of nonhuman primates to Ebola infection. In this report, we modified the common recombinant adenovirus serotype 5-based Ebola vaccine expressing the wild-type ZEBOV glycoprotein sequence from a CMV promoter (Ad-CMVZGP). The immune response elicited by this improved expression cassette vector (Ad-CAGoptZGP) and its ability to afford protection against lethal ZEBOV challenge in mice was compared to the standard Ad-CMVZGP vector. Ad-CMVZGP was previously shown to protect mice, guinea pigs and nonhuman primates from an otherwise lethal challenge of Zaire ebolavirus. The antigenic expression cassette of this vector was improved through codon optimization, inclusion of a consensus Kozak sequence and reconfiguration of a CAG promoter (Ad-CAGoptZGP). Expression of GP from Ad-CAGoptZGP was substantially higher than from Ad-CMVZGP. Ad-CAGoptZGP significantly improved T and B cell responses at doses 10 to 100-fold lower than that needed with Ad-CMVZGP. Additionally, Ad-CAGoptZGP afforded full protections in mice against lethal challenge at a dose 100 times lower than the dose required for Ad-CMVZGP. Finally, Ad-CAGoptZGP induced full protection to mice when given 30 minutes post-challenge. We describe an improved adenovirus-based Ebola vaccine capable of affording post-exposure protection against lethal challenge in mice. The molecular modifications of the new improved vaccine also translated in the induction of significantly enhanced immune responses and complete protection at a dose 100 times lower than with the previous generation adenovirus-based Ebola vaccine. Understanding and improving the

A clinically applicable adjuvant for an atherosclerosis vaccine in mice.

PubMed

Kobiyama, Kouji; Vassallo, Melanie; Mitzi, Jessica; Winkels, Holger; Pei, Hong; Kimura, Takayuki; Miller, Jacqueline; Wolf, Dennis; Ley, Klaus

2018-06-22

Vaccination with MHC-II-restricted peptides from Apolipoprotein B (ApoB) with complete and incomplete Freund's adjuvant (CFA/IFA) is known to protect mice from atherosclerosis. This vaccination induces antigen-specific IgG1 and IgG2c antibody responses and a robust CD4 T cell response in lymph nodes. However, CFA/IFA cannot be used in humans. To find a clinically applicable adjuvant, we tested the effect of vaccinating Apoe-deficient mice with ApoB peptide P6 (TGAYSNASSTESASY). In a broad screening experiment, Addavax, a squalene oil similar to MF59, was the only adjuvant that showed similar efficacy as CFA/IFA. This was confirmed in a confirmation experiment for both the aortic arch and whole aorta analyzed by en face analysis after atherosclerotic lesion staining. Mechanistically, restimulated peritoneal cells from mice immunized with P6 in Addavax released significant amounts of IL-10. Unlike P6 in CFA/IFA, vaccination with P6 in Addavax did not induce any detectable IgG1 or IgG2c antibodies to P6. These data suggest that squalene-based adjuvants such as MF59 are good candidate adjuvants for developing a clinically effective atherosclerosis vaccine. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Vaccination with Replication Deficient Adenovectors Encoding YF-17D Antigens Induces Long-Lasting Protection from Severe Yellow Fever Virus Infection in Mice.

PubMed

Bassi, Maria R; Larsen, Mads A B; Kongsgaard, Michael; Rasmussen, Michael; Buus, Søren; Stryhn, Anette; Thomsen, Allan R; Christensen, Jan P

2016-02-01

The live attenuated yellow fever vaccine (YF-17D) has been successfully used for more than 70 years. It is generally considered a safe vaccine, however, recent reports of serious adverse events following vaccination have raised concerns and led to suggestions that even safer YF vaccines should be developed. Replication deficient adenoviruses (Ad) have been widely evaluated as recombinant vectors, particularly in the context of prophylactic vaccination against viral infections in which induction of CD8+ T-cell mediated immunity is crucial, but potent antibody responses may also be elicited using these vectors. In this study, we present two adenobased vectors targeting non-structural and structural YF antigens and characterize their immunological properties. We report that a single immunization with an Ad-vector encoding the non-structural protein 3 from YF-17D could elicit a strong CD8+ T-cell response, which afforded a high degree of protection from subsequent intracranial challenge of vaccinated mice. However, full protection was only observed using a vector encoding the structural proteins from YF-17D. This vector elicited virus-specific CD8+ T cells as well as neutralizing antibodies, and both components were shown to be important for protection thus mimicking the situation recently uncovered in YF-17D vaccinated mice. Considering that Ad-vectors are very safe, easy to produce and highly immunogenic in humans, our data indicate that a replication deficient adenovector-based YF vaccine may represent a safe and efficient alternative to the classical live attenuated YF vaccine and should be further tested.

A recombinant virus vaccine that protects against both Chikungunya and Zika virus infections.

PubMed

Chattopadhyay, Anasuya; Aguilar, Patricia V; Bopp, Nathen E; Yarovinsky, Timur O; Weaver, Scott C; Rose, John K

2018-06-22

Chikungunya virus (CHIKV) and Zika virus (ZIKV) have recently expanded their range in the world and caused serious and widespread outbreaks of near pandemic proportions. There are no licensed vaccines that protect against these co-circulating viruses that are transmitted by invasive mosquito vectors. We report here on the development of a single-dose, bivalent experimental vaccine for CHIKV and ZIKV. This vaccine is based on a chimeric vesicular stomatitis virus (VSV) that expresses the CHIKV envelope polyprotein (E3-E2-6K-E1) in place of the VSV glycoprotein (G) and also expresses the membrane-envelope (ME) glycoproteins of ZIKV. This vaccine induced neutralizing antibody responses to both CHIKV and ZIKV in wild-type mice and in interferon receptor-deficient A129 mice, animal models for CHIKV and ZIKV infection. A single vaccination of A129 mice with the vector protected these mice against infection with both CHIKV and ZIKV. Our single-dose vaccine could provide durable, low-cost protection against both CHIKV and ZIKV for people traveling to or living in areas where both viruses are circulating, which include most tropical regions in the world. Copyright © 2018. Published by Elsevier Ltd.

Protective efficacy of a Toxoplasma gondii rhoptry protein 13 plasmid DNA vaccine in mice.

PubMed

Wang, Pei-Yuan; Yuan, Zi-Guo; Petersen, Eskild; Li, Jie; Zhang, Xiu-Xiang; Li, Xiu-Zhen; Li, Hao-Xin; Lv, Zhi-Cheng; Cheng, Tian; Ren, Di; Yang, Gui-Lian; Lin, Rui-Qing; Zhu, Xing-Quan

2012-12-01

Toxoplasma gondii is an obligate intracellular parasite infecting humans and other warm-blooded animals, resulting in serious public health problems and economic losses worldwide. Rhoptries are involved in T. gondii invasion and host cell interaction and have been implicated as important virulence factors. In the present study, a DNA vaccine expressing rhoptry protein 13 (ROP13) of T. gondii inserted into eukaryotic expression vector pVAX I was constructed, and the immune protection it induced in Kunming mice was evaluated. Kunming mice were immunized intramuscularly with pVAX-ROP13 and/or with interleukin-18 (IL-18). Then, we evaluated the immune response using a lymphoproliferative assay, cytokine and antibody measurements, and the survival times of mice challenged with the virulent T. gondii RH strain (type I) and the cyst-forming PRU strain (type II). The results showed that pVAX-ROP13 alone or with pVAX/IL-18 induced a high level of specific anti-T. gondii antibodies and specific lymphocyte proliferative responses. Coinjection of pVAX/IL-18 significantly increased the production of gamma interferon (IFN-γ), IL-2, IL-4, and IL-10. Further, challenge experiments showed that coimmunization of pVAX-ROP13 with pVAX/IL-18 significantly (P < 0.05) increased survival time (32.3 ± 2.7 days) compared with pVAX-ROP13 alone (24.9 ± 2.3 days). Immunized mice challenged with T. gondii cysts (strain PRU) had a significant reduction in the number of brain cysts, suggesting that ROP13 could trigger a strong humoral and cellular response against T. gondii cyst infection and that it is a potential vaccine candidate against toxoplasmosis, which provided the foundation for further development of effective vaccines against T. gondii.

Protective immunity in mice achieved with dry powder formulation and alternative delivery of plague F1-V vaccine.

PubMed

Huang, Joanne; D'Souza, Ajit J; Alarcon, Jason B; Mikszta, John A; Ford, Brandi M; Ferriter, Matthew S; Evans, Michelle; Stewart, Todd; Amemiya, Kei; Ulrich, Robert G; Sullivan, Vincent J

2009-05-01

The potential use of Yersinia pestis as a bioterror agent is a great concern. Development of a stable powder vaccine against Y. pestis and administration of the vaccine by minimally invasive methods could provide an alternative to the traditional liquid formulation and intramuscular injection. We evaluated a spray-freeze-dried powder vaccine containing a recombinant F1-V fusion protein of Y. pestis for vaccination against plaque in a mouse model. Mice were immunized with reconstituted spray-freeze-dried F1-V powder via intramuscular injection, microneedle-based intradermal delivery, or noninvasive intranasal administration. By intramuscular injection, the reconstituted powder induced serum antibody responses and provided protection against lethal subcutaneous challenge with 1,000 50% lethal doses of Y. pestis at levels equivalent to those elicited by unprocessed liquid formulations (70 to 90% protection). The feasibility of intradermal and intranasal delivery of reconstituted powder F1-V vaccine was also demonstrated. Overall, microneedle-based intradermal delivery was shown to be similar in efficacy to intramuscular injection, while intranasal administration required an extra dose of vaccine to achieve similar protection. In addition, the results suggest that seroconversion against F1 may be a better predictor of protection against Y. pestis challenge than seroconversion against either F1-V or V. In summary, we demonstrate the preclinical feasibility of using a reconstituted powder F1-V formulation and microneedle-based intradermal delivery to provide protective immunity against plague in a mouse model. Intranasal delivery, while feasible, was less effective than injection in this study. The potential use of these alternative delivery methods and a powder vaccine formulation may result in substantial health and economic benefits.

Complete Protection against Pneumonic and Bubonic Plague after a Single Oral Vaccination.

PubMed

Derbise, Anne; Hanada, Yuri; Khalifé, Manal; Carniel, Elisabeth; Demeure, Christian E

2015-01-01

No efficient vaccine against plague is currently available. We previously showed that a genetically attenuated Yersinia pseudotuberculosis producing the Yersinia pestis F1 antigen was an efficient live oral vaccine against pneumonic plague. This candidate vaccine however failed to confer full protection against bubonic plague and did not produce F1 stably. The caf operon encoding F1 was inserted into the chromosome of a genetically attenuated Y. pseudotuberculosis, yielding the VTnF1 strain, which stably produced the F1 capsule. Given orally to mice, VTnF1 persisted two weeks in the mouse gut and induced a high humoral response targeting both F1 and other Y. pestis antigens. The strong cellular response elicited was directed mostly against targets other than F1, but also against F1. It involved cells with a Th1-Th17 effector profile, producing IFNγ, IL-17, and IL-10. A single oral dose (108 CFU) of VTnF1 conferred 100% protection against pneumonic plague using a high-dose challenge (3,300 LD50) caused by the fully virulent Y. pestis CO92. Moreover, vaccination protected 100% of mice from bubonic plague caused by a challenge with 100 LD50 Y. pestis and 93% against a high-dose infection (10,000 LD50). Protection involved fast-acting mechanisms controlling Y. pestis spread out of the injection site, and the protection provided was long-lasting, with 93% and 50% of mice surviving bubonic and pneumonic plague respectively, six months after vaccination. Vaccinated mice also survived bubonic and pneumonic plague caused by a high-dose of non-encapsulated (F1-) Y. pestis. VTnF1 is an easy-to-produce, genetically stable plague vaccine candidate, providing a highly efficient and long-lasting protection against both bubonic and pneumonic plague caused by wild type or un-encapsulated (F1-negative) Y. pestis. To our knowledge, VTnF1 is the only plague vaccine ever reported that could provide high and durable protection against the two forms of plague after a single oral

A novel inactivated enterovirus 71 vaccine can elicit cross-protective immunity against coxsackievirus A16 in mice.

PubMed

Yang, Lisheng; Liu, Yajing; Li, Shuxuan; Zhao, Huan; Lin, Qiaona; Yu, Hai; Huang, Xiumin; Zheng, Qingbing; Cheng, Tong; Xia, Ningshao

2016-11-21

Hand, foot, and mouth disease (HFMD) is a highly contagious disease that mainly affects infants and children. Enterovirus 71 (EV71) and coxsackievirus A16 (CA16) are the major pathogens of HFMD. Two EV71 vaccines were recently licensed in China and the administration of the EV71 vaccines is believed to significantly reduce the number of HFMD-related severe or fatal cases. However, a monovalent EV71 vaccine cannot cross-protect against CA16 infection, this may result in that it cannot effectively control the overall HFMD epidemic. In this study, a chimeric EV71, whose VP1/210-225 epitope was replaced by that of CA16, was constructed using a reverse genetics technique to produce a candidate EV71/CA16 bivalent vaccine strain. The chimeric EV71 was infectious and showed similar growth characteristics as its parental strain. The replacement of the VP1/210-225 epitope did not significantly affect the antigenicity and immunogenicity of EV71. More importantly, the chimeric EV71 could induce protective immunity against both EV71 and CA16, and protect neonatal mice against either EV71 or CA16 lethal infections, the chimeric EV71 constructed in this study was shown to be a feasible and promising candidate bivalent vaccine against both EV71 and CA16. The construction of a chimeric enterovirus also provides an alternative platform for broad-spectrum HFMD vaccines development. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Protective Effects of the A/ZJU01/ PR8/2013 Split H7N9 Avian Influenza Vaccine Against Highly Pathogenic H7N9 in BALB/c Mice.

PubMed

Wu, Xiao-Xin; Deng, Xi-Long; Yu, Dong-Shan; Yao, Wei; Ou, Hui-Lin; Weng, Tian-Hao; Hu, Chen-Yu; Hu, Feng-Yu; Wu, Nan-Ping; Yao, Hangping; Zhang, Fu-Chun; Li, Lan-Juan

2018-01-01

Since the first case of novel H7N9 infection was reported, China has experienced five epidemics of H7N9. During the fifth wave, a highly pathogenic H7N9 strain emerged. In order to assess whether the H7N9 vaccine based on A/Zhejiang/DTID-ZJU01/2013(H7N9) was effective in protecting against highly pathogenic H7N9, we conducted this study. Groups of mice were immunized twice by intraperitoneal injection with 500 µl of either split vaccine alone or MF59-adjuvanted vaccine. Serum was collected 2 weeks after the second vaccine booster. The hemagglutinin inhibition test was conducted on vaccine seed and highly pathogenic H7N9 to evaluate the neutralization of highly pathogenic H7N9. We also immunized mice and challenged them with highly pathogenic H7N9. Mice were observed for illness, weight loss, and death at 1 week and 2 weeks post-infection. Then, the mice were sacrificed and lungs were removed. Antibody responses were assessed and pathological changes in the lung tissue were evaluated. The ability of serum to neutralize highly pathogenic H7N9 was reduced. In mice, highly pathogenic H7N9 was more virulent than A/Zhejiang/DTID-ZJU01/2013(H7N9). After challenge with highly pathogenic H7N9, all mice died while mice challenged with A/Zhejiang/DTID-ZJU01/2013(H7N9) all recovered. The A/ZJU01/PR8/2013 split H7N9 avian influenza vaccine was able to protect against infection with highly pathogenic H7N9 in mice, with or without MF59. Moreover, H7N9 vaccine adjuvanted with MF59 produced high antibody levels, which lead to better protection. The A/ZJU01/PR8/2013 split H7N9 avian influenza vaccine based on A/Zhejiang/DTID-ZJU01/2013(H7N9) is effective in protecting against highly pathogenic H7N9. H7N9 vaccine adjuvanted with MF59 offers better protection against infection with highly pathogenic H7N9. In order to make the H7N9 vaccine applicable to humans, further clinical trials are required to evaluate MF59 adjuvanted vaccine. Meanwhile, the vaccine strain should be updated

Increased Protection against Pneumococcal Disease by Mucosal Administration of Conjugate Vaccine plus Interleukin-12

PubMed Central

Lynch, Joyce M.; Briles, David E.; Metzger, Dennis W.

2003-01-01

Streptococcus pneumoniae is a common cause of respiratory tract infections, its main entry route being the nasal mucosa. The recent development of pneumococcal polysaccharide conjugate vaccines has led to a dramatic improvement in protection against invasive disease in infants and children, but these vaccines have been found to be only 50 to 60% protective against bacterial carriage. In this study, we investigated the efficacy of intranasal (i.n.) conjugate vaccine delivery using interleukin-12 (IL-12) as a mucosal adjuvant. Immunized mice treated with IL-12 demonstrated increased expression of lung and splenic gamma interferon and IL-10 mRNAs; high levels of antibody, particularly serum immunoglobulin G2a (IgG2a) and respiratory IgA; and significantly increased opsonic activity. After intraperitoneal challenge with type 3 pneumococci, there was 75% survival of i.n. vaccinated mice compared to 0% survival of unvaccinated mice. In addition, after i.n. challenge with type 14 pneumococci, vaccinated mice possessed fewer bacterial colonies in the upper respiratory tract than unvaccinated mice. However, no significant difference in type 14 carriage was observed between vaccinated and unvaccinated groups following intramuscular vaccination, the typical route of vaccination in humans. Using mice with a genetic disruption in IgA expression, it was found that pneumococcus-specific IgA played a significant role in the clearance of bacteria from the upper respiratory tract. We conclude that i.n vaccination in the presence of IL-12 is able to enhance systemic and mucosal immune responses to pneumococci and efficiently protect against both invasive infection and bacterial carriage. PMID:12874361

A boosting skin vaccination with dissolving microneedle patch encapsulating M2e vaccine broadens the protective efficacy of conventional influenza vaccines.

PubMed

Zhu, Wandi; Pewin, Winston; Wang, Chao; Luo, Yuan; Gonzalez, Gilbert X; Mohan, Teena; Prausnitz, Mark R; Wang, Bao-Zhong

2017-09-10

The biodegradable microneedle patch (MNP) is a novel technology for vaccine delivery that could improve the immunogenicity of vaccines. To broaden the protective efficiency of conventional influenza vaccines, a new 4M2e-tFliC fusion protein construct containing M2e sequences from different subtypes was generated. Purified fusion protein was encapsulate into MNPs with a biocompatible polymer for use as a boosting vaccine. The results demonstrated that mice receiving a conventional inactivated vaccine followed by a skin-applied dissolving 4M2e-tFliC MNP boost could better maintain the humoral antibody response than that by the conventional vaccine-prime alone. Compared with an intramuscular injection boost, mice receiving the MNP boost showed significantly enhanced cellular immune responses, hemagglutination-inhibition (HAI) titers, and neutralization titers. Increased frequency of antigen-specific plasma cells and long-lived bone marrow plasma cells was detected in the MNP boosted group as well, indicating that skin vaccination with 4M2e-tFliC facilitated a long-term antibody-mediated immunity. The 4M2e-tFliC MNP-boosted group also possessed enhanced protection against high lethal dose challenges against homologous A/PR/8/34 and A/Aichi/2/68 viruses and protection for a majority of immunized mice against a heterologous A/California/07/2009 H1N1 virus. High levels of M2e specific immune responses were observed in the 4M2e-tFliC MNP-boosted group as well. These results demonstrate that a skin-applied 4M2e-tFliC MNP boosting immunization to seasonal vaccine recipients may be a rapid approach for increasing the protective efficacy of seasonal vaccines in response to a significant drift seen in circulating viruses. The results also provide a new perspective for future exploration of universal influenza vaccines. Copyright © 2017 Elsevier B.V. All rights reserved.

A cell culture-derived whole virus influenza A vaccine based on magnetic sulfated cellulose particles confers protection in mice against lethal influenza A virus infection.

PubMed

Pieler, Michael M; Frentzel, Sarah; Bruder, Dunja; Wolff, Michael W; Reichl, Udo

2016-12-07

Downstream processing and formulation of viral vaccines employs a large number of different unit operations to achieve the desired product qualities. The complexity of individual process steps involved, the need for time consuming studies towards the optimization of virus yields, and very high requirements regarding potency and safety of vaccines results typically in long lead times for the establishment of new processes. To overcome such obstacles, to enable fast screening of potential vaccine candidates, and to explore options for production of low cost veterinary vaccines a new platform for whole virus particle purification and formulation based on magnetic particles has been established. Proof of concept was carried out with influenza A virus particles produced in suspension Madin Darby canine kidney (MDCK) cells. The clarified, inactivated, concentrated, and diafiltered virus particles were bound to magnetic sulfated cellulose particles (MSCP), and directly injected into mice for immunization including positive and negative controls. We show here, that in contrast to the mock-immunized group, vaccination of mice with antigen-loaded MSCP (aMSCP) resulted in high anti-influenza A antibody responses and full protection against a lethal challenge with replication competent influenza A virus. Antiviral protection correlated with a 400-fold reduced number of influenza nucleoprotein gene copies in the lungs of aMSCP immunized mice compared to mock-treated animals, indicating the efficient induction of antiviral immunity by this novel approach. Thus, our data proved the use of MSCP for purification and formulation of the influenza vaccine to be fast and efficient, and to confer protection of mice against influenza A virus infection. Furthermore, the method proposed has the potential for fast purification of virus particles directly from bioreactor harvests with a minimum number of process steps towards formulation of low-cost veterinary vaccines, and for screening

Expression, purification, immunogenicity, and protective efficacy of a recombinant Tc24 antigen as a vaccine against Trypanosoma cruzi infection in mice.

PubMed

Martinez-Campos, Viridiana; Martinez-Vega, Pedro; Ramirez-Sierra, Maria Jesus; Rosado-Vallado, Miguel; Seid, Christopher A; Hudspeth, Elissa M; Wei, Junfei; Liu, Zhuyun; Kwityn, Cliff; Hammond, Molly; Ortega-López, Jaime; Zhan, Bin; Hotez, Peter J; Bottazzi, Maria Elena; Dumonteil, Eric

2015-08-26

The Tc24 calcium binding protein from the flagellar pocket of Trypanosoma cruzi is under evaluation as a candidate vaccine antigen against Chagas disease. Previously, a DNA vaccine encoding Tc24 was shown to be an effective vaccine (both as a preventive and therapeutic intervention) in mice and dogs, as evidenced by reductions in T. cruzi parasitemia and cardiac amastigotes, as well as reduced cardiac inflammation and increased host survival. Here we developed a suitable platform for the large scale production of recombinant Tc24 (rTc24) and show that when rTc24 is combined with a monophosphoryl-lipid A (MPLA) adjuvant, the formulated vaccine induces a Th1-biased immune response in mice, comprised of elevated IgG2a antibody levels and interferon-gamma levels from splenocytes, compared to controls. These immune responses also resulted in statistically significant decreased T. cruzi parasitemia and cardiac amastigotes, as well as increased survival following T. cruzi challenge infections, compared to controls. Partial protective efficacy was shown regardless of whether the antigen was expressed in Escherichia coli or in yeast (Pichia pastoris). While mouse vaccinations will require further modifications in order to optimize protective efficacy, such studies provide a basis for further evaluations of vaccines comprised of rTc24, together with alternative adjuvants and additional recombinant antigens. Copyright © 2015. Published by Elsevier Ltd.

Protective Efficacy of the Conserved NP, PB1, and M1 Proteins as Immunogens in DNA- and Vaccinia Virus-Based Universal Influenza A Virus Vaccines in Mice

PubMed Central

Wang, Wenling; Li, Renqing; Deng, Yao; Lu, Ning; Chen, Hong; Meng, Xin; Wang, Wen; Wang, Xiuping; Yan, Kexia; Qi, Xiangrong; Zhang, Xiangmin; Xin, Wei; Lu, Zhenhua; Li, Xueren; Bian, Tao; Gao, Yingying; Tan, Wenjie

2015-01-01

The conventional hemagglutinin (HA)- and neuraminidase (NA)-based influenza vaccines need to be updated most years and are ineffective if the glycoprotein HA of the vaccine strains is a mismatch with that of the epidemic strain. Universal vaccines targeting conserved viral components might provide cross-protection and thus complement and improve conventional vaccines. In this study, we generated DNA plasmids and recombinant vaccinia viruses expressing the conserved proteins nucleoprotein (NP), polymerase basic 1 (PB1), and matrix 1 (M1) from influenza virus strain A/Beijing/30/95 (H3N2). BALB/c mice were immunized intramuscularly with a single vaccine based on NP, PB1, or M1 alone or a combination vaccine based on all three antigens and were then challenged with lethal doses of the heterologous influenza virus strain A/PR/8/34 (H1N1). Vaccines based on NP, PB1, and M1 provided complete or partial protection against challenge with 1.7 50% lethal dose (LD50) of PR8 in mice. Of the three antigens, NP-based vaccines induced protection against 5 LD50 and 10 LD50 and thus exhibited the greatest protective effect. Universal influenza vaccines based on the combination of NP, PB1, and M1 induced a strong immune response and thus might be an alternative approach to addressing future influenza virus pandemics. PMID:25834017

Oral immunization of mice with live Pneumocystis murina protects against Pneumocystis pneumonia

PubMed Central

Samuelson, Derrick R.; de la Rua, Nicholas M.; Charles, Tysheena P.; Ruan, Sanbao; Taylor, Christopher M.; Blanchard, Eugene E.; Luo, Meng; Ramsay, Alistair J.; Shellito, Judd E.; Welsh, David A.

2016-01-01

Pneumocystis pneumonia is a major cause of morbidity and mortality in immunocompromised patients; particularly those infected with human immunodeficiency virus. In this study, we evaluated the potential of oral immunization with live Pneumocystis to elicit protection against respiratory infection with Pneumocystis murina. C57BL/6 mice vaccinated with live P. murina using a prime-boost vaccination strategy were protected from a subsequent lung challenge with P. murina at 2, 7, 14, and 28 days post infection even after CD4+ T cell depletion. Specifically, vaccinated immunocompetent mice had significantly faster clearance than unvaccinated immunocompetent mice and unvaccinated CD4-depleted mice remained persistently infected with P. murina. Vaccination also increased numbers of CD4+ T cells, CD8+ T cells, CD19+ B cells, and CD11b+ macrophages in the lungs following respiratory infection. In addition, levels of lung, serum, and fecal P. murina-specific IgG and IgA were increased in vaccinated animals. Further, administration of serum from vaccinated mice significantly reduced Pneumocystis lung burden in infected animals compared to control serum. We also found that the diversity of the intestinal microbial community was altered by oral immunization with P. murina. Our data demonstrate for the first time that an oral vaccination strategy prevents Pneumocystis infection. PMID:26864029

Oral administration of a Salmonella enterica-based vaccine expressing Bacillus anthracis protective antigen confers protection against aerosolized B. anthracis.

PubMed

Stokes, Margaret G M; Titball, Richard W; Neeson, Brendan N; Galen, James E; Walker, Nicola J; Stagg, Anthony J; Jenner, Dominic C; Thwaite, Joanne E; Nataro, James P; Baillie, Leslie W J; Atkins, Helen S

2007-04-01

Bacillus anthracis is the causative agent of anthrax, a disease that affects wildlife, livestock, and humans. Protection against anthrax is primarily afforded by immunity to the B. anthracis protective antigen (PA), particularly PA domains 4 and 1. To further the development of an orally delivered human vaccine for mass vaccination against anthrax, we produced Salmonella enterica serovar Typhimurium expressing full-length PA, PA domains 1 and 4, or PA domain 4 using codon-optimized PA DNA fused to the S. enterica serovar Typhi ClyA and under the control of the ompC promoter. Oral immunization of A/J mice with Salmonella expressing full-length PA protected five of six mice against a challenge with 10(5) CFU of aerosolized B. anthracis STI spores, whereas Salmonella expressing PA domains 1 and 4 provided only 25% protection (two of eight mice), and Salmonella expressing PA domain 4 or a Salmonella-only control afforded no measurable protection. However, a purified recombinant fusion protein of domains 1 and 4 provided 100% protection, and purified recombinant 4 provided protection in three of eight immunized mice. Thus, we demonstrate for the first time the efficacy of an oral S. enterica-based vaccine against aerosolized B. anthracis spores.

Liposomal gD Ectodomain (gD1-306) Vaccine Protects Against HSV2 Genital or Rectal Infection of Female and Male Mice

PubMed Central

Olson, K.; Macias, P.; Hutton, S.; Ernst, W. A.; Fujii, G.; Adler-Moore, J. P.

2009-01-01

Herpes simplex virus type 2 (HSV2) is the most common causative agent of genital herpes, with infection rates as high as 1 in 6 adults. The present studies were done to evaluate the efficacy of a liposomal HSV2 gD1-306 vaccine (L-gD1-306-HD) in an acute murine HSV2 infection model of intravaginal (female) or intrarectal (male or female) challenge. Two doses of L-gD1-306-HD containing 60μg gD1-306-HD and 15μg monophosphoryl lipid A (MPL) per dose provided protection against HSV2 intravaginal challenge (86-100% survival, P≤0.0003 vs control liposomes; P=0.06 vs L-gD1-306-HD without MPL). Both male and female mice (BALB/c and C57BL/6) immunized with L-gD1-306-HD/MPL were significantly protected against HSV2 intrarectal challenge, with higher survival rates compared to controls (71-100%, P≤0.007). L-gD1-306-HD/MPL also provided increased survival when compared to a liposomal peptide vaccine, L-gD264-285-HD/MPL (male BALB/c, P≤0.001; female BALB/c and male C57BL/6, P=0.06). Mice given L-gD1-306-HD/MPL also had minimal disease signs, reduced viral burden in their spinal cords and elevated neutralizing antibody titers in the females. The vaccine also stimulated gD1-306-HD specific splenocytes of both male and female mice with significantly elevated levels of IFN-γ compared to IL-4 (P≤0.01) indicating that there was an enhanced Th1 response. These results provide the first evidence that the L-gD1-306–HD vaccine can protect both male and female mice against intrarectal HSV2 challenge. PMID:19835825

Liposomal gD ectodomain (gD1-306) vaccine protects against HSV2 genital or rectal infection of female and male mice.

PubMed

Olson, K; Macias, P; Hutton, S; Ernst, W A; Fujii, G; Adler-Moore, J P

2009-12-11

Herpes simplex virus type 2 (HSV2) is the most common causative agent of genital herpes, with infection rates as high as 1 in 6 adults. The present studies were done to evaluate the efficacy of a liposomal HSV2 gD(1-306) vaccine (L-gD(1-306)-HD) in an acute murine HSV2 infection model of intravaginal (female) or intrarectal (male or female) challenge. Two doses of L-gD(1-306)-HD containing 60 microg gD(1-306)-HD and 15 microg monophosphoryl lipid A (MPL) per dose provided protection against HSV2 intravaginal challenge (86-100% survival, P< or =0.0003 vs. control liposomes; P=0.06 vs. L-gD(1-306)-HD without MPL). Both male and female mice (BALB/c and C57BL/6) immunized with L-gD(1-306)-HD/MPL were significantly protected against HSV2 intrarectal challenge, with higher survival rates compared to controls (71-100%, P< or =0.007). L-gD(1-306)-HD/MPL also provided increased survival when compared to a liposomal peptide vaccine, L-gD(264-285)-HD/MPL (male BALB/c, PMice given L-gD(1-306)-HD/MPL also had minimal disease signs, reduced viral burden in their spinal cords and elevated neutralizing antibody titers in the females. The vaccine also stimulated gD(1-306)-HD specific splenocytes of both male and female mice with significantly elevated levels of IFN-gamma compared to IL-4 (P< or =0.01) indicating that there was an enhanced Th1 response. These results provide the first evidence that the L-gD(1-306)-HD vaccine can protect both male and female mice against intrarectal HSV2 challenge.

Complete Protection against Pneumonic and Bubonic Plague after a Single Oral Vaccination

PubMed Central

Derbise, Anne; Hanada, Yuri; Khalifé, Manal; Carniel, Elisabeth; Demeure, Christian E.

2015-01-01

Background No efficient vaccine against plague is currently available. We previously showed that a genetically attenuated Yersinia pseudotuberculosis producing the Yersinia pestis F1 antigen was an efficient live oral vaccine against pneumonic plague. This candidate vaccine however failed to confer full protection against bubonic plague and did not produce F1 stably. Methodology/Principal Findings The caf operon encoding F1 was inserted into the chromosome of a genetically attenuated Y. pseudotuberculosis, yielding the VTnF1 strain, which stably produced the F1 capsule. Given orally to mice, VTnF1 persisted two weeks in the mouse gut and induced a high humoral response targeting both F1 and other Y. pestis antigens. The strong cellular response elicited was directed mostly against targets other than F1, but also against F1. It involved cells with a Th1—Th17 effector profile, producing IFNγ, IL-17, and IL-10. A single oral dose (108 CFU) of VTnF1 conferred 100% protection against pneumonic plague using a high-dose challenge (3,300 LD50) caused by the fully virulent Y. pestis CO92. Moreover, vaccination protected 100% of mice from bubonic plague caused by a challenge with 100 LD50 Y. pestis and 93% against a high-dose infection (10,000 LD50). Protection involved fast-acting mechanisms controlling Y. pestis spread out of the injection site, and the protection provided was long-lasting, with 93% and 50% of mice surviving bubonic and pneumonic plague respectively, six months after vaccination. Vaccinated mice also survived bubonic and pneumonic plague caused by a high-dose of non-encapsulated (F1-) Y. pestis. Significance VTnF1 is an easy-to-produce, genetically stable plague vaccine candidate, providing a highly efficient and long-lasting protection against both bubonic and pneumonic plague caused by wild type or un-encapsulated (F1-negative) Y. pestis. To our knowledge, VTnF1 is the only plague vaccine ever reported that could provide high and durable protection

Meta-analysis of variables affecting mouse protection efficacy of whole organism Brucella vaccines and vaccine candidates

PubMed Central

2013-01-01

Background Vaccine protection investigation includes three processes: vaccination, pathogen challenge, and vaccine protection efficacy assessment. Many variables can affect the results of vaccine protection. Brucella, a genus of facultative intracellular bacteria, is the etiologic agent of brucellosis in humans and multiple animal species. Extensive research has been conducted in developing effective live attenuated Brucella vaccines. We hypothesized that some variables play a more important role than others in determining vaccine protective efficacy. Using Brucella vaccines and vaccine candidates as study models, this hypothesis was tested by meta-analysis of Brucella vaccine studies reported in the literature. Results Nineteen variables related to vaccine-induced protection of mice against infection with virulent brucellae were selected based on modeling investigation of the vaccine protection processes. The variable "vaccine protection efficacy" was set as a dependent variable while the other eighteen were set as independent variables. Discrete or continuous values were collected from papers for each variable of each data set. In total, 401 experimental groups were manually annotated from 74 peer-reviewed publications containing mouse protection data for live attenuated Brucella vaccines or vaccine candidates. Our ANOVA analysis indicated that nine variables contributed significantly (P-value < 0.05) to Brucella vaccine protection efficacy: vaccine strain, vaccination host (mouse) strain, vaccination dose, vaccination route, challenge pathogen strain, challenge route, challenge-killing interval, colony forming units (CFUs) in mouse spleen, and CFU reduction compared to control group. The other 10 variables (e.g., mouse age, vaccination-challenge interval, and challenge dose) were not found to be statistically significant (P-value > 0.05). The protection level of RB51 was sacrificed when the values of several variables (e.g., vaccination route, vaccine viability

Protective Efficacy of the Conserved NP, PB1, and M1 Proteins as Immunogens in DNA- and Vaccinia Virus-Based Universal Influenza A Virus Vaccines in Mice.

PubMed

Wang, Wenling; Li, Renqing; Deng, Yao; Lu, Ning; Chen, Hong; Meng, Xin; Wang, Wen; Wang, Xiuping; Yan, Kexia; Qi, Xiangrong; Zhang, Xiangmin; Xin, Wei; Lu, Zhenhua; Li, Xueren; Bian, Tao; Gao, Yingying; Tan, Wenjie; Ruan, Li

2015-06-01

The conventional hemagglutinin (HA)- and neuraminidase (NA)-based influenza vaccines need to be updated most years and are ineffective if the glycoprotein HA of the vaccine strains is a mismatch with that of the epidemic strain. Universal vaccines targeting conserved viral components might provide cross-protection and thus complement and improve conventional vaccines. In this study, we generated DNA plasmids and recombinant vaccinia viruses expressing the conserved proteins nucleoprotein (NP), polymerase basic 1 (PB1), and matrix 1 (M1) from influenza virus strain A/Beijing/30/95 (H3N2). BALB/c mice were immunized intramuscularly with a single vaccine based on NP, PB1, or M1 alone or a combination vaccine based on all three antigens and were then challenged with lethal doses of the heterologous influenza virus strain A/PR/8/34 (H1N1). Vaccines based on NP, PB1, and M1 provided complete or partial protection against challenge with 1.7 50% lethal dose (LD50) of PR8 in mice. Of the three antigens, NP-based vaccines induced protection against 5 LD50 and 10 LD50 and thus exhibited the greatest protective effect. Universal influenza vaccines based on the combination of NP, PB1, and M1 induced a strong immune response and thus might be an alternative approach to addressing future influenza virus pandemics. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Protective Vaccine Efficacy of the Complete Form of PPE39 Protein from Mycobacterium tuberculosis Beijing/K Strain in Mice.

PubMed

Kim, Ahreum; Hur, Yun-Gyoung; Gu, Sunwha; Cho, Sang-Nae

2017-11-01

The aim of this study was to evaluate the protective efficacy of MTBK_24820, a complete form of PPE39 protein derived from a predominant Beijing/K strain of Mycobacterium tuberculosis in South Korea. Mice were immunized with MTKB_24820, M. bovis Bacilli Calmette-Guérin (BCG), or adjuvant prior to a high-dosed Beijing/K strain aerosol infection. After 4 and 9 weeks, bacterial loads were determined and histopathologic and immunologic features in the lungs and spleens of the M. tuberculosis -infected mice were analyzed. Putative immunogenic T-cell epitopes were examined using synthetic overlapping peptides. Successful immunization of MTBK_24820 in mice was confirmed by increased IgG responses ( P < 0.05) and recalled gamma interferon (IFN-γ), interleukin-2 (IL-2), IL-6, and IL-17 responses ( P < 0.05 or P < 0.01) to MTBK_24820. After challenge with the Beijing/K strain, an approximately 0.5 to 1.0 log 10 reduction in CFU in lungs and fewer lung inflammation lesions were observed in MTBK_24820-immunized mice compared to those for control mice. Moreover, MTBK_24820 immunization elicited significantly higher numbers of CD4 + T cells producing protective cytokines, such as IFN-γ and IL-17, in lungs and spleens ( P < 0.01) and CD4 + multifunctional T cells producing IFN-γ, tumor necrosis factor alpha (TNF-α), and/or IL-17 ( P < 0.01) than in control mice, suggesting protection comparable to that of BCG against the hypervirulent Beijing/K strain. The dominant immunogenic T-cell epitopes that induced IFN-γ production were at the N terminus (amino acids 85 to 102 and 217 to 234). Its vaccine potential, along with protective immune responses in vivo , may be informative for vaccine development, particularly in regions where the M. tuberculosis Beijing/K-strain is frequently isolated from TB patients. Copyright © 2017 American Society for Microbiology.

Protective Effect of Vaccine Promoted Neutralizing Antibodies against the Intracellular Pathogen Chlamydia trachomatis.

PubMed

Olsen, Anja Weinreich; Lorenzen, Emma Kathrine; Rosenkrands, Ida; Follmann, Frank; Andersen, Peter

2017-01-01

There is an unmet need for a vaccine to control Chlamydia trachomatis ( C.t .) infections. We have recently designed a multivalent heterologous immuno-repeat 1 (Hirep1) vaccine construct based on major outer membrane protein variable domain (VD) 4 regions from C.t . serovars (Svs) D-F. Hirep1 administered in the Cationic Adjuvant Formulation no. 1 (CAF01) promoted neutralizing antibodies in concert with CD4 + T cells and protected against genital infection. In the current study, we examined the protective role of the antibody (Ab) response in detail. Mice were vaccinated with either Hirep1 or a vaccine construct based on a homologous multivalent construct of extended VD4's from SvF (extVD4 F *4), adjuvanted in CAF01. Hirep1 and extVD4 F *4 induced similar levels of Ab and cell-mediated immune responses but differed in the fine specificity of the B cell epitopes targeted in the VD4 region. Hirep1 induced a strong response toward a neutralizing epitope (LNPTIAG) and the importance of this epitope for neutralization was demonstrated by competitive inhibition with the corresponding peptide. Immunization with extVD4 F *4 skewed the response to a non-neutralizing epitope slightly upstream in the sequence. Vaccination with Hirep1 as opposed to extVD4 F *4 induced significant protection against infection in mice both in short- and long-term vaccination experiments, signifying a key role for Hirep1 neutralizing antibodies during protection against C.t . Finally, we show that passive immunization of Rag1 knockout mice with Hirep1 antibodies completely prevented the establishment of infection in 48% of the mice, demonstrating an isolated role for neutralizing antibodies in controlling infection. Our data emphasize the role of antibodies in early protection against C.t . and support the inclusion of neutralizing targets in chlamydia vaccines.

Protective Effect of Vaccine Promoted Neutralizing Antibodies against the Intracellular Pathogen Chlamydia trachomatis

PubMed Central

Olsen, Anja Weinreich; Lorenzen, Emma Kathrine; Rosenkrands, Ida; Follmann, Frank; Andersen, Peter

2017-01-01

There is an unmet need for a vaccine to control Chlamydia trachomatis (C.t.) infections. We have recently designed a multivalent heterologous immuno-repeat 1 (Hirep1) vaccine construct based on major outer membrane protein variable domain (VD) 4 regions from C.t. serovars (Svs) D–F. Hirep1 administered in the Cationic Adjuvant Formulation no. 1 (CAF01) promoted neutralizing antibodies in concert with CD4+ T cells and protected against genital infection. In the current study, we examined the protective role of the antibody (Ab) response in detail. Mice were vaccinated with either Hirep1 or a vaccine construct based on a homologous multivalent construct of extended VD4’s from SvF (extVD4F*4), adjuvanted in CAF01. Hirep1 and extVD4F*4 induced similar levels of Ab and cell-mediated immune responses but differed in the fine specificity of the B cell epitopes targeted in the VD4 region. Hirep1 induced a strong response toward a neutralizing epitope (LNPTIAG) and the importance of this epitope for neutralization was demonstrated by competitive inhibition with the corresponding peptide. Immunization with extVD4F*4 skewed the response to a non-neutralizing epitope slightly upstream in the sequence. Vaccination with Hirep1 as opposed to extVD4F*4 induced significant protection against infection in mice both in short- and long-term vaccination experiments, signifying a key role for Hirep1 neutralizing antibodies during protection against C.t. Finally, we show that passive immunization of Rag1 knockout mice with Hirep1 antibodies completely prevented the establishment of infection in 48% of the mice, demonstrating an isolated role for neutralizing antibodies in controlling infection. Our data emphasize the role of antibodies in early protection against C.t. and support the inclusion of neutralizing targets in chlamydia vaccines. PMID:29312283

Evaluation of protective efficacy of three novel H3N2 canine influenza vaccines.

PubMed

Tu, Liqing; Zhou, Pei; Li, Lutao; Li, Xiuzhen; Hu, Renjun; Jia, Kun; Sun, Lingshuang; Yuan, Ziguo; Li, Shoujun

2017-11-17

Canine influenza virus (CIV) has the potential risk to spread in different areas and dog types. Thus, there is a growing need to develop an effective vaccine to control CIV disease. Here, we developed three vaccine candidates: 1) a recombinant pVAX1 vector expressing H3N2 CIV hemagglutinin (pVAX1-HA); 2) a live attenuated canine adenovirus type 2 expressing H3N2 CIV hemagglutinin (rCAV2-HA); and 3) an inactivated H3N2 CIV (A/canine/Guangdong/01/2006 (H3N2)). Mice received an initial intramuscular immunization that followed two booster injections at 2 and 4 weeks post-vaccination (wpv). The splenic lymphocytes were collected to assess the immune responses at 6 wpv. The protective efficacy was evaluated by challenging H3N2 CIV after vaccination (at 6 wpv). Our results demonstrated that all three vaccine candidates elicited cytokine and antibody responses in mice. The rCAV2-HA vaccine and the inactivated vaccine generated efficient protective efficacy in mice, whereas limited protection was provided by the pVAX1-HA DNA vaccine. Therefore, both the rCAV2-HA live recombinant virus and the inactivated CIV could be used as potential novel vaccines against H3N2CIV. This study provides guidance for choosing the most appropriate vaccine for the prevention and control of CIV disease.

Schistosoma mansoni: vaccination of mice with 10-krad-irradiated, cryopreserved schistosomules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lewis, F.A.; Stirewalt, M.A.; Leef, J.L.

1984-06-01

Protection against a Schistosoma mansoni cercarial challenge was evaluated in mice immunized with a vaccine composed of 10-krad-irradiated, cryopreserved schistosomules. The level of resistance induced in C57B1/6 or NMRI (CV) mice increased with the number of schistosomules injected. Up to 83% reduction in challenge worm burden was achieved when 5000 schistosomules were injected per mouse. Intramuscular injection of the vaccine was superior to subcutaneous. Multiple immunizations, up to 3 at 4-week intervals, did not increase the resistance induced by a single immunization. A high level of protection developed in as little as 2 weeks and was maintained through at leastmore » 12 weeks postimmunization. The vaccine irradiated with 10 krad from either a 60-cobalt or 137-cesium source induced equivalent levels of resistance, and no differences were found in the immunogenicity of vaccines comprised of organisms irradiated as cercariae or as 1- to 3-hr-old schistosomules. These findings are basic to the development of a cryopreserved, live vaccine against schistosomiasis of humans or domestic animals.« less

Pertussis Maternal Immunization: Narrowing the Knowledge Gaps on the Duration of Transferred Protective Immunity and on Vaccination Frequency

PubMed Central

Gaillard, María Emilia; Bottero, Daniela; Zurita, María Eugenia; Carriquiriborde, Francisco; Martin Aispuro, Pablo; Bartel, Erika; Sabater-Martínez, David; Bravo, María Sol; Castuma, Celina; Hozbor, Daniela Flavia

2017-01-01

Maternal safety through pertussis vaccination and subsequent maternal–fetal-antibody transfer are well documented, but information on infant protection from pertussis by such antibodies and by subsequent vaccinations is scarce. Since mice are used extensively for maternal-vaccination studies, we adopted that model to narrow those gaps in our understanding of maternal pertussis immunization. Accordingly, we vaccinated female mice with commercial acellular pertussis (aP) vaccine and measured offspring protection against Bordetella pertussis challenge and specific-antibody levels with or without revaccination. Maternal immunization protected the offspring against pertussis, with that immune protection transferred to the offspring lasting for several weeks, as evidenced by a reduction (4–5 logs, p < 0.001) in the colony-forming-units recovered from the lungs of 16-week-old offspring. Moreover, maternal-vaccination-acquired immunity from the first pregnancy still conferred protection to offspring up to the fourth pregnancy. Under the conditions of our experimental protocol, protection to offspring from the aP-induced immunity is transferred both transplacentally and through breastfeeding. Adoptive-transfer experiments demonstrated that transferred antibodies were more responsible for the protection detected in offspring than transferred whole spleen cells. In contrast to reported findings, the protection transferred was not lost after the vaccination of infant mice with the same or other vaccine preparations, and conversely, the immunity transferred from mothers did not interfere with the protection conferred by infant vaccination with the same or different vaccines. These results indicated that aP-vaccine immunization of pregnant female mice conferred protective immunity that is transferred both transplacentally and via offspring breastfeeding without compromising the protection boostered by subsequent infant vaccination. These results—though admittedly not

Nasal Vaccination Stimulates CD8+ T Cells for Potent Protection Against Mucosal Brucella melitensis Challenge

PubMed Central

Clapp, Beata; Yang, Xinghong; Thornburg, Theresa; Walters, Nancy; Pascual, David W.

2016-01-01

Brucellosis remains a significant zoonotic threat worldwide. Humans and animals acquire infection via their oropharynx and upper respiratory tract following oral or aerosol exposure. After mucosal infection, brucellosis develops into a systemic disease. Mucosal vaccination could offer a viable alternative to conventional injection practices to deter disease. Using a nasal vaccination approach, the ΔznuA B. melitensis was found to confer potent protection against pulmonary Brucella challenge, and reduce colonization of spleens and lungs by more than 2500-fold, with more than 50% of vaccinated mice showing no detectable brucellae. Furthermore, tenfold more brucellae-specific, IFN-γ-producing CD8+ T cells than CD4+ T cells were induced in the spleen and respiratory lymph nodes. Evaluation of pulmonary and splenic CD8+ T cells from mice vaccinated with ΔznuA B. melitensis revealed that these expressed an activated effector memory (CD44hiCD62LloCCR7lo) T cells producing elevated levels of IFN-γ, TNF-α, perforin, and granzyme B. To assess the relative importance of these increased numbers of CD8+ T cells, CD8−/− mice were challenged with virulent B. melitensis, and they showed markedly increased bacterial loads in organs in contrast to similarly challenged CD4−/− mice. Only ΔznuA B. melitensis- and Rev-1-vaccinated CD4−/− and wild-type mice, not CD8−/− mice, were completely protected against Brucella challenge. Determination of cytokines responsible for conferring protection showed the relative importance of IFN-γ, but not IL-17. Unlike wild-type mice, IL-17 was greatly induced in IFN-γ−/− mice, but IL-17 could not substitute for IFN-γ’s protection, although an increase in brucellae dissemination was observed upon in vivo IL-17 neutralization. These results show that nasal ΔznuA B. melitensis vaccination represents an attractive means to stimulate systemic and mucosal immune protection via CD8+ T cell engagement. PMID:26752510

Successive Intramuscular Boosting with IFN-Alpha Protects Mycobacterium bovis BCG-Vaccinated Mice against M. lepraemurium Infection

PubMed Central

Guerrero, G. G.; Rangel-Moreno, J.; Islas-Trujillo, S.; Rojas-Espinosa, Ó.

2015-01-01

Leprosy caused by Mycobacterium leprae primarily affects the skin and peripheral nerves. As a human infectious disease, it is still a significant health and economic burden on developing countries. Although multidrug therapy is reducing the number of active cases to approximately 0.5 million, the number of cases per year is not declining. Therefore, alternative host-directed strategies should be addressed to improve treatment efficacy and outcome. In this work, using murine leprosy as a model, a very similar granulomatous skin lesion to human leprosy, we have found that successive IFN-alpha boosting protects BCG-vaccinated mice against M. lepraemurium infection. No difference in the seric isotype and all IgG subclasses measured, neither in the TH1 nor in the TH2 type cytokine production, was seen. However, an enhanced iNOS/NO production in BCG-vaccinated/i.m. IFN-alpha boosted mice was observed. The data provided in this study suggest a promising use for IFN-alpha boosting as a new prophylactic alternative to be explored in human leprosy by targeting host innate cell response. PMID:26484351

Efficacy of a Parainfluenza Virus 5 (PIV5)-Based H7N9 Vaccine in Mice and Guinea Pigs: Antibody Titer towards HA Was Not a Good Indicator for Protection

PubMed Central

Johnson, Scott; Dlugolenski, Daniel; Phan, Shannon; Tompkins, S. Mark; He, Biao

2015-01-01

H7N9 has caused fatal infections in humans. A safe and effective vaccine is the best way to prevent large-scale outbreaks in the human population. Parainfluenza virus 5 (PIV5), an avirulent paramyxovirus, is a promising vaccine vector. In this work, we generated a recombinant PIV5 expressing the HA gene of H7N9 (PIV5-H7) and tested its efficacy against infection with influenza virus A/Anhui/1/2013 (H7N9) in mice and guinea pigs. PIV5-H7 protected the mice against lethal H7N9 challenge. Interestingly, the protection did not require antibody since PIV5-H7 protected JhD mice that do not produce antibody against lethal H7N9 challenge. Furthermore, transfer of anti-H7 serum did not protect mice against H7N9 challenge. PIV5-H7 generated high HAI titers in guinea pigs, however it did not protect against H7N9 infection or transmission. Intriguingly, immunization of guinea pigs with PIV5-H7 and PIV5 expressing NP of influenza A virus H5N1 (PIV5-NP) conferred protection against H7N9 infection and transmission. Thus, we have obtained a H7N9 vaccine that protected both mice and guinea pigs against lethal H7N9 challenge and infection respectively. PMID:25803697

Subunit Vaccine Preparation of Bovine Rotavirus and Its Efficacy in Mice.

PubMed

Suocheng, Wei; Tuanjie, Che; Changjun, Song; Fengling, Tian; Zhongren, Ma

2015-09-01

Rotaviruses (RV) are important viral diarrheal agents in calves. Vaccination is an optimum measure to prevent bovine rotaviruses (BRV) infection. However, little research on BRV VP7 vaccine has been done and currently there is no BRV vaccine. To prepare a subunit vaccine of BRV and investigate its efficacy. Total RNA was extracted from MA104 cells infected with bovine rotavirus (BRV) strain GSB01. BRV VP7 gene was amplified using real time fluorescence quantitative PCR (qPCR). The pEASY-T3-VP7 plasmid was digested using HindⅢ and BamHI restriction endonucleases, then recombined into the prokaryotic expression vector pET32a. The pET32a-VP7 and pET32a-VP7-LTB (heat-labile enterotoxin B subunit) were transformed into BL21 (DE3) competent cells of Escherichia coli, respectively, and induced with IPTG, then analyzed using SDS-PAGE. Sixty mice were randomly divided into three groups (n=20). Group A mice was used as His-tag control and mice in group B and C were inoculated with pET32a-VP7 and pET32a-VP7-LTB, respectively. VP7 IgG antibody titers and protection efficiency of pET32a-VP7-LTB were further determined in neonatal mice challenged with GSB01 BRV strain. SDS-PAGE analysis showed that the pET32a-VP7 was highly expressed in the BL21 (DE3) cells. PET32a-VP7 and pET32a-VP7-LTB protein could promote VP7 IgG antibody titer（8.33×103 vs. 17.26×103）in mice. Immunization protection ratios of pET32a-VP7 and pET32a-VP7-LTB proteins in the neonatal mice were 86.4% and 91.7%, respectively. The fusion protein of pET32a-VP7-LTB had excellent immunogenicity and protected mice from BRV infection. Our findings can be used for further developing of a high-efficiency subunit vaccine of BRV.

Molecular Smallpox Vaccine Delivered by Alphavirus Replicons Elicits Protective Immunity in Mice and Non-human Primates

PubMed Central

Hooper, Jay W.; Ferro, Anthony M.; Golden, Joseph W.; Silvera, Peter; Dudek, Jeanne; Alterson, Kim; Custer, Max; Rivers, Bryan; Morris, John; Owens, Gary; Smith, Jonathan F.; Kamrud, Kurt I.

2009-01-01

Naturally occurring smallpox was eradicated as a result of successful vaccination campaigns during the 1960s and 70s. Because of its highly contagious nature and high mortality rate, smallpox has significant potential as a biological weapon. Unfortunately, the current vaccine for orthopoxviruses is contraindicated for large portions of the population. Thus, there is a need for new, safe, and effective orthopoxvirus vaccines. Alphavirus replicon vectors, derived from strains of Venezuelan equine encephalitis virus, are being used to develop alternatives to the current smallpox vaccine. Here, we demonstrated that virus-like replicon particles (VRP) expressing the vaccinia virus A33R, B5R, A27L, and L1R genes elicited protective immunity in mice comparable to vaccination with live-vaccinia virus. Furthermore, cynomolgus macaques vaccinated with a combination of the four poxvirus VRPs (4pox-VRP) developed antibody responses to each antigen. These antibody responses were able to neutralize and inhibit the spread of both vaccinia virus and monkeypox virus. Macaques vaccinated with 4pox-VRP, flu HA VRP (negative control), or live-vaccinia virus (positive control) were challenged intravenously with 5 × 106 PFU of monkeypox virus 1 month after the second VRP vaccination. Four of the six negative control animals succumbed to monkeypox and the remaining two animals demonstrated either severe or grave disease. Importantly, all 10 macaques vaccinated with the 4pox-VRP vaccine survived without developing severe disease. These findings revealed that a single-boost VRP smallpox vaccine shows promise as a safe alternative to the currently licensed live-vaccinia virus smallpox vaccine. PMID:19833247

A Multistage Subunit Vaccine Effectively Protects Mice Against Primary Progressive Tuberculosis, Latency and Reactivation.

PubMed

Ma, Jilei; Teng, Xindong; Wang, Xiaochun; Fan, Xionglin; Wu, Yaqi; Tian, Maopeng; Zhou, Zijie; Li, Longmeng

2017-08-01

Adult tuberculosis (TB) is the main cause of TB epidemic and death. The infection results mainly by endogenous reactivation of latent TB infection and secondarily transmitted by exogenous infection. There is no vaccine for adult TB. To this end, we first chose antigens from a potential antigenic reservoir. The antigens strongly recognized T cells from latent and active TB infections that responded to antigens expressed by Mycobacterium tuberculosis cultured under different metabolic states. Fusions of single-stage polyprotein CTT3H, two-stage polyprotein A1D4, and multistage CMFO were constructed. C57BL/6 mice vaccinated with DMT adjuvant ed CMFO (CMFO-DMT) were protected more significantly than by CTT3H-DMT, and efficacy was similar to that of the only licensed vaccine, Bacillus Calmette-Guérin (BCG) and A1D4-DMT in the M. tuberculosis primary infection model. In the setting of BCG priming and latent TB infection, M. tuberculosis in the lung and spleen was eliminated more effectively in mice boosted with CMFO-DMT rather than with BCG, A1D4-DMT, or CTT3H-DMT. In particular, sterile immunity was only conferred by CMFO-DMT, which was associated with expedited homing of interferon-gamma + CD4 + T EM and interleukin-2 + T CM cells from the spleen to the infected lung. CMFO-DMT represents a promising candidate to prevent the occurrence of adult TB through both prophylactic and therapeutic methods, and warrants assessment in preclinical and clinical trials. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Nonreplicating Influenza A Virus Vaccines Confer Broad Protection against Lethal Challenge

PubMed Central

Baz, Mariana; Boonnak, Kobporn; Paskel, Myeisha; Santos, Celia; Powell, Timothy; Townsend, Alain

2015-01-01

ABSTRACT New vaccine technologies are being investigated for their ability to elicit broadly cross-protective immunity against a range of influenza viruses. We compared the efficacies of two intranasally delivered nonreplicating influenza virus vaccines (H1 and H5 S-FLU) that are based on the suppression of the hemagglutinin signal sequence, with the corresponding H1N1 and H5N1 cold-adapted (ca) live attenuated influenza virus vaccines in mice and ferrets. Administration of two doses of H1 or H5 S-FLU vaccines protected mice and ferrets from lethal challenge with homologous, heterologous, and heterosubtypic influenza viruses, and two doses of S-FLU and ca vaccines yielded comparable effects. Importantly, when ferrets immunized with one dose of H1 S-FLU or ca vaccine were challenged with the homologous H1N1 virus, the challenge virus failed to transmit to naive ferrets by the airborne route. S-FLU technology can be rapidly applied to any emerging influenza virus, and the promising preclinical data support further evaluation in humans. PMID:26489862

Killed but metabolically active Bacillus anthracis vaccines induce broad and protective immunity against anthrax.

PubMed

Skoble, Justin; Beaber, John W; Gao, Yi; Lovchik, Julie A; Sower, Laurie E; Liu, Weiqun; Luckett, William; Peterson, Johnny W; Calendar, Richard; Portnoy, Daniel A; Lyons, C Rick; Dubensky, Thomas W

2009-04-01

Bacillus anthracis is the causative agent of anthrax. We have developed a novel whole-bacterial-cell anthrax vaccine utilizing B. anthracis that is killed but metabolically active (KBMA). Vaccine strains that are asporogenic and nucleotide excision repair deficient were engineered by deleting the spoIIE and uvrAB genes, rendering B. anthracis extremely sensitive to photochemical inactivation with S-59 psoralen and UV light. We also introduced point mutations into the lef and cya genes, which allowed inactive but immunogenic toxins to be produced. Photochemically inactivated vaccine strains maintained a high degree of metabolic activity and secreted protective antigen (PA), lethal factor, and edema factor. KBMA B. anthracis vaccines were avirulent in mice and induced less injection site inflammation than recombinant PA adsorbed to aluminum hydroxide gel. KBMA B. anthracis-vaccinated animals produced antibodies against numerous anthrax antigens, including high levels of anti-PA and toxin-neutralizing antibodies. Vaccination with KBMA B. anthracis fully protected mice against challenge with lethal doses of toxinogenic unencapsulated Sterne 7702 spores and rabbits against challenge with lethal pneumonic doses of fully virulent Ames strain spores. Guinea pigs vaccinated with KBMA B. anthracis were partially protected against lethal Ames spore challenge, which was comparable to vaccination with the licensed vaccine anthrax vaccine adsorbed. These data demonstrate that KBMA anthrax vaccines are well tolerated and elicit potent protective immune responses. The use of KBMA vaccines may be broadly applicable to bacterial pathogens, especially those for which the correlates of protective immunity are unknown.

A single vaccination with non-replicating MVA at birth induces both immediate and long-term protective immune responses.

PubMed

Cheminay, Cédric; Körner, Jana; Bernig, Constanze; Brückel, Michael; Feigl, Markus; Schletz, Martin; Suter, Mark; Chaplin, Paul; Volkmann, Ariane

2018-04-25

Newborns are considered difficult to protect against infections shortly after birth, due to their ineffective immune system that shows quantitative and qualitative differences compared to adults. However, here we show that a single vaccination of mice at birth with a replication-deficient live vaccine Modified Vaccinia Ankara [MVA] efficiently induces antigen-specific B- and T-cells that fully protect against a lethal Ectromelia virus challenge. Protection was induced within 2 weeks and using genetically modified mice we show that this protection was mainly T-cell dependent. Persisting immunological T-cell memory and neutralizing antibodies were obtained with the single vaccination. Thus, MVA administered as early as at birth induced immediate and long-term protection against an otherwise fatal disease and appears attractive as a new generation smallpox vaccine that is effective also in children. Moreover, it may have the potential to serve as platform for childhood vaccines as indicated by measles specific T- and B-cell responses induced in newborn mice vaccinated with recombinant MVA expressing measles antigens. Copyright © 2018 Elsevier Ltd. All rights reserved.

Immunogenicity and Protection Efficacy of Subunit-based Smallpox Vaccines Using Variola Major Antigens

PubMed Central

Sakhatskyy, Pavlo; Wang, Shixia; Zhang, Chuanyou; Chou, Te-Hui; Kishko, Michael; Lu, Shan

2008-01-01

The viral strain responsible for smallpox infection is variola major (VARV). As a result of the successful eradication of smallpox with the vaccinia virus (VACV), the general population is no longer required to receive a smallpox vaccine, and will have no protection against smallpox. This lack of immunity is a concern due to the potential for use of smallpox as a biological weapon. Considerable progress has been made in the development of subunit-based smallpox vaccines resulting from the identification of VACV protective antigens. It also offers the possibility of using antigens from VARV to formulate the next generation subunit-based smallpox vaccines. Here, we show that codon-optimized DNA vaccines expressing three VARV antigens (A30, B7 and F8) and their recombinant protein counterparts elicited high-titer, cross-reactive, VACV neutralizing antibody responses in mice. Vaccinated mice were protected from intraperitoneal and intranasal challenges with VACV. These results suggest the feasibility of a subunit smallpox vaccine based on the VARV antigen sequences to induce immunity against poxvirus infection. PMID:17950773

Immunogenicity and protection efficacy of subunit-based smallpox vaccines using variola major antigens.

PubMed

Sakhatskyy, Pavlo; Wang, Shixia; Zhang, Chuanyou; Chou, Te-Hui; Kishko, Michael; Lu, Shan

2008-02-05

The viral strain responsible for smallpox infection is variola major (VARV). As a result of the successful eradication of smallpox with the vaccinia virus (VACV), the general population is no longer required to receive a smallpox vaccine, and will have no protection against smallpox. This lack of immunity is a concern due to the potential for use of smallpox as a biological weapon. Considerable progress has been made in the development of subunit-based smallpox vaccines resulting from the identification of VACV protective antigens. It also offers the possibility of using antigens from VARV to formulate the next generation subunit-based smallpox vaccines. Here, we show that codon-optimized DNA vaccines expressing three VARV antigens (A30, B7 and F8) and their recombinant protein counterparts elicited high-titer, cross-reactive, VACV neutralizing antibody responses in mice. Vaccinated mice were protected from intraperitoneal and intranasal challenges with VACV. These results suggest the feasibility of a subunit smallpox vaccine based on VARV antigen sequences to induce immunity against poxvirus infection.

Evaluation of protective efficacy of three novel H3N2 canine influenza vaccines

PubMed Central

Li, Lutao; Li, Xiuzhen; Hu, Renjun; Jia, Kun; Sun, Lingshuang; Yuan, Ziguo; Li, Shoujun

2017-01-01

Canine influenza virus (CIV) has the potential risk to spread in different areas and dog types. Thus, there is a growing need to develop an effective vaccine to control CIV disease. Here, we developed three vaccine candidates: 1) a recombinant pVAX1 vector expressing H3N2 CIV hemagglutinin (pVAX1-HA); 2) a live attenuated canine adenovirus type 2 expressing H3N2 CIV hemagglutinin (rCAV2-HA); and 3) an inactivated H3N2 CIV (A/canine/Guangdong/01/2006 (H3N2)). Mice received an initial intramuscular immunization that followed two booster injections at 2 and 4 weeks post-vaccination (wpv). The splenic lymphocytes were collected to assess the immune responses at 6 wpv. The protective efficacy was evaluated by challenging H3N2 CIV after vaccination (at 6 wpv). Our results demonstrated that all three vaccine candidates elicited cytokine and antibody responses in mice. The rCAV2-HA vaccine and the inactivated vaccine generated efficient protective efficacy in mice, whereas limited protection was provided by the pVAX1-HA DNA vaccine. Therefore, both the rCAV2-HA live recombinant virus and the inactivated CIV could be used as potential novel vaccines against H3N2CIV. This study provides guidance for choosing the most appropriate vaccine for the prevention and control of CIV disease. PMID:29228675

Vaccination with human amniotic epithelial cells confer effective protection in a murine model of Colon adenocarcinoma.

PubMed

Tabatabaei, M; Mosaffa, N; Ghods, R; Nikoo, S; Kazemnejad, S; Khanmohammadi, M; Mirzadeghan, E; Mahmoudi, A R; Bolouri, M R; Falak, R; Keshavarzi, B; Ramezani, M; Zarnani, A H

2018-04-01

As a prophylactic cancer vaccine, human amniotic membrane epithelial cells (hAECs) conferred effective protection in a murine model of colon cancer. The immunized mice mounted strong cross-protective CTL and antibody responses. Tumor burden was significantly reduced in tumor-bearing mice after immunization with hAECs. Placental cancer immunotherapy could be a promising approach for primary prevention of cancer. In spite of being the star of therapeutic strategies for cancer treatment, the results of immunotherapeutic approaches are still far from expectations. In this regard, primary prevention of cancer using prophylactic cancer vaccines has gained considerable attention. The immunologic similarities between cancer development and placentation have helped researchers to unravel molecular mechanisms responsible for carcinogenesis and to take advantage of stem cells from reproductive organs to elicit robust anti-cancer immune responses. Here, we showed that vaccination of mice with human amniotic membrane epithelial cells (hAECs) conferred effective protection against colon cancer and led to expansion of systemic and splenic cytotoxic T cell population and induction of cross-protective cytotoxic responses against tumor cells. Vaccinated mice mounted tumor-specific Th1 responses and produced cross-reactive antibodies against cell surface markers of cancer cells. Tumor burden was also significantly reduced in tumor-bearing mice immunized with hAECs. Our findings pave the way for potential future application of hAECs as an effective prophylactic cancer vaccine. © 2017 UICC.

Aerogenic vaccination with a Burkholderia mallei auxotroph protects against aerosol-initiated glanders in mice.

PubMed

Ulrich, Ricky L; Amemiya, Kei; Waag, David M; Roy, Chad J; DeShazer, David

2005-03-14

Burkholderia mallei is an obligate mammalian pathogen that causes the zoonotic disease glanders. Two live attenuated B. mallei strains, a capsule mutant and a branched-chain amino acid auxotroph, were evaluated for use as vaccines against aerosol-initiated glanders in mice. Animals were aerogenically vaccinated and serum samples were obtained before aerosol challenge with a high-dose (>300 times the LD50) of B. mallei ATCC 23344. Mice vaccinated with the capsule mutant developed a Th2-like Ig subclass antibody response and none survived beyond 5 days. In comparison, the auxotrophic mutant elicited a Th1-like Ig subclass antibody response and 25% of the animals survived for 1 month postchallenge. After a low-dose (5 times the LD50) aerosol challenge, the survival rates of auxotroph-vaccinated and unvaccinated animals were 50 and 0%, respectively. Thus, live attenuated strains that promote a Th1-like Ig response may serve as promising vaccine candidates against aerosol infection with B. mallei.

Loss of long term protection with the inclusion of HIV pol to a DNA vaccine encoding gag.

PubMed

Garrod, Tamsin J; Gargett, Tessa; Yu, Wenbo; Major, Lee; Burrell, Christopher J; Wesselingh, Steven; Suhrbier, Andreas; Grubor-Bauk, Branka; Gowans, Eric J

2014-11-04

Traditional vaccine strategies that induce antibody responses have failed to protect against HIV infection in clinical trials, and thus cell-mediated immunity is now an additional criterion. Recent clinical trials that aimed to induce strong T cell responses failed to do so. Therefore, to enhance induction of protective T cell responses, it is crucial that the optimum antigen combination is chosen. Limited research has been performed into the number of antigens selected for an HIV vaccine. This study aimed to compare DNA vaccines encoding either a single HIV antigen or a combination of two antigens, using intradermal vaccination of C57BL/6 mice. Immune assays were performed on splenocytes, and in vivo protection was examined by challenge with a chimeric virus, EcoHIV, able to infect mouse but not human leukocytes, at 10 days (short term) and 60 days (long term) post final vaccination. At 60 days there was significantly lower frequency of induced antigen-specific CD8(+) T cells in the spleens of pCMVgag-pol-vaccinated mice compared with mice which received pCMVgag only. Most importantly, short term viral control of EcoHIV was similar for pCMVgag and pCMVgag-pol-vaccinated mice at day 10, but only the pCMVgag-vaccinated significantly controlled EcoHIV at day 60 compared with pCMV-vaccinated mice, showing that control was reduced with the inclusion of the HIV pol gene. Copyright © 2014 Elsevier B.V. All rights reserved.

An Influenza HA and M2e Based Vaccine Delivered by a Novel Attenuated Salmonella Mutant Protects Mice against Homologous H1N1 Infection.

PubMed

Hajam, Irshad A; Lee, John H

2017-01-01

Attenuated Salmonella strains constitute a promising technology for the development of a more efficient multivalent protein based vaccines. In this study, we constructed a novel attenuated strain of Salmonella for the delivery and expression of the H1N1 hemagglutinin (HA) and the conserved extracellular domain of the matrix protein 2 (M2e). We demonstrated that the constructed Salmonella strain exhibited efficient HA and M2e protein expressions and little cytotoxicity and pathogenicity in mice. Using BALB/c mice as the model, we showed that the mice vaccinated with a Salmonella strain expressing HA and M2e protein antigens, respectively, induced significant production of HA and M2e-specific serum IgG1 and IgG2a responses, and of anti-HA interferon-γ producing T cells. Furthermore, immunization with Salmonella-HA-M2e-based vaccine via different routes provided protection in 66.66% orally, 100% intramuscularly, and 100% intraperitoneally immunized mice against the homologous H1N1 virus while none of the animals survived treated with either the PBS or the Salmonella carrying empty expression vector. Ex vivo stimulated dendritic cells (DCs) with heat killed Salmonella expressing HA demonstrated that DCs play an important role in the elicitation of HA-specific humoral immune responses in mice. In summary, Salmonella -HA-M2e-based vaccine elicits efficient antigen-specific humoral and cellular immune responses, and provides significant immune protection against a highly pathogenic H1N1 influenza virus.

Active vaccination with vaccinia virus A33 protects mice against lethal vaccinia and ectromelia viruses but not against cowpoxvirus; elucidation of the specific adaptive immune response.

PubMed

Paran, Nir; Lustig, Shlomo; Zvi, Anat; Erez, Noam; Israely, Tomer; Melamed, Sharon; Politi, Boaz; Ben-Nathan, David; Schneider, Paula; Lachmi, Batel; Israeli, Ofir; Stein, Dana; Levin, Reuven; Olshevsky, Udy

2013-07-10

Vaccinia virus protein A33 (A33VACV) plays an important role in protection against orthopoxviruses, and hence is included in experimental multi-subunit smallpox vaccines. In this study we show that single-dose vaccination with recombinant Sindbis virus expressing A33VACV, is sufficient to protect mice against lethal challenge with vaccinia virus WR (VACV-WR) and ectromelia virus (ECTV) but not against cowpox virus (CPXV), a closely related orthopoxvirus. Moreover, a subunit vaccine based on the cowpox virus A33 ortholog (A33CPXV) failed to protect against cowpox and only partially protected mice against VACV-WR challenge. We mapped regions of sequence variation between A33VACV and A33CPXVand analyzed the role of such variations in protection. We identified a single protective region located between residues 104-120 that harbors a putative H-2Kd T cell epitope as well as a B cell epitope - a target for the neutralizing antibody MAb-1G10 that blocks spreading of extracellular virions. Both epitopes in A33CPXV are mutated and predicted to be non-functional. Whereas vaccination with A33VACV did not induce in-vivo CTL activity to the predicted epitope, inhibition of virus spread in-vitro, and protection from lethal VACV challenge pointed to the B cell epitope highlighting the critical role of residue L118 and of adjacent compensatory residues in protection. This epitope's critical role in protection, as well as its modifications within the orthopoxvirus genus should be taken in context with the failure of A33 to protect against CPXV as demonstrated here. These findings should be considered when developing new subunit vaccines and monoclonal antibody based therapeutics against orthopoxviruses, especially variola virus, the etiologic agent of smallpox.

Active vaccination with vaccinia virus A33 protects mice against lethal vaccinia and ectromelia viruses but not against cowpoxvirus; elucidation of the specific adaptive immune response

PubMed Central

2013-01-01

Vaccinia virus protein A33 (A33VACV) plays an important role in protection against orthopoxviruses, and hence is included in experimental multi-subunit smallpox vaccines. In this study we show that single-dose vaccination with recombinant Sindbis virus expressing A33VACV, is sufficient to protect mice against lethal challenge with vaccinia virus WR (VACV-WR) and ectromelia virus (ECTV) but not against cowpox virus (CPXV), a closely related orthopoxvirus. Moreover, a subunit vaccine based on the cowpox virus A33 ortholog (A33CPXV) failed to protect against cowpox and only partially protected mice against VACV-WR challenge. We mapped regions of sequence variation between A33VACV and A33CPXVand analyzed the role of such variations in protection. We identified a single protective region located between residues 104–120 that harbors a putative H-2Kd T cell epitope as well as a B cell epitope - a target for the neutralizing antibody MAb-1G10 that blocks spreading of extracellular virions. Both epitopes in A33CPXV are mutated and predicted to be non-functional. Whereas vaccination with A33VACV did not induce in-vivo CTL activity to the predicted epitope, inhibition of virus spread in-vitro, and protection from lethal VACV challenge pointed to the B cell epitope highlighting the critical role of residue L118 and of adjacent compensatory residues in protection. This epitope’s critical role in protection, as well as its modifications within the orthopoxvirus genus should be taken in context with the failure of A33 to protect against CPXV as demonstrated here. These findings should be considered when developing new subunit vaccines and monoclonal antibody based therapeutics against orthopoxviruses, especially variola virus, the etiologic agent of smallpox. PMID:23842430

Immunization with a DNA vaccine encoding Toxoplasma gondii Superoxide dismutase (TgSOD) induces partial immune protection against acute toxoplasmosis in BALB/c mice.

PubMed

Liu, Yuan; Cao, Aiping; Li, Yawen; Li, Xun; Cong, Hua; He, Shenyi; Zhou, Huaiyu

2017-06-07

Toxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite that infects all warm-blooded animals including humans and causes toxoplasmosis. An effective vaccine could be an ideal choice for preventing and controlling toxoplasmosis. T. gondii Superoxide dismutase (TgSOD) might participate in affecting the intracellular growth of both bradyzoite and tachyzoite forms. In the present study, the TgSOD gene was used to construct a DNA vaccine (pEGFP-SOD). TgSOD gene was amplified and inserted into eukaryotic vector pEGFP-C1 and formed the DNA vaccine pEGFP-SOD. Then the BALB/c mice were immunized intramuscularly with the DNA vaccine and those injected with pEGFP-C1, PBS or nothing were treated as controls. Four weeks after the last immunization, all mouse groups followed by challenging intraperitoneally with tachyzoites of T. gondii ME49 strain. Results showed higher levels of total IgG, IgG2α in the sera and interferon gamma (IFN-γ) in the splenocytes from pEGFP-SOD inoculated mice than those unvaccinated, or inoculated with either empty plasmid vector or PBS. The proportions of CD4 + T cells and CD8 + T cells in the spleen from pEGFP-SOD inoculated mice were significantly (p < 0.05) increased compared to control groups. In addition, the survival time of mice immunized with pEGFP-SOD was significantly prolonged as compared to the controls (p < 0.05) although all the mice died. The present study revealed that the DNA vaccine triggered strong humoral and cellular immune responses, and aroused partial protective immunity against acute T. gondii infection in BALB/c mice. The collective data suggests the SOD may be a potential vaccine candidate for further development.

Oral Modeling of an Adenovirus-Based Quadrivalent Influenza Vaccine in Ferrets and Mice.

PubMed

Scallan, Ciaran D; Lindbloom, Jonathan D; Tucker, Sean N

2016-06-01

Oral vaccines delivered as tablets offer a number of advantages over traditional parenteral-based vaccines including the ease of delivery, lack of needles, no need for trained medical personnel, and the ability to formulate into temperature-stable tablets. We have been evaluating an oral vaccine platform based on recombinant adenoviral vectors for the purpose of creating a prophylactic vaccine to prevent influenza, and have demonstrated vaccine efficacy in animal models and substantial immunogenicity in humans. These studies have evaluated monovalent vaccines to date. To protect against the major circulating A and B influenza strains, a multivalent influenza vaccine will be required. In this study, the immunogenicity of orally delivered monovalent, bivalent, trivalent, and quadrivalent vaccines was tested in ferrets and mice. The various vaccine combinations were tested by blending monovalent recombinant adenovirus vaccines, each expressing hemagglutinin from a single strain. Human tablet delivery was modeled in animals by oral gavage in mice and by endoscopic delivery in ferrets. We demonstrated minimal interference between the various vaccine vectors when used in combination and that the oral quadrivalent vaccine compared favorably to an approved trivalent inactivated vaccine. The quadrivalent vaccine presented here produced immune responses that we predict should be capable of providing protection against multiple influenza strains, and the platform should have applications to other multivalent vaccines. Vaxart, Inc.

Cross-protection against Salmonella enteritidis infection in mice. III. Delayed hypersensitivity reaction and clearance of the challenge organism.

PubMed

Padmanaban, V D; Mittal, K R

1979-01-01

Mice were immunized with live vaccines and with live vaccines with complete adjuvant incorporating Salmonella enteritidis, Salmonella typhi-murium, Salmonella gallinarum or Salmonella pullorum. On the 21st day after vacination, the hypersensitivity reactions elicited by the mice to extracts of the challenge organism (S. enteritidis 5694 SMR) were assessed. The degree of delayed hypersensitivity reaction was compared with the level of protection induced by the vaccine. The role in protection of delayed hypersensitivity is discussed. Clearance of the challenge organism from the liver of previously vaccinated and unvaccinated mice was assessed quantitatively.

A hydrogen peroxide-inactivated virus vaccine elicits humoral and cellular immunity and protects against lethal West Nile virus infection in aged mice.

PubMed

Pinto, Amelia K; Richner, Justin M; Poore, Elizabeth A; Patil, Pradnya P; Amanna, Ian J; Slifka, Mark K; Diamond, Michael S

2013-02-01

West Nile virus (WNV) is an emerging pathogen that is now the leading cause of mosquito-borne and epidemic encephalitis in the United States. In humans, a small percentage of infected individuals develop severe neuroinvasive disease, with the greatest relative risk being in the elderly and immunocompromised, two populations that are difficult to immunize effectively with vaccines. While inactivated and subunit-based veterinary vaccines against WNV exist, currently there is no vaccine or therapy available to prevent or treat human disease. Here, we describe the generation and preclinical efficacy of a hydrogen peroxide (H(2)O(2))-inactivated WNV Kunjin strain (WNV-KUNV) vaccine as a candidate for further development. Both young and aged mice vaccinated with H(2)O(2)-inactivated WNV-KUNV produced robust adaptive B and T cell immune responses and were protected against stringent and lethal intracranial challenge with a heterologous virulent North American WNV strain. Our studies suggest that the H(2)O(2)-inactivated WNV-KUNV vaccine is safe and immunogenic and may be suitable for protection against WNV infection in vulnerable populations.

High Antigen Dose Is Detrimental to Post-Exposure Vaccine Protection against Tuberculosis.

PubMed

Billeskov, Rolf; Lindenstrøm, Thomas; Woodworth, Joshua; Vilaplana, Cristina; Cardona, Pere-Joan; Cassidy, Joseph P; Mortensen, Rasmus; Agger, Else Marie; Andersen, Peter

2017-01-01

Mycobacterium tuberculosis (Mtb), the etiologic agent of tuberculosis (TB), causes 1.8M deaths annually. The current vaccine, BCG, has failed to eradicate TB leaving 25% of the world's population with latent Mtb infection (LTBI), and 5-10% of these people will reactivate and develop active TB. An efficient therapeutic vaccine targeting LTBI could have an enormous impact on global TB incidence, and could be an important aid in fighting multidrug resistance, which is increasing globally. Here we show in a mouse model using the H56 (Ag85B-ESAT-6-Rv2660) TB vaccine candidate that post-exposure, but not preventive, vaccine protection requires low vaccine antigen doses for optimal protection. Loss of protection from high dose post-exposure vaccination was not associated with a loss of overall vaccine response magnitude, but rather with greater differentiation and lower functional avidity of vaccine-specific CD4 T cells. High vaccine antigen dose also led to a decreased ability of vaccine-specific CD4 T cells to home into the Mtb-infected lung parenchyma, a recently discovered important feature of T cell protection in mice. These results underscore the importance of T cell quality rather than magnitude in TB-vaccine protection, and the significant role that antigen dosing plays in vaccine-mediated protection.

Hybrid phage displaying SLAQVKYTSASSI induces protection against Candida albicans challenge in BALB/c mice.

PubMed

Wang, Yicun; Su, Quanping; Dong, Shuai; Shi, Hongxi; Gao, Xiang; Wang, Li

2014-01-01

The polymorphic fungus Candida albicans (C. albicans) can live as an aggressive pathogen and cause many diseases in hosts, for which no effective vaccine exists. The secreted aspartyl proteinase 2 (Sap2) plays a protective role in systemically infected BALB/c mice. Protective cellular immune responses can be preferentially induced when antigens are displayed on small particles. Therefore, the emphasis is placed on developing new phage vaccine to inhibit C. albicans infection. In this study, the ability of the hybrid phage displaying the epitope SLAQVKYTSASSI and recombinant protein of Sap2 (rSap2) for inducing immune protective responses against C. albicans infection was evaluated by lymphoproliferative assay, to gather cytokine and antibody measurements in BALB/c mice. Our results showed that, strong cellular and humoral immune responses were induced in a mouse model immunized with hybrid phage or rSap2. Furthermore, the protection against lethal challenge with C. albicans was observed in mice vaccinated hybrid phage without adjuvant. These findings demonstrate that the hybrid phage displaying the epitope SLAQVKYTSASSI might be a potential vaccine against C. albicans infections.

Vaccination with a DNA vaccine encoding Toxoplasma gondii ROP54 induces protective immunity against toxoplasmosis in mice.

PubMed

Yang, Wen-Bin; Zhou, Dong-Hui; Zou, Yang; Chen, Kai; Liu, Qing; Wang, Jin-Lei; Zhu, Xing-Quan; Zhao, Guang-Hui

2017-12-01

Toxoplasma gondii is an obligatory intracellular protozoan, which infects most of the warm-blooded animals, causing serious public health problems and enormous economic losses worldwide. The rhoptry effector protein 54 (ROP54) has been indicated as a virulence factor that promotes Toxoplasma infection by modulating GBP2 loading onto parasite-containing vacuoles, which can modulate some aspects of the host immune response. In order to evaluate the immuno-protective value of ROP54, we constructed a eukaryotic recombinant plasmid expressing T. gondii ROP54 and intramuscularly immunized Kunming mice with this recombinant plasmid against acute and chronic toxoplasmosis. All mice immunized with pVAX-ROP54 elicited a high level of specific antibody responses, a significant increase of lymphocyte proliferation, and a significant level of Th1-type cytokines (IFN-γ, IL-2 and IL-12p70), in addition to an increased production of Th2-type cytokines (IL-4 and IL-10). These results demonstrated that pVAX-ROP54 induced significant cellular and humoral (Th1/Th2) immune responses, which extended the survival time (13.0±1.15days for pVAX-ROP54 vs 6.7±0.48days for pVAX I, 6.8±0.42days for PBS and 6.5±0.53 for blank control) and significantly reduced cyst burden (35.9% for pVAX-ROP54, 1% for pVAX I and 2% for PBS, compared with blank control) of immunized mice. These results indicate that the recombinant ROP54 plasmid can provide partial protection and might be a potential vaccine candidate against acute and chronic toxoplasmosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Partial pathogen protection by tick-bite sensitization and epitope recognition in peptide-immunized HLA DR3 transgenic mice.

PubMed

Shattuck, Wendy M C; Dyer, Megan C; Desrosiers, Joe; Fast, Loren D; Terry, Frances E; Martin, William D; Moise, Leonard; De Groot, Anne S; Mather, Thomas N

2014-01-01

Ticks are notorious vectors of disease for humans, and many species of ticks transmit multiple pathogens, sometimes in the same tick bite. Accordingly, a broad-spectrum vaccine that targets vector ticks and pathogen transmission at the tick/host interface, rather than multiple vaccines against every possible tickborne pathogen, could become an important tool for resolving an emerging public health crisis. The concept for such a tick protective vaccine comes from observations of an acquired tick resistance (ATR) that can develop in non-natural hosts of ticks following sensitization to tick salivary components. Mice are commonly used as models to study immune responses to human pathogens but normal mice are natural hosts for many species of ticks and fail to develop ATR. We evaluated HLA DR3 transgenic (tg) "humanized" mice as a potential model of ATR and assessed the possibility of using this animal model for tick protective vaccine discovery studies. Serial tick infestations with pathogen-free Ixodes scapularis ticks were used to tick-bite sensitize HLA DR3 tg mice. Sensitization resulted in a cytokine skew favoring a Th2 bias as well as partial (57%) protection to infection with Lyme disease spirochetes (Borrelia burgdorferi) following infected tick challenge when compared to tick naïve counterparts. I. scapularis salivary gland homogenate (SGH) and a group of immunoinformatic-predicted T cell epitopes identified from the I. scapularis salivary transcriptome were used separately to vaccinate HLA DR3 tg mice, and these mice also were assessed for both pathogen protection and epitope recognition. Reduced pathogen transmission along with a Th2 skew resulted from SGH vaccination, while no significant protection and a possible T regulatory bias was seen in epitope-vaccinated mice. This study provides the first proof-of-concept for using HLA DR tg "humanized" mice for studying the potential tick protective effects of immunoinformatic- or otherwise-derived tick salivary

Evaluation of immune response and protective effect of four vaccines against the tick-borne encephalitis virus.

PubMed

Morozova, O V; Bakhvalova, V N; Potapova, O F; Grishechkin, A E; Isaeva, E I; Aldarov, K V; Klinov, D V; Vorovich, M F

2014-05-23

Among three main subtypes of the tick-borne encephalitis virus (TBEV), the Siberian subtype is currently dominant in a majority of the endemic regions of Russia. However, inactivated vaccines are based on TBEV strains of the heterologous Far Eastern or the European subtypes isolated 40-77 years ago. To analyze the efficacy of the available vaccines against currently prevailing TBEV isolates of the Siberian subtype, mice were immunized subcutaneously three times (one group per each vaccine). The expression of seven cytokine genes was determined using RT-PCR. Sera were studied using homologous and heterologous ELISA, hemagglutination inhibition (HI) and neutralization tests with TBEV strains of the Far Eastern, Siberian and European subtypes. Cross-protective efficacy of the vaccines was evaluated with the TBEV strain 2689 of Siberian subtype isolated from an ixodid tick from the Novosibirsk, South-Western Siberia, Russia in 2010. The cytokine gene expression profile indicates a predominantly Th2 response due to exogenous antigen presentation. Titers for homologous combinations of vaccine strain and strain in ELISA, HI and neutralization tests exceeded those for heterologous antigen-antibody pairs. Despite antibody detection by means of ELISA, HI and neutralization tests, the mouse protection afforded by the vaccines differed significantly. Complete protection of mice challenged with 100 LD50 virus of the Siberian subtype was induced by the vaccine "Encevir" ("Microgen", Tomsk, Russia). The minimal immunization doze (MID50) of "Encevir" protecting 50% of the mice was less than 0.0016 ml. Partial protective effect of vaccines produced in Moscow, Russia and Austria revealed MID50 within recommended intervals (0.001-0.017 ml). However, the MID50 for the vaccine "Encepur" (Novartis, Germany) 0.04 ml exceeded acceptable limits with total loss of mice immunized with vaccine diluted 32, 100 and 320 fold. These results suggest regular evaluation of TBEV vaccines in regions

Prime-boost bacillus Calmette-Guérin vaccination with lentivirus-vectored and DNA-based vaccines expressing antigens Ag85B and Rv3425 improves protective efficacy against Mycobacterium tuberculosis in mice.

PubMed

Xu, Ying; Yang, Enzhuo; Wang, Jianguang; Li, Rui; Li, Guanghua; Liu, Guoyuan; Song, Na; Huang, Qi; Kong, Cong; Wang, Honghai

2014-10-01

To prevent the global spread of tuberculosis (TB), more effective vaccines and vaccination strategies are urgently needed. As a result of the success of bacillus Calmette-Guérin (BCG) in protecting children against miliary and meningeal TB, the majority of individuals will have been vaccinated with BCG; hence, boosting BCG-primed immunity will probably be a key component of future vaccine strategies. In this study, we compared the ability of DNA-, protein- and lentiviral vector-based vaccines that express the antigens Ag85B and Rv3425 to boost the effects of BCG in the context of immunity and protection against Mycobacterium tuberculosis in C57BL/6 mice. Our results demonstrated that prime-boost BCG vaccination with a lentiviral vector expressing the antigens Ag85B and Rv3425 significantly enhanced immune responses, including T helper type 1 and CD8(+) cytotoxic T lymphocyte responses, compared with DNA- and protein-based vaccines. However, lentivirus-vectored and DNA-based vaccines greatly improved the protective efficacy of BCG against M. tuberculosis, as indicated by a lack of weight loss and significantly reduced bacterial loads and histological damage in the lung. Our study suggests that the use of lentiviral or DNA vaccines containing the antigens Ag85B and Rv3425 to boost BCG is a good choice for the rational design of an efficient vaccination strategy against TB. © 2014 John Wiley & Sons Ltd.

Intranasal co-administration of 1,8-cineole with influenza vaccine provide cross-protection against influenza virus infection.

PubMed

Li, Yun; Xu, Yu-Ling; Lai, Yan-Ni; Liao, Shang-Hui; Liu, Ni; Xu, Pei-Ping

2017-10-15

Vaccination is the most efficient means for protection against influenza. However, the various vaccines have low efficacy to protect against pandemic strains because of antigenic drift and recombination of influenza virus. Adjuvant therapy is one of the attempts to improve influenza vaccine effective cross-protection against influenza virus infection. Our previous study confirmed that 1,8-cineole inhibits the NF-κB, reduces pro-inflammatory cytokines, and relieves the pathological changes of viral pneumonia in mice infected with influenza virus. 1,8-cineole, administered via intranasal (i.n.) route, may also have the capacity to be an adjuvant of the influenza vaccine. This study was designed to investigate the potential use of i.n. co-administration of 1,8-cineole, a major component of the Eucalyptus essential oils, with influenza vaccine and whether could provide cross-protection against influenza virus infection in a mouse model. I.n. co-administration of 1,8-cineole in two doses (6.25 and 12.5 mg/kg) with influenza vaccine was investigated in a mouse model in order to see whether it could provide cross-protection against influenza virus infection. The mice were intranasally immunized three times at the 0, 7 and 14 day with vaccine containing 0.2 µg hemagglutinin (HA) and/or without 1,8-cineole. Seven days after the 3rd immunization dose, the mice were infected with 50 µl of 15 LD 50 (50% mouse lethal dose) influenza virus A/FM/1/47 (H1N1). On day 6 post-infection, 10 mice per group were sacrificed to collect samples, to take the body weight and lung, and detect the viral load, pathological changes in the lungs and antibody, etc. The collected samples included blood serum and nasal lavage fluids. In addition, the survival experiments were carried out  to investigate the survival of mice. Mice i.n. inoculated with influenza vaccine and 12.5 mg/kg 1,8-cineole increased the production of influenza-specific serum immunoglobulin (Ig) G2a antibodies

Altered methamphetamine place conditioning in mice vaccinated with a succinyl-methamphetamine-tetanus-toxoid vaccine.

PubMed

Haile, Colin N; Kosten, Therese A; Shen, Xiaoyun Y; O'Malley, Patrick W; Winoske, Kevin J; Kinsey, Berma M; Wu, Yan; Huang, Zhen; Lykissa, Ernest D; Naidu, Naga; Cox, Joseph A; Arora, Reetakshi; Kosten, Thomas R; Orson, Frank M

2015-12-01

We previously reported that an anti-methamphetamine (MA) vaccine attenuated drug-conditioned effects in mice, but it used a carrier protein and adjuvant not available for clinical use. Here we produced a vaccine with the same hapten (succinyl-methamphetamine, SMA) but attached to tetanus toxoid (SMA-TT) and adsorbed to aluminum hydroxide, components approved for use in humans. We then assessed the vaccine's ability to generate anti-MA antibodies, alter acquisition and reinstatement of MA place conditioning, and prevent MA brain penetration. Mice were administered SMA-TT at weeks 0 and 3 and non-vaccinated mice received saline. Anti-MA antibody concentrations were determined at 8 and 12 weeks. Place conditioning began during week 9 in which vaccinated and non-vaccinated mice were divided into groups and conditioned with .5, or 2.0 mg/kg MA. Following acquisition training, mice were extinguished and then a reinstatement test was performed in which mice were administered their original training dose of MA. Separate groups of non-vaccinated and vaccinated mice were administered .5 and 2.0 mg/kg MA and brain MA levels determined. Anti-MA antibody levels were elevated at week 8 and remained so through week 12. The SMA-TT vaccine attenuated acquisition and reinstatement of MA place conditioning. Significantly greater proportions of vaccinated mice during acquisition and reinstatement tests showed conditioned place aversion. Moreover, MA brain levels were decreased in vaccinated mice following administration of both doses of MA. Results support further development of anti-MA vaccines using components approved for use in humans. © American Academy of Addiction Psychiatry.

AF03-adjuvanted and non-adjuvanted pandemic influenza A (H1N1) 2009 vaccines induce strong antibody responses in seasonal influenza vaccine-primed and unprimed mice.

PubMed

Caillet, Catherine; Piras, Fabienne; Bernard, Marie-Clotilde; de Montfort, Aymeric; Boudet, Florence; Vogel, Frederick R; Hoffenbach, Agnès; Moste, Catherine; Kusters, Inca

2010-04-19

Pandemic influenza vaccines have been manufactured using the A/California/07/2009 (H1N1) strain as recommended by the World Health Organization. We evaluated in mice the immunogenicity of pandemic (H1N1) 2009 vaccine and the impact of prior vaccination against seasonal trivalent influenza vaccines (TIV) on antibody responses against pandemic (H1N1) 2009. In naïve mice, a single dose of unadjuvanted H1N1 vaccine (3 microg of HA) was shown to elicit hemagglutination inhibition (HI) antibody titers >40, a titer associated with protection in humans against seasonal influenza. A second vaccine dose of pandemic (H1N1) 2009 vaccine strongly increased these titers, which were consistently higher in mice previously primed with TIV than in naïve mice. At a low immunization dose (0.3 microg of HA), the AF03-adjuvanted vaccine elicited higher HI antibody titers than the corresponding unadjuvanted vaccines in both naïve and TIV-primed animals, suggesting a potential for antigen dose-sparing. These results are in accordance with the use in humans of a split-virion inactivated pandemic (H1N1) 2009 vaccine formulated with or without AF03 adjuvant to protect children and young adults against influenza A (H1N1) 2009 infection. Copyright 2010 Elsevier Ltd. All rights reserved.

High Antigen Dose Is Detrimental to Post-Exposure Vaccine Protection against Tuberculosis

PubMed Central

Billeskov, Rolf; Lindenstrøm, Thomas; Woodworth, Joshua; Vilaplana, Cristina; Cardona, Pere-Joan; Cassidy, Joseph P.; Mortensen, Rasmus; Agger, Else Marie; Andersen, Peter

2018-01-01

Mycobacterium tuberculosis (Mtb), the etiologic agent of tuberculosis (TB), causes 1.8M deaths annually. The current vaccine, BCG, has failed to eradicate TB leaving 25% of the world’s population with latent Mtb infection (LTBI), and 5–10% of these people will reactivate and develop active TB. An efficient therapeutic vaccine targeting LTBI could have an enormous impact on global TB incidence, and could be an important aid in fighting multidrug resistance, which is increasing globally. Here we show in a mouse model using the H56 (Ag85B-ESAT-6-Rv2660) TB vaccine candidate that post-exposure, but not preventive, vaccine protection requires low vaccine antigen doses for optimal protection. Loss of protection from high dose post-exposure vaccination was not associated with a loss of overall vaccine response magnitude, but rather with greater differentiation and lower functional avidity of vaccine-specific CD4 T cells. High vaccine antigen dose also led to a decreased ability of vaccine-specific CD4 T cells to home into the Mtb-infected lung parenchyma, a recently discovered important feature of T cell protection in mice. These results underscore the importance of T cell quality rather than magnitude in TB-vaccine protection, and the significant role that antigen dosing plays in vaccine-mediated protection. PMID:29379507

Vaccination with M2e-Based Multiple Antigenic Peptides: Characterization of the B Cell Response and Protection Efficacy in Inbred and Outbred Mice

PubMed Central

Wolf, Amaya I.; Mozdzanowska, Krystyna; Williams, Katie L.; Singer, David; Richter, Monique; Hoffmann, Ralf; Caton, Andrew J.; Otvos, Laszlo; Erikson, Jan

2011-01-01

Background The extracellular domain of the influenza A virus protein matrix protein 2 (M2e) is remarkably conserved between various human isolates and thus is a viable target antigen for a universal influenza vaccine. With the goal of inducing protection in multiple mouse haplotypes, M2e-based multiple antigenic peptides (M2e-MAP) were synthesized to contain promiscuous T helper determinants from the Plasmodium falciparum circumsporozoite protein, the hepatitis B virus antigen and the influenza virus hemagglutinin. Here, we investigated the nature of the M2e-MAP-induced B cell response in terms of the distribution of antibody (Ab) secreting cells (ASCs) and Ab isotypes, and tested the protective efficacy in various mouse strains. Methodology/Principal Findings Immunization of BALB/c mice with M2e-MAPs together with potent adjuvants, CpG 1826 oligonucleotides (ODN) and cholera toxin (CT) elicited high M2e-specific serum Ab titers that protected mice against viral challenge. Subcutaneous (s.c.) and intranasal (i.n.) delivery of M2e-MAPs resulted in the induction of IgG in serum and airway secretions, however only i.n. immunization induced anti-M2e IgA ASCs locally in the lungs, correlating with M2-specific IgA in the bronchio-alveolar lavage (BAL). Interestingly, both routes of vaccination resulted in equal protection against viral challenge. Moreover, M2e-MAPs induced cross-reactive and protective responses to diverse M2e peptides and variant influenza viruses. However, in contrast to BALB/c mice, immunization of other inbred and outbred mouse strains did not induce protective Abs. This correlated with a defect in T cell but not B cell responsiveness to the M2e-MAPs. Conclusion/Significance Anti-M2e Abs induced by M2e-MAPs are highly cross-reactive and can mediate protection to variant viruses. Although synthetic MAPs are promising designs for vaccines, future constructs will need to be optimized for use in the genetically heterogeneous human population. PMID

Vaccination with M2e-based multiple antigenic peptides: characterization of the B cell response and protection efficacy in inbred and outbred mice.

PubMed

Wolf, Amaya I; Mozdzanowska, Krystyna; Williams, Katie L; Singer, David; Richter, Monique; Hoffmann, Ralf; Caton, Andrew J; Otvos, Laszlo; Erikson, Jan

2011-01-01

The extracellular domain of the influenza A virus protein matrix protein 2 (M2e) is remarkably conserved between various human isolates and thus is a viable target antigen for a universal influenza vaccine. With the goal of inducing protection in multiple mouse haplotypes, M2e-based multiple antigenic peptides (M2e-MAP) were synthesized to contain promiscuous T helper determinants from the Plasmodium falciparum circumsporozoite protein, the hepatitis B virus antigen and the influenza virus hemagglutinin. Here, we investigated the nature of the M2e-MAP-induced B cell response in terms of the distribution of antibody (Ab) secreting cells (ASCs) and Ab isotypes, and tested the protective efficacy in various mouse strains. Immunization of BALB/c mice with M2e-MAPs together with potent adjuvants, CpG 1826 oligonucleotides (ODN) and cholera toxin (CT) elicited high M2e-specific serum Ab titers that protected mice against viral challenge. Subcutaneous (s.c.) and intranasal (i.n.) delivery of M2e-MAPs resulted in the induction of IgG in serum and airway secretions, however only i.n. immunization induced anti-M2e IgA ASCs locally in the lungs, correlating with M2-specific IgA in the bronchio-alveolar lavage (BAL). Interestingly, both routes of vaccination resulted in equal protection against viral challenge. Moreover, M2e-MAPs induced cross-reactive and protective responses to diverse M2e peptides and variant influenza viruses. However, in contrast to BALB/c mice, immunization of other inbred and outbred mouse strains did not induce protective Abs. This correlated with a defect in T cell but not B cell responsiveness to the M2e-MAPs. Anti-M2e Abs induced by M2e-MAPs are highly cross-reactive and can mediate protection to variant viruses. Although synthetic MAPs are promising designs for vaccines, future constructs will need to be optimized for use in the genetically heterogeneous human population.

Coadministration of the Three Antigenic Leishmania infantum Poly (A) Binding Proteins as a DNA Vaccine Induces Protection against Leishmania major Infection in BALB/c Mice

PubMed Central

Corvo, Laura; Garde, Esther; Ramírez, Laura; Iniesta, Virginia; Bonay, Pedro; Gómez-Nieto, Carlos; González, Víctor M.; Martín, M. Elena; Alonso, Carlos; Coelho, Eduardo A. F.; Barral, Aldina; Barral-Netto, Manoel

2015-01-01

Background Highly conserved intracellular proteins from Leishmania have been described as antigens in natural and experimental infected mammals. The present study aimed to evaluate the antigenicity and prophylactic properties of the Leishmania infantum Poly (A) binding proteins (LiPABPs). Methodology/Principal Findings Three different members of the LiPABP family have been described. Recombinant tools based on these proteins were constructed: recombinant proteins and DNA vaccines. The three recombinant proteins were employed for coating ELISA plates. Sera from human and canine patients of visceral leishmaniasis and human patients of mucosal leishmaniasis recognized the three LiPABPs. In addition, the protective efficacy of a DNA vaccine based on the combination of the three Leishmania PABPs has been tested in a model of progressive murine leishmaniasis: BALB/c mice infected with Leishmania major. The induction of a Th1-like response against the LiPABP family by genetic vaccination was able to down-regulate the IL-10 predominant responses elicited by parasite LiPABPs after infection in this murine model. This modulation resulted in a partial protection against L. major infection. LiPABP vaccinated mice showed a reduction on the pathology that was accompanied by a decrease in parasite burdens, in antibody titers against Leishmania antigens and in the IL-4 and IL-10 parasite-specific mediated responses in comparison to control mice groups immunized with saline or with the non-recombinant plasmid. Conclusion/Significance The results presented here demonstrate for the first time the prophylactic properties of a new family of Leishmania antigenic intracellular proteins, the LiPABPs. The redirection of the immune response elicited against the LiPABP family (from IL-10 towards IFN-γ mediated responses) by genetic vaccination was able to induce a partial protection against the development of the disease in a highly susceptible murine model of leishmaniasis. PMID:25955652

Broad protection against influenza infection by vectored immunoprophylaxis in mice

PubMed Central

Balazs, Alejandro B.; Bloom, Jesse D.; Hong, Christin M.; Rao, Dinesh S.; Baltimore, David

2014-01-01

Neutralizing antibodies that target epitopes conserved among many strains of influenza virus have been recently isolated from humans. Here we demonstrate that adeno-associated viruses (AAV) encoding two such broadly neutralizing antibodies are protective against diverse influenza strains. Serum from mice that received a single intramuscular AAV injection efficiently neutralized all H1, H2 and H5 influenza strains tested. After infection with diverse strains of H1N1 influenza, treated mice showed minimal weight loss and lung inflammation. Protection lasted for at least 11 months after AAV injection. Notably, even immunodeficient and older mice were protected by this method, suggesting that expression of a monoclonal antibody alone is sufficient to protect mice from illness. If translated to humans, this prophylactic approach may be uniquely capable of protecting immunocompromised or elderly patient populations not reliably protected by existing vaccines. PMID:23728362

Development of Protective Immunity against Inactivated Iranian Isolate of Foot-and-Mouth Disease Virus Type O/IRN/2007 Using Gamma Ray-Irradiated Vaccine on BALB/c Mice and Guinea Pigs.

PubMed

Motamedi-Sedeh, Farahnaz; Soleimanjahi, Hoorieh; Jalilian, Amir Reza; Mahravani, Homayoon; Shafaee, Kamalodin; Sotoodeh, Masood; Taherkarami, Hamdolah; Jairani, Faramarz

2015-01-01

Foot-and-mouth disease virus (FMDV) causes a highly contagious disease in cloven-hoofed animals and is the most damaging disease of livestock worldwide, leading to great economic losses. The aim of this research was the inactivation of FMDV type O/IRN/1/2007 to produce a gamma ray-irradiated (GRI) vaccine in order to immunize mice and guinea pigs. In this research, the Iranian isolated FMDV type O/IRN/1/2007 was irradiated by gamma ray to prepare an inactivated whole virus antigen and formulated as a GRI vaccine with unaltered antigenic characteristics. Immune responses against this vaccine were evaluated on mice and guinea pigs. The comparison of the immune responses between the GRI vaccine and conventional vaccine did not show any significant difference in neutralizing antibody titer, memory spleen T lymphocytes or IFN-γ, IL-4, IL-2 and IL-10 concentrations (p > 0.05). In contrast, there were significant differences in all of the evaluated immune factors between the two vaccinated groups of mice and negative control mice (p < 0.05). The protective dose 50 for the conventional and GRI vaccines obtained were 6.28 and 7.07, respectively, which indicated the high potency of both vaccines. GRI vaccine is suitable for both routine vaccination and control of FMDV in emergency outbreaks.

Detoxified Endotoxin Vaccine (J5dLPS/OMP) Protects Mice Against Lethal Respiratory Challenge with Francisella tularensis SchuS4

PubMed Central

Gregory, Stephen H.; Chen, Wilbur H.; Mott, Stephanie; Palardy, John E.; Parejo, Nicholas A.; Heninger, Sara; Anderson, Christine A.; Artenstein, Andrew W.; Opal, Steven M.; Cross, Alan S.

2010-01-01

Francisella tularensis is a category A select agent. J5dLPS/OMP is a novel vaccine construct consisting of detoxified, O-polysaccharide side chain-deficient, lipopolysaccharide non-covalently complexed with the outer membrane protein of N. meningitidis group B. Immunization elicits hightiter polyclonal antibodies specific for the highly-conserved epitopes expressed within the glycolipid core that constitutes gram-negative bacteria (e.g., F. tularensis). Mice immunized intranasally with J5dLPS/OMP exhibited protective immunity to intratracheal challenge with the live vaccine strain, as well as the highly-virulent SchuS4 strain, of F. tularensis. The efficacy of J5dLPS/OMP vaccine suggests its potential utility in immunizing the general population against several different gram-negative select agents concurrently. PMID:20170768

Burkholderia mallei CLH001 Attenuated Vaccine Strain Is Immunogenic and Protects against Acute Respiratory Glanders

PubMed Central

Hatcher, Christopher L.; Mott, Tiffany M.; Muruato, Laura A.; Sbrana, Elena

2016-01-01

Burkholderia mallei is the causative agent of glanders, an incapacitating disease with high mortality rates in respiratory cases. Its endemicity and ineffective treatment options emphasize its public health threat and highlight the need for a vaccine. Live attenuated vaccines are considered the most viable vaccine strategy for Burkholderia, but single-gene-deletion mutants have not provided complete protection. In this study, we constructed the select-agent-excluded B. mallei ΔtonB Δhcp1 (CLH001) vaccine strain and investigated its ability to protect against acute respiratory glanders. Here we show that CLH001 is attenuated, safe, and effective at protecting against lethal B. mallei challenge. Intranasal administration of CLH001 to BALB/c and NOD SCID gamma (NSG) mice resulted in complete survival without detectable colonization or abnormal organ histopathology. Additionally, BALB/c mice intranasally immunized with CLH001 in a prime/boost regimen were fully protected against lethal challenge with the B. mallei lux (CSM001) wild-type strain. PMID:27271739

Comparability of ELISA and toxin neutralization to measure immunogenicity of Protective Antigen in mice, as part of a potency test for anthrax vaccines.

PubMed

Parreiras, P M; Sirota, L A; Wagner, L D; Menzies, S L; Arciniega, J L

2009-07-16

Complexities of lethal challenge models have prompted the investigation of immunogenicity assays as potency tests of anthrax vaccines. An ELISA and a lethal toxin neutralization assay (TNA) were used to measure antibody response to Protective Antigen (PA) in mice immunized once with either a commercial or a recombinant PA (rPA) vaccine formulated in-house. Even though ELISA and TNA results showed correlation, ELISA results may not be able to accurately predict TNA results in this single immunization model.

Novel Catanionic Surfactant Vesicle Vaccines Protect against Francisella tularensis LVS and Confer Significant Partial Protection against F. tularensis Schu S4 Strain

PubMed Central

Richard, Katharina; Mann, Barbara J.; Stocker, Lenea; Barry, Eileen M.; Qin, Aiping; Cole, Leah E.; Hurley, Matthew T.; Ernst, Robert K.; Michalek, Suzanne M.; Stein, Daniel C.; DeShong, Philip

2014-01-01

Francisella tularensis is a Gram-negative immune-evasive coccobacillus that causes tularemia in humans and animals. A safe and efficacious vaccine that is protective against multiple F. tularensis strains has yet to be developed. In this study, we tested a novel vaccine approach using artificial pathogens, synthetic nanoparticles made from catanionic surfactant vesicles that are functionalized by the incorporation of either F. tularensis type B live vaccine strain (F. tularensis LVS [LVS-V]) or F. tularensis type A Schu S4 strain (F. tularensis Schu S4 [Schu S4-V]) components. The immunization of C57BL/6 mice with “bare” vesicles, which did not express F. tularensis components, partially protected against F. tularensis LVS, presumably through activation of the innate immune response, and yet it failed to protect against the F. tularensis Schu S4 strain. In contrast, immunization with LVS-V fully protected mice against intraperitoneal (i.p.) F. tularensis LVS challenge, while immunization of mice with either LVS-V or Schu S4-V partially protected C57BL/6 mice against an intranasal (i.n.) F. tularensis Schu S4 challenge and significantly increased the mean time to death for nonsurvivors, particularly following the i.n. and heterologous (i.e., i.p./i.n.) routes of immunization. LVS-V immunization, but not immunization with empty vesicles, elicited high levels of IgG against nonlipopolysaccharide (non-LPS) epitopes that were increased after F. tularensis LVS challenge and significantly increased early cytokine production. Antisera from LVS-V-immunized mice conferred passive protection against challenge with F. tularensis LVS. Together, these data indicate that functionalized catanionic surfactant vesicles represent an important and novel tool for the development of a safe and effective F. tularensis subunit vaccine and may be applicable for use with other pathogens. PMID:24351755

Major role for CD8 T cells in the protection against Toxoplasma gondii following dendritic cell vaccination.

PubMed

Guiton, R; Zagani, R; Dimier-Poisson, I

2009-10-01

Toxoplasma gondii is the causative agent of toxoplasmosis, a worldwide zoonosis for which an effective vaccine is needed. Vaccination with pulsed dendritic cells is very efficient but their use in a vaccination protocol is unconceivable. Nevertheless, unravelling the induced effector mechanisms is crucial to design new vaccine strategies. We vaccinated CBA/J mice with parasite extract-pulsed dendritic cells, challenged them with T. gondii cysts and carried out in vivo depletion of CD4(+) or CD8(+) T lymphocytes to study the subsequent cellular immune response and protective mechanisms. CD4(+) lymphocytes were poorly implicated either in spleen and mesenteric lymph node (MLN) cytokine secretion or in mice protection. By contrast, the increasing number of intracerebral cysts and depletion of CD8(+) cells were strongly correlated, revealing a prominent role for CD8(+) lymphocytes in the protection of mice. Splenic CD8(+) lymphocytes induce a strong Th1 response controlled by a Th2 response whereas CD8(+) cells from MLNs inhibit both Th1 and Th2 responses. CD8(+) cells are the main effectors following dendritic cell vaccination and Toxoplasma infection while CD4(+) T cells only play a minor role. This contrasts with T. gondii infection which elicits the generation of CD4(+) and CD8(+) T cells that provide protective immunity.

MPT-51/CpG DNA vaccine protects mice against Mycobacterium tuberculosis.

PubMed

Silva, Bruna Daniella de Souza; da Silva, Ediane Batista; do Nascimento, Ivan Pereira; Dos Reis, Michelle Cristina Guerreiro; Kipnis, André; Junqueira-Kipnis, Ana Paula

2009-07-16

Tuberculosis (TB) is a severe infectious disease that kills approximately two million people worldwide every year. Because BCG protection is variable and does not protects adults, there is a great need for a new vaccine against TB that does not represent a risk for immunocompromised patients and that is also capable of protecting adult individuals. MPT-51 is a protein found in the genome of mycobacteria and binds to the fibronectin of the extracellular matrix, which may have a role in host tissue attachment and virulence. In order to test the usefulness of MPT-51 as a subunit vaccine, BALB/c were vaccinated and challenged with Mycobacterium tuberculosis. The infection of BALB/c with M. tuberculosis increased the number of IFN-gamma(+) T lymphocytes specific to MPT-51 in the spleen and lungs. Inoculation with rMPT-51/FIA and with rMPT-51/CpG DNA in non-infected BALB/c increased the amounts of IFN-gamma(+) T lymphocytes. Inoculation with rMPT-51/FIA also induced a humoral response specific to MPT-51. CFU counts of lung tissues done 60 days after infection showed a reduction of about 2 log in the bacteria load in the group of animals inoculated with rMPT-51/CpG DNA. These results make MPT-51 a valuable component to be further evaluated in the development of other subunit vaccines.

Saccharomyces cerevisiae expressing Gp43 protects mice against Paracoccidioides brasiliensis infection.

PubMed

Assis-Marques, Mariana Aprigio; Oliveira, Aline Ferreira; Ruas, Luciana Pereira; dos Reis, Thaila Fernanda; Roque-Barreira, Maria Cristina; Coelho, Paulo Sergio Rodrigues

2015-01-01

The dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis (PCM). It is believed that approximately 10 million people are infected with the fungus and approximately 2% will eventually develop the disease. Unlike viral and bacterial diseases, fungal diseases are the ones against which there is no commercially available vaccine. Saccharomyces cerevisiae may be a suitable vehicle for immunization against fungal infections, as they require the stimulation of different arms of the immune response. Here we evaluated the efficacy of immunizing mice against PCM by using S. cerevisiae yeast expressing gp43. When challenged by inoculation of P. brasiliensis yeasts, immunized animals showed a protective profile in three different assays. Their lung parenchyma was significantly preserved, exhibiting fewer granulomas with fewer fungal cells than found in non-immunized mice. Fungal burden was reduced in the lung and spleen of immunized mice, and both organs contained higher levels of IL-12 and IFN-γ compared to those of non-vaccinated mice, a finding that suggests the occurrence of Th1 immunity. Taken together, our results indicate that the recombinant yeast vaccine represents a new strategy to confer protection against PCM.

Microneedle delivery of trivalent influenza vaccine to the skin induces long-term cross-protection.

PubMed

Kim, Yeu-Chun; Lee, Su-Hwa; Choi, Won-Hyung; Choi, Hyo-Jick; Goo, Tae-Won; Lee, Ju-Hie; Quan, Fu-Shi

2016-12-01

A painless self-immunization method with effective and broad cross-protection is urgently needed to prevent infections against newly emerging influenza viruses. In this study, we investigated the cross-protection efficacy of trivalent influenza vaccine containing inactivated A/PR/8/34 (H1N1), A/Hong Kong/68 (H3N2) and B/Lee/40 after skin vaccination using microneedle patches coated with this vaccine. Microneedle vaccination of mice in the skin provided 100% protection against lethal challenges with heterologous pandemic strain influenza A/California/04/09, heterogeneous A/Philippines/2/82 and B/Victoria/287 viruses 8 months after boost immunization. Cross-reactive serum IgG antibody responses against heterologous influenza viruses A/California/04/09, A/Philippines/2/82 and B/Victoria/287 were induced at high levels. Hemagglutination inhibition titers were also maintained at high levels against these heterogeneous viruses. Microneedle vaccination induced substantial levels of cross-reactive IgG antibody responses in the lung and cellular immune responses, as well as cross-reactive antibody-secreting plasma cells in the spleen. Viral loads in the lung were significantly (p < 0.05) reduced. All mice survived after viral challenges. These results indicate that skin vaccination with trivalent vaccine using a microneedle array could provide protection against seasonal epidemic or new pandemic strain of influenza viruses.

Protective immunity spectrum induced by immunization with a vaccine from the TBEV strain Sofjin.

PubMed

Chernokhaeva, L L; Rogova, Yu V; Vorovitch, M F; Romanova, L Iu; Kozlovskaya, L I; Maikova, G B; Kholodilov, I S; Karganova, G G

2016-04-29

Tick-borne encephalitis (TBE) circulates widely in the territory of Eurasia with up to 10,000 cases registered annually. The TBE virus (TBEV) includes three main subtypes: European, Siberian and Far-Eastern, and two new Asiatic variants, phylogenetically distant from the others. The inactivated antigen of European or Far-Eastern strains is used in commercial TBE vaccines. A set of 14 TBEV strains, isolated in 1937-2008, with different passage histories, representing all subtypes and variants, was used in this work. The chosen set covers almost all the TBE area. Sera of mice, immunized with the TBE vaccine Moscow, prepared from the TBEV strain Sofjin, were studied in a plaque neutralization test against the set of TBEV strains. The vaccine induced antibodies at a protective titer against all TBEV strains and Omsk hemorrhagic fever virus (OHFV) with Е protein amino acid distances of 0.008-0.069, but not against Powassan virus. We showed that after a course of two immunizations, factors such as the period between vaccinations (1-4 weeks), the challenging virus dose (30-1000 LD50) and terms of challenge (1-4 weeks after the last immunization) did not significantly affect the assessment of protective efficacy of the vaccine in vivo. The protective effect of the TBE vaccine Moscow against the set of TBEV strains and the OHFV was demonstrated in in vivo experiments. TBE vaccine Moscow did not protect mice against 10 LD50 of the Powassan virus. We showed that this range of Е protein amino acid distances between the vaccine strain and challenging virus do not have a decisive impact on the TBE vaccine protective effect in vitro and in vivo. Moreover, the TBE vaccine Moscow induces an immune response protective against a wide range of TBEV variants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immunization with vesicular stomatitis virus vaccine expressing the Ebola glycoprotein provides sustained long-term protection in rodents.

PubMed

Wong, Gary; Audet, Jonathan; Fernando, Lisa; Fausther-Bovendo, Hugues; Alimonti, Judie B; Kobinger, Gary P; Qiu, Xiangguo

2014-09-29

Ebola virus (EBOV) infections cause lethal hemorrhagic fever in humans, resulting in up to 90% mortality. EBOV outbreaks are sporadic and unpredictable in nature; therefore, a vaccine that is able to provide durable immunity is needed to protect those who are at risk of exposure to the virus. This study assesses the long-term efficacy of the vesicular stomatitis virus (VSV)-based vaccine (VSVΔG/EBOVGP) in two rodent models of EBOV infection. Mice and guinea pigs were first immunized with 2×10(4) or 2×10(5) plaque forming units (PFU) of VSVΔG/EBOVGP, respectively. Challenge of mice with a lethal dose of mouse-adapted EBOV (MA-EBOV) at 6.5 and 9 months after vaccination provided complete protection, and 80% (12 of 15 survivors) protection at 12 months after vaccination. Challenge of guinea pigs with a lethal dose of guinea pig-adapted EBOV (GA-EBOV) at 7, 12 and 18 months after vaccination resulted in 83% (5 of 6 survivors) at 7 months after vaccination, and 100% survival at 12 and 18 months after vaccination. No weight loss or clinical signs were observed in the surviving animals. Antibody responses were analyzed using sera from individual rodents. Levels of EBOV glycoprotein-specific IgG antibody measured immediately before challenge appeared to correlate with protection. These studies confirm that vaccination with VSVΔG/EBOVGP is able to confer long-term protection against Ebola infection in mice and guinea pigs, and support follow-up studies in non-human primates. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Brucella lipopolysaccharide reinforced Salmonella delivering Brucella immunogens protects mice against virulent challenge.

PubMed

Lalsiamthara, Jonathan; Lee, John Hwa

2017-06-01

Intracellular pathogen Salmonella exhibits natural infection broadly analogous to Brucella, this phenomenon makes Salmonella a pragmatic choice for an anti-Brucella vaccine delivery platform. In this study we developed and formulated a combination of four attenuated Salmonella Typhimurium live vector strains delivering heterologous Brucella antigens (rBs), namely lumazine synthase, proline racemase subunit A, lipoprotein outer membrane protein-19, and Cu-Zn superoxide dismutase. With an aim to develop a cross-protecting vaccine, Brucella pan-species conserved rBs were selected. The present study compared the efficacy of smooth and rough variants of Salmonella delivery vector and also evaluated the inclusion of purified Brucella lipopolysaccharide (LPS) in the formulation. Immunization of SPF-BALB/c mice with the vaccine combinations significantly (P≤0.05) reduced splenic wild-type Brucella abortus 544 colonization as compared to non-immunized mice as well as Salmonella only immunized mice. Increased induction of Brucella specific-IgG, sIgA production, and antigen-specific splenocyte proliferative responses were observed in the mice immunized with the formulations as compared to naïve or vector only immunized mice. Modulatory effects of rB and LPS on production of interleukin (IL)-4, IL-12, and interferon-γ were detected in splenocytes of mice immunized with the formulation. Rough Salmonella variant in combination with LPS could further enhance the efficacy of the delivery when applied intraperitoneally. Taken together, it is compelling that Brucella LPS-augmented Salmonella vector delivering immunogenic Brucella proteins may be more suitable than the current non-ideal live Brucella abortus vaccine. The vaccine system also provides a basis for the development of cross-protecting vaccine capable of preventing multispecies brucellosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Defective anti-polysaccharide IgG vaccine responses in IgA deficient mice.

PubMed

Furuya, Yoichi; Kirimanjeswara, Girish S; Roberts, Sean; Racine, Rachael; Wilson-Welder, Jennifer; Sanfilippo, Alan M; Salmon, Sharon L; Metzger, Dennis W

2017-09-05

We report that IgA -/- mice exhibit specific defects in IgG antibody responses to various polysaccharide vaccines (Francisella tularensis LPS and Pneumovax), but not protein vaccines such as Fluzone. This defect further included responses to polysaccharide-protein conjugate vaccines (Prevnar and Haemophilus influenzae type b-tetanus toxoid vaccine). In agreement with these findings, IgA -/- mice were protected from pathogen challenge with protein- but not polysaccharide-based vaccines. Interestingly, after immunization with live bacteria, IgA +/+ and IgA -/- mice were both resistant to lethal challenge and their IgG anti-polysaccharide antibody responses were comparable. Immunization with live bacteria, but not purified polysaccharide, induced production of serum B cell-activating factor (BAFF), a cytokine important for IgG class switching; supplementing IgA -/- cell cultures with BAFF enhanced in vitro polyclonal IgG production. Taken together, these findings show that IgA deficiency impairs IgG class switching following vaccination with polysaccharide antigens and that live bacterial immunization can overcome this defect. Since IgA deficient patients also often show defects in antibody responses following immunization with polysaccharide vaccines, our findings could have relevance to the clinical management of this population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Protein-energy malnutrition alters IgA responses to rotavirus vaccination and infection but does not impair vaccine efficacy in mice

PubMed Central

Maier, Elizabeth A.; Weage, Kristina J.; Guedes, Marjorie M; Denson, Lee A.; McNeal, Monica M.; Bernstein, David I.; Moore, Sean R.

2013-01-01

Background Conflicting evidence links malnutrition to the reduced efficacy of rotavirus vaccines in developing countries, where diarrhea and undernutrition remain leading causes of child deaths. Here, we adapted mouse models of rotavirus vaccination (rhesus rotavirus, RRV), rotavirus infection (EDIM), and protein-energy malnutrition (PEM) to test the hypothesis that undernutrition reduces rotavirus vaccine immunogenicity and efficacy. Methods We randomized wild type Balb/C dams with 3-day-old pups to a control diet (CD) or an isocaloric, multideficient regional basic diet (RBD) that produces PEM. At 3 weeks of age, we weaned CD and RBD pups to their dams’ diet and subrandomized weanlings to receive a single dose of either live oral rotavirus vaccine (RRV) or PBS. At 6 weeks of age, we orally challenged all groups with murine rotavirus (EDIM). Serum and stool specimens were collected before and after RRV and EDIM administration to measure viral shedding and antibody responses by ELISA. Results RBD pups and weanlings exhibited significant failure to thrive compared to age-matched CD mice (P<.0001). RRV vaccination induced higher levels of serum anti-RV IgA responses in RBD vs. CD mice (P<.0001). Vaccination protected CD and RBD mice equally against EDIM infection, as measured by viral shedding. In unvaccinated RBD mice, EDIM shedding peaked 1 day earlier (P<.05), however we detected no effects of undernutrition on viral clearance nor of infection on bodyweight. EDIM infection provoked higher anti-RV serum IgA levels in RBD vs. CD mice, regardless of vaccination (P<.0001). Last, RRV vaccination mitigated stool IgA responses to EDIM more in CD vs. RBD mice (P<.0001). Conclusions Despite modulated IgA responses to vaccination and infection, undernutrition does not impair rotavirus vaccine efficacy nor exacerbate infection in this mouse model of protein-energy malnutrition. Alternative models are needed to elucidate host-pathogen factors undermining rotavirus vaccine

Protein-energy malnutrition alters IgA responses to rotavirus vaccination and infection but does not impair vaccine efficacy in mice.

PubMed

Maier, Elizabeth A; Weage, Kristina J; Guedes, Marjorie M; Denson, Lee A; McNeal, Monica M; Bernstein, David I; Moore, Sean R

2013-12-17

Conflicting evidence links malnutrition to the reduced efficacy of rotavirus vaccines in developing countries, where diarrhea and undernutrition remain leading causes of child deaths. Here, we adapted mouse models of rotavirus vaccination (rhesus rotavirus, RRV), rotavirus infection (EDIM), and protein-energy malnutrition (PEM) to test the hypothesis that undernutrition reduces rotavirus vaccine immunogenicity and efficacy. We randomized wild type Balb/C dams with 3-day-old pups to a control diet (CD) or an isocaloric, multideficient regional basic diet (RBD) that produces PEM. At 3 weeks of age, we weaned CD and RBD pups to their dams' diet and subrandomized weanlings to receive a single dose of either live oral rotavirus vaccine (RRV) or PBS. At 6 weeks of age, we orally challenged all groups with murine rotavirus (EDIM). Serum and stool specimens were collected before and after RRV and EDIM administration to measure viral shedding and antibody responses by ELISA. RBD pups and weanlings exhibited significant failure to thrive compared to age-matched CD mice (P<.0001). RRV vaccination induced higher levels of serum anti-RV IgA responses in RBD vs. CD mice (P<.0001). Vaccination protected CD and RBD mice equally against EDIM infection, as measured by viral shedding. In unvaccinated RBD mice, EDIM shedding peaked 1 day earlier (P<.05), however we detected no effects of undernutrition on viral clearance nor of infection on bodyweight. EDIM infection provoked higher anti-RV serum IgA levels in RBD vs. CD mice, regardless of vaccination (P<.0001). Last, RRV vaccination mitigated stool IgA responses to EDIM more in CD vs. RBD mice (P<.0001). Despite modulated IgA responses to vaccination and infection, undernutrition does not impair rotavirus vaccine efficacy nor exacerbate infection in this mouse model of protein-energy malnutrition. Alternative models are needed to elucidate host-pathogen factors undermining rotavirus vaccine effectiveness in high-risk global settings

Lack of Cross-protection against Bordetella holmesii after Pertussis Vaccination

PubMed Central

Zhang, Xuqing; Weyrich, Laura S.; Lavine, Jennie S.; Karanikas, Alexia T.

2012-01-01

Bordetella holmesii, a species closely related to B. pertussis, has been reported sporadically as a cause of whooping cough–like symptoms. To investigate whether B. pertussis–induced immunity is protective against infection with B. holmesii, we conducted an analysis using 11 human respiratory B. holmesii isolates collected during 2005–2009 from a highly B. pertussis–vaccinated population in Massachusetts. Neither whole-cell (wP) nor acellular (aP) B. pertussis vaccination conferred protection against these B. holmesii isolates in mice. Although T-cell responses induced by wP or aP cross-reacted with B. holmesii, vaccine-induced antibodies failed to efficiently bind B. holmesii. B. holmesii–specific antibodies provided in addition to wP were sufficient to rapidly reduce B. holmesii numbers in mouse lungs. Our findings suggest the established presence of B. holmesii in Massachusetts and that failure to induce cross-reactive antibodies may explain poor vaccine-induced cross-protection. PMID:23092514

Efficacy of rabies vaccines in dogs and cats and protection in a mouse model against European bat lyssavirus type 2.

PubMed

Nokireki, Tiina; Jakava-Viljanen, Miia; Virtala, Anna-Maija; Sihvonen, Liisa

2017-10-02

Rabies is preventable by pre- and/or post-exposure prophylaxis consisting of series of rabies vaccinations and in some cases the use of immunoglobulins. The success of vaccination can be estimated either by measuring virus neutralising antibodies or by challenge experiment. Vaccines based on rabies virus offer cross-protection against other lyssaviruses closely related to rabies virus. The aim was to assess the success of rabies vaccination measured by the antibody response in dogs (n = 10,071) and cats (n = 722), as well as to investigate the factors influencing the response to vaccination when animals failed to reach a rabies antibody titre of ≥ 0.5 IU/ml. Another aim was to assess the level of protection afforded by a commercial veterinary rabies vaccine against intracerebral challenge in mice with European bat lyssavirus type 2 (EBLV-2) and classical rabies virus (RABV), and to compare this with the protection offered by a vaccine for humans. A significantly higher proportion of dogs (10.7%, 95% confidence interval CI 10.1-11.3) than cats (3.5%; 95% CI 2.3-5.0) had a vaccination antibody titre of < 0.5 IU/ml. In dogs, vaccination with certain vaccines, vaccination over 6 months prior the time of antibody determination and vaccination of dogs with a size of > 60 cm or larger resulted in a higher risk of failing to reach an antibody level of at least 0.5 IU/ml. When challenged with EBLV-2 and RABV, 80 and 100% of mice vaccinated with the veterinary rabies vaccine survived, respectively. When mice were vaccinated with the human rabies vaccine and challenged with EBLV-2, 75-80% survived, depending on the booster. All vaccinated mice developed sufficient to high titres of virus-neutralising antibodies (VNA) against RABV 21-22 days post-vaccination, ranging from 0.5 to 128 IU/ml. However, there was significant difference between antibody titres after vaccinating once in comparison to vaccinating twice (P < 0.05). There was a significant difference

Protective effect of enterovirus‑71 (EV71) virus‑like particle vaccine against lethal EV71 infection in a neonatal mouse model.

PubMed

Cao, Lei; Mao, Fengfeng; Pang, Zheng; Yi, Yao; Qiu, Feng; Tian, Ruiguang; Meng, Qingling; Jia, Zhiyuan; Bi, Shengli

2015-08-01

Enterovirus-71 (EV71) is a viral pathogen that causes severe cases of hand, foot and mouth disease (HFMD) among young children, with significant mortality. Effective vaccines against HFMD are urgently required. Several EV71 virus-like particle (VLP) vaccine candidates were found to be protective in the neonatal mouse EV71 challenge model. However, to what extent the VLP vaccine protects susceptible organs against EV71 infection in vivo has remained elusive. In the present study, the comprehensive immunogenicity of a potential EV71 vaccine candidate based on VLPs was evaluated in a neonatal mouse model. Despite lower levels of neutralizing antibodies to EV71 in the sera of VLP-immunized mice compared with those in mice vaccinated with inactivated EV71, the VLP-based vaccine was shown to be able to induce immunoglobulin (Ig)G and IgA memory-associated cellular immune responses to EV71. Of note, the EV71 VLP vaccine candidate was capable of inhibiting viral proliferation in cardiac muscle, skeletal muscle, lung and intestine of immunized mice and provided effective protection against the pathological damage caused by viral attack. In particular, the VLP vaccine was able to inhibit the transportation of EV71 from the central nervous system to the muscle tissue and greatly protected muscle tissue from infection, along with recovery from the viral infection. This led to nearly 100% immunoprotective efficacy, enabling neonatal mice delivered by VLP-immunized female adult mice to survive and grow with good health. The present study provided valuable additional knowledge of the specific protective efficacy of the EV71 VLP vaccine in vivo, which also indicated that it is a promising potential candidate for being developed into an EV71 vaccine.

Heterogeneity in the A33 protein impacts the cross-protective efficacy of a candidate smallpox DNA vaccine.

PubMed

Golden, Joseph W; Hooper, Jay W

2008-07-20

We previously developed a gene-based vaccine, termed 4pox, which targets four orthopoxvirus proteins (A33, L1, B5, and A27). Because any subunit orthopoxvirus vaccine must protect against multiple species of orthopoxviruses, we are interested in understanding the cross-protective potential of our 4pox vaccine target immunogens. In our current studies, we focused on the A33 immunogen. We found one monoclonal antibody against A33, MAb-1G10, which could not bind the monkeypox virus A33 ortholog, A35. MAb-1G10 binding could be rescued if A35 amino acids 118 and 120 were substituted with those from A33. MAb-1G10 has been shown to protect mice from VACV challenge, thus our findings indicated a protective epitope differs among orthopoxviruses. Accordingly, we tested the cross-protective efficacy of a DNA vaccine consisting of A35R against VACV challenge and compared it to vaccination with A33R DNA. Mice vaccinated with A35R had greater mortality and more weight loss compared to those vaccinated with A33R. These findings demonstrate that despite high homology between A33R orthologs, amino acid differences can impact cross-protection. Furthermore, our results caution that adequate cross-protection by any pan-orthopoxvirus subunit vaccine will require not only careful evaluation of cross-protective immunity, but also of targeting of multiple orthopoxvirus immunogens.

DNA vaccine encoding central conserved region of G protein induces Th1 predominant immune response and protection from RSV infection in mice.

PubMed

Hua, Ying; Jiao, Yue-Ying; Ma, Yao; Peng, Xiang-Lei; Fu, Yuan-Hui; Zheng, Yan-Peng; Hong, Tao; He, Jin-Sheng

2016-11-01

Human respiratory syncytial virus (RSV) can cause serious infection in the lower respiratory tract, especially in infants, young children, the elderly and the immunocompromised population worldwide. Previous study demonstrated the polypeptide (amino acids 148-198) of RSV attachment (G) glycoprotein, corresponding to the central conserved region and encompassing CX3C chemokine motif, could induce antibodies and protection from RSV challenge in mice [1,2]. In this study, we evaluated the immune efficacy of the recombinant DNA vaccine of pVAX1/3G 148-198 encoding RSV G protein polypeptide. RSV specific serum IgG antibodies with neutralizing activity were stimulated following prime-boost immunization of pVAX1/3G 148-198 intramuscularly, and the ratio of IgG2a/IgG1 was 4.93, indicating a Th1 biased immune response. After challenged intranasally with RSV Long, the vaccinated mice showed both decreased lung RSV titers, pulmonary inflammation and body weight loss. The results suggest that pVAX1/3G 148-198 DNA vaccine may be an effective RSV vaccine candidate, and deserves further exploration. Copyright © 2016 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

Vaccine Efficacy in Senescent Mice Challenged with Recombinant SARS-CoV Bearing Epidemic and Zoonotic Spike Variants

PubMed Central

Deming, Damon; Sheahan, Timothy; Heise, Mark; Yount, Boyd; Davis, Nancy; Sims, Amy; Suthar, Mehul; Harkema, Jack; Whitmore, Alan; Pickles, Raymond; West, Ande; Donaldson, Eric; Curtis, Kristopher; Johnston, Robert; Baric, Ralph

2006-01-01

Background In 2003, severe acute respiratory syndrome coronavirus (SARS-CoV) was identified as the etiological agent of severe acute respiratory syndrome, a disease characterized by severe pneumonia that sometimes results in death. SARS-CoV is a zoonotic virus that crossed the species barrier, most likely originating from bats or from other species including civets, raccoon dogs, domestic cats, swine, and rodents. A SARS-CoV vaccine should confer long-term protection, especially in vulnerable senescent populations, against both the 2003 epidemic strains and zoonotic strains that may yet emerge from animal reservoirs. We report the comprehensive investigation of SARS vaccine efficacy in young and senescent mice following homologous and heterologous challenge. Methods and Findings Using Venezuelan equine encephalitis virus replicon particles (VRP) expressing the 2003 epidemic Urbani SARS-CoV strain spike (S) glycoprotein (VRP-S) or the nucleocapsid (N) protein from the same strain (VRP-N), we demonstrate that VRP-S, but not VRP-N vaccines provide complete short- and long-term protection against homologous strain challenge in young and senescent mice. To test VRP vaccine efficacy against a heterologous SARS-CoV, we used phylogenetic analyses, synthetic biology, and reverse genetics to construct a chimeric virus (icGDO3-S) encoding a synthetic S glycoprotein gene of the most genetically divergent human strain, GDO3, which clusters among the zoonotic SARS-CoV. icGD03-S replicated efficiently in human airway epithelial cells and in the lungs of young and senescent mice, and was highly resistant to neutralization with antisera directed against the Urbani strain. Although VRP-S vaccines provided complete short-term protection against heterologous icGD03-S challenge in young mice, only limited protection was seen in vaccinated senescent animals. VRP-N vaccines not only failed to protect from homologous or heterologous challenge, but resulted in enhanced immunopathology with

A protective role of murine langerin+ cells in immune responses to cutaneous vaccination with microneedle patches

PubMed Central

Pulit-Penaloza, Joanna A.; Esser, E. Stein; Vassilieva, Elena V.; Lee, Jeong Woo; Taherbhai, Misha T.; Pollack, Brian P.; Prausnitz, Mark R.; Compans, Richard W.; Skountzou, Ioanna

2014-01-01

Cutaneous vaccination with microneedle patches offers several advantages over more frequently used approaches for vaccine delivery, including improved protective immunity. However, the involvement of specific APC subsets and their contribution to the induction of immunity following cutaneous vaccine delivery is not well understood. A better understanding of the functions of individual APC subsets in the skin will allow us to target specific skin cell populations in order to further enhance vaccine efficacy. Here we use a Langerin-EGFP-DTR knock-in mouse model to determine the contribution of langerin+ subsets of skin APCs in the induction of adaptive immune responses following cutaneous microneedle delivery of influenza vaccine. Depletion of langerin+ cells prior to vaccination resulted in substantial impairment of both Th1 and Th2 responses, and decreased post-challenge survival rates, in mice vaccinated cutaneously but not in those vaccinated via the intramuscular route or in non-depleted control mice. Our results indicate that langerin+ cells contribute significantly to the induction of protective immune responses following cutaneous vaccination with a subunit influenza vaccine. PMID:25130187

Cross-protective immunity against influenza A/H1N1 virus challenge in mice immunized with recombinant vaccine expressing HA gene of influenza A/H5N1 virus

PubMed Central

2013-01-01

Background Influenza virus undergoes constant antigenic evolution, and therefore influenza vaccines must be reformulated each year. Time is necessary to produce a vaccine that is antigenically matched to a pandemic strain. A goal of many research works is to produce universal vaccines that can induce protective immunity to influenza A viruses of various subtypes. Despite intensive studies, the precise mechanisms of heterosubtypic immunity (HSI) remain ambiguous. Method In this study, mice were vaccinated with recombinant virus vaccine (rL H5), in which the hemagglutinin (HA) gene of influenza A/H5N1 virus was inserted into the LaSota Newcastle disease virus (NDV) vaccine strain. Following a challenge with influenza A/H1N1 virus, survival rates and lung index of mice were observed. The antibodies to influenza virus were detected using hemagglutination inhibition (HI). The lung viral loads, lung cytokine levels and the percentages of both IFN-γ+CD4+ and IFN-γ+CD8+ T cells in spleen were detected using real-time RT-PCR, ELISA and flow cytometry respectively. Results In comparison with the group of mice given phosphate-buffered saline (PBS), the mice vaccinated with rL H5 showed reductions in lung index and viral replication in the lungs after a challenge with influenza A/H1N1 virus. The antibody titer in group 3 (H1N1-H1N1) was significantly higher than that in other groups which only low levels of antibody were detected. IFN-γ levels increased in both group 1 (rL H5-H1N1) and group 2 (rL H5 + IL-2-H1N1). And the IFN-γ level of group 2 was significantly higher than that of group 1. The percentages of both IFN-γ+CD4+ and IFN-γ+CD8+ T cells in group 1 (rL H5-H1N1) and group 2 (rL H5 + IL-2-H1N1) increased significantly, as measured by flow cytometry. Conclusion After the mice were vaccinated with rL H5, cross-protective immune response was induced, which was against heterosubtypic influenza A/H1N1 virus. To some extent, cross-protective immune response can

Vaccination with plasmid DNA encoding TSA/LmSTI1 leishmanial fusion proteins confers protection against Leishmania major infection in susceptible BALB/c mice.

PubMed

Campos-Neto, A; Webb, J R; Greeson, K; Coler, R N; Skeiky, Y A W; Reed, S G

2002-06-01

We have recently shown that a cocktail containing two leishmanial recombinant antigens (LmSTI1 and TSA) and interleukin-12 (IL-12) as an adjuvant induces solid protection in both a murine and a nonhuman primate model of cutaneous leishmaniasis. However, because IL-12 is difficult to prepare, is expensive, and does not have the stability required for a vaccine product, we have investigated the possibility of using DNA as an alternative means of inducing protective immunity. Here, we present evidence that the antigens TSA and LmSTI1 delivered in a plasmid DNA format either as single genes or in a tandem digene construct induce equally solid protection against Leishmania major infection in susceptible BALB/c mice. Immunization of mice with either TSA DNA or LmSTI1 DNA induced specific CD4(+)-T-cell responses of the Th1 phenotype without a requirement for specific adjuvant. CD8 responses, as measured by cytotoxic-T-lymphocyte activity, were generated after immunization with TSA DNA but not LmSTI1 DNA. Interestingly, vaccination of mice with TSA DNA consistently induced protection to a much greater extent than LmSTI1 DNA, thus supporting the notion that CD8 responses might be an important accessory arm of the immune response for acquired resistance against leishmaniasis. Moreover, the protection induced by DNA immunization was specific for infection with Leishmania, i.e., the immunization had no effect on the course of infection of the mice challenged with an unrelated intracellular pathogen such as Mycobacterium tuberculosis. Conversely, immunization of BALB/c mice with a plasmid DNA that is protective against challenge with M. tuberculosis had no effect on the course of infection of these mice with L. major. Together, these results indicate that the protection observed with the leishmanial DNA is mediated by acquired specific immune response rather than by the activation of nonspecific innate immune mechanisms. In addition, a plasmid DNA containing a fusion construct

Monoclonal Antibodies Passively Protect BALB/c Mice Against Burkholderia mallei Aerosol Challenge

DTIC Science & Technology

2006-03-01

November 2005 Glanders is a debilitating disease with no vaccine available. Murine monoclonal antibodies were produced against Burkholderia mallei , the... Glanders is a debilitating disease with no vaccine available. Murine monoclonal antibodies were produced against Burkholderia mallei , the etiologic... Burkholderia mallei auxotroph protects against aerosol-initiated glanders in mice. Vaccine 23:1986–1992. 17. Vyshelesskii, S. N. 1974. Glanders (Equinia). Tr

Burkholderia mallei CLH001 Attenuated Vaccine Strain Is Immunogenic and Protects against Acute Respiratory Glanders.

PubMed

Hatcher, Christopher L; Mott, Tiffany M; Muruato, Laura A; Sbrana, Elena; Torres, Alfredo G

2016-08-01

Burkholderia mallei is the causative agent of glanders, an incapacitating disease with high mortality rates in respiratory cases. Its endemicity and ineffective treatment options emphasize its public health threat and highlight the need for a vaccine. Live attenuated vaccines are considered the most viable vaccine strategy for Burkholderia, but single-gene-deletion mutants have not provided complete protection. In this study, we constructed the select-agent-excluded B. mallei ΔtonB Δhcp1 (CLH001) vaccine strain and investigated its ability to protect against acute respiratory glanders. Here we show that CLH001 is attenuated, safe, and effective at protecting against lethal B. mallei challenge. Intranasal administration of CLH001 to BALB/c and NOD SCID gamma (NSG) mice resulted in complete survival without detectable colonization or abnormal organ histopathology. Additionally, BALB/c mice intranasally immunized with CLH001 in a prime/boost regimen were fully protected against lethal challenge with the B. mallei lux (CSM001) wild-type strain. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Protection against Experimental Cryptococcosis following Vaccination with Glucan Particles Containing Cryptococcus Alkaline Extracts.

PubMed

Specht, Charles A; Lee, Chrono K; Huang, Haibin; Tipper, Donald J; Shen, Zu T; Lodge, Jennifer K; Leszyk, John; Ostroff, Gary R; Levitz, Stuart M

2015-12-22

A vaccine capable of protecting at-risk persons against infections due to Cryptococcus neoformans and Cryptococcus gattii could reduce the substantial global burden of human cryptococcosis. Vaccine development has been hampered though, by lack of knowledge as to which antigens are immunoprotective and the need for an effective vaccine delivery system. We made alkaline extracts from mutant cryptococcal strains that lacked capsule or chitosan. The extracts were then packaged into glucan particles (GPs), which are purified Saccharomyces cerevisiae cell walls composed primarily of β-1,3-glucans. Subcutaneous vaccination with the GP-based vaccines provided significant protection against subsequent pulmonary infection with highly virulent strains of C. neoformans and C. gattii. The alkaline extract derived from the acapsular strain was analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS), and the most abundant proteins were identified. Separation of the alkaline extract by size exclusion chromatography revealed fractions that conferred protection when loaded in GP-based vaccines. Robust Th1- and Th17-biased CD4(+) T cell recall responses were observed in the lungs of vaccinated and infected mice. Thus, our preclinical studies have indicated promising cryptococcal vaccine candidates in alkaline extracts delivered in GPs. Ongoing studies are directed at identifying the individual components of the extracts that confer protection and thus would be promising candidates for a human vaccine. The encapsulated yeast Cryptococcus neoformans and its closely related sister species, Cryptococcus gattii, are major causes of morbidity and mortality, particularly in immunocompromised persons. This study reports on the preclinical development of vaccines to protect at-risk populations from cryptococcosis. Antigens were extracted from Cryptococcus by treatment with an alkaline solution. The extracted antigens were then packaged into glucan particles, which are hollow

Recombinant Zika virus envelope protein elicited protective immunity against Zika virus in immunocompetent mice

PubMed Central

Liu, Zhihua; Li, Min; Liu, Haitao

2018-01-01

Zika virus (ZIKV) has caused great public concerns due to its recent large outbreaks and a close association with microcephaly in fetus and Guillain-Barre syndrome in adults. Rapid development of vaccines against ZIKV is a public health priority. To this end, we have constructed and purified recombinant ZIKV envelope protein using both prokaryotic and eukaryotic expression systems, and then tested their immunogenicity and protective efficacy in immune competent mice. Both protein immunogens elicited humoral and cellular immune responses, and protected immune competent mice from ZIKV challenge in vivo. These products could be further evaluated either as stand-alone vaccine candidate, or used in a prime-and-boost regimen with other forms of ZIKV vaccine. PMID:29590178

Immunization with a Borrelia burgdorferi BB0172-Derived Peptide Protects Mice against Lyme Disease

PubMed Central

Small, Christina M.; Ajithdoss, Dharani K.; Rodrigues Hoffmann, Aline; Mwangi, Waithaka; Esteve-Gassent, Maria D.

2014-01-01

Lyme disease is the most prevalent arthropod borne disease in the US and it is caused by the bacterial spirochete Borrelia burgdorferi (Bb), which is acquired through the bite of an infected Ixodes tick. Vaccine development efforts focused on the von Willebrand factor A domain of the borrelial protein BB0172 from which four peptides (A, B, C and D) were synthesized and conjugated to Keyhole Limpet Hemocyanin, formulated in Titer Max® adjuvant and used to immunize C3H/HeN mice subcutaneously at days 0, 14 and 21. Sera were collected to evaluate antibody responses and some mice were sacrificed for histopathology to evaluate vaccine safety. Twenty-eight days post-priming, protection was evaluated by needle inoculation of half the mice in each group with 103 Bb/mouse, whereas the rest were challenged with 105Bb/mouse. Eight weeks post-priming, another four groups of similarly immunized mice were challenged using infected ticks. In both experiments, twenty-one days post-challenge, the mice were sacrificed to determine antibody responses, bacterial burdens and conduct histopathology. Results showed that only mice immunized with peptide B were protected against challenge with Bb. In addition, compared to the other the treatment groups, peptide B-immunized mice showed very limited inflammation in the heart and joint tissues. Peptide B-specific antibody titers peaked at 8 weeks post-priming and surprisingly, the anti-peptide B antibodies did not cross-react with Bb lysates. These findings strongly suggest that peptide B is a promising candidate for the development of a new DIVA vaccine (Differentiate between Infected and Vaccinated Animals) for protection against Lyme disease. PMID:24505447

A single dose of a DNA vaccine encoding apa coencapsulated with 6,6'-trehalose dimycolate in microspheres confers long-term protection against tuberculosis in Mycobacterium bovis BCG-primed mice.

PubMed

Carlétti, Dyego; Morais da Fonseca, Denise; Gembre, Ana Flávia; Masson, Ana Paula; Weijenborg Campos, Lívia; Leite, Luciana C C; Rodrigues Pires, Andréa; Lannes-Vieira, Joseli; Lopes Silva, Célio; Bonato, Vânia Luiza Deperon; Horn, Cynthia

2013-08-01

Mycobacterium bovis BCG prime DNA (Mycobacterium tuberculosis genes)-booster vaccinations have been shown to induce greater protection against tuberculosis (TB) than BCG alone. This heterologous prime-boost strategy is perhaps the most realistic vaccination for the future of TB infection control, especially in countries where TB is endemic. Moreover, a prime-boost regimen using biodegradable microspheres seems to be a promising immunization to stimulate a long-lasting immune response. The alanine proline antigen (Apa) is a highly immunogenic glycoprotein secreted by M. tuberculosis. This study investigated the immune protection of Apa DNA vaccine against intratracheal M. tuberculosis challenge in mice on the basis of a heterologous prime-boost regimen. BALB/c mice were subcutaneously primed with BCG and intramuscularly boosted with a single dose of plasmid carrying apa and 6,6'-trehalose dimycolate (TDM) adjuvant, coencapsulated in microspheres (BCG-APA), and were evaluated 30 and 70 days after challenge. This prime-boost strategy (BCG-APA) resulted in a significant reduction in the bacterial load in the lungs, thus leading to better preservation of the lung parenchyma, 70 days postinfection compared to BCG vaccinated mice. The profound effect of this heterologous prime-boost regimen in the experimental model supports its development as a feasible strategy for prevention of TB.

Differential miRNA Expression in the Liver of Balb/c Mice Protected by Vaccination during Crisis of Plasmodium chabaudi Blood-Stage Malaria

PubMed Central

Dkhil, Mohamed A.; Al-Quraishy, Saleh A.; Abdel-Baki, Abdel-Azeem S.; Delic, Denis; Wunderlich, Frank

2017-01-01

MicroRNAs are increasingly recognized as epigenetic regulators for outcome of diverse infectious diseases and vaccination efficacy, but little information referring to this exists for malaria. This study investigates possible effects of both protective vaccination and P. chabaudi malaria on the miRNome of the liver as an effector against blood-stage malaria using miRNA microarrays and quantitative PCR. Plasmodium chabaudi blood-stage malaria takes a lethal outcome in female Balb/c mice, but a self-healing course after immunization with a non-infectious blood-stage vaccine. The liver robustly expresses 71 miRNA species at varying levels, among which 65 miRNA species respond to malaria evidenced as steadily increasing or decreasing expressions reaching highest or lowest levels toward the end of the crisis phase on day 11 p.i. in lethal malaria. Protective vaccination does not affect constitutive miRNA expression, but leads to significant (p < 0.05) changes in the expression of 41 miRNA species, however evidenced only during crisis. In vaccination-induced self-healing infections, 18 miRNA-species are up- and 14 miRNA-species are down-regulated by more than 50% during crisis in relation to non-vaccinated mice. Vaccination-induced self-healing and survival of otherwise lethal infections of P. chabaudi activate epigenetic miRNA-regulated remodeling processes in the liver manifesting themselves during crisis. Especially, liver regeneration is accelerated as suggested by upregulation of let-7a-5p, let-7b-5p, let-7c-5p, let-7d-5p, let-7f-5p, let-7g-5p, let-7i-5p, miR-26a, miR-122-5p, miR30a, miR27a, and mir-29a, whereas the up-regulated expression of miR-142-3p by more than 100% is compatible with the view of enhanced hepatic erythropoiesis, possibly at expense of megakaryopoiesis, during crisis of P. chabaudi blood-stage malaria. PMID:28123381

Immunological responses induced by a DNA vaccine expressing RON4 and by immunogenic recombinant protein RON4 failed to protect mice against chronic toxoplasmosis.

PubMed

Rashid, Imran; Hedhli, Dorsaf; Moiré, Nathalie; Pierre, Josette; Debierre-Grockiego, Françoise; Dimier-Poisson, Isabelle; Mévélec, Marie Noëlle

2011-11-08

The development of an effective vaccine against Toxoplasma gondii infection is an important issue due to the seriousness of the related public health problems, and the economic importance of this parasitic disease worldwide. Rhoptry neck proteins (RONs) are components of the moving junction macromolecular complex formed during invasion. The aim of this study was to evaluate the vaccine potential of RON4 using two vaccination strategies: DNA vaccination by the intramuscular route, and recombinant protein vaccination by the nasal route. We produced recombinant RON4 protein (RON4S2) using the Schneider insect cells expression system, and validated its antigenicity and immunogenicity. We also constructed optimized plasmids encoding full length RON4 (pRON4), or only the N-terminal (pNRON4), or the C-terminal part (pCRON4) of RON4. CBA/J mice immunized with pRON4, pNRON4 or pCRON4 plus a plasmid encoding the granulocyte-macrophage-colony-stimulating factor showed high IgG titers against rRON4S2. Mice immunized by the nasal route with rRON4S2 plus cholera toxin exhibited low levels of anti-RON4S2 IgG antibodies, and no intestinal IgA antibodies specific to RON4 were detected. Both DNA and protein vaccination generated a mixed Th1/Th2 response polarized towards the IgG1 antibody isotype. Both DNA and protein vaccination primed CD4+ T cells in vivo. In addition to the production of IFN-γ, and IL-2, Il-10 and IL-5 were also produced by the spleen cells of the immunized mice stimulated with RON4S2, suggesting that a mixed Th1/Th2 type immune response occurred in all the immunized groups. No cytokine was detectable in stimulated mesenteric lymph nodes from mice immunized by the nasal route. Immune responses were induced by both DNA and protein vaccination, but failed to protect the mice against a subsequent oral challenge with T. gondii cysts. In conclusion, strategies designed to enhance the immunogenicity and to redirect the cellular response towards a Th1 type response

DNA vaccines: protective immunizations by parenteral, mucosal, and gene-gun inoculations.

PubMed Central

Fynan, E F; Webster, R G; Fuller, D H; Haynes, J R; Santoro, J C; Robinson, H L

1993-01-01

Plasmid DNAs expressing influenza virus hemagglutinin glycoproteins have been tested for their ability to raise protective immunity against lethal influenza challenges of the same subtype. In trials using two inoculations of from 50 to 300 micrograms of purified DNA in saline, 67-95% of test mice and 25-63% of test chickens have been protected against a lethal influenza challenge. Parenteral routes of inoculation that achieved good protection included intramuscular and intravenous injections. Successful mucosal routes of vaccination included DNA drops administered to the nares or trachea. By far the most efficient DNA immunizations were achieved by using a gene gun to deliver DNA-coated gold beads to the epidermis. In mice, 95% protection was achieved by two immunizations with beads loaded with as little as 0.4 micrograms of DNA. The breadth of routes supporting successful DNA immunizations, coupled with the very small amounts of DNA required for gene-gun immunizations, highlight the potential of this remarkably simple technique for the development of subunit vaccines. Images Fig. 1 PMID:8265577

The intranasal vaccination of pregnant dams with Intimin and EspB confers protection in neonatal mice from Escherichia coli (EHEC) O157:H7 infection.

PubMed

Rabinovitz, B C; Larzábal, M; Vilte, D A; Cataldi, A; Mercado, E C

2016-05-27

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is responsible for intestinal disease and hemolytic uremic syndrome (HUS), a serious systemic complication which particularly affects children. In this study, we evaluated whether passive immunization protects from EHEC O157:H7 colonization and renal damage, by using a weaned BALB/c mouse model of infection. Recombinant proteins EspB and the carboxyl-terminal fragment of 280 amino acids of γ-intimin (γ-IntC280) were used in combination with a macrophage-activating lipopeptide-2 (MALP) adjuvant to immunize pregnant mice by the intranasal route. Neonatal mice were allowed to suckle vaccinated or sham-vaccinated dams until weaning when they were challenged by the oral route with a suspension of an E. coli O157:H7 Stx2+ strain. The excretion of the inoculated strain was followed for 72h. All vaccinated dams exhibited elevated serum IgG response against both γ-Int C280 and EspB. Passive immunization of newborn mice resulted in a significant increase in serum IgG titers against γ-Int C280 and a slight increase in EspB-specific antibodies. The neonates from vaccinated dams showed a significant reduction in EHEC O157:H7 colonization 48h post challenge. In addition, the level of plasma urea concentration, a marker of renal failure, was significantly higher in offsprings of sham-vaccinated mice. In conclusion, vaccination of pregnant dams with γ-Int C280 and EspB could reduce colonization and systemic toxicity of EHEC O157:H7 in their suckling offsprings. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthetic Long Peptide Influenza Vaccine Containing Conserved T and B Cell Epitopes Reduces Viral Load in Lungs of Mice and Ferrets

PubMed Central

Rosendahl Huber, S. K.; Camps, M. G. M.; Jacobi, R. H. J.; Mouthaan, J.; van Dijken, H.; van Beek, J.; Ossendorp, F.; de Jonge, J.

2015-01-01

Currently licensed influenza vaccines mainly induce antibodies against highly variable epitopes. Due to antigenic drift, protection is subtype or strain-specific and regular vaccine updates are required. In case of antigenic shifts, which have caused several pandemics in the past, completely new vaccines need to be developed. We set out to develop a vaccine that provides protection against a broad range of influenza viruses. Therefore, highly conserved parts of the influenza A virus (IAV) were selected of which we constructed antibody and T cell inducing peptide-based vaccines. The B epitope vaccine consists of the highly conserved HA2 fusion peptide and M2e peptide coupled to a CD4 helper epitope. The T epitope vaccine comprises 25 overlapping synthetic long peptides of 26-34 amino acids, thereby avoiding restriction for a certain MHC haplotype. These peptides are derived from nucleoprotein (NP), polymerase basic protein 1 (PB1) and matrix protein 1 (M1). C57BL/6 mice, BALB/c mice, and ferrets were vaccinated with the B epitopes, 25 SLP or a combination of both. Vaccine-specific antibodies were detected in sera of mice and ferrets and vaccine-specific cellular responses were measured in mice. Following challenge, both mice and ferrets showed a reduction of virus titers in the lungs in response to vaccination. Summarizing, a peptide-based vaccine directed against conserved parts of influenza virus containing B and T cell epitopes shows promising results for further development. Such a vaccine may reduce disease burden and virus transmission during pandemic outbreaks. PMID:26046664

Strain-specific protective immunity following vaccination against experimental Trypanosoma cruzi infection.

PubMed

Haolla, Filipe A; Claser, Carla; de Alencar, Bruna C G; Tzelepis, Fanny; de Vasconcelos, José Ronnie; de Oliveira, Gabriel; Silvério, Jaline C; Machado, Alexandre V; Lannes-Vieira, Joseli; Bruna-Romero, Oscar; Gazzinelli, Ricardo T; dos Santos, Ricardo Ribeiro; Soares, Milena B P; Rodrigues, Mauricio M

2009-09-18

Immunisation with Amastigote Surface Protein 2 (asp-2) and trans-sialidase (ts) genes induces protective immunity in highly susceptible A/Sn mice, against infection with parasites of the Y strain of Trypanosoma cruzi. Based on immunological and biological strain variations in T. cruzi parasites, our goal was to validate our vaccination results using different parasite strains. Due to the importance of the CD8(+) T cells in protective immunity, we initially determined which strains expressed the immunodominant H-2K(k)-restricted epitope TEWETGQI. We tested eight strains, four of which elicited immune responses to this epitope (Y, G, Colombian and Colombia). We selected the Colombian and Colombia strains for our studies. A/Sn mice were immunised with different regimens using both T. cruzi genes (asp-2 and ts) simultaneously and subsequently challenged with blood trypomastigotes. Immune responses before the challenge were confirmed by the presence of specific antibodies and peptide-specific T cells. Genetic vaccination did not confer protective immunity against acute infection with a lethal dose of the Colombian strain. In contrast, we observed a drastic reduction in parasitemia and a significant increase in survival, following challenge with an otherwise lethal dose of the Colombia strain. In many surviving animals with late-stage chronic infection, we observed alterations in the heart's electrical conductivity, compared to naive mice. In summary, we concluded that immunity against T. cruzi antigens, similar to viruses and bacteria, may be strain-specific and have a negative impact on vaccine development.

Protective efficacy of an inactivated Eurasian avian-like H1N1 swine influenza vaccine against homologous H1N1 and heterologous H1N1 and H1N2 viruses in mice.

PubMed

Sui, Jinyu; Yang, Dawei; Qiao, Chuanling; Xu, Huiyang; Xu, Bangfeng; Wu, Yunpu; Yang, Huanliang; Chen, Yan; Chen, Hualan

2016-07-19

Eurasian avian-like H1N1 (EA H1N1) swine influenza viruses are prevalent in pigs in Europe and Asia, but occasionally cause human infection, which raises concern about their pandemic potential. Here, we produced a whole-virus inactivated vaccine with an EA H1N1 strain (A/swine/Guangxi/18/2011, SW/GX/18/11) and evaluated its efficacy against homologous H1N1 and heterologous H1N1 and H1N2 influenza viruses in mice. A strong humoral immune response, which we measured by hemagglutination inhibition (HI) and virus neutralization (VN), was induced in the vaccine-inoculated mice upon challenge. The inactivated SW/GX/18/11 vaccine provided complete protection against challenge with homologous SW/GX/18/11 virus in mice and provided effective protection against challenge with heterologous H1N1 and H1N2 viruses with distinctive genomic combinations. Our findings suggest that this EA H1N1 vaccine can provide protection against both homologous H1N1 and heterologous H1N1 or H1N2 virus infection. As such, it is an excellent vaccine candidate to prevent H1N1 swine influenza. Copyright © 2016 Elsevier Ltd. All rights reserved.

Intranasal delivery of a protein subunit vaccine using a Tobacco Mosaic Virus platform protects against pneumonic plague.

PubMed

Arnaboldi, Paul M; Sambir, Mariya; D'Arco, Christina; Peters, Lauren A; Seegers, Jos F M L; Mayer, Lloyd; McCormick, Alison A; Dattwyler, Raymond J

2016-11-11

Yersinia pestis, one of history's deadliest pathogens, has killed millions over the course of human history. It has attributes that make it an ideal choice to produce mass casualties and is a prime candidate for use as a biological weapon. When aerosolized, Y. pestis causes pneumonic plague, a pneumonia that is 100% lethal if not promptly treated with effective antibiotics. Currently, there is no FDA approved plague vaccine. The current lead vaccine candidate, a parenterally administered protein subunit vaccine comprised of the Y. pestis virulence factors, F1 and LcrV, demonstrated variable levels of protection in primate pneumonic plague models. As the most likely mode of exposure in biological attack with Y. pestis is by aerosol, this raises a question of whether this parenteral vaccine will adequately protect humans against pneumonic plague. In the present study we evaluated two distinct mucosal delivery platforms for the intranasal (IN) administration of LcrV and F1 vaccine proteins, a live bacterial vector, Lactobacillus plantarum, and a Tobacco Mosaic Virus (TMV) based delivery platform. IN administration of L. plantarum expressing LcrV, or TMV-conjugated to LcrV and F1 (TMV-LcrV+TMV-F1) resulted in the similar induction of high titers of IgG antibodies and evidence of proinflammatory cytokine secretion. However, only the TMV-conjugate delivery platform protected against subsequent lethal challenge with Y. pestis. TMV-LcrV+TMV-F1 co-vaccinated mice had no discernable morbidity and no mortality, while mice vaccinated with L. plantarum expressing LcrV or rLcrV+rF1 without TMV succumbed to infection or were only partially protected. Thus, TMV is a suitable mucosal delivery platform for an F1-LcrV subunit vaccine that induces complete protection against pneumonic infection with a lethal dose of Y. pestis in mice. Copyright © 2016 Elsevier Ltd. All rights reserved.

TLR1/2 activation during heterologous prime-boost vaccination (DNA-MVA) enhances CD8+ T Cell responses providing protection against Leishmania (Viannia).

PubMed

Jayakumar, Asha; Castilho, Tiago M; Park, Esther; Goldsmith-Pestana, Karen; Blackwell, Jenefer M; McMahon-Pratt, Diane

2011-06-01

Leishmania (Viannia) parasites present particular challenges, as human and murine immune responses to infection are distinct from other Leishmania species, indicating a unique interaction with the host. Further, vaccination studies utilizing small animal models indicate that modalities and antigens that prevent infection by other Leishmania species are generally not protective. Using a newly developed mouse model of chronic L. (Viannia) panamensis infection and the heterologous DNA prime - modified vaccinia virus Ankara (MVA) boost vaccination modality, we examined whether the conserved vaccine candidate antigen tryparedoxin peroxidase (TRYP) could provide protection against infection/disease. Heterologous prime - boost (DNA/MVA) vaccination utilizing TRYP antigen can provide protection against disease caused by L. (V.) panamensis. However, protection is dependent on modulating the innate immune response using the TLR1/2 agonist Pam3CSK4 during DNA priming. Prime-boost vaccination using DNA alone fails to protect. Prior to infection protectively vaccinated mice exhibit augmented CD4 and CD8 IFNγ and memory responses as well as decreased IL-10 and IL-13 responses. IL-13 and IL-10 have been shown to be independently critical for disease in this model. CD8 T cells have an essential role in mediating host defense, as CD8 depletion reversed protection in the vaccinated mice; vaccinated mice depleted of CD4 T cells remained protected. Hence, vaccine-induced protection is dependent upon TLR1/2 activation instructing the generation of antigen specific CD8 cells and restricting IL-13 and IL-10 responses. Given the general effectiveness of prime-boost vaccination, the recalcitrance of Leishmania (Viannia) to vaccine approaches effective against other species of Leishmania is again evident. However, prime-boost vaccination modality can with modulation induce protective responses, indicating that the delivery system is critical. Moreover, these results suggest that CD8 T

Mucosal BCG Vaccination Induces Protective Lung-Resident Memory T Cell Populations against Tuberculosis

PubMed Central

Perdomo, Carolina; Zedler, Ulrike; Kühl, Anja A.; Lozza, Laura; Saikali, Philippe; Sander, Leif E.; Vogelzang, Alexis; Kupz, Andreas

2016-01-01

ABSTRACT Mycobacterium bovis Bacille Calmette-Guérin (BCG) is the only licensed vaccine against tuberculosis (TB), yet its moderate efficacy against pulmonary TB calls for improved vaccination strategies. Mucosal BCG vaccination generates superior protection against TB in animal models; however, the mechanisms of protection remain elusive. Tissue-resident memory T (TRM) cells have been implicated in protective immune responses against viral infections, but the role of TRM cells following mycobacterial infection is unknown. Using a mouse model of TB, we compared protection and lung cellular infiltrates of parenteral and mucosal BCG vaccination. Adoptive transfer and gene expression analyses of lung airway cells were performed to determine the protective capacities and phenotypes of different memory T cell subsets. In comparison to subcutaneous vaccination, intratracheal and intranasal BCG vaccination generated T effector memory and TRM cells in the lung, as defined by surface marker phenotype. Adoptive mucosal transfer of these airway-resident memory T cells into naive mice mediated protection against TB. Whereas airway-resident memory CD4+ T cells displayed a mixture of effector and regulatory phenotype, airway-resident memory CD8+ T cells displayed prototypical TRM features. Our data demonstrate a key role for mucosal vaccination-induced airway-resident T cells in the host defense against pulmonary TB. These results have direct implications for the design of refined vaccination strategies. PMID:27879332

Non-specific Effect of Vaccines: Immediate Protection against Respiratory Syncytial Virus Infection by a Live Attenuated Influenza Vaccine.

PubMed

Lee, Young J; Lee, Jeong Y; Jang, Yo H; Seo, Sang-Uk; Chang, Jun; Seong, Baik L

2018-01-01

The non-specific effects (NSEs) of vaccines have been discussed for their potential long-term beneficial effects beyond direct protection against a specific pathogen. Cold-adapted, live attenuated influenza vaccine (CAIV) induces local innate immune responses that provide a broad range of antiviral immunity. Herein, we examined whether X-31ca, a donor virus for CAIVs, provides non-specific cross-protection against respiratory syncytial virus (RSV). The degree of RSV replication was significantly reduced when X-31ca was administered before RSV infection without any RSV-specific antibody responses. The vaccination induced an immediate release of cytokines and infiltration of leukocytes into the respiratory tract, moderating the immune perturbation caused by RSV infection. The potency of protection against RSV challenge was significantly reduced in TLR3 -/- TLR7 -/- mice, confirming that the TLR3/7 signaling pathways are necessary for the observed immediate and short-term protection. The results suggest that CAIVs provide short-term, non-specific protection against genetically unrelated respiratory pathogens. The additional benefits of CAIVs in mitigating acute respiratory infections for which vaccines are not yet available need to be assessed in future studies.

A Single Dose of a DNA Vaccine Encoding Apa Coencapsulated with 6,6′-Trehalose Dimycolate in Microspheres Confers Long-Term Protection against Tuberculosis in Mycobacterium bovis BCG-Primed Mice

PubMed Central

Carlétti, Dyego; Morais da Fonseca, Denise; Gembre, Ana Flávia; Masson, Ana Paula; Weijenborg Campos, Lívia; Leite, Luciana C. C.; Rodrigues Pires, Andréa; Lannes-Vieira, Joseli; Lopes Silva, Célio; Bonato, Vânia Luiza Deperon

2013-01-01

Mycobacterium bovis BCG prime DNA (Mycobacterium tuberculosis genes)-booster vaccinations have been shown to induce greater protection against tuberculosis (TB) than BCG alone. This heterologous prime-boost strategy is perhaps the most realistic vaccination for the future of TB infection control, especially in countries where TB is endemic. Moreover, a prime-boost regimen using biodegradable microspheres seems to be a promising immunization to stimulate a long-lasting immune response. The alanine proline antigen (Apa) is a highly immunogenic glycoprotein secreted by M. tuberculosis. This study investigated the immune protection of Apa DNA vaccine against intratracheal M. tuberculosis challenge in mice on the basis of a heterologous prime-boost regimen. BALB/c mice were subcutaneously primed with BCG and intramuscularly boosted with a single dose of plasmid carrying apa and 6,6′-trehalose dimycolate (TDM) adjuvant, coencapsulated in microspheres (BCG-APA), and were evaluated 30 and 70 days after challenge. This prime-boost strategy (BCG-APA) resulted in a significant reduction in the bacterial load in the lungs, thus leading to better preservation of the lung parenchyma, 70 days postinfection compared to BCG vaccinated mice. The profound effect of this heterologous prime-boost regimen in the experimental model supports its development as a feasible strategy for prevention of TB. PMID:23740922

A whole-killed, blood-stage lysate vaccine protects against the malaria liver stage.

PubMed

Lu, X; Liu, T; Zhu, F; Chen, L; Xu, W

2017-01-01

Although the attenuated sporozoite is the most efficient vaccine to prevent infection with the malaria parasite, the limitation of a source of sterile sporozoites greatly hampers its application. In this study, we found that the whole-killed, blood-stage lysate vaccine could confer protection against the blood stage as well as the liver stage. Although the protective immunity induced by the whole-organism vaccine against the blood stage is dependent on parasite-specific CD4 + T-cell responses and antibodies, in mice immunized with the whole-killed, blood-stage lysate vaccine, CD8 + , but not CD4 + effector T-cell responses greatly contributed to protection against the liver stage. Thus, our data suggested that the whole-killed, blood-stage lysate vaccine could be an alternative promising strategy to prevent malaria infection and to reduce the morbidity and mortality of patients with malaria. © 2016 John Wiley & Sons Ltd.

Multiagent Vaccines Vectored by Venezuelan Equine Encephalitis Virus Replicon Elicits Immune Responses to Marburg Virus and Protection Against Anthrax and Botulinum Neurotoxin in Mice

DTIC Science & Technology

2006-01-01

and protection against anthrax and botulinum neurotoxin in mice John S. Lee a,∗, Jennifer L. Groebner a, Angela G. Hadjipanayis a,1, Diane L. Negley a...botulinum. Vaccine 24:6886 - 6892 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Lee, JS Groebner , JL Hadjipanayis

Siderophore vaccine conjugates protect against uropathogenic Escherichia coli urinary tract infection

PubMed Central

Mike, Laura A.; Smith, Sara N.; Sumner, Christopher A.; Eaton, Kathryn A.; Mobley, Harry L. T.

2016-01-01

Uropathogenic Escherichia coli (UPEC) is the primary cause of uncomplicated urinary tract infections (UTIs). Whereas most infections are isolated cases, 1 in 40 women experience recurrent UTIs. The rise in antibiotic resistance has complicated the management of chronic UTIs and necessitates new preventative strategies. Currently, no UTI vaccines are approved for use in the United States, and the development of a highly effective vaccine remains elusive. Here, we have pursued a strategy for eliciting protective immunity by vaccinating with small molecules required for pathogenesis, rather than proteins or peptides. Small iron-chelating molecules called siderophores were selected as antigens to vaccinate against UTI for this vaccine strategy. These pathogen-associated stealth siderophores evade host immune defenses and enhance bacterial virulence. Previous animal studies revealed that vaccination with siderophore receptor proteins protects against UTI. The poor solubility of these integral outer-membrane proteins in aqueous solutions limits their practical utility. Because their cognate siderophores are water soluble, we hypothesized that these bacterial-derived small molecules are prime vaccine candidates. To test this hypothesis, we immunized mice with siderophores conjugated to an immunogenic carrier protein. The siderophore–protein conjugates elicited an adaptive immune response that targeted bacterial stealth siderophores and protected against UTI. Our study has identified additional antigens suitable for a multicomponent UTI vaccine and highlights the potential use of bacterial-derived small molecules as antigens in vaccine therapies. PMID:27821778

Siderophore vaccine conjugates protect against uropathogenic Escherichia coli urinary tract infection.

PubMed

Mike, Laura A; Smith, Sara N; Sumner, Christopher A; Eaton, Kathryn A; Mobley, Harry L T

2016-11-22

Uropathogenic Escherichia coli (UPEC) is the primary cause of uncomplicated urinary tract infections (UTIs). Whereas most infections are isolated cases, 1 in 40 women experience recurrent UTIs. The rise in antibiotic resistance has complicated the management of chronic UTIs and necessitates new preventative strategies. Currently, no UTI vaccines are approved for use in the United States, and the development of a highly effective vaccine remains elusive. Here, we have pursued a strategy for eliciting protective immunity by vaccinating with small molecules required for pathogenesis, rather than proteins or peptides. Small iron-chelating molecules called siderophores were selected as antigens to vaccinate against UTI for this vaccine strategy. These pathogen-associated stealth siderophores evade host immune defenses and enhance bacterial virulence. Previous animal studies revealed that vaccination with siderophore receptor proteins protects against UTI. The poor solubility of these integral outer-membrane proteins in aqueous solutions limits their practical utility. Because their cognate siderophores are water soluble, we hypothesized that these bacterial-derived small molecules are prime vaccine candidates. To test this hypothesis, we immunized mice with siderophores conjugated to an immunogenic carrier protein. The siderophore-protein conjugates elicited an adaptive immune response that targeted bacterial stealth siderophores and protected against UTI. Our study has identified additional antigens suitable for a multicomponent UTI vaccine and highlights the potential use of bacterial-derived small molecules as antigens in vaccine therapies.

Protective immunity induced by an intranasal multivalent vaccine comprising 10 Lactococcus lactis strains expressing highly prevalent M-protein antigens derived from Group A Streptococcus.

PubMed

Wozniak, Aniela; Scioscia, Natalia; García, Patricia C; Dale, James B; Paillavil, Braulio A; Legarraga, Paulette; Salazar-Echegarai, Francisco J; Bueno, Susan M; Kalergis, Alexis M

2018-04-28

Streptococcus pyogenes (group A Streptococcus) causes diseases ranging from mild pharyngitis to severe invasive infections. The N-terminal fragment of Streptococcal M protein elicits protective antibodies and is an attractive vaccine target. However, this N- terminal fragment is hypervariable and there are more than 200 different M types. We are developing an intranasal live bacterial vaccine comprised of 10 strains of Lactococcus lactis, each expressing one N-terminal fagment of M protein. Live bacterial-vectored vaccines have lower associated costs because of its less complex manufacturing processes compared to protein subunit vaccines. Moreover, intranasal administration does not require syringe or specilized personnel. The evaluation of individual vaccine types (M1, M2, M3, M4, M6, M9, M12, M22, M28 and M77) showed that most of them protected mice against challenge with virulent S. pyogenes. All of the 10 strains combined in a 10-valent vaccine (Mx10) induced serum and bronchoalveolar lavages IgG titers that ranged from 3 to 10-fold those of unimmunized mice. Survival of Mx10-immunized mice after intranasal challenge with M28 streptococci is significantly higher than unimmunized mice. In contrast, when mice were challenged with M75 streptococci, survival of Mx10-immunized mice was not significantly different from unimmunized mice. Mx-10 immunized mice were significantly less colonized with S. pyogenes in oropharyngeal washes and developed less severe disease symptoms after challenge compared to unimmunized mice. Our L. lactis-based vaccine may provide an alternative solution to the development of broadly protective group A streptococcal vaccines. © 2018 The Societies and John Wiley & Sons Australia, Ltd.

Protective vaccination and blood-stage malaria modify DNA methylation of gene promoters in the liver of Balb/c mice.

PubMed

Al-Quraishy, Saleh; Dkhil, Mohamed A; Abdel-Baki, Abdel-Azeem S; Ghanjati, Foued; Erichsen, Lars; Santourlidis, Simeon; Wunderlich, Frank; Araúzo-Bravo, Marcos J

2017-05-01

Epigenetic mechanisms such as DNA methylation are increasingly recognized to be critical for vaccination efficacy and outcome of different infectious diseases, but corresponding information is scarcely available for host defense against malaria. In the experimental blood-stage malaria Plasmodium chabaudi, we investigate the possible effects of a blood-stage vaccine on DNA methylation of gene promoters in the liver, known as effector against blood-stage malaria, using DNA methylation microarrays. Naturally susceptible Balb/c mice acquire, by protective vaccination, the potency to survive P. chabaudi malaria and, concomitantly, modifications of constitutive DNA methylation of promoters of numerous genes in the liver; specifically, promoters of 256 genes are hyper(=up)- and 345 genes are hypo(=down)-methylated (p < 0.05). Protective vaccination also leads to changes in promoter DNA methylation upon challenge with P. chabaudi at peak parasitemia on day 8 post infection (p.i.), when 571 and 1013 gene promoters are up- and down-methylated, respectively, in relation to constitutive DNA methylation (p < 0.05). Gene set enrichment analyses reveal that both vaccination and P. chabaudi infections mainly modify promoters of those genes which are most statistically enriched with functions relating to regulation of transcription. Genes with down-methylated promoters encompass those encoding CX3CL1, GP130, and GATA2, known to be involved in monocyte recruitment, IL-6 trans-signaling, and onset of erythropoiesis, respectively. Our data suggest that vaccination may epigenetically improve parts of several effector functions of the liver against blood-stage malaria, as, e.g., recruitment of monocyte/macrophage to the liver accelerated liver regeneration and extramedullary hepatic erythropoiesis, thus leading to self-healing of otherwise lethal P. chabaudi blood-stage malaria.

A Yersinia pestis lpxM-mutant live vaccine induces enhanced immunity against bubonic plague in mice and guinea pigs.

PubMed

Feodorova, V A; Pan'kina, L N; Savostina, E P; Sayapina, L V; Motin, V L; Dentovskaya, S V; Shaikhutdinova, R Z; Ivanov, S A; Lindner, B; Kondakova, A N; Bystrova, O V; Kocharova, N A; Senchenkova, S N; Holst, O; Pier, G B; Knirel, Y A; Anisimov, A P

2007-11-01

The lpxM mutant of the live vaccine Yersinia pestis EV NIIEG strain synthesising a less toxic penta-acylated lipopolysaccharide was found to be avirulent in mice and guinea pigs, notably showing no measurable virulence in Balb/c mice which do retain some susceptibility to the parental strain itself. Twenty-one days after a single injection of the lpxM-mutant, 85-100% protection was achieved in outbred mice and guinea pigs, whereas a 43% protection rate was achieved in Balb/c mice given single low doses (10(3) to 2.5 x 10(4) CFU) of this vaccine. A subcutaneous challenge with 2000 median lethal doses (equal to 20,000 CFU) of fully virulent Y. pestis 231 strain, is a 6-10-fold higher dose than that which the EV NIIEG itself can protect against.

Coinjection of a vaccine and anti-viral agents can provide fast-acting protection from foot-and-mouth disease.

PubMed

You, Su-Hwa; Kim, Taeseong; Choi, Joo-Hyung; Park, Gundo; Lee, Kwang-Nyeong; Kim, Byounghan; Lee, Myoung-Heon; Kim, Hyun-Soo; Kim, Su-Mi; Park, Jong-Hyeon

2017-07-01

Foot-and-mouth disease (FMD) is the cause of an economically devastating animal disease. With commercial inactivated FMD vaccines, the protection against FMD virus (FMDV) begins a minimum of 4 days post vaccination (dpv). Therefore, antiviral agents could be proposed for rapid protection and to reduce the spread of FMDV during outbreaks until vaccine-induced protective immunity occurs. In previous studies, we have developed two recombinant adenoviruses that simultaneously express porcine interferon-α and interferon-γ (Ad-porcine IFN-αγ) and multiple siRNAs that target the non-structural protein-regions of FMDV (Ad-3siRNA), and we have shown that the combination of the two antiviral agents (referred to here as Ad combination) induced robust protection against FMDV in pigs. In an attempt to provide complete protection against FMDV, we co-administered Ad combination and the FMD vaccine to mice and pigs. In the C57BL/6 mice model, we observed rapid and continuous protection against homologous FMDV challenge from 1 to 3 dpv-the period in which vaccine-mediated immunity is absent. In the pig experiments, we found that most of the pigs (five out of six) that received vaccine + Ad combination and were challenged with FMDV at 1 or 2 dpv were clinically protected from FMDV. In addition, most of the pigs that received vaccine + Ad combination and all pigs inoculated with the vaccine only were clinically protected from an FMDV challenge at 7 dpv. We believe that the antiviral agent ensures early protection from FMDV, and the vaccine participates in protection after 7 dpv. Therefore, we can say that the combination of the FMD vaccine and effective antiviral agents may offer both fast-acting and continuous protection against FMDV. In further studies, we plan to design coadministration of Ad combination and novel vaccines. Copyright © 2017 Elsevier B.V. All rights reserved.

Prime-boost BCG vaccination with DNA vaccines based in β-defensin-2 and mycobacterial antigens ESAT6 or Ag85B improve protection in a tuberculosis experimental model

PubMed Central

Cervantes-Villagrana, Alberto R.; Hernández-Pando, Rogelio; Biragyn, Arya; Castañeda-Delgado, Julio; Bodogai, Monica; Martínez-Fierro, Margarita; Sada, Eduardo; Trujillo, Valentin; Enciso-Moreno, Antonio; Rivas-Santiago, Bruno

2018-01-01

The World Health Organization (WHO) has estimated that there are about 8 million new cases annually of active Tuberculosis (TB). Despite its irregular effectiveness (0–89%), the Bacillus Calmette-Guérin) BCG is the only vaccine available worldwide for prevention of TB; thus, the design is important of novel and more efficient vaccination strategies. Considering that β-defensin-2 is an antimicrobial peptide that induces dendritic cell maturation through the TLR-4 receptor and that both ESAT-6 and Ag85B are immunodominant mycobacterial antigens and efficient activators of the protective immune response, we constructed two DNA vaccines by the fusion of the gene encoding β-defensin-2 and antigens ESAT6 (pDE) and 85B (pDA). After confirming efficient local antigen expression that induced high and stable Interferon gamma (IFN-γ) production in intramuscular (i.m.) vaccinated Balb/c mice, groups of mice were vaccinated with DNA vaccines in a prime-boost regimen with BCG and with BCG alone, and 2 months later were challenged with the mild virulence reference strain H37Rv and the highly virulent clinical isolate LAM 5186. The level of protection was evaluated by survival, lung bacilli burdens, and extension of tissue damage (pneumonia). Vaccination with both DNA vaccines showed similar protection to that of BCG. After the challenge with the highly virulent Mycobacterium tuberculosis strain, animals that were prime-boosted with BCG and then boosted with both DNA vaccines showed significant higher survival and less tissue damage than mice vaccinated only with BCG. These results suggest that improvement of BCG vaccination, such as the prime-boost DNA vaccine, represents a more efficient vaccination scheme against TB. PMID:23196205

Prime-boost BCG vaccination with DNA vaccines based in β-defensin-2 and mycobacterial antigens ESAT6 or Ag85B improve protection in a tuberculosis experimental model.

PubMed

Cervantes-Villagrana, Alberto R; Hernández-Pando, Rogelio; Biragyn, Arya; Castañeda-Delgado, Julio; Bodogai, Monica; Martínez-Fierro, Margarita; Sada, Eduardo; Trujillo, Valentin; Enciso-Moreno, Antonio; Rivas-Santiago, Bruno

2013-01-11

The World Health Organization (WHO) has estimated that there are about 8 million new cases annually of active Tuberculosis (TB). Despite its irregular effectiveness (0-89%), the Bacillus Calmette-Guérin) BCG is the only vaccine available worldwide for prevention of TB; thus, the design is important of novel and more efficient vaccination strategies. Considering that β-defensin-2 is an antimicrobial peptide that induces dendritic cell maturation through the TLR-4 receptor and that both ESAT-6 and Ag85B are immunodominant mycobacterial antigens and efficient activators of the protective immune response, we constructed two DNA vaccines by the fusion of the gene encoding β-defensin-2 and antigens ESAT6 (pDE) and 85B (pDA). After confirming efficient local antigen expression that induced high and stable Interferon gamma (IFN-γ) production in intramuscular (i.m.) vaccinated Balb/c mice, groups of mice were vaccinated with DNA vaccines in a prime-boost regimen with BCG and with BCG alone, and 2 months later were challenged with the mild virulence reference strain H37Rv and the highly virulent clinical isolate LAM 5186. The level of protection was evaluated by survival, lung bacilli burdens, and extension of tissue damage (pneumonia). Vaccination with both DNA vaccines showed similar protection to that of BCG. After the challenge with the highly virulent Mycobacterium tuberculosis strain, animals that were prime-boosted with BCG and then boosted with both DNA vaccines showed significant higher survival and less tissue damage than mice vaccinated only with BCG. These results suggest that improvement of BCG vaccination, such as the prime-boost DNA vaccine, represents a more efficient vaccination scheme against TB. Copyright © 2012 Elsevier Ltd. All rights reserved.

Vaccination with Leishmania histone H1-pulsed dendritic cells confers protection in murine visceral leishmaniasis.

PubMed

Agallou, Maria; Smirlis, Despina; Soteriadou, Ketty P; Karagouni, Evdokia

2012-07-20

Visceral leishmaniasis is the most severe form of leishmaniases affecting millions of people worldwide often resulting in death despite optimal therapy. Thus, there is an urgent need for the development of effective anti-infective vaccine(s). In the present study, we evaluated the prophylactic value of bone marrow-derived dendritic cells (BM-DCs) pulsed with the Leishmania (L.) infantum histone H1. We developed fully mature BM-DCs characterized by enhanced capacity of IL-12 production after ex vivo pulsing with GST-LeishH1. Intravenous administration of these BM-DCs in naive BALB/c mice resulted in antigen-specific spleenocyte proliferation and IgG1 isotype antibody production and conferred protection against experimental challenge with L. infantum independently of CpG oligonucleotides (ODNs) co-administration. Protection was associated with a pronounced enhancement of parasite-specific IFNγ-producing cells and reduction of cells producing IL-10, whereas IL-4 production was comparable in protected and non-protected mice. The polarization of immune responses to Th1 type was further confirmed by the elevation of parasite-specific IgG2a/IgG1 ratio in protected mice. The above data indicate the immunostimulatory capacity of Leishmania histone H1 and further support its exploitation as a candidate protein for vaccine development against leishmaniasis. Copyright © 2012 Elsevier Ltd. All rights reserved.

Immunogenicity and efficacy of a chimpanzee adenovirus-vectored Rift Valley fever vaccine in mice.

PubMed

Warimwe, George M; Lorenzo, Gema; Lopez-Gil, Elena; Reyes-Sandoval, Arturo; Cottingham, Matthew G; Spencer, Alexandra J; Collins, Katharine A; Dicks, Matthew D J; Milicic, Anita; Lall, Amar; Furze, Julie; Turner, Alison V; Hill, Adrian V S; Brun, Alejandro; Gilbert, Sarah C

2013-12-05

Rift Valley Fever (RVF) is a viral zoonosis that historically affects livestock production and human health in sub-Saharan Africa, though epizootics have also occurred in the Arabian Peninsula. Whilst an effective live-attenuated vaccine is available for livestock, there is currently no licensed human RVF vaccine. Replication-deficient chimpanzee adenovirus (ChAd) vectors are an ideal platform for development of a human RVF vaccine, given the low prevalence of neutralizing antibodies against them in the human population, and their excellent safety and immunogenicity profile in human clinical trials of vaccines against a wide range of pathogens. Here, in BALB/c mice, we evaluated the immunogenicity and efficacy of a replication-deficient chimpanzee adenovirus vector, ChAdOx1, encoding the RVF virus envelope glycoproteins, Gn and Gc, which are targets of virus neutralizing antibodies. The ChAdOx1-GnGc vaccine was assessed in comparison to a replication-deficient human adenovirus type 5 vector encoding Gn and Gc (HAdV5-GnGc), a strategy previously shown to confer protective immunity against RVF in mice. A single immunization with either of the vaccines conferred protection against RVF virus challenge eight weeks post-immunization. Both vaccines elicited RVF virus neutralizing antibody and a robust CD8+ T cell response. Together the results support further development of RVF vaccines based on replication-deficient adenovirus vectors, with ChAdOx1-GnGc being a potential candidate for use in future human clinical trials.

Immunogenicity, protective efficacy and mechanism of novel CCS adjuvanted influenza vaccine.

PubMed

Even-Or, Orli; Samira, Sarit; Rochlin, Eli; Balasingam, Shobana; Mann, Alex J; Lambkin-Williams, Rob; Spira, Jack; Goldwaser, Itzhak; Ellis, Ronald; Barenholz, Yechezkel

2010-09-07

We optimized the immunogenicity of adjuvanted seasonal influenza vaccine based on commercial split influenza virus as an antigen (hemagglutinin = HA) and on a novel polycationic liposome as a potent adjuvant and efficient antigen carrier (CCS/C-HA vaccine). The vaccine was characterized physicochemically, and the mechanism of action of CCS/C as antigen carrier and adjuvant was studied. The optimized CCS/C-HA split virus vaccine, when administered intramuscularly (i.m.), is significantly more immunogenic in mice, rats and ferrets than split virus HA vaccine alone, and it provides for protective immunity in ferrets and mice against live virus challenge that exceeds the degree of efficacy of the split virus vaccine. Similar adjuvant effects of optimized CCS/C are also observed in mice for H1N1 swine influenza antigen. The CCS/C-HA vaccine enhances immune responses via the Th1 and Th2 pathways, and it increases both the humoral responses and the production of IL-2 and IFN-γ but not of the pro-inflammatory factor TNFα. In mice, levels of CD4(+) and CD8(+) T-cells and of MHC II and CD40 co-stimulatory molecules are also elevated. Structure-function relationship studies of the CCS molecule as an adjuvant/carrier show that replacing the saturated palmitoyl acyl chain with the mono-unsaturated oleoyl (C18:1) chain affects neither size distribution and zeta potential nor immune responses in mice. However, replacing the polyalkylamine head group spermine (having two secondary amines) with spermidine (having only one secondary amine) reduces the enhancement of the immune response by ∼ 50%, while polyalkylamines by themselves are ineffective in improving the immunogenicity over the commercial HA vaccine. This highlights the importance of the particulate nature of the carrier and the polyalkylamine secondary amines in the enhancement of the immune responses against seasonal influenza. Altogether, our results suggest that the CCS/C polycationic liposomes combine the

Efficacy of intranasal LaAg vaccine against Leishmania amazonensis infection in partially resistant C57Bl/6 mice.

PubMed

Pratti, Juliana Elena Silveira; Ramos, Tadeu Diniz; Pereira, Joyce Carvalho; da Fonseca-Martins, Alessandra Marcia; Maciel-Oliveira, Diogo; Oliveira-Silva, Gabriel; de Mello, Mirian França; Chaves, Suzana Passos; Gomes, Daniel Claudio Oliveira; Diaz, Bruno Lourenço; Rossi-Bergmann, Bartira; de Matos Guedes, Herbert Leonel

2016-10-06

We have previously demonstrated that intranasal vaccination of highly susceptible BALB/c mice with whole Leishmania amazonensis antigens (LaAg) leads to protection against murine cutaneous leishmaniasis. Here, we evaluate the response of partially resistant C57BL/6 mice to vaccination as a more representative experimental model of human cutaneous leishmaniasis. C57BL/6 mice from different animal facilities were infected with L. amazonensis (Josefa strain) to establish the profile of infection. Intranasal vaccination was performed before the infection challenge with two doses of 10 μg of LaAg alone or associated with the adjuvant ADDAVAX® by instillation in the nostrils. The lesion progression was measured with a dial caliper and the parasite load by limited dilution assay in the acute and chronic phases of infection. Cytokines were quantified by ELISA in the homogenates of infected footpads. C57BL/6 mice from different animal facilities presented the same L. amazonensis infection profile, displaying a progressive acute phase followed by a controlled chronic phase. Parasites cultured in M199 and Schneider's media were equally infective. Intranasal vaccination with LaAg led to milder acute and chronic phases of the disease. The mechanism of protection was associated with increased production of IFN-gamma in the infected tissue as measured in the acute phase. Association with the ADDAVAX® adjuvant did not improve the efficacy of intranasal LaAg vaccination. Rather, ADDAVAX® reduced vaccination efficacy. This study demonstrates that the efficacy of adjuvant-free intranasal vaccination with LaAg is extendable to the more resistant C57Bl/6 mouse model of infection with L. amazonensis, and is thus not exclusive to the susceptible BALB/c model. These results imply that mucosal immunomodulation by LaAg leads to peripheral protection irrespective of the genetic background of the host.

A dual purpose universal influenza vaccine candidate confers protective immunity against anthrax.

PubMed

Arévalo, Maria T; Li, Junwei; Diaz-Arévalo, Diana; Chen, Yanping; Navarro, Ashley; Wu, Lihong; Yan, Yongyong; Zeng, Mingtao

2017-03-01

Preventive influenza vaccines must be reformulated annually because of antigen shift and drift of circulating influenza viral strains. However, seasonal vaccines do not always match the circulating strains, and there is the ever-present threat that avian influenza viruses may adapt to humans. Hence, a universal influenza vaccine is needed to provide protective immunity against a broad range of influenza viruses. We designed an influenza antigen consisting of three tandem M2e repeats plus HA2, in combination with a detoxified anthrax oedema toxin delivery system (EFn plus PA) to enhance immune responses. The EFn-3×M2e-HA2 plus PA vaccine formulation elicited robust, antigen-specific, IgG responses; and was protective against heterologous influenza viral challenge when intranasally delivered to mice three times. Moreover, use of the detoxified anthrax toxin system as an adjuvant had the additional benefit of generating protective immunity against anthrax. Hence, this novel vaccine strategy could potentially address two major emerging public health and biodefence threats. © 2016 John Wiley & Sons Ltd.

[Study on construction and immune protective effect of recombinant nucleic acid vaccine of Toxoplasma gondii].

PubMed

Wei, Qing-Kuan

2012-04-01

To construct the polyvalent recombinant nucleic acid vaccine of Toxoplasma gondii and measure its protective immune effect. The gene of heat shock protein (HSP70) was amplified by PCR and inserted into the recombinant plasmid of pcDNA3-ROP2-p30 to construct recombinant polyvalent nucleic vaccine (pcDNA3-ROP2-p30-Hsp70). BALB/c mice were immunized with the constructed recombinant nucleic vaccine. CD4+ and CD8+ in the splenic lymphocytes and the lymphocytes in anticoagulant whole blood, the immune indices such as antibodies (IgG, IgM and IgA) and IFN-gamma, TNF, IL-2, IL-4, IL-12 in serum and splenic lymphocytes culture medium were detected, along with the challenge experiment. The protective immune responses that caused by the vaccine was measured by detecting the changes of immune indices of mice and the challenge experiment. 916 bp fragment of HSP70 gene was amplified by PCR. The recombinant polyvalent nucleic vaccine pcDNA3-ROP2-p30-HSP70 that included the whole open reading frame sequence of HSP gene was successfully constructed. The immunization results also showed this polyvalent nucleic vaccine could induce strong cellular and humoral responses by the detection of higher antibody titer in the experimental mice group, the increasing proliferation of CD4+ and CD8+ cells with significant deviations among the groups (F(CD4+) = 45.00, F(CD8+) = 15.01, all P < 0.01) and the apparent up-regulated levels of several cytokines IFN-gamma, IL-2 and IL-12 in serum and cultural supernatant of spleen cells, with more striking effect in serum. As a result of the challenge experiment, the immunized mice showed a longer survival time. The recombinant nucleic acid vaccine pcDNA3-ROP2-p30-HSP70 possesses a strong immunogenicity and is able to induce an immune protection.

A Bivalent Heterologous DNA Virus-Like-Particle Prime-Boost Vaccine Elicits Broad Protection against both Group 1 and 2 Influenza A Viruses

PubMed Central

Jiang, Wenbo; Wang, Shuangshuang; Chen, Honglin; Ren, Huanhuan; Huang, Xun; Wang, Guiqin; Chen, Ling; Chen, Zhiwei

2017-01-01

ABSTRACT Current seasonal influenza vaccines are efficacious when vaccine strains are matched with circulating strains. However, they do not protect antigenic variants and newly emerging pandemic and outbreak strains. Thus, there is a critical need for developing so-called “universal” vaccines that protect against all influenza viruses. In the present study, we developed a bivalent heterologous DNA virus-like particle prime-boost vaccine strategy. We show that mice immunized with this vaccine were broadly protected against lethal challenge from group 1 (H1, H5, and H9) and group 2 (H3 and H7) viruses, with 94% aggregate survival. To determine the immune correlates of protection, we performed passive immunizations and in vitro assays. We show that this vaccine elicited antibody responses that bound HA from group 1 (H1, H2, H5, H6, H8, H9, H11, and H12) and group 2 (H3, H4, H7, H10, H14, and H15) and neutralized homologous and intrasubtypic H5 and H7 and heterosubtypic H1 viruses and hemagglutinin-specific CD4 and CD8 T cell responses. As a result, passive immunization with immune sera fully protected mice against H5, H7, and H1 challenge, whereas with both immune sera and T cells the mice survived heterosubtypic H3 and H9 challenge. Thus, it appears that (i) neutralizing antibodies alone fully protect against homologous and intrasubtypic H5 and H7 and (ii) neutralizing and binding antibodies are sufficient to protect against heterosubtypic H1, (iii) but against heterosubtypic H3 and H9, binding antibodies and T cells are required for complete survival. We believe that this vaccine regimen could potentially be a candidate for a “universal” influenza vaccine. IMPORTANCE Influenza virus infection is global health problem. Current seasonal influenza vaccines are efficacious only when vaccine strains are matched with circulating strains. However, these vaccines do not protect antigenic variants and newly emerging pandemic and outbreak strains. Because of this

Mucosal BCG Vaccination Induces Protective Lung-Resident Memory T Cell Populations against Tuberculosis.

PubMed

Perdomo, Carolina; Zedler, Ulrike; Kühl, Anja A; Lozza, Laura; Saikali, Philippe; Sander, Leif E; Vogelzang, Alexis; Kaufmann, Stefan H E; Kupz, Andreas

2016-11-22

Mycobacterium bovis Bacille Calmette-Guérin (BCG) is the only licensed vaccine against tuberculosis (TB), yet its moderate efficacy against pulmonary TB calls for improved vaccination strategies. Mucosal BCG vaccination generates superior protection against TB in animal models; however, the mechanisms of protection remain elusive. Tissue-resident memory T (T RM ) cells have been implicated in protective immune responses against viral infections, but the role of T RM cells following mycobacterial infection is unknown. Using a mouse model of TB, we compared protection and lung cellular infiltrates of parenteral and mucosal BCG vaccination. Adoptive transfer and gene expression analyses of lung airway cells were performed to determine the protective capacities and phenotypes of different memory T cell subsets. In comparison to subcutaneous vaccination, intratracheal and intranasal BCG vaccination generated T effector memory and T RM cells in the lung, as defined by surface marker phenotype. Adoptive mucosal transfer of these airway-resident memory T cells into naive mice mediated protection against TB. Whereas airway-resident memory CD4 + T cells displayed a mixture of effector and regulatory phenotype, airway-resident memory CD8 + T cells displayed prototypical T RM features. Our data demonstrate a key role for mucosal vaccination-induced airway-resident T cells in the host defense against pulmonary TB. These results have direct implications for the design of refined vaccination strategies. BCG remains the only licensed vaccine against TB. Parenterally administered BCG has variable efficacy against pulmonary TB, and thus, improved prevention strategies and a more refined understanding of correlates of vaccine protection are required. Induction of memory T cells has been shown to be essential for protective TB vaccines. Mimicking the natural infection route by mucosal vaccination has been known to generate superior protection against TB in animal models; however, the

Inter-Clade Protection Offered by Mw-Adjuvanted Recombinant HA, NP Proteins, and M2e Peptide Combination Vaccine in Mice Correlates with Cellular Immune Response.

PubMed

Ingle, Nilesh B; Virkar, Rashmi G; Arankalle, Vidya A

2016-01-01

We documented earlier that Mw (heat-killed suspension of Mycobacterium indicus pranii ) adjuvant when used with conserved antigens, nucleoprotein (NP), and ectodomain of matrix (M2) protein (M2e) provided complete protection against homologous (clade 2.2) virus challenge in mice. The present study extends these observations to inter-clade challenge (clade 2.3.2.1) H5N1 virus and attempts to understand preliminary immunologic basis for the observed protection. Female BALB/c mice immunized with a single or two doses of vaccine formulations (clade 2.2 antigens) were challenged with 100LD50 homologous or heterologous (clade 2.3.2.1) virus. To understand the preliminary immunologic mechanism, we studied proportions of selected immune cell types, immune response gene expression, and Th1/Th2 cytokines induced by antigen-stimulated splenocytes from immunized mice, at different time points. Complete protection was conferred by Mw-HA, Mw-HA + NP, and Mw-HA + NP + M2e against homologous challenge. The protection correlated with IgG2a antibody titers indicating important role of Th1 response. Despite high inter-cladal antigenic differences, complete protection against the heterologous strain was achieved with Mw-HA + NP + M2e. Of note, a single dose with higher antigen concentrations (50 µg HA + 50 μg NP + 50 μg M2e) led to 80% protection against clade 2.3.2.1 strain. The protection conferred by Mw-HNM correlated with induction of IFN-γ, CD8 + T cytotoxic cells, and CD4 + T helper cells. Mw-adjuvanted HA + NP + M2e combination represents a promising vaccine candidate deserving further evaluation.

Activity in mice of recombinant BCG-EgG1Y162 vaccine for Echinococcus granulosus infection.

PubMed

Ma, Xiumin; Zhao, Hui; Zhang, Fengbo; Zhu, Yuejie; Peng, Shanshan; Ma, Haimei; Cao, Chunbao; Xin, Yan; Yimiti, Delixiati; Wen, Hao; Ding, Jianbing

2016-01-01

Cystic hydatid disease is a zoonotic parasitic disease caused by Echinococcus granulosus which is distributed worldwide. The disease is difficult to treat with surgery removal is the only cure treatment. In the high endemic areas, vaccination of humans is believed a way to protect communities from the disease. In this study we vaccinated BALB/c mice with rBCG-EgG1Y162, and then detected the level of IgG and IgE specifically against the recombinant protein by ELISA, rBCG-EgG1Y162 induced strong and specific cellular and humoral immune responses. In vitro study showed that rBCG-EgG1Y162 vaccine not only promote splenocytes proliferation but also active T cell. In addition, the rBCG-EgG1Y162 induced a protection in the mice against secondary infection of Echinococcus granulosus.

Protection against Experimental Cryptococcosis following Vaccination with Glucan Particles Containing Cryptococcus Alkaline Extracts

PubMed Central

Lee, Chrono K.; Huang, Haibin; Shen, Zu T.; Lodge, Jennifer K.; Leszyk, John; Ostroff, Gary R.

2015-01-01

ABSTRACT A vaccine capable of protecting at-risk persons against infections due to Cryptococcus neoformans and Cryptococcus gattii could reduce the substantial global burden of human cryptococcosis. Vaccine development has been hampered though, by lack of knowledge as to which antigens are immunoprotective and the need for an effective vaccine delivery system. We made alkaline extracts from mutant cryptococcal strains that lacked capsule or chitosan. The extracts were then packaged into glucan particles (GPs), which are purified Saccharomyces cerevisiae cell walls composed primarily of β-1,3-glucans. Subcutaneous vaccination with the GP-based vaccines provided significant protection against subsequent pulmonary infection with highly virulent strains of C. neoformans and C. gattii. The alkaline extract derived from the acapsular strain was analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS), and the most abundant proteins were identified. Separation of the alkaline extract by size exclusion chromatography revealed fractions that conferred protection when loaded in GP-based vaccines. Robust Th1- and Th17-biased CD4+ T cell recall responses were observed in the lungs of vaccinated and infected mice. Thus, our preclinical studies have indicated promising cryptococcal vaccine candidates in alkaline extracts delivered in GPs. Ongoing studies are directed at identifying the individual components of the extracts that confer protection and thus would be promising candidates for a human vaccine. PMID:26695631

Protection of mice deficient in mature B cells from West Nile virus infection by passive and active immunization

PubMed Central

Draves, Kevin E.; Young, Lucy B.; Bryan, Marianne A.; Dresch, Christiane; Diamond, Michael S.; Gale, Michael

2017-01-01

B cell activating factor receptor (BAFFR)-/- mice have a profound reduction in mature B cells, but unlike μMT mice, they have normal numbers of newly formed, immature B cells. Using a West Nile virus (WNV) challenge model that requires antibodies (Abs) for protection, we found that unlike wild-type (WT) mice, BAFFR-/- mice were highly susceptible to WNV and succumbed to infection within 8 to 12 days after subcutaneous virus challenge. Although mature B cells were required to protect against lethal infection, infected BAFFR-/- mice had reduced WNV E-specific IgG responses and neutralizing Abs. Passive transfer of immune sera from previously infected WT mice rescued BAFFR-/- and fully B cell-deficient μMT mice, but unlike μMT mice that died around 30 days post-infection, BAFFR-/- mice survived, developed WNV-specific IgG Abs and overcame a second WNV challenge. Remarkably, protective immunity could be induced in mature B cell-deficient mice. Administration of a WNV E-anti-CD180 conjugate vaccine 30 days prior to WNV infection induced Ab responses that protected against lethal infection in BAFFR-/- mice but not in μMT mice. Thus, the immature B cells present in BAFFR-/- and not μMT mice contribute to protective antiviral immunity. A CD180-based vaccine may promote immunity in immunocompromised individuals. PMID:29176765

Vaccination with recombinant L7/L12-truncated Omp31 protein induces protection against Brucella infection in BALB/c mice.

PubMed

Golshani, Maryam; Rafati, Sima; Dashti, Amir; Gholami, Elham; Siadat, Seyed Davar; Oloomi, Mana; Jafari, Anis; Bouzari, Saeid

2015-06-01

Brucellosis is the most common bacterial zoonotic disease worldwide and no vaccine is available for the prevention of human brucellosis. In humans, brucellosis is mostly caused by Brucella melitensis and Brucella abortus. The Outer membrane protein 31 (Omp31) and L7/L12 are immunodominant and protective antigens conserved in human Brucella pathogens. In the present study, we evaluated the humoral and cellular immune responses induced by a fusion protein designed based on the Truncated form of Omp31 (TOmp31) and L7-L12 antigens. Vaccination of BALB/c mice with the recombinant fusion protein (rL7/L12-TOmp31) provided the significant protection level against B. melitensis and B. abortus challenge. Moreover, rL7/L12-TOmp31 elicited a strong specific IgG response (higher IgG2a titers) and significant IFN-γ/IL2 production and T-cell proliferation was also observed. The T helper1 (Th1) oriented response persisted for 12 weeks after the first immunization. The rL7/L12-TOmp31 could be a new potential antigen candidate for the development of a subunit vaccine against B. melitensis and B. abortus. Copyright © 2015 Elsevier Ltd. All rights reserved.

Liposome-antigen-nucleic acid complexes protect mice from lethal challenge with western and eastern equine encephalitis viruses.

PubMed

Phillips, Aaron T; Schountz, Tony; Toth, Ann M; Rico, Amber B; Jarvis, Donald L; Powers, Ann M; Olson, Ken E

2014-02-01

Alphaviruses are mosquito-borne viruses that cause significant disease in animals and humans. Western equine encephalitis virus (WEEV) and eastern equine encephalitis virus (EEEV), two New World alphaviruses, can cause fatal encephalitis, and EEEV is a select agent of concern in biodefense. However, we have no antiviral therapies against alphaviral disease, and current vaccine strategies target only a single alphavirus species. In an effort to develop new tools for a broader response to outbreaks, we designed and tested a novel alphavirus vaccine comprised of cationic lipid nucleic acid complexes (CLNCs) and the ectodomain of WEEV E1 protein (E1ecto). Interestingly, we found that the CLNC component, alone, had therapeutic efficacy, as it increased survival of CD-1 mice following lethal WEEV infection. Immunization with the CLNC-WEEV E1ecto mixture (lipid-antigen-nucleic acid complexes [LANACs]) using a prime-boost regimen provided 100% protection in mice challenged with WEEV subcutaneously, intranasally, or via mosquito. Mice immunized with LANACs mounted a strong humoral immune response but did not produce neutralizing antibodies. Passive transfer of serum from LANAC E1ecto-immunized mice to nonimmune CD-1 mice conferred protection against WEEV challenge, indicating that antibody is sufficient for protection. In addition, the LANAC E1ecto immunization protocol significantly increased survival of mice following intranasal or subcutaneous challenge with EEEV. In summary, our LANAC formulation has therapeutic potential and is an effective vaccine strategy that offers protection against two distinct species of alphavirus irrespective of the route of infection. We discuss plausible mechanisms as well the potential utility of our LANAC formulation as a pan-alphavirus vaccine.

Protection by universal influenza vaccine is mediated by memory CD4 T cells.

PubMed

Valkenburg, Sophie A; Li, Olive T W; Li, Athena; Bull, Maireid; Waldmann, Thomas A; Perera, Liyanage P; Peiris, Malik; Poon, Leo L M

2018-07-05

There is a diverse array of influenza viruses which circulate between different species, reassort and drift over time. Current seasonal influenza vaccines are ineffective in controlling these viruses. We have developed a novel universal vaccine which elicits robust T cell responses and protection against diverse influenza viruses in mouse and human models. Vaccine mediated protection was dependent on influenza-specific CD4 + T cells, whereby depletion of CD4 + T cells at either vaccination or challenge time points significantly reduced survival in mice. Vaccine memory CD4 + T cells were needed for early antibody production and CD8 + T cell recall responses. Furthermore, influenza-specific CD4 + T cells from vaccination manifested primarily Tfh and Th1 profiles with anti-viral cytokine production. The vaccine boosted H5-specific T cells from human PBMCs, specifically CD4 + and CD8 + T effector memory type, ensuring the vaccine was truly universal for its future application. These findings have implications for the development and optimization of T cell activating vaccines for universal immunity against influenza. Copyright © 2018 Elsevier Ltd. All rights reserved.

Safety, immunogencity, and efficacy of a cold-adapted A/Ann Arbor/6/60 (H2N2) vaccine in mice and ferrets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Grace L., E-mail: chengra@niaid.nih.go; Lamirande, Elaine W., E-mail: elamirande@niaid.nih.go; Jin Hong, E-mail: jinh@medimmune.co

We studied the attenuation, immunogenicity and efficacy of the cold-adapted A/Ann Arbor/6/60 (AA ca) (H2N2) virus in mice and ferrets to evaluate its use in the event of an H2 influenza pandemic. The AA ca virus was restricted in replication in the respiratory tract of mice and ferrets. In mice, 2 doses of vaccine elicited a > 4-fold rise in hemagglutination-inhibition (HAI) titer and resulted in complete inhibition of viral replication following lethal homologous wild-type virus challenge. In ferrets, a single dose of the vaccine elicited a > 4-fold rise in HAI titer and conferred complete protection against homologous wild-typemore » virus challenge in the upper respiratory tract. In both mice and ferrets, the AA ca virus provided significant protection from challenge with heterologous H2 virus challenge in the respiratory tract. The AA ca vaccine is safe, immunogenic, and efficacious against homologous and heterologous challenge in mice and ferrets, supporting the evaluation of this vaccine in clinical trials.« less

A single, low dose of a cGMP recombinant BCG vaccine elicits protective T cell immunity against the human respiratory syncytial virus infection and prevents lung pathology in mice.

PubMed

Céspedes, Pablo F; Rey-Jurado, Emma; Espinoza, Janyra A; Rivera, Claudia A; Canedo-Marroquín, Gisela; Bueno, Susan M; Kalergis, Alexis M

2017-02-01

Human respiratory syncytial virus (hRSV) is a major health burden worldwide, causing the majority of hospitalizations in children under two years old due to bronchiolitis and pneumonia. HRSV causes year-to-year outbreaks of disease, which also affects the elderly and immunocompromised adults. Furthermore, both hRSV morbidity and epidemics are explained by a consistently high rate of re-infections that take place throughout the patient life. Although significant efforts have been invested worldwide, currently there are no licensed vaccines to prevent hRSV infection. Here, we describe that a recombinant Bacillus Calmette-Guerin (BCG) vaccine expressing the nucleoprotein (N) of hRSV formulated under current good manufacture practices (cGMP rBCG-N-hRSV) confers protective immunity to the virus in mice. Our results show that a single dose of the GMP rBCG-N-hRSV vaccine retains its capacity to protect mice against a challenge with a disease-causing infection of 1×10 7 plaque-forming units (PFUs) of the hRSV A2 clinical strain 13018-8. Compared to unimmunized infected controls, vaccinated mice displayed reduced weight loss and less infiltration of neutrophils within the airways, as well as reduced viral loads in bronchoalveolar lavages, parameters that are characteristic of hRSV infection in mice. Also, ex vivo re-stimulation of splenic T cells at 28days post-immunization activated a repertoire of T cells secreting IFN-γ and IL-17, which further suggest that the rBCG-N-hRSV vaccine induced a mixed, CD8 + and CD4 + T cell response capable of both restraining viral spread and preventing damage of the lungs. All these features support the notion that rBCG-N-hRSV is a promising candidate vaccine to be used in humans to prevent the disease caused by hRSV in the susceptible population. Copyright © 2016 Elsevier Ltd. All rights reserved.

Construction and immune effect of Haemophilus parasuis DNA vaccine encoding glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in mice.

PubMed

Fu, Shulin; Zhang, Minmin; Ou, Jiwen; Liu, Huazhen; Tan, Chen; Liu, Jinlin; Chen, Huanchun; Bei, Weicheng

2012-11-06

Haemophilus parasuis, the causative agent of swine polyserositis, polyarthritis, and meningitis, is one of the most important bacterial diseases of pigs worldwide. The development of a vaccine against H. parasuis has been impeded due to the lack of induction of reliable cross-serotype protection. In this study the gapA gene that encodes glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was shown to be present and highly conserved in various serotypes of H. parasuis and we constructed a novel DNA vaccine encoding GAPDH (pCgap) to evaluate the immune response and protective efficacy against infection with H. parasuis MD0322 serovar 4 or SH0165 serovar 5 in mice. A significant antibody response against GAPDH was generated following pCgap intramuscular immunization; moreover, antibodies to the pCgap DNA vaccine were bactericidal, suggesting that it was expressed in vivo. The gapA transcript was detected in muscle, liver, spleen, and kidney of the mice seven days post-vaccination. The IgG subclass (IgG1 and IgG2a) analysis indicated that the DNA vaccine induced both Th1 and Th2 immune responses, but the IgG1 response was greater than the IgG2a response. Moreover, the groups vaccinated with the pCgap vaccine exhibited 83.3% and 50% protective efficacy against the H. parasuis MD0322 serovar 4 or SH0165 serovar 5 challenges, respectively. The pCgap DNA vaccine provided significantly greater protective efficacy compared to the negative control groups or blank control groups (P<0.05 for both). Taken together, these findings indicate that the pCgap DNA vaccine provides a novel strategy against infection of H. parasuis and offer insight concerning the underlying immune mechanisms of a bacterial DNA vaccine. Copyright © 2012 Elsevier Ltd. All rights reserved.

Intranasal bacille Calmette–Guérin (BCG) vaccine dosage needs balancing between protection and lung pathology

PubMed Central

TREE, J A; WILLIAMS, A; CLARK, S; HALL, G; MARSH, P D; IVANYI, J

2004-01-01

Intranasal vaccination may offer practical benefits and better protection against respiratory infections, including tuberculosis. In this paper, we investigated the persistence of the Mycobacterium bovis-strain bacille Calmette–Guérin (BCG) Pasteur, lung granuloma formation and protection against pathogenic tuberculous challenge in mice. A pronounced BCG dose-dependent granulomatous infiltration of the lungs was observed following intranasal, but not after subcutaneous, vaccination. Corresponding doses of BCG, over a 100-fold range, imparted similar protection against H37Rv challenge when comparing the intranasal and subcutaneous vaccination routes. Interestingly, a BCG dose-dependent reduction of the H37Rv challenge infection was observed in the lungs, but not in the spleens, following both intranasal and subcutaneous vaccination. In the light of the observed concurrence between the extent of granuloma formation and the level of protection of the lungs, we conclude that intranasal vaccination leading to best protective efficacy needs to be balanced with an acceptable safety margin avoiding undue pathology in the lungs. PMID:15544615

Smallpox DNA Vaccine Delivered by Novel Skin Electroporation Device Protects Mice Against Intranasal Poxvirus Challenge

DTIC Science & Technology

2006-11-27

response being elicited by microneedle -mediated skin electroporation. 2006 Elsevier Ltd. All rights reserved. i o a p ( c o t t v H f r eywords...localized skin infection containing infectious virus (i.e., ock), the infection can spread to other sites on the body e.g., ocular autoinoculation) or to...plasmid DNA-coated microneedle arrays. Mice vaccinated with the 4pox DNA vaccine mounted robust antibody responses against the four immunogens-of-interest

A Recombinant Raccoon Poxvirus Vaccine Expressing both Yersinia pestis F1 and Truncated V Antigens Protects Animals against Lethal Plague

PubMed Central

Rocke, Tonie E.; Kingstad-Bakke, Brock; Berlier, Willy; Osorio, Jorge E.

2014-01-01

In previous studies, we demonstrated in mice and prairie dogs that simultaneous administration of two recombinant raccoon poxviruses (rRCN) expressing Yersinia pestis antigens (F1 and V307—a truncated version of the V protein) provided superior protection against plague challenge compared to individual single antigen constructs. To reduce costs of vaccine production and facilitate implementation of a sylvatic plague vaccine (SPV) control program for prairie dogs, a dual antigen construct is more desirable. Here we report the construction and characterization of a novel RCN-vectored vaccine that simultaneously expresses both F1 and V307 antigens. This dual antigen vaccine provided similar levels of protection against plague in both mice and prairie dogs as compared to simultaneous administration of the two single antigen constructs and was also shown to protect mice against an F1 negative strain of Y. pestis. The equivalent safety, immunogenicity and efficacy profile of the dual RCN-F1/V307 construct warrants further evaluation in field efficacy studies in sylvatic plague endemic areas. PMID:26344891

A recombinant raccoon poxvirus vaccine expressing both Yersinia pestis F1 and truncated V antigens protects animals against lethal plague.

USGS Publications Warehouse

Rocke, Tonie E.; Kingstad-Bakke, B; Berlier, W; Osorio, J.E.

2014-01-01

In previous studies, we demonstrated in mice and prairie dogs that simultaneous administration of two recombinant raccoon poxviruses (rRCN) expressing Yersinia pestis antigens (F1 and V307-a truncated version of the V protein) provided superior protection against plague challenge compared to individual single antigen constructs. To reduce costs of vaccine production and facilitate implementation of a sylvatic plague vaccine (SPV) control program for prairie dogs, a dual antigen construct is more desirable. Here we report the construction and characterization of a novel RCN-vectored vaccine that simultaneously expresses both F1 and V307 antigens. This dual antigen vaccine provided similar levels of protection against plague in both mice and prairie dogs as compared to simultaneous administration of the two single antigen constructs and was also shown to protect mice against an F1 negative strain of Y. pestis.. The equivalent safety, immunogenicity and efficacy profile of the dual RCN-F1/V307 construct warrants further evaluation in field efficacy studies in sylvatic plague endemic areas.

A Highly Immunogenic and Protective Middle East Respiratory Syndrome Coronavirus Vaccine Based on a Recombinant Measles Virus Vaccine Platform

PubMed Central

Malczyk, Anna H.; Kupke, Alexandra; Prüfer, Steffen; Scheuplein, Vivian A.; Hutzler, Stefan; Kreuz, Dorothea; Beissert, Tim; Bauer, Stefanie; Hubich-Rau, Stefanie; Tondera, Christiane; Eldin, Hosam Shams; Schmidt, Jörg; Vergara-Alert, Júlia; Süzer, Yasemin; Seifried, Janna; Hanschmann, Kay-Martin; Kalinke, Ulrich; Herold, Susanne; Sahin, Ugur; Cichutek, Klaus; Waibler, Zoe; Eickmann, Markus; Becker, Stephan

2015-01-01

ABSTRACT In 2012, the first cases of infection with the Middle East respiratory syndrome coronavirus (MERS-CoV) were identified. Since then, more than 1,000 cases of MERS-CoV infection have been confirmed; infection is typically associated with considerable morbidity and, in approximately 30% of cases, mortality. Currently, there is no protective vaccine available. Replication-competent recombinant measles virus (MV) expressing foreign antigens constitutes a promising tool to induce protective immunity against corresponding pathogens. Therefore, we generated MVs expressing the spike glycoprotein of MERS-CoV in its full-length (MERS-S) or a truncated, soluble variant of MERS-S (MERS-solS). The genes encoding MERS-S and MERS-solS were cloned into the vaccine strain MVvac2 genome, and the respective viruses were rescued (MVvac2-CoV-S and MVvac2-CoV-solS). These recombinant MVs were amplified and characterized at passages 3 and 10. The replication of MVvac2-CoV-S in Vero cells turned out to be comparable to that of the control virus MVvac2-GFP (encoding green fluorescent protein), while titers of MVvac2-CoV-solS were impaired approximately 3-fold. The genomic stability and expression of the inserted antigens were confirmed via sequencing of viral cDNA and immunoblot analysis. In vivo, immunization of type I interferon receptor-deficient (IFNAR−/−)-CD46Ge mice with 2 × 105 50% tissue culture infective doses of MVvac2-CoV-S(H) or MVvac2-CoV-solS(H) in a prime-boost regimen induced robust levels of both MV- and MERS-CoV-neutralizing antibodies. Additionally, induction of specific T cells was demonstrated by T cell proliferation, antigen-specific T cell cytotoxicity, and gamma interferon secretion after stimulation of splenocytes with MERS-CoV-S presented by murine dendritic cells. MERS-CoV challenge experiments indicated the protective capacity of these immune responses in vaccinated mice. IMPORTANCE Although MERS-CoV has not yet acquired extensive distribution

Immunogenicity and protective efficacy of Semliki forest virus replicon-based DNA vaccines encoding goatpox virus structural proteins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng Min; Guangxi Center for Animal Disease Control and Prevention, Nanning 530001; College of Animal Science and Veterinary Medicine, Jilin University, Changchun 130062

Goatpox, caused by goatpox virus (GTPV), is an acute feverish and contagious disease in goats often associated with high morbidity and high mortality. To resolve potential safety risks and vaccination side effects of existing live attenuated goatpox vaccine (AV41), two Semliki forest virus (SFV) replicon-based bicistronic expression DNA vaccines (pCSm-AAL and pCSm-BAA) which encode GTPV structural proteins corresponding to the Vaccinia virus proteins A27, L1, A33, and B5, respectively, were constructed. Then, theirs ability to induce humoral and cellular response in mice and goats, and protect goats against virulent virus challenge were evaluated. The results showed that, vaccination with pCSm-AALmore » and pCSm-BAA in combination could elicit strong humoral and cellular responses in mice and goats, provide partial protection against viral challenge in goats, and reduce disease symptoms. Additionally, priming vaccination with the above-mentioned DNA vaccines could significantly reduce the goats' side reactions from boosting vaccinations with current live vaccine (AV41), which include skin lesions at the inoculation site and fevers. Data obtained in this study could not only facilitate improvement of the current goatpox vaccination strategy, but also provide valuable guidance to suitable candidates for evaluation and development of orthopoxvirus vaccines.« less

Protective efficacy of a Mycoplasma pneumoniae P1C DNA vaccine fused with the B subunit of Escherichia coli heat-labile enterotoxin.

PubMed

Zhu, Cuiming; Wang, Shiping; Hu, Shihai; Yu, Minjun; Zeng, Yanhua; You, Xiaoxing; Xiao, Jinhong; Wu, Yimou

2012-06-01

In the present study, we investigated the immunomodulatory responses of a DNA vaccine constructed by fusing Mycoplasma pneumoniae P1 protein carboxy terminal region (P1C) with the Escherichia coli heat-labile toxin B subunit (LTB). BALB/c mice were immunized by intranasal inoculation with control DNAs, the P1C DNA vaccine or the LTB-P1C fusion DNA vaccine. Levels of the anti-M. pneumoniae antibodies and levels of interferon-γ and IL-4 in mice were increased significantly upon inoculation of the LTB-P1C fusion DNA vaccine when compared with the inoculation with P1C DNA vaccine. The LTB-P1C fusion DNA vaccine efficiently enhanced the M. pneumoniae-specific IgA and IgG levels. The IgG2a/IgG1 ratio was significantly higher in bronchoalveolar lavages fluid and sera from mice fusion with LTB and P1C than mice receiving P1C alone. When the mice were challenged intranasally with 10(7) CFU M. pneumoniae strain (M129), the LTB-P1C fusion DNA vaccine conferred significantly better protection than P1C DNA vaccine (P < 0.05), as suggested by the results, such as less inflammation, lower histopathological score values, lower detectable number of M. pneumoniae strain, and lower mortality of challenging from 5 × 10(8) CFU M. pneumoniae. These results indicated that the LTB-P1C fusion DNA vaccine efficiently improved protective efficacy against M. pneumoniae infection and effectively attenuated development of M. pneumoniae in mice.

A prime-boost immunization regimen based on a simian adenovirus 36 vectored multi-stage malaria vaccine induces protective immunity in mice.

PubMed

Fonseca, Jairo A; McCaffery, Jessica N; Kashentseva, Elena; Singh, Balwan; Dmitriev, Igor P; Curiel, David T; Moreno, Alberto

2017-05-31

Malaria remains a considerable burden on public health. In 2015, the WHO estimates there were 212 million malaria cases causing nearly 429,000 deaths globally. A highly effective malaria vaccine is needed to reduce the burden of this disease. We have developed an experimental vaccine candidate (PyCMP) based on pre-erythrocytic (CSP) and erythrocytic (MSP1) stage antigens derived from the rodent malaria parasite P. yoelii. Our protein-based vaccine construct induces protective antibodies and CD4 + T cell responses. Based on evidence that viral vectors increase CD8 + T cell-mediated immunity, we also have tested heterologous prime-boost immunization regimens that included human adenovirus serotype 5 vector (Ad5), obtaining protective CD8 + T cell responses. While Ad5 is commonly used for vaccine studies, the high prevalence of pre-existing immunity to Ad5 severely compromises its utility. Here, we report the use of the novel simian adenovirus 36 (SAd36) as a candidate for a vectored malaria vaccine since this virus is not known to infect humans, and it is not neutralized by anti-Ad5 antibodies. Our study shows that the recombinant SAd36PyCMP can enhance specific CD8 + T cell response and elicit similar antibody titers when compared to an immunization regimen including the recombinant Ad5PyCMP. The robust immune responses induced by SAd36PyCMP are translated into a lower parasite load following P. yoelii infectious challenge when compared to mice immunized with Ad5PyCMP. Copyright © 2017 Elsevier Ltd. All rights reserved.

Monoclonal antibodies passively protect BALB/c mice against Burkholderia mallei aerosol challenge.

PubMed

Treviño, Sylvia R; Permenter, Amy R; England, Marilyn J; Parthasarathy, Narayanan; Gibbs, Paul H; Waag, David M; Chanh, Tran C

2006-03-01

Glanders is a debilitating disease with no vaccine available. Murine monoclonal antibodies were produced against Burkholderia mallei, the etiologic agent of glanders, and were shown to be effective in passively protecting mice against a lethal aerosol challenge. The antibodies appeared to target lipopolysaccharide. Humoral antibodies may be important for immune protection against B. mallei infection.

Complex adenovirus-vectored vaccine protects guinea pigs from three strains of Marburg virus challenges.

PubMed

Wang, Danher; Hevey, Michael; Juompan, Laure Y; Trubey, Charles M; Raja, Nicholas U; Deitz, Stephen B; Woraratanadharm, Jan; Luo, Min; Yu, Hong; Swain, Benjamin M; Moore, Kevin M; Dong, John Y

2006-09-30

The Marburg virus (MARV), an African filovirus closely related to the Ebola virus, causes a deadly hemorrhagic fever in humans, with up to 90% mortality. Currently, treatment of disease is only supportive, and no vaccines are available to prevent spread of MARV infections. In order to address this need, we have developed and characterized a novel recombinant vaccine that utilizes a single complex adenovirus-vectored vaccine (cAdVax) to overexpress a MARV glycoprotein (GP) fusion protein derived from the Musoke and Ci67 strains of MARV. Vaccination with the cAdVaxM(fus) vaccine led to efficient production of MARV-specific antibodies in both mice and guinea pigs. Significantly, guinea pigs vaccinated with at least 5 x 10(7) pfu of cAdVaxM(fus) vaccine were 100% protected against lethal challenges by the Musoke, Ci67 and Ravn strains of MARV, making it a vaccine with trivalent protective efficacy. Therefore, the cAdVaxM(fus) vaccine serves as a promising vaccine candidate to prevent and contain multi-strain infections by MARV.

Complex adenovirus-vectored vaccine protects guinea pigs from three strains of Marburg virus challenges

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang Danher; Hevey, Michael; Juompan, Laure Y.

2006-09-30

The Marburg virus (MARV), an African filovirus closely related to the Ebola virus, causes a deadly hemorrhagic fever in humans, with up to 90% mortality. Currently, treatment of disease is only supportive, and no vaccines are available to prevent spread of MARV infections. In order to address this need, we have developed and characterized a novel recombinant vaccine that utilizes a single complex adenovirus-vectored vaccine (cAdVax) to overexpress a MARV glycoprotein (GP) fusion protein derived from the Musoke and Ci67 strains of MARV. Vaccination with the cAdVaxM(fus) vaccine led to efficient production of MARV-specific antibodies in both mice and guineamore » pigs. Significantly, guinea pigs vaccinated with at least 5 x 10{sup 7} pfu of cAdVaxM(fus) vaccine were 100% protected against lethal challenges by the Musoke, Ci67 and Ravn strains of MARV, making it a vaccine with trivalent protective efficacy. Therefore, the cAdVaxM(fus) vaccine serves as a promising vaccine candidate to prevent and contain multi-strain infections by MARV.« less

In contrast to conventional inactivated influenza vaccines, 4xM2e.HSP70c fusion protein fully protected mice against lethal dose of H1, H3 and H9 influenza A isolates circulating in Iran

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ebrahimi, Seyyed Mahmoud, E-mail: smebrahimi@shirazu.ac.ir; Research Center of Virus and Vaccine, Baqiyatallah University of Medical Science, P.O.Box 14155-3651, Tehran; Dabaghian, Mehran

Ideal vaccines against influenza viruses should elicit not only a humoral response, but also a cellular response. Mycobacterium tuberculosis HSP70 (mHSP70) have been found to promote immunogenic APCs function, elicit a strong cytotoxic T lymphocyte (CTL) response, and prevent the induction of tolerance. Moreover, it showed linkage of antigens to the C-terminus of mHSP70 (mHSP70c) can represent them as vaccines resulted in more potent, protective antigen specific responses in the absence of adjuvants or complex formulations. Hence, recombinant fusion protein comprising C-terminus of mHSP70 genetically fused to four tandem repeats of the ectodomain of the conserved influenza matrix protein M2more » (M2e) was expressed in Escherichia coli, purified under denaturing condition, refolding, and then confirmed by SDS-PAGE, respectively. The recombinant fusion protein, 4xM2e.HSP70c, retained its immunogenicity and displayed the protective epitope of M2e by ELISA and FITC assays. A prime-boost administration of 4xM2e.HSP70c formulated in F105 buffer by intramuscular route in mice (Balb/C) provided full protection against lethal dose of mouse-adapted H1N1, H3N2, or H9N2 influenza A isolates from Iran compared to 0-33.34% survival rate of challenged unimmunized and immunized mice with the currently in use conventional vaccines designated as control groups. However, protection induced by immunization with 4xM2e.HSP70c failed to prevent weight loss in challenged mice; they experienced significantly lower weight loss, clinical symptoms and higher lung viral clearance in comparison with protective effects of conventional influenza vaccines in challenged mice. These data demonstrate that C-terminal domain of mHSP70 can be a superior candidate to deliver the adjuvant function in M2e-based influenza A vaccine in order to provide significant protection against multiple influenza A virus strains.« less

Immunogenicity and Protection of Oral Influenza Vaccines Formulated into Microparticles

PubMed Central

SHASTRI, PRATHAP NAGARAJA; KIM, MIN-CHUL; QUAN, FU-SHI; D’SOUZA, MARTIN J.; KANG, SANG-MOO

2017-01-01

Influenza is a deadly disease affecting humans and animals. It is recommended that every individual should be vaccinated annually against influenza. Considering the frequency of administration of this vaccine, we have explored the oral route of vaccination with a microparticulate formulation. Microparticles containing inactivated influenza A/PR/34/8 H1N1 virus with Eudragit S and trehalose as a matrix were prepared using the Buchi spray dryer. Particle size distribution of microparticles was measured and the bioactivity of vaccine in a microparticle form was analyzed using a hemagglutination activity test. Furthermore, the efficacy of microparticle vaccines was evaluated in vivo in Balb/c mice. Analysis of serum samples showed that microparticles resulted in enhanced antigen-specific immunoglobulin G (IgG), IgG1, and IgG2a antibodies. Upon challenge with homologous and heterologous influenza viruses, microparticle vaccines showed significantly increased levels of protection. Use of microparticles to deliver vaccines could be a promising tool for the development of an oral influenza vaccine. PMID:22711602

The Contribution of Systemic and Pulmonary Immune Effectors to Vaccine-Induced Protection from H5N1 Influenza Virus Infection

PubMed Central

Lau, Yuk-Fai; Wright, Amber R.

2012-01-01

Live attenuated influenza vaccines (LAIVs) are effective in providing protection against influenza challenge in animal models and in preventing disease in humans. We previously showed that LAIVs elicit a range of immune effectors and that successful induction of pulmonary cellular and humoral immunity in mice requires pulmonary replication of the vaccine virus. An upper respiratory tract immunization (URTI) model was developed in mice to mimic the human situation, in which the vaccine virus does not replicate in the lower respiratory tract, allowing us to assess the protective efficacy of an H5N1 LAIV against highly pathogenic H5N1 virus challenge in the absence of significant pulmonary immunity. Our results show that, after one dose of an H5N1 LAIV, pulmonary influenza-specific lymphocytes are the main contributors to clearance of challenge virus from the lungs and that contributions of influenza-specific enzyme-linked immunosorbent assay (ELISA) antibodies in serum and splenic CD8+ T cells were negligible. Complete protection from H5N1 challenge was achieved after two doses of H5N1 LAIV and was associated with maturation of the antibody response. Although passive transfer of sera from mice that received two doses of vaccine prevented lethality in naive recipients following challenge, the mice showed significant weight loss, with high pulmonary titers of the H5N1 virus. These data highlight the importance of mucosal immunity in mediating optimal protection against H5N1 infection. Understanding the requirements for effective induction and establishment of these protective immune effectors in the respiratory tract paves the way for a more rational and effective vaccine approach in the future. PMID:22379093

Partial reconstitution of the CD4+-T-cell compartment in CD4 gene knockout mice restores responses to tuberculosis DNA vaccines.

PubMed

D'Souza, Sushila; Romano, Marta; Korf, Johanna; Wang, Xiao-Ming; Adnet, Pierre-Yves; Huygen, Kris

2006-05-01

Reactivation tuberculosis (TB) is a serious problem in immunocompromised individuals, especially those with human immunodeficiency virus (HIV) coinfection. The adaptive immune response mediated by CD4+ and CD8+ T cells is known to confer protection against TB. Hence, vaccines against TB are designed to activate these two components of the immune system. Anti-TB DNA vaccines encoding the immunodominant proteins Ag85A, Ag85B, and PstS-3 from Mycobacterium tuberculosis are ineffective in mice lacking CD4+ T cells (CD4-/- mice). In this study, we demonstrate that reconstitution of the T-cell compartment in CD4-/- mice restores vaccine-specific antibody and gamma interferon (IFN-gamma) responses to these DNA vaccines. The magnitude of the immune responses correlated with the extent of reconstitution of the CD4+-T-cell compartment. Reconstituted mice vaccinated with DNA encoding PstS-3, known to encode a dominant D(b)-restricted CD8+-T-cell epitope, displayed CD8+-T-cell responses not observed in CD4-/- mice. M. tuberculosis challenge in reconstituted mice led to the extravasation of IFN-gamma-producing CD4+ and CD8+ T cells into lungs, the primary site of bacterial replication. Importantly, a reconstitution of 12 to 15% of the CD4+-T-cell compartment resulted in Ag85B plasmid DNA-mediated protection against a challenge M. tuberculosis infection. Our findings provide evidence that anti-TB DNA vaccines could be effective in immunodeficient individuals after CD4+-T-lymphocyte reconstitution, as may occur following antiretroviral therapy in HIV+ patients.

Chitosan Microsphere Used as an Effective System to Deliver a Linked Antigenic Peptides Vaccine Protect Mice Against Acute and Chronic Toxoplasmosis.

PubMed

Guo, Jingjing; Sun, Xiahui; Yin, Huiquan; Wang, Ting; Li, Yan; Zhou, Chunxue; Zhou, Huaiyu; He, Shenyi; Cong, Hua

2018-01-01

Multiple antigenic peptide (MAP) vaccines have advantages over traditional Toxoplasma gondii vaccines, but are more susceptible to enzymatic degradation. As an effective delivery system, chitosan microspheres (CS) can overcome this obstacle and act as a natural adjuvant to promote T helper 1 (Th1) cellular immune responses. In this study, we use chitosan microparticles to deliver multiple antigenic epitopes from GRA10 (G10E), containing three dominant epitopes. When G10E was entrapped within chitosan microparticles (G10E-CS), adequate peptides for eliciting immune response were loaded in the microsphere core and this complex released G10E peptides stably. The efficiency of G10E-CS was detected both in vitro , via cell culture, and through in vivo mouse immunization. In vitro , G10E-CS activated Dendritic Cells (DC) and T lymphocytes by upregulating the secretion of costimulatory molecules (CD40 and CD86). In vivo , Th1 biased cellular and humoral immune responses were activated in mice vaccinated with G10E-CS, accompanied by significantly increased production of IFN-γ, IL-2, and IgG, and decreases in IL-4, IL-10, and IgG1. Immunization with G10E-CS conferred significant protection with prolonged survival in mice model of acute toxoplasmosis and statistically significant decreases in cyst burden in murine chronic toxoplasmosis. The results from this study indicate that chitosan microspheres used as an effective system to deliver a linked antigenic peptides is a promising strategy for the development of efficient vaccine against T. gondii .

Trivalent pneumococcal protein recombinant vaccine protects against lethal Streptococcus pneumoniae pneumonia and correlates with phagocytosis by neutrophils during early pathogenesis.

PubMed

Xu, Qingfu; Surendran, Naveen; Verhoeven, David; Klapa, Jessica; Ochs, Martina; Pichichero, Michael E

2015-02-18

Due to the fact that current polysaccharide-based pneumococcal vaccines have limited serotype coverage, protein-based vaccine candidates have been sought for over a decade to replace or complement current vaccines. We previously reported that a trivalent Pneumococcal Protein recombinant Vaccine (PPrV), showed protection against pneumonia and sepsis in an infant murine model. Here we investigated immunological correlates of protection of PPrV in the same model. C57BL/6J infant mice were intramuscularly vaccinated at age 1-3 weeks with 3 doses of PPrV, containing pneumococcal histidine triad protein D (PhtD), pneumococcal choline binding protein A (PcpA), and detoxified pneumolysin mutant PlyD1. 3-4 weeks after last vaccination, serum and lung antibody levels to PPrV components were measured, and mice were intranasally challenged with a lethal dose of Streptococcus pneumoniae (Spn) serotype 6A. Lung Spn bacterial burden, number of neutrophils and alveolar macrophages, phagocytosed Spn by granulocytes, and levels of cytokines and chemokines were determined at 6, 12, 24, and 48h after challenge. PPrV vaccination conferred 83% protection against Spn challenge. Vaccinated mice had significantly elevated serum and lung antibody levels to three PPrV components. In the first stage of pathogenesis of Spn induced pneumonia (6-24h after challenge), vaccinated mice had lower Spn bacterial lung burdens and more phagocytosed Spn in the granulocytes. PPrV vaccination led to lower levels of pro-inflammatory cytokines IL-6, IL-1β, and TFN-α, and other cytokines and chemokines (IL-12, IL-17, IFN-γ, MIP-1b, MIP-2 and KC, and G-CSF), presumably due to a lower lung bacterial burden. Trivalent PPrV vaccination results in increased serum and lung antibody levels to the vaccine components, a reduction in Spn induced lethality, enhanced early clearance of Spn in lungs due to more rapid and thorough phagocytosis of Spn by neutrophils, and correspondingly a reduction in lung inflammation

Insect cell-produced recombinant protein subunit vaccines protect against Zika virus infection.

PubMed

Qu, Panke; Zhang, Wei; Li, Dapeng; Zhang, Chao; Liu, Qingwei; Zhang, Xueyang; Wang, Xuesong; Dai, Wenlong; Xu, Yongfen; Leng, Qibin; Zhong, Jin; Jin, Xia; Huang, Zhong

2018-06-01

Infection with Zika virus (ZIKV) may lead to severe neurologic disorders. It is of significant importance and urgency to develop safe and effective vaccines to prevent ZIKV infection. Here we report the development of ZIKV subunit vaccines based on insect cell-produced recombinant proteins. The N-terminal approximately 80% region (designated as E80) and the domain III (designated as EDIII) of ZIKV envelope (E) protein were efficiently produced as secreted proteins in a Drosophila S2 cell expression system. Both E80 and EDIII could inhibit ZIKV infection in vitro, suggesting that they may have folded properly to display native conformations. Immunization studies demonstrated that both E80 and EDIII vaccines were able to trigger antigen-specific antibody and T-cell responses in mice. The resulting anti-E80 and anti-EDIII sera could potently neutralize ZIKV infection in vitro. More importantly, passive transfer of either anti-E80 or anti-EDIII sera protected recipient mice against lethal ZIKV challenge. It is worth noting that the anti-EDIII sera possessed higher neutralizing titers and conferred more complete protection than the anti-E80 sera, indicating that the S2 cell-produced EDIII is a superior ZIKV vaccine candidate compared with the E80. These data support further preclinical and clinical development of a ZIKV subunit vaccine based on S2 cell-produced EDIII. Copyright © 2018 Elsevier B.V. All rights reserved.

Long-Term Immunogenicity of an Inactivated Split-Virion 2009 Pandemic Influenza A H1N1 Virus Vaccine with or without Aluminum Adjuvant in Mice

PubMed Central

Xu, Wenting; Zheng, Mei; Zhou, Feng

2015-01-01

In 2009, a global epidemic of influenza A(H1N1) virus caused the death of tens of thousands of people. Vaccination is the most effective means of controlling an epidemic of influenza and reducing the mortality rate. In this study, the long-term immunogenicity of influenza A/California/7/2009 (H1N1) split vaccine was observed as long as 15 months (450 days) after immunization in a mouse model. Female BALB/c mice were immunized intraperitoneally with different doses of aluminum-adjuvanted vaccine. The mice were challenged with a lethal dose (10× 50% lethal dose [LD50]) of homologous virus 450 days after immunization. The results showed that the supplemented aluminum adjuvant not only effectively enhanced the protective effect of the vaccine but also reduced the immunizing dose of the vaccine. In addition, the aluminum adjuvant enhanced the IgG antibody level of mice immunized with the H1N1 split vaccine. The IgG level was correlated to the survival rate of the mice. Aluminum-adjuvanted inactivated split-virion 2009 pandemic influenza A H1N1 vaccine has good immunogenicity and provided long-term protection against lethal influenza virus challenge in mice. PMID:25589552

Interleukin-12 Induces a Th1-Like Response to Burkholderia mallei and Limited Protection in BALB/c Mice

DTIC Science & Technology

2006-01-01

sublethal and lethal intraperitoneal glanders ( Burkholderia mallei ). Vet Pathol 2000;37:626–36. [34] Jankovic D, Caspar P, Zweig M, Garcia-Moll M...Vaccine 24 (2006) 1413–1420 Interleukin-12 induces a Th1-like response to Burkholderia mallei and limited protection in BALB/c mice Kei Amemiya...IL)-12 on the immune response to Burkholderia mallei in BALB/c mice. Mice were vaccinated with non-viable B. mallei cells with or without IL-12

Protection against Streptococcus suis Serotype 2 Infection Using a Capsular Polysaccharide Glycoconjugate Vaccine

PubMed Central

Calzas, Cynthia; Shiao, Tze Chieh; Neubauer, Axel; Kempker, Jennifer; Roy, René; Gottschalk, Marcelo

2016-01-01

Streptococcus suis serotype 2 is an encapsulated bacterium and one of the most important bacterial pathogens in the porcine industry. Despite decades of research for an efficient vaccine, none is currently available. Based on the success achieved with other encapsulated pathogens, a glycoconjugate vaccine strategy was selected to elicit opsonizing anti-capsular polysaccharide (anti-CPS) IgG antibodies. In this work, glycoconjugate prototypes were prepared by coupling S. suis type 2 CPS to tetanus toxoid, and the immunological features of the postconjugation preparations were evaluated in vivo. In mice, experiments evaluating three different adjuvants showed that CpG oligodeoxyribonucleotide (ODN) induces very low levels of anti-CPS IgM antibodies, while the emulsifying adjuvants Stimune and TiterMax Gold both induced high levels of IgGs and IgM. Dose-response trials comparing free CPS with the conjugate vaccine showed that free CPS is nonimmunogenic independently of the dose used, while 25 μg of the conjugate preparation was optimal in inducing high levels of anti-CPS IgGs postboost. With an opsonophagocytosis assay using murine whole blood, sera from immunized mice showed functional activity. Finally, the conjugate vaccine showed immunogenicity and induced protection in a swine challenge model. When conjugated and administered with emulsifying adjuvants, S. suis type 2 CPS is able to induce potent IgM and isotype-switched IgGs in mice and pigs, yielding functional activity in vitro and protection against a lethal challenge in vivo, all features of a T cell-dependent response. This study represents a proof of concept for the potential of glycoconjugate vaccines in veterinary medicine applications against invasive bacterial infections. PMID:27113360

Salmonella enterica serovar Choleraesuis vector delivering SaoA antigen confers protection against Streptococcus suis serotypes 2 and 7 in mice and pigs.

PubMed

Li, Yu-An; Ji, Zhenying; Wang, Xiaobo; Wang, Shifeng; Shi, Huoying

2017-12-21

Streptococcus suis is one of the major pathogens that cause economic losses in the swine industry worldwide. However, current bacterins only provide limited prophylactic protection in the field. An ideal vaccine against S. suis should protect pigs against the clinical diseases caused by multiple serotypes, or at least protect against the dominant serotype in a given geographic region. A new recombinant Salmonella enterica serotype Choleraesuis vaccine vector, rSC0011, that is based on the regulated delayed attenuation system and regulated delayed antigen synthesis system, was developed recently. In this study, an improved recombinant attenuated Salmonella Choleraesuis vector, rSC0016, was developed by incorporating a sopB mutation to ensure adequate safety and maximal immunogenicity. In the spleens of mice, rSC0016 colonized less than rSC0011. rSC0016 and rSC0011 colonized similarly in Peyer's patches of mice. The recombinant vaccine rSC0016(pS-SaoA) induced stronger cellular, humoral, and mucosal immune responses in mice and swine against SaoA, a conserved surface protein that is present in many S. suis serotypes, than did rSC0011(pS-SaoA) without sopB or rSC0018(pS-SaoA), which is an avirulent, chemically attenuated vaccine strain. rSC0016(pS-SaoA) provided 100% protection against S. suis serotype 2 in mice and pigs, and full cross-protection against SS7 in pigs. This new vaccine vector provides a foundation for the development of a universal vaccine against multiple serotypes of S. suis in pigs.

Protection against experimental bubonic and pneumonic plague by a recombinant capsular F1-V antigen fusion protein vaccine.

PubMed

Heath, D G; Anderson, G W; Mauro, J M; Welkos, S L; Andrews, G P; Adamovicz, J; Friedlander, A M

1998-07-01

The current human whole-cell vaccine is ineffective against pneumonic plague caused by typical F1 capsule positive (F1+) strains of Yersinia pestis. The authors found this vaccine to also be ineffective against F1-negative (F1-) Y. pestis strains, which have been isolated from a human case and from rodents. For these reasons, the authors developed a recombinant vaccine composed of a fusion protein of F1 with a second protective immunogen, V antigen. This vaccine protected experimental mice against pneumonic as well as bubonic plague produced by either an F1+ or F1- strain of Y. pestis, gave better protection than F1 or V alone against the F1+ strain, and may provide the basis for an improved human plague vaccine.

BALB/c mice display more enhanced BCG vaccine induced Th1 and Th17 response than C57BL/6 mice but have equivalent protection.

PubMed

Garcia-Pelayo, M Carmen; Bachy, Véronique S; Kaveh, Daryan A; Hogarth, Philip J

2015-01-01

It is generally assumed that the inbred mouse strains BALB/c (H-2(d)) and C57BL/6 (H-2(b)) respond to mycobacterial infection with distinct polarisation of T helper responses, with C57BL/6 predisposed to Th1 and BALB/c to Th2. We investigated this in a BCG-immunisation, Mycobacterium bovis challenge model. Following immunisation, lung and spleen cell cytokine responses to in vitro re-stimulation with a cocktail of seven secreted, immunogenic, recombinant mycobacterial proteins were determined. In both lung and spleen, BALB/c cells produced at least 2-fold more IFN-γ, and up to 7-fold more IL-2 and IL-17 than C57BL/6 cells, whereas IL-10 production was reciprocally increased in C57BL/6 mice. These data suggest that, contrary to reports in the literature, specific mycobacterial antigens are able to induce strong Th1 and Th17 responses in BALB/c mice following BCG vaccination, whilst in C57BL/6 mice, the Th1 response is partly counterbalanced by IL-10. After subsequent M. bovis low dose challenge, protection, as measured in the lungs and dissemination to the spleen, was equivalent in BALB/c and C57BL/6 mice, indicating that BCG-induced immunity was equivalent in both strains. Thus, the differential immune responses do not appear to have a role in protection, but further, as yet unidentified, specific immune responses play a significant role. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Inactivated Influenza Vaccine That Provides Rapid, Innate-Immune-System-Mediated Protection and Subsequent Long-Term Adaptive Immunity.

PubMed

Chua, Brendon Y; Wong, Chinn Yi; Mifsud, Edin J; Edenborough, Kathryn M; Sekiya, Toshiki; Tan, Amabel C L; Mercuri, Francesca; Rockman, Steve; Chen, Weisan; Turner, Stephen J; Doherty, Peter C; Kelso, Anne; Brown, Lorena E; Jackson, David C

2015-10-27

The continual threat to global health posed by influenza has led to increased efforts to improve the effectiveness of influenza vaccines for use in epidemics and pandemics. We show in this study that formulation of a low dose of inactivated detergent-split influenza vaccine with a Toll-like receptor 2 (TLR2) agonist-based lipopeptide adjuvant (R4Pam2Cys) provides (i) immediate, antigen-independent immunity mediated by the innate immune system and (ii) significant enhancement of antigen-dependent immunity which exhibits an increased breadth of effector function. Intranasal administration of mice with vaccine formulated with R4Pam2Cys but not vaccine alone provides protection against both homologous and serologically distinct (heterologous) viral strains within a day of administration. Vaccination in the presence of R4Pam2Cys subsequently also induces high levels of systemic IgM, IgG1, and IgG2b antibodies and pulmonary IgA antibodies that inhibit hemagglutination (HA) and neuraminidase (NA) activities of homologous but not heterologous virus. Improved primary virus nucleoprotein (NP)-specific CD8(+) T cell responses are also induced by the use of R4Pam2Cys and are associated with robust recall responses to provide heterologous protection. These protective effects are demonstrated in wild-type and antibody-deficient animals but not in those depleted of CD8(+) T cells. Using a contact-dependent virus transmission model, we also found that heterologous virus transmission from vaccinated mice to naive mice is significantly reduced. These results demonstrate the potential of adding a TLR2 agonist to an existing seasonal influenza vaccine to improve its utility by inducing immediate short-term nonspecific antiviral protection and also antigen-specific responses to provide homologous and heterologous immunity. The innate and adaptive immune systems differ in mechanisms, specificities, and times at which they take effect. The innate immune system responds within hours of

Enhanced Immune Response and Protective Effects of Nano-chitosan-based DNA Vaccine Encoding T Cell Epitopes of Esat-6 and FL against Mycobacterium Tuberculosis Infection

PubMed Central

Feng, Ganzhu; Jiang, Qingtao; Xia, Mei; Lu, Yanlai; Qiu, Wen; Zhao, Dan; Lu, Liwei; Peng, Guangyong; Wang, Yingwei

2013-01-01

Development of a novel and effective vaccine against Mycobacterium tuberculosis (M.tb) is a challenging for preventing TB infection. In this study, a novel nanoparticle-based recombinant DNA vaccine was developed, which contains Esat-6 three T cell epitopes (Esat-6/3e) and fms-like tyrosine kinase 3 ligand (FL) genes (termed Esat-6/3e-FL), and was enveloped with chitosan (CS) nanoparticles (nano-chitosan). The immunologic and protective efficacy of the nano-chitosan-based DNA vaccine (termed nano-Esat-6/3e-FL) was assessed in C57BL/6 mice after intramuscular prime vaccination with the plasmids DNA and nasal boost with the Esat-6/3e peptides. The results showed that the immunized mice remarkably elicited enhanced T cell responses and protection against M.tb H37Rv challenge. These findings indicate that the nano-chitosan can significantly elevate the immunologic and protective effects of the DNA vaccine, and the nano-Esat-6/3e-FL is a useful vaccine for preventing M.tb infection in mice. PMID:23637790

Immunological and protective effects of Bordetella bronchiseptica subunit vaccines based on the recombinant N-terminal domain of dermonecrotic toxin.

PubMed

Wang, Chuanwen; Liu, Liping; Zhang, Zhen; Yan, Zhengui; Yu, Cuilian; Shao, Mingxu; Jiang, Xiaodong; Chi, Shanshan; Wei, Kai; Zhu, Ruiliang

2015-10-01

Dermonecrotic toxin (DNT) produced by Bordetella bronchiseptica (B. bronchiseptica) can cause clinical turbinate atrophy in swine and induce dermonecrotic lesions in model mice. We know that the N-terminal of DNT molecule contains the receptor-binding domain, which facilitates binding to the target cells. However, we do not know whether this domain has sufficient immunogenicity to resist B. bronchiseptica damage and thereby to develop a subunit vaccine for the swine industry. In this study, we prokaryotically expressed the recombinant N-terminal of DNT from B. bronchiseptica (named DNT-N) and prepared it for the subunit vaccine to evaluate its immunogenicity. Taishan Pinus massoniana pollen polysaccharide (TPPPS), a known immunomodulator, was used as the adjuvant to examine its immune-conditioning effects. At 49 d after inoculation, 10 mice from each group were challenged with B. bronchiseptica, and another 10 mice were intradermally challenged with native DNT, to examine the protection imparted by the vaccines. The immune parameters (T-lymphocyte counts, cytokine secretions, serum antibody titers, and survival rates) and skin lesions were determined. The results showed that pure DNT-N vaccine significantly induced immune responses and had limited ability to resist the B. bronchiseptica and DNT challenge, whereas the mice administered with TPPPS or Freund's incomplete adjuvant vaccine could induce higher levels of the above immune parameters. Remarkably, the DNT-N vaccine combined with TPPPS adjuvant protected the mice effectively to prevent B. bronchiseptica infection. Our findings indicated that DNT-N has potential for development as an effective subunit vaccine to counteract the damage of B. bronchiseptica infection, especially when used conjointly with TPPPS. Copyright © 2015 Elsevier B.V. All rights reserved.

Thermostable ricin vaccine protects rhesus macaques against aerosolized ricin: Epitope-specific neutralizing antibodies correlate with protection.

PubMed

Roy, Chad J; Brey, Robert N; Mantis, Nicholas J; Mapes, Kelly; Pop, Iliodora V; Pop, Laurentiu M; Ruback, Stephen; Killeen, Stephanie Z; Doyle-Meyers, Lara; Vinet-Oliphant, Heather S; Didier, Peter J; Vitetta, Ellen S

2015-03-24

Ricin toxin (RT) is the second most lethal toxin known; it has been designated by the CDC as a select agent. RT is made by the castor bean plant; an estimated 50,000 tons of RT are produced annually as a by-product of castor oil. RT has two subunits, a ribotoxic A chain (RTA) and galactose-binding B chain (RTB). RT binds to all mammalian cells and once internalized, a single RTA catalytically inactivates all of the ribosomes in a cell. Administered as an aerosol, RT causes rapid lung damage and fibrosis followed by death. There are no Food and Drug Administration-approved vaccines and treatments are only effective in the first few hours after exposure. We have developed a recombinant RTA vaccine that has two mutations V76M/Y80A (RiVax). The protein is expressed in Escherichia coli and is nontoxic and immunogenic in mice, rabbits, and humans. When vaccinated mice are challenged with injected, aerosolized, or orally administered (gavaged) RT, they are completely protected. We have now developed a thermostable, aluminum-adjuvant-containing formulation of RiVax and tested it in rhesus macaques. After three injections, the animals developed antibodies that completely protected them from a lethal dose of aerosolized RT. These antibodies neutralized RT and competed to varying degrees with a panel of neutralizing and nonneutralizing mouse monoclonal antibodies known to recognize specific epitopes on native RTA. The resulting antibody competition profile could represent an immunologic signature of protection. Importantly, the same signature was observed using sera from RiVax-immunized humans.

Correlates of protection for enteric vaccines.

PubMed

Holmgren, Jan; Parashar, Umesh D; Plotkin, Stanley; Louis, Jacques; Ng, Su-Peing; Desauziers, Eric; Picot, Valentina; Saadatian-Elahi, Mitra

2017-06-08

An immunological Correlate of Protection (CoP) is an immune response that is statistically interrelated with protection. Identification of CoPs for enteric vaccines would help design studies to improve vaccine performance of licensed vaccines in low income settings, and would facilitate the testing of future vaccines in development that might be more affordable. CoPs are lacking today for most existing and investigational enteric vaccines. In order to share the latest information on CoPs for enteric vaccines and to discuss novel approaches to correlate mucosal immune responses in humans with protection, the Foundation Mérieux organized an international conference of experts where potential CoPs for vaccines were examined using case-studies for both bacterial and viral enteric pathogens. Experts on the panel concluded that to date, all established enteric vaccine CoPs, such as those for hepatitis A, Vi typhoid and poliovirus vaccines, are based on serological immune responses even though these may poorly reflect the relevant gut immune responses or predict protective efficacy. Known CoPs for cholera, norovirus and rotavirus could be considered as acceptable for comparisons of similarly composed vaccines while more work is still needed to establish CoPs for the remaining enteric pathogens and their candidate vaccines. Novel approaches to correlate human mucosal immune responses with protection include the investigation of gut-originating antibody-secreting cells (ASCs), B memory cells and follicular helper T cells from samples of peripheral blood during their recirculation. Copyright © 2017.

Vaccinia-based influenza vaccine overcomes previously induced immunodominance hierarchy for heterosubtypic protection.

PubMed

Kwon, Ji-Sun; Yoon, Jungsoon; Kim, Yeon-Jung; Kang, Kyuho; Woo, Sunje; Jung, Dea-Im; Song, Man Ki; Kim, Eun-Ha; Kwon, Hyeok-Il; Choi, Young Ki; Kim, Jihye; Lee, Jeewon; Yoon, Yeup; Shin, Eui-Cheol; Youn, Jin-Won

2014-08-01

Growing concerns about unpredictable influenza pandemics require a broadly protective vaccine against diverse influenza strains. One of the promising approaches was a T cell-based vaccine, but the narrow breadth of T-cell immunity due to the immunodominance hierarchy established by previous influenza infection and efficacy against only mild challenge condition are important hurdles to overcome. To model T-cell immunodominance hierarchy in humans in an experimental setting, influenza-primed C57BL/6 mice were chosen and boosted with a mixture of vaccinia recombinants, individually expressing consensus sequences from avian, swine, and human isolates of influenza internal proteins. As determined by IFN-γ ELISPOT and polyfunctional cytokine secretion, the vaccinia recombinants of influenza expanded the breadth of T-cell responses to include subdominant and even minor epitopes. Vaccine groups were successfully protected against 100 LD50 challenges with PR/8/34 and highly pathogenic avian influenza H5N1, which contained the identical dominant NP366 epitope. Interestingly, in challenge with pandemic A/Cal/04/2009 containing mutations in the dominant epitope, only the group vaccinated with rVV-NP + PA showed improved protection. Taken together, a vaccinia-based influenza vaccine expressing conserved internal proteins improved the breadth of influenza-specific T-cell immunity and provided heterosubtypic protection against immunologically close as well as distant influenza strains. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Recombinant vaccine displaying the loop-neutralizing determinant from protective antigen completely protects rabbits from experimental inhalation anthrax.

PubMed

Oscherwitz, Jon; Yu, Fen; Jacobs, Jana L; Cease, Kemp B

2013-03-01

We previously showed that a multiple antigenic peptide (MAP) vaccine displaying amino acids (aa) 304 to 319 from the 2β2-2β3 loop of protective antigen was capable of protecting rabbits from an aerosolized spore challenge with Bacillus anthracis Ames strain. Antibodies to this sequence, referred to as the loop-neutralizing determinant (LND), are highly potent at neutralizing lethal toxin yet are virtually absent in rabbit and human protective antigen (PA) antiserum. While the MAP vaccine was protective against anthrax, it contains a single heterologous helper T cell epitope which may be suboptimal for stimulating an outbred human population. We therefore engineered a recombinant vaccine (Rec-LND) containing two tandemly repeated copies of the LND fused to maltose binding protein, with enhanced immunogenicity resulting from the p38/P4 helper T cell epitope from Schistosoma mansoni. Rec-LND was found to be highly immunogenic in four major histocompatibility complex (MHC)-diverse strains of mice. All (7/7) rabbits immunized with Rec-LND developed high-titer antibody, 6 out of 7 developed neutralizing antibody, and all rabbits were protected from an aerosolized spore challenge of 193 50% lethal doses (LD(50)) of the B. anthracis Ames strain. Survivor serum from Rec-LND-immunized rabbits revealed significantly increased neutralization titers and specific activity compared to prechallenge levels yet lacked PA or lethal factor (LF) antigenemia. Control rabbits immunized with PA, which were also completely protected, appeared sterilely immune, exhibiting significant declines in neutralization titer and specific activity compared to prechallenge levels. We conclude that Rec-LND may represent a prototype anthrax vaccine for use alone or potentially combined with PA-containing vaccines.

Immunization with the recombinant antigen Ss-IR induces protective immunity to infection with Strongyloides stercoralis in mice.

PubMed

Abraham, David; Hess, Jessica A; Mejia, Rojelio; Nolan, Thomas J; Lok, James B; Lustigman, Sara; Nutman, Thomas B

2011-10-19

Human intestinal infections with the nematode Strongyloides stercoralis remain a significant problem worldwide and a vaccine would be a useful addition to the tools available to prevent and control this infection. The goal of this study was to test single antigens for their efficacy in a vaccine against S. stercoralis larvae in mice. Alum was used as the adjuvant in these studies and antigens selected for analysis were either recognized by protective human IgG (Ss-TMY-1, Ss-EAT-6, and Ss-LEC-5) or were known to be highly immunogenic in humans (Ss-NIE-1 and Ss-IR). Only mice immunized with the Ss-IR antigen demonstrated a significant decrease of approximately 80% in the survival of larval parasites in the challenge infection. Antibodies, recovered from mice with protective immunity to S. stercoralis after immunization with Ss-IR, were used to locate the antigen in the larvae. Confocal microscopy revealed that IgG from mice immunized with Ss-IR bound to the surface of the parasites and observations by electron microscopy indicated that IgG bound to granules in the glandular esophagus. Serum collected from mice immunized with Ss-IR passively transferred immunity to naïve mice. These studies demonstrate that Ss-IR, in combination with alum, induces high levels of protective immunity through an antibody dependent mechanism and may therefore be suitable for further development as a vaccine against human strongyloidiasis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Intranasal hydroxypropyl-β-cyclodextrin-adjuvanted influenza vaccine protects against sub-heterologous virus infection.

PubMed

Kusakabe, Takato; Ozasa, Koji; Kobari, Shingo; Momota, Masatoshi; Kishishita, Natsuko; Kobiyama, Kouji; Kuroda, Etsushi; Ishii, Ken J

2016-06-08

Intranasal vaccination with inactivated influenza viral antigens is an attractive and valid alternative to currently available influenza (flu) vaccines; many of which seem to need efficient and safe adjuvant, however. In this study, we examined whether hydroxypropyl-β-cyclodextrin (HP-β-CD), a widely used pharmaceutical excipient to improve solubility and drug delivery, can act as a mucosal adjuvant for intranasal flu vaccines. We found that intranasal immunization of mice with hemagglutinin split- as well as inactivated whole-virion influenza vaccine with HP-β-CD resulted in secretion of antigen-specific IgA and IgGs in the airway mucosa and the serum as well. As a result, both HP-β-CD adjuvanted-flu intranasal vaccine protected mice against lethal challenge with influenza virus, equivalent to those induced by experimental cholera toxin-adjuvanted ones. Of note, intranasal use of HP-β-CD as an adjuvant induced significantly lower antigen-specific IgE responses than that induced by aluminum salt adjuvant. These results suggest that HP-β-CD may be a potent mucosal adjuvant for seasonal and pandemic influenza vaccine. Copyright © 2016 Elsevier Ltd. All rights reserved.

Inactivated Eyedrop Influenza Vaccine Adjuvanted with Poly(I:C) Is Safe and Effective for Inducing Protective Systemic and Mucosal Immunity

PubMed Central

Kim, Eun-Do; Han, Soo Jung; Byun, Young-Ho; Yoon, Sang Chul; Choi, Kyoung Sub; Seong, Baik Lin; Seo, Kyoung Yul

2015-01-01

The eye route has been evaluated as an efficient vaccine delivery routes. However, in order to induce sufficient antibody production with inactivated vaccine, testing of the safety and efficacy of the use of inactivated antigen plus adjuvant is needed. Here, we assessed various types of adjuvants in eyedrop as an anti-influenza serum and mucosal Ab production-enhancer in BALB/c mice. Among the adjuvants, poly (I:C) showed as much enhancement in antigen-specific serum IgG and mucosal IgA antibody production as cholera toxin (CT) after vaccinations with trivalent hemagglutinin-subunits or split H1N1 vaccine antigen in mice. Vaccination with split H1N1 eyedrop vaccine antigen plus poly(I:C) showed a similar or slightly lower efficacy in inducing antibody production than intranasal vaccination; the eyedrop vaccine-induced immunity was enough to protect mice from lethal homologous influenza A/California/04/09 (H1N1) virus challenge. Additionally, ocular inoculation with poly(I:C) plus vaccine antigen generated no signs of inflammation within 24 hours: no increases in the mRNA expression levels of inflammatory cytokines nor in the infiltration of mononuclear cells to administration sites. In contrast, CT administration induced increased expression of IL-6 cytokine mRNA and mononuclear cell infiltration in the conjunctiva within 24 hours of vaccination. Moreover, inoculated visualizing materials by eyedrop did not contaminate the surface of the olfactory bulb in mice; meanwhile, intranasally administered materials defiled the surface of the brain. On the basis of these findings, we propose that the use of eyedrop inactivated influenza vaccine plus poly(I:C) is a safe and effective mucosal vaccine strategy for inducing protective anti-influenza immunity. PMID:26355295

Immunogenicity and protective efficacy of heterologous prime-boost regimens with mycobacterial vaccines and recombinant adenovirus- and poxvirus-vectored vaccines against murine tuberculosis.

PubMed

You, Qingrui; Wu, Yongge; Wu, Yang; Wei, Wei; Wang, Changyong; Jiang, Dehua; Yu, Xianghui; Zhang, Xizhen; Wang, Yong; Tang, Zhijiao; Jiang, Chunlai; Kong, Wei

2012-11-01

To evaluate regimens using bacillus Calmette-Guérin (BCG) or recombinant BCG (rBCG) overexpressing Ag85B for priming, followed by boosting with a modified vaccinia virus Ankara strain (MVA) and/or adenovirus vector (AD) expressing an Ag85B-ESAT6 fusion protein. Cellular and humoral immune responses were determined after subcutaneous vaccination, which was employed to trigger systemic immunity against intravenous infection in a mouse model of tuberculosis (TB). Bacterial loads and lung histology were evaluated. The relative IgG2a and IgG1 antibody levels indicated that the viral-vectored vaccines generated a T-helper type 1 (Th1)-biased response after two doses of viral boost vaccinations. Boosting BCG-primed mice with viral vaccines induced a Th1 immune response that included both CD4 and CD8 T-cells generating antigen-specific interferon-gamma (IFN-γ) and CD8 T cytotoxic activity. Only mice vaccinated with two different viral boosters after BCG priming exhibited a significant reduction in bacterial burden in the lung after challenge. Histology examinations confirmed the attenuation of lung damage and more compact granulomas. After mycobacteria priming, boosting with AD85B-E6 followed by MVA85B-E6 afforded better protection than the reverse order of administration of the viral vectors. This study demonstrates the potential of multiple heterologous viral booster vaccines, although the exact correlates of protection and optimal regimens should be further investigated for the rational design of future vaccine strategies. Copyright © 2012 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Protection of bats (Eptesicus fuscus) against rabies following topical or oronasal exposure to a recombinant raccoon poxvirus vaccine.

PubMed

Stading, Ben; Ellison, James A; Carson, William C; Satheshkumar, Panayampalli Subbian; Rocke, Tonie E; Osorio, Jorge E

2017-10-01

Rabies is an ancient neglected tropical disease that causes tens of thousands of human deaths and millions of cattle deaths annually. In order to develop a new vaccine for potential use in bats, a reservoir of rabies infection for humans and animals alike, an in silico antigen designer tool was used to create a mosaic glycoprotein (MoG) gene using available sequences from the rabies Phylogroup I glycoprotein. This sequence, which represents strains more likely to occur in bats, was cloned into raccoonpox virus (RCN) and the efficacy of this novel RCN-MoG vaccine was compared to RCN-G that expresses the glycoprotein gene from CVS-11 rabies or luciferase (RCN-luc, negative control) in mice and big brown bats (Eptesicus fuscus). Mice vaccinated and boosted intradermally with 1 x 107 plaque forming units (PFU) of each RCN-rabies vaccine construct developed neutralizing antibodies and survived at significantly higher rates than controls. No significant difference in antibody titers or survival was noted between rabies-vaccinated groups. Bats were vaccinated either oronasally (RCN-G, RCN-MoG) with 5x107 PFU or by topical application in glycerin jelly (RCN-MoG, dose 2x108 PFU), boosted (same dose and route) at 46 days post vaccination (dpv), and then challenged with wild-type big brown variant RABV at 65 dpv. Prior to challenge, 90% of RCN-G and 75% of RCN-MoG oronasally vaccinated bats had detectable levels of serum rabies neutralizing antibodies. Bats from the RCN-luc and topically vaccinated RCN-MoG groups did not have measurable antibody responses. The RCN-rabies constructs were highly protective and not significantly different from each other. RCN-MoG provided 100% protection (n = 9) when delivered oronasally and 83% protection (n = 6) when delivered topically; protection provided by the RCN-G construct was 70% (n = 10). All rabies-vaccinated bats survived at a significantly (P ≤ 0.02) higher rate than control bats (12%; n = 8). We have demonstrated the efficacy of

Protection of bats (Eptesicus fuscus) against rabies following topical or oronasal exposure to a recombinant raccoon poxvirus vaccine

PubMed Central

Stading, Ben; Ellison, James A.; Carson, William C.; Satheshkumar, Panayampalli Subbian; Osorio, Jorge E.

2017-01-01

Rabies is an ancient neglected tropical disease that causes tens of thousands of human deaths and millions of cattle deaths annually. In order to develop a new vaccine for potential use in bats, a reservoir of rabies infection for humans and animals alike, an in silico antigen designer tool was used to create a mosaic glycoprotein (MoG) gene using available sequences from the rabies Phylogroup I glycoprotein. This sequence, which represents strains more likely to occur in bats, was cloned into raccoonpox virus (RCN) and the efficacy of this novel RCN-MoG vaccine was compared to RCN-G that expresses the glycoprotein gene from CVS-11 rabies or luciferase (RCN-luc, negative control) in mice and big brown bats (Eptesicus fuscus). Mice vaccinated and boosted intradermally with 1 x 107 plaque forming units (PFU) of each RCN-rabies vaccine construct developed neutralizing antibodies and survived at significantly higher rates than controls. No significant difference in antibody titers or survival was noted between rabies-vaccinated groups. Bats were vaccinated either oronasally (RCN-G, RCN-MoG) with 5x107 PFU or by topical application in glycerin jelly (RCN-MoG, dose 2x108 PFU), boosted (same dose and route) at 46 days post vaccination (dpv), and then challenged with wild-type big brown variant RABV at 65 dpv. Prior to challenge, 90% of RCN-G and 75% of RCN-MoG oronasally vaccinated bats had detectable levels of serum rabies neutralizing antibodies. Bats from the RCN-luc and topically vaccinated RCN-MoG groups did not have measurable antibody responses. The RCN-rabies constructs were highly protective and not significantly different from each other. RCN-MoG provided 100% protection (n = 9) when delivered oronasally and 83% protection (n = 6) when delivered topically; protection provided by the RCN-G construct was 70% (n = 10). All rabies-vaccinated bats survived at a significantly (P ≤ 0.02) higher rate than control bats (12%; n = 8). We have demonstrated the efficacy of

Protection of bats (Eptesicus fuscus) against rabies following topical or oronasal exposure to a recombinant raccoon poxvirus vaccine

USGS Publications Warehouse

Stading, Ben; Ellison, James A.; Carson, William C.; Satheshkumar, Panayampalli Subbian; Rocke, Tonie E.; Osorio, Jorge E.

2017-01-01

Rabies is an ancient neglected tropical disease that causes tens of thousands of human deaths and millions of cattle deaths annually. In order to develop a new vaccine for potential use in bats, a reservoir of rabies infection for humans and animals alike, an in silico antigen designer tool was used to create a mosaic glycoprotein (MoG) gene using available sequences from the rabies Phylogroup I glycoprotein. This sequence, which represents strains more likely to occur in bats, was cloned into raccoonpox virus (RCN) and the efficacy of this novel RCN-MoG vaccine was compared to RCN-G that expresses the glycoprotein gene from CVS-11 rabies or luciferase (RCN-luc, negative control) in mice and big brown bats (Eptesicus fuscus). Mice vaccinated and boosted intradermally with 1 x 107 plaque forming units (PFU) of each RCN-rabies vaccine construct developed neutralizing antibodies and survived at significantly higher rates than controls. No significant difference in antibody titers or survival was noted between rabies-vaccinated groups. Bats were vaccinated either oronasally (RCN-G, RCN-MoG) with 5x107 PFU or by topical application in glycerin jelly (RCN-MoG, dose 2x108 PFU), boosted (same dose and route) at 46 days post vaccination (dpv), and then challenged with wild-type big brown variant RABV at 65 dpv. Prior to challenge, 90% of RCN-G and 75% of RCN-MoG oronasally vaccinated bats had detectable levels of serum rabies neutralizing antibodies. Bats from the RCN-luc and topically vaccinated RCN-MoG groups did not have measurable antibody responses. The RCN-rabies constructs were highly protective and not significantly different from each other. RCN-MoG provided 100% protection (n = 9) when delivered oronasally and 83% protection (n = 6) when delivered topically; protection provided by the RCN-G construct was 70% (n = 10). All rabies-vaccinated bats survived at a significantly (P ≤ 0.02) higher rate than control bats (12%; n = 8). We have demonstrated the

Vaccination with recombinant adenoviruses expressing Ebola virus glycoprotein elicits protection in the interferon alpha/beta receptor knock-out mouse.

PubMed

O'Brien, Lyn M; Stokes, Margaret G; Lonsdale, Stephen G; Maslowski, David R; Smither, Sophie J; Lever, Mark S; Laws, Thomas R; Perkins, Stuart D

2014-03-01

The resistance of adult immunocompetent mice to infection with ebolaviruses has led to the development of alternative small animal models that utilise immunodeficient mice, for example the interferon α/β receptor knock-out mouse (IFNR(-/-)). IFNR(-/-) mice have been shown to be susceptible to infection with ebolaviruses by multiple routes but it is not known if this murine model is suitable for testing therapeutics that rely on the generation of an immune response for efficacy. We have tested recombinant adenovirus vectors for their ability to protect IFNR(-/-) mice from challenge with Ebola virus and have analysed the humoral response generated after immunisation. The recombinant vaccines elicited good levels of protection in the knock-out mouse and the antibody response in IFNR(-/-) mice was similar to that observed in vaccinated wild-type mice. These results indicate that the IFNR(-/-) mouse is a relevant small animal model for studying ebolavirus-specific therapeutics. Copyright © 2014. Published by Elsevier Inc.

Vaccine potential of recombinant cathepsinL1G against Fasciola gigantica in mice.

PubMed

Changklungmoa, Narin; Phoinok, Natthacha; Yencham, Chonthicha; Sobhon, Prasert; Kueakhai, Pornanan

2016-08-15

In this study, we characterized and investigated the vaccine potential of FgCatL1G against Fasciola gigantica infection in mice. Recombinant mature FgCatL1G (rmFgCatL1G) was expressed in Escherichia coli BL21. The vaccination was performed in Imprinting Control Region (ICR) mice (n=10) by subcutaneous injection with 50μg of rmFgCatL1G combined with Freund's adjuvant. Two weeks after the second boost, mice were infected with 15 metacercariae by the oral route. The percents of protection of rmFgCatL1G vaccine were estimated to be 56.5% and 58.3% when compared with non vaccinated-infected and adjuvant-infected controls, respectively. Antibodies in the immune sera of vaccinated mice were shown by immunoblot to react with the native FgCatL1s in the extract of all stages of parasites and rmFgCatL1H, recombinant pro - FgCatL1 (rpFgCatL1). By immunohistochemistry, the immune sera also reacted with FgCatL1s in the caecal epithelial cells of the parasites. The levels of IgG1 and IgG2a in the immune sera, which are indicative of Th2 and Th1 immune responses, were also increased with IgG1 predominating. The levels of serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) in rmFgCatL1G-immunized group showed no significant difference from the control groups, but pathological lesions of livers in rmFgCatL1G-immunized group showed significant decrease when compared to the control groups. This study indicates that rmFgCatL1G has a vaccine potential against F. gigantica in mice, and this potential will be tested in larger livestock animals. Copyright © 2016 Elsevier B.V. All rights reserved.

A plant-produced protective antigen vaccine confers protection in rabbits against a lethal aerosolized challenge with Bacillus anthracis Ames spores.

PubMed

Chichester, Jessica A; Manceva, Slobodanka D; Rhee, Amy; Coffin, Megan V; Musiychuk, Konstantin; Mett, Vadim; Shamloul, Moneim; Norikane, Joey; Streatfield, Stephen J; Yusibov, Vidadi

2013-03-01

The potential use of Bacillus anthracis as a bioterrorism weapon threatens the security of populations globally, requiring the immediate availability of safe, efficient and easily delivered anthrax vaccine for mass vaccination. Extensive research efforts have been directed toward the development of recombinant subunit vaccines based on protective antigen (PA), the principal virulence factor of B. anthracis. Among the emerging technologies for the production of these vaccine antigens is our launch vector-based plant transient expression system. Using this system, we have successfully engineered, expressed, purified and characterized full-length PA (pp-PA83) in Nicotiana benthamiana plants using agroinfiltration. This plant-produced antigen elicited high toxin neutralizing antibody titers in mice and rabbits after two vaccine administrations with Alhydrogel. In addition, immunization with this vaccine candidate protected 100% of rabbits from a lethal aerosolized B. anthracis challenge. The vaccine effects were dose-dependent and required the presence of Alhydrogel adjuvant. In addition, the vaccine antigen formulated with Alhydrogel was stable and retained immunogenicity after two-week storage at 4°C, the conditions intended for clinical use. These results support the testing of this vaccine candidate in human volunteers and the utility of our plant expression system for the production of a recombinant anthrax vaccine.

Oral immunization with recombinant enterovirus 71 VP1 formulated with chitosan protects mice against lethal challenge

PubMed Central

2014-01-01

Background Enterovirus 71 (EV71) is the etiologic agent of hand-foot-and-mouth disease (HFMD) in the Asia-Pacific region, Many strategies have been applied to develop EV71 vaccines but no vaccines are currently available. Mucosal immunization of the VP1, a major immunogenic capsid protein of EV71, may be an alternative way to prevent EV71 infection. Results In this study, mucosal immunogenicity and protect function of recombinant VP1 protein (rVP1) in formulation with chitosan were tested and assessed in female ICR mouse model. The results showed that the oral immunization with rVP1 induced VP1-specific IgA antibodies in intestine, feces, vagina, and the respiratory tract and serum-specific IgG and neutralization antibodies in vaccinated mice. Splenocytes from rVP1-immunized mice induced high levels of Th1 (cytokine IFN-γ), Th2 (cytokine IL-4) and Th3 (cytokine TGF-β) type immune responses after stimulation. Moreover, rVP1-immunized mother mice conferred protection (survival rate up to 30%) on neonatal mice against a lethal challenge of 103 plaque-forming units (PFU) EV71. Conclusions These data indicated that oral immunization with rVP1 in formulation with chitosan was effective in inducing broad-spectrum immune responses and might be a promising subunit vaccine candidate for preventing EV71 infection. PMID:24885121

Virus neutralizing antibody response in mice and dogs with a bicistronic DNA vaccine encoding rabies virus glycoprotein and canine parvovirus VP2.

PubMed

Patial, Sonika; Chaturvedi, V K; Rai, A; Saini, M; Chandra, Rajesh; Saini, Y; Gupta, Praveen K

2007-05-16

A bicistronic DNA vaccine against rabies and parvovirus infection of dogs was developed by subcloning rabies glycoprotein and canine parvovirus (CPV) VP2 genes into a bicistronic vector. After characterizing the expression of both the proteins in vitro, the bicistronic DNA vaccine was injected in mice and induced immune response was compared with monocistronic DNA vaccines. There was no significant difference in ELISA and virus neutralizing (VN) antibody responses against rabies and CPV in mice immunized with either bicistronic or monocistronic DNA vaccine. Further, there was significantly similar protection in mice immunized with either bicistronic or monocistronic rabies DNA vaccine on rabies virus challenge. Similarly, dogs immunized with monocistronic and bicistronic DNA vaccines developed comparable VN antibodies against rabies and CPV. This study indicated that bicistronic DNA vaccine can be used in dogs to induce virus neutralizing immune responses against both rabies and CPV.

PROTECTION AGAINST TYPHOID-LIKE INFECTIONS BY VACCINATION

PubMed Central

Nichols, Henry J.; Stimmel, Clarence O.

1923-01-01

1. A natural infection of guinea pigs with the "mutton" strain of Bacillus aertrycke was used to test the protective power of vaccination against the typhoid group of infections. 2. Under the conditions of the experiment, complete protection was secured by vaccination with full strength fresh saline vaccine, while 100 per cent of deaths occurred among the controls. 3. The immunity acquired is variable and depends on the number of organisms injected. 4. Vaccine kept 10 to 14 months gave less protection than vaccine 8 months old and under. 5. Saline vaccine was more effective than lipovaccine, sensitized vaccine, or supernatant fluid vaccine. 6. Resuspended vaccine was as effective as the original vaccine. 7. In one experiment, group vaccine, made of typhoid Para A and Para B bacilli, was as effective as the original specific vaccine. PMID:19868790

Evaluation of the persistence of vaccine-induced protection with human vaccines.

PubMed

Vidor, E

2010-01-01

The persistence of protection induced by vaccines is a key aspect of the implementation of human vaccination policies, particularly for ageing populations. At the time of initial licensure, the duration of protection induced by a vaccine is generally only documented by longitudinal follow up of cohorts of subjects enrolled in the pre-licensure trials over a period of 1-5 years. The follow up of these cohorts provides two types of data: antibody kinetics (or another clinically relevant immunological parameter) over time and the disease incidence. Generally, the latter trials, if implemented during the pre-licensure period, are designed to follow-up cohorts in order to demonstrate vaccine efficacy above the minimal level required for the license. For vaccines already licensed, additional tools exist. The use of immunological surrogate markers of protection is a practical way to monitor the duration of protection. Measuring the persistence of circulating antibodies is widely used in human vaccines. For several vaccines, observed data have allowed the creation of mathematical models to predict the antibody persistence over periods of time longer than those effectively documented. Clinical trials assessing the capacity of the immune system to mount a quick anamnestic response upon re-stimulation a long time after initial priming (measurement of immune memory) is also a tool employed to document the duration of protection. The waning of protection can also be demonstrated by an increase of disease incidence in the subsequent 'time-to-last-vaccine administration' age segments. Seroprevalence studies in a given age group of people that were vaccinated under real-life conditions are another way to document the persistence of protection. Finally, case-control studies in outbreak situations or in situations of persisting endemicity can also be used to document the persistence of the vaccine efficacy. All of these tools are used in the development of new vaccines, and also

Induction of protective immunity against toxoplasmosis in mice by immunization with Toxoplasma gondii RNA.

PubMed

Dimier-Poisson, Isabelle; Aline, Fleur; Bout, Daniel; Mévélec, Marie-Noëlle

2006-03-06

Toxoplasma gondii enters the mucosal surfaces of the host, and so immunity at these sites is of major interest. Due to the compartmentalization of the immune response, systemic immunization does not induce high levels of immunity at mucosal surfaces. Intranasal immunization has been shown to be very effective in inducing both systemic and mucosal immune responses. Immunization with mRNA can induce both humoral and cell-mediated immune responses, both of which are important in conferring immunity to T. gondii. The efficacy of RNA vaccination by the nasal route with T. gondii RNA was evaluated. We assessed the percentage of cumulative survival after an oral challenge with a lethal dose of T. gondii cysts (40 cysts), and the number of brain cysts following a challenge with a sublethal dose of T. gondii 76 K cysts (15 cysts). Vaccinated mice were found to be significantly better protected than non-immunized mice after a challenge with a lethal dose of cysts; and a challenge with a sublethal dose also resulted in fewer brain cysts than in non-immunized mice. Sera and intestinal secretions of immunized mice recognized T. gondii antigens, suggesting that a specific humoral immune response may occur. Moreover, a specific lymphoproliferative response observed in cervical lymph nodes may confer protection. These preliminary findings suggest that RNA vaccination by a mucosal route could be feasible.

Increased long-term immunity to Bacillus anthracis protective antigen in mice immunized with a CIA06B-adjuvanted anthrax vaccine.

PubMed

Wui, Seo Ri; Han, Ji Eun; Kim, Yeon Hee; Rhie, Gi-eun; Lee, Na Gyong

2013-04-01

Anthrax is an acute infectious disease caused by Bacillus anthracis. We previously reported that the adjuvant CIA06B, which consists of TLR4 agonist CIA05 and aluminum hydroxide (alum), enhanced the immune response to anthrax protective antigen (PA) in mice. This study was carried out to determine whether CIA06B can enhance long-term immune responses to PA in mice. BALB/c mice were immunized intramuscularly three times at 2-week intervals with recombinant PA alone or PA combined with alum or CIA06B. At 8 and 24 weeks post-immunization, the immunological responses including serum anti-PA IgG antibody titer, toxin-neutralizing antibody titer, splenic cytokine secretion and the frequency of PA-specific memory B cells were assessed. Compared with mice injected with PA alone or PA plus alum, mice injected with PA plus CIA06B had higher titers of serum anti-PA IgG antibodies, and higher frequencies of PA-specific memory B cells and interferon-γ secreting cells. Furthermore, anti-PA antibodies induced by CIA06B were more effective in neutralizing anthrax toxin. These results demonstrated that CIA06B is capable of providing long-term immunity when used as an adjuvant in a PA-based anthrax vaccine.

The ΔfbpA attenuated candidate vaccine from Mycobacterium tuberculosis, H37Rv primes for a stronger T-bet dependent Th1 immunity in mice.

PubMed

Roche, Cherie M; Smith, Amanda; Lindsey, Devin R; Meher, Akshay; Schluns, Kimberly; Arora, Ashish; Armitige, Lisa Y; Jagannath, Chinnaswamy

2011-12-01

The ΔfbpA candidate vaccine derived from Mycobacterium tuberculosis (H37Rv) (Mtb) protects mice better than BCG against tuberculosis, and we investigated the hypothesis that ΔfbpA may induce a stronger Th1 immunity. Since T-bet transcription factor regulates Th1 immunity, mice infected with ΔfbpA, BCG vaccine and related mycobacteria were analyzed for T-bet positive T cells. Mouse dendritic cells (DCs) or macrophages were also pulsed with excretory-secreted antigens (ES; Antigen-85B, ESAT-6 and CFP10) and cocultured with T cells from immunized or naïve mice and tested for in vitro induction of T-bet and IFN-γ. In both models, ΔfbpA mutant induced a stronger response of T-bet(+)CD4 T cells, which correlated with an increased expansion of IFN-γ(+)CD4 T cells in vivo and in vitro. When DCs pulsed with ES antigens were allowed to stimulate T cells, ESAT-6 and CFP-10 failed to induce a recall expansion of T-bet(+)IFN-γ(+)CD4 T cells from BCG vaccinated mice. Thus, deletion of RD1 in BCG seems to reduce its ability to induce T-bet and induce stronger Th1 immunity. Finally, mice were vaccinated with ΔfbpA and BCG and challenged with virulent Mtb for evaluation of protection and T cell expansion. ΔfbpA vaccinated mice showed a rapid and stronger expansion of CD4(+)CXCR3(+) IFN-γ(+) T cells in the lungs of Mtb challenged mice, compared to those which had BCG vaccine. ΔfbpA immunized mice also showed a better decline of the Mtb bacterial counts of the lungs. Mtb derived ΔfbpA candidate vaccine therefore induces qualitatively better T-bet dependent Th1 immunity than BCG vaccine. Copyright © 2011 Elsevier Ltd. All rights reserved.

Plant-made subunit vaccine against pneumonic and bubonic plague is orally immunogenic in mice.

PubMed

Alvarez, M Lucrecia; Pinyerd, Heidi L; Crisantes, Jason D; Rigano, M Manuela; Pinkhasov, Julia; Walmsley, Amanda M; Mason, Hugh S; Cardineau, Guy A

2006-03-24

Yersinia pestis, the causative agent of plague, is an extremely virulent bacterium but there are no approved vaccines for protection against it. Our goal was to produce a vaccine that would address: ease of delivery, mucosal efficacy, safety, rapid scalability, and cost. We developed a novel production and delivery system for a plague vaccine of a Y. pestis F1-V antigen fusion protein expressed in tomato. Immunogenicity of the F1-V transgenic tomatoes was confirmed in mice that were primed subcutaneously with bacterially-produced F1-V and boosted orally with transgenic tomato fruit. Expression of the plague antigens in fruit allowed producing an oral vaccine candidate without protein purification and with minimal processing technology.

Protection against bubonic and pneumonic plague with a single dose microencapsulated sub-unit vaccine.

PubMed

Elvin, Stephen J; Eyles, James E; Howard, Kenneth A; Ravichandran, Easwaran; Somavarappu, Satyanarayan; Alpar, H Oya; Williamson, E Diane

2006-05-15

Protection against virulent plague challenge by the parenteral and aerosol routes was afforded by a single administration of microencapsulated Caf1 and LcrV antigens from Yersinia pestis in BALB/c mice. Recombinant Caf1 and LcrV were individually encapsulated in polymeric microspheres, to the surface of which additional antigen was adsorbed. The microspheres containing either Caf1 or LcrV were blended and used to immunise mice on a single occasion, by either the intra-nasal or intra-muscular route. Both routes of immunisation induced systemic and local immune responses, with high levels of serum IgG being developed in response to both vaccine antigens. In Elispot assays, secretion of cytokines by spleen and draining lymph node cells was demonstrated, revealing activation of both Th1 and Th2 associated cytokines; and spleen cells from animals immunised by either route were found to proliferate in vitro in response to both vaccine antigens. Virulent challenge experiments demonstrated that non-invasive immunisation by intra-nasal instillation can provide strong systemic and local immune responses and protect against high level challenge. Microencapsulation of these vaccine antigens has the added advantage that controlled release of the antigens occurs in vivo, so that protective immunity can be induced after only a single immunising dose.

Novel Antigen Identification Method for Discovery of Protective Malaria Antigens by Rapid Testing of DNA Vaccines Encoding Exons from the Parasite Genome

PubMed Central

Haddad, Diana; Bilcikova, Erika; Witney, Adam A.; Carlton, Jane M.; White, Charles E.; Blair, Peter L.; Chattopadhyay, Rana; Russell, Joshua; Abot, Esteban; Charoenvit, Yupin; Aguiar, Joao C.; Carucci, Daniel J.; Weiss, Walter R.

2004-01-01

We describe a novel approach for identifying target antigens for preerythrocytic malaria vaccines. Our strategy is to rapidly test hundreds of DNA vaccines encoding exons from the Plasmodium yoelii yoelii genomic sequence. In this antigen identification method, we measure reduction in parasite burden in the liver after sporozoite challenge in mice. Orthologs of protective P. y. yoelii genes can then be identified in the genomic databases of Plasmodium falciparum and Plasmodium vivax and investigated as candidate antigens for a human vaccine. A pilot study to develop the antigen identification method approach used 192 P. y. yoelii exons from genes expressed during the sporozoite stage of the life cycle. A total of 182 (94%) exons were successfully cloned into a DNA immunization vector with the Gateway cloning technology. To assess immunization strategies, mice were vaccinated with 19 of the new DNA plasmids in addition to the well-characterized protective plasmid encoding P. y. yoelii circumsporozoite protein. Single plasmid immunization by gene gun identified a novel vaccine target antigen which decreased liver parasite burden by 95% and which has orthologs in P. vivax and P. knowlesi but not P. falciparum. Intramuscular injection of DNA plasmids produced a different pattern of protective responses from those seen with gene gun immunization. Intramuscular immunization with plasmid pools could reduce liver parasite burden in mice despite the fact that none of the plasmids was protective when given individually. We conclude that high-throughput cloning of exons into DNA vaccines and their screening is feasible and can rapidly identify new malaria vaccine candidate antigens. PMID:14977966

A Live Attenuated Equine H3N8 Influenza Vaccine Is Highly Immunogenic and Efficacious in Mice and Ferrets

PubMed Central

Baz, Mariana; Paskel, Myeisha; Matsuoka, Yumiko; Zengel, James; Cheng, Xing; Treanor, John J.; Jin, Hong

2014-01-01

ABSTRACT Equine influenza viruses (EIV) are responsible for rapidly spreading outbreaks of respiratory disease in horses. Although natural infections of humans with EIV have not been reported, experimental inoculation of humans with these viruses can lead to a productive infection and elicit a neutralizing antibody response. Moreover, EIV have crossed the species barrier to infect dogs, pigs, and camels and therefore may also pose a threat to humans. Based on serologic cross-reactivity of H3N8 EIV from different lineages and sublineages, A/equine/Georgia/1/1981 (eq/GA/81) was selected to produce a live attenuated candidate vaccine by reverse genetics with the hemagglutinin and neuraminidase genes of the eq/GA/81 wild-type (wt) virus and the six internal protein genes of the cold-adapted (ca) A/Ann Arbor/6/60 (H2N2) vaccine donor virus, which is the backbone of the licensed seasonal live attenuated influenza vaccine. In both mice and ferrets, intranasal administration of a single dose of the eq/GA/81 ca vaccine virus induced neutralizing antibodies and conferred complete protection from homologous wt virus challenge in the upper respiratory tract. One dose of the eq/GA/81 ca vaccine also induced neutralizing antibodies and conferred complete protection in mice and nearly complete protection in ferrets upon heterologous challenge with the H3N8 (eq/Newmarket/03) wt virus. These data support further evaluation of the eq/GA/81 ca vaccine in humans for use in the event of transmission of an equine H3N8 influenza virus to humans. IMPORTANCE Equine influenza viruses have crossed the species barrier to infect other mammals such as dogs, pigs, and camels and therefore may also pose a threat to humans. We believe that it is important to develop vaccines against equine influenza viruses in the event that an EIV evolves, adapts, and spreads in humans, causing disease. We generated a live attenuated H3N8 vaccine candidate and demonstrated that the vaccine was immunogenic and

A Bivalent Typhoid Live Vector Vaccine Expressing both Chromosome- and Plasmid-Encoded Yersinia pestis Antigens Fully Protects against Murine Lethal Pulmonary Plague Infection

PubMed Central

Wang, Jin Yuan; Carrasco, Jose A.; Lloyd, Scott A.; Mellado-Sanchez, Gabriela; Diaz-McNair, Jovita; Franco, Olga; Buskirk, Amanda D.; Nataro, James P.; Pasetti, Marcela F.

2014-01-01

Live attenuated bacteria hold great promise as multivalent mucosal vaccines against a variety of pathogens. A major challenge of this approach has been the successful delivery of sufficient amounts of vaccine antigens to adequately prime the immune system without overattenuating the live vaccine. Here we used a live attenuated Salmonella enterica serovar Typhi strain to create a bivalent mucosal plague vaccine that produces both the protective F1 capsular antigen of Yersinia pestis and the LcrV protein required for secretion of virulence effector proteins. To reduce the metabolic burden associated with the coexpression of F1 and LcrV within the live vector, we balanced expression of both antigens by combining plasmid-based expression of F1 with chromosomal expression of LcrV from three independent loci. The immunogenicity and protective efficacy of this novel vaccine were assessed in mice by using a heterologous prime-boost immunization strategy and compared to those of a conventional strain in which F1 and LcrV were expressed from a single low-copy-number plasmid. The serum antibody responses to lipopolysaccharide (LPS) induced by the optimized bivalent vaccine were indistinguishable from those elicited by the parent strain, suggesting an adequate immunogenic capacity maintained through preservation of bacterial fitness; in contrast, LPS titers were 10-fold lower in mice immunized with the conventional vaccine strain. Importantly, mice receiving the optimized bivalent vaccine were fully protected against lethal pulmonary challenge. These results demonstrate the feasibility of distributing foreign antigen expression across both chromosomal and plasmid locations within a single vaccine organism for induction of protective immunity. PMID:25332120

A complex adenovirus vaccine against chikungunya virus provides complete protection against viraemia and arthritis

PubMed Central

Wang, Danher; Suhrbier, Andreas; Penn-Nicholson, Adam; Woraratanadharm, Jan; Gardner, Joy; Luo, Min; Le, Thuy T.; Anraku, Itaru; Sakalian, Michael; Einfeld, David; Dong, John Y.

2011-01-01

Chikungunya virus, a mosquito-borne alphavirus, recently caused the largest epidemic ever seen for this virus. Chikungunya disease primarily manifests as a painful and debilitating arthralgia/arthritis, and no effective drug or vaccine is currently available. Here we describe a recombinant chikungunya virus vaccine comprising a non-replicating complex adenovirus vector encoding the structural polyprotein cassette of chikungunya virus. A single immunisation with this vaccine consistently induced high titres of anti-chikungunya virus antibodies that neutralised both an old Asian isolate and a Réunion Island isolate from the recent epidemic. The vaccine also completely protected mice against viraemia and arthritic disease caused by both virus isolates. PMID:21320541

Immunization of Mice with Formalin-Inactivated Spores from Avirulent Bacillus cereus Strains Provides Significant Protection from Challenge with Bacillus anthracis Ames

PubMed Central

Vergis, James M.; Cote, Christopher K.; Bozue, Joel; Alem, Farhang; Ventura, Christy L.; Welkos, Susan L.

2013-01-01

Bacillus anthracis spores are the infectious form of the organism for humans and animals. However, the approved human vaccine in the United States is derived from a vegetative culture filtrate of a toxigenic, nonencapsulated B. anthracis strain that primarily contains protective antigen (PA). Immunization of mice with purified spore proteins and formalin-inactivated spores (FIS) from a nonencapsulated, nontoxigenic B. anthracis strain confers protection against B. anthracis challenge when PA is also administered. To investigate the capacity of the spore particle to act as a vaccine without PA, we immunized mice subcutaneously with FIS from nontoxigenic, nonencapsulated B. cereus strain G9241 pBCXO1−/pBC210− (dcG9241), dcG9241 ΔbclA, or 569-UM20 or with exosporium isolated from dcG9241. FIS vaccination provided significant protection of mice from intraperitoneal or intranasal challenge with spores of the virulent B. anthracis Ames or Ames ΔbclA strain. Immunization with dcG9241 ΔbclA FIS, which are devoid of the immunodominant spore protein BclA, provided greater protection from challenge with either Ames strain than did immunization with FIS from BclA-producing strains. In addition, we used prechallenge immune antisera to probe a panel of recombinant B. anthracis Sterne spore proteins to identify novel immunogenic vaccine candidates. The antisera were variably reactive with BclA and with 10 other proteins, four of which were previously tested as vaccine candidates. Overall our data show that immunization with FIS from nontoxigenic, nonencapsulated B. cereus strains provides moderate to high levels of protection of mice from B. anthracis Ames challenge and that neither PA nor BclA is required for this protection. PMID:23114705

Immunogenicity and protective efficacy of yeast extracts containing rotavirus-like particles: a potential veterinary vaccine.

PubMed

Rodríguez-Limas, William A; Pastor, Ana Ruth; Esquivel-Soto, Ernesto; Esquivel-Guadarrama, Fernando; Ramírez, Octavio T; Palomares, Laura A

2014-05-19

Rotavirus is the most common cause of severe diarrhea in many animal species of economic interest. A simple, safe and cost-effective vaccine is required for the control and prevention of rotavirus in animals. In this study, we evaluated the use of Saccharomyces cerevisiae extracts containing rotavirus-like particles (RLP) as a vaccine candidate in an adult mice model. Two doses of 1mg of yeast extract containing rotavirus proteins (between 0.3 and 3 μg) resulted in an immunological response capable of reducing the replication of rotavirus after infection. Viral shedding in all mice groups diminished in comparison with the control group when challenged with 100 50% diarrhea doses (DD50) of murine rotavirus strain EDIM. Interestingly, when immunizing intranasally protection against rotavirus infection was observed even when no increase in rotavirus-specific antibody titers was evident, suggesting that cellular responses were responsible of protection. Our results indicate that raw yeast extracts containing rotavirus proteins and RLP are a simple, cost-effective alternative for veterinary vaccines against rotavirus. Copyright © 2014 Elsevier Ltd. All rights reserved.