Mucosal Luminal Manipulation of T Cell Geography Switches on Protective Efficacy by Otherwise Ineffective Parenteral Genetic Immunization

ABSTRACT 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 log10 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.

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Comparative Evaluation of T-Cell Immune Response to BTV Infection in Sheep Vaccinated with Pentavalent BTV Vaccine When Compared to Un-Vaccinated Animals

Veterinary Medicine International ◽

10.1155/2019/8762780 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Molalegne Bitew ◽

Chintu Ravishankar ◽

Soumendu Chakravarti ◽

Gaurav Kumar Sharma ◽

Sukdeb Nandi

Keyword(s):

Immune Response ◽

T Cells ◽

T Cell ◽

Protective Efficacy ◽

Cell Immune Response ◽

Respective Group ◽

Cytokine Induction ◽

Cell Mediated Immune Response ◽

Significant Difference ◽

The Mean

Recent invasion of multiple bluetongue virus serotypes (BTV) in different regions of the world necessitates urgent development of efficient vaccine that is directed against multiple BTV serotypes. In this experimental study, cell mediated immune response and protective efficacy of binary ethylenimine (BEI) inactivated Montanide™ ISA 206 adjuvanted pentavalent (BTV-1, 2, 10, 16 and 23) vaccine was evaluated in sheep and direct challenge with homologous BTV serotypes in their respective group. Significant (P<0.05) up-regulation of mRNA transcripts of IFN-α, IL-2, IL-6, IL-12, IFN-γ and TNF-α in PBMCs of vaccinated animals as compared to control (un-vaccinated) animals at certain time points was observed. On the other hand, there was a significant increase in mean ± SD percentage of CD8+ T cells after 7 days post challenge (DPC) but, the mean ± SD percentage of CD4+ T-cell population slightly declined at 7 DPC and enhanced after 14 DPC. Significant differences (P<0.05) of CD8+ and CD4+ T cells population was also observed between vaccinated and unvaccinated sheep. The vaccine also significantly (P<0.05) reduced BTV RNA load in PBMCs of vaccinated animals than unvaccinated animals following challenge. There were no significant difference (P>0.05) in cytokine induction, BTV RNA load and CD8+ and CD4+ cell count among BTV-1, 2, 10, 16 and 23 serotype challenges except significant increase in mean ± SD percentage of CD8+ in BTV-2 group. These findings put forwarded that binary ethylenimine inactivated montanide adjuvanted pentavalent bluetongue vaccine has stimulated cell mediated immune response and most importantly reduced the severity of BTV-1, 2, 10, 16 and 23 infections following challenge in respective group.

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Chimeric Yellow Fever/Dengue Virus as a Candidate Dengue Vaccine: Quantitation of the Dengue Virus-Specific CD8 T-Cell Response

Journal of Virology ◽

10.1128/jvi.74.17.8094-8101.2000 ◽

2000 ◽

Vol 74 (17) ◽

pp. 8094-8101 ◽

Cited By ~ 77

Author(s):

Robbert G. van der Most ◽

Kaja Murali-Krishna ◽

Rafi Ahmed ◽

James H. Strauss

Keyword(s):

T Cells ◽

T Cell ◽

Dengue Virus ◽

Yellow Fever ◽

Cd8 T Cells ◽

Cell Response ◽

Protective Efficacy ◽

Cd8 T Cell ◽

T Cell Response ◽

E Proteins

ABSTRACT We have constructed a chimeric yellow fever/dengue (YF/DEN) virus, which expresses the premembrane (prM) and envelope (E) genes from DEN type 2 (DEN-2) virus in a YF virus (YFV-17D) genetic background. Immunization of BALB/c mice with this chimeric virus induced a CD8 T-cell response specific for the DEN-2 virus prM and E proteins. This response protected YF/DEN virus-immunized mice against lethal dengue encephalitis. Control mice immunized with the parental YFV-17D were not protected against DEN-2 virus challenge, indicating that protection was mediated by the DEN-2 virus prM- and E-specific immune responses. YF/DEN vaccine-primed CD8 T cells expanded and were efficiently recruited into the central nervous systems of DEN-2 virus challenged mice. At 5 days after challenge, 3 to 4% of CD8 T cells in the spleen were specific for the prM and E proteins, and 34% of CD8 T cells in the central nervous system recognized these proteins. Depletion of either CD4 or CD8 T cells, or both, strongly reduced the protective efficacy of the YF/DEN virus, stressing the key role of the antiviral T-cell response.

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Genetic Immunization with Glycoprotein 63 cDNA Results in a Helper T Cell Type 1 Immune Response and Protection in a Murine Model of Leishmaniasis

Human Gene Therapy ◽

10.1089/hum.1998.9.13-1899 ◽

1998 ◽

Vol 9 (13) ◽

pp. 1899-1907 ◽

Cited By ~ 71

Author(s):

Patricia S. Walker ◽

Tanya Scharton-Kersten ◽

Edgar D. Rowton ◽

Ulrich Hengge ◽

Anne Bouloc ◽

...

Keyword(s):

Immune Response ◽

T Cell ◽

Murine Model ◽

Cell Type ◽

Genetic Immunization ◽

Helper T Cell

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Influences of Glycosylation on Antigenicity, Immunogenicity, and Protective Efficacy of Ebola Virus GP DNA Vaccines

Journal of Virology ◽

10.1128/jvi.02098-06 ◽

2006 ◽

Vol 81 (4) ◽

pp. 1821-1837 ◽

Cited By ~ 83

Author(s):

William Dowling ◽

Elizabeth Thompson ◽

Catherine Badger ◽

Jenny L. Mellquist ◽

Aura R. Garrison ◽

...

Keyword(s):

T Cell ◽

Protective Immunity ◽

Ebola Virus ◽

Dna Vaccines ◽

Protective Efficacy ◽

T Cell Epitopes ◽

Glycosylation Sites ◽

Membrane Bound ◽

Antibody Epitopes

ABSTRACT The Ebola virus (EBOV) envelope glycoprotein (GP) is the primary target of protective immunity. Mature GP consists of two disulfide-linked subunits, GP1 and membrane-bound GP2. GP is highly glycosylated with both N- and O-linked carbohydrates. We measured the influences of GP glycosylation on antigenicity, immunogenicity, and protection by testing DNA vaccines comprised of GP genes with deleted N-linked glycosylation sites or with deletions in the central hypervariable mucin region. We showed that mutation of one of the two N-linked GP2 glycosylation sites was highly detrimental to the antigenicity and immunogenicity of GP. Our data indicate that this is likely due to the inability of GP2 and GP1 to dimerize at the cell surface and suggest that glycosylation at this site is required for achieving the conformational integrity of GP2 and GP1. In contrast, mutation of two N-linked sites on GP1, which flank previously defined protective antibody epitopes on GP, may enhance immunogenicity, possibly by unmasking epitopes. We further showed that although deleting the mucin region apparently had no effect on antigenicity in vitro, it negatively impacted the elicitation of protective immunity in mice. In addition, we confirmed the presence of previously identified B-cell and T-cell epitopes in GP but show that when analyzed individually none of them were neither absolutely required nor sufficient for protective immunity to EBOV. Finally, we identified other potential regions of GP that may contain relevant antibody or T-cell epitopes.

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Induction of Specific T-Cell Responses, Opsonizing Antibodies, and Protection against Plasmodium chabaudi adami Infection in Mice Vaccinated with Genomic Expression Libraries Expressed in Targeted and Secretory DNA Vectors

Infection and Immunity ◽

10.1128/iai.71.8.4506-4515.2003 ◽

2003 ◽

Vol 71 (8) ◽

pp. 4506-4515 ◽

Cited By ~ 18

Author(s):

A. Rainczuk ◽

T. Scorza ◽

P. M. Smooker ◽

T. W. Spithill

Keyword(s):

T Cell ◽

Immune Responses ◽

Genomic Library ◽

Protective Efficacy ◽

T Cell Responses ◽

Interleukin 4 ◽

Plasmodium Chabaudi ◽

Lethal Challenge ◽

Cell Responses ◽

Expression Libraries

ABSTRACT It has been proposed that a multivalent malaria vaccine is necessary to mimic the naturally acquired resistance to this disease observed in humans. A major experimental challenge is to identify the optimal components to be used in such a multivalent vaccine. Expression library immunization (ELI) is a method for screening genomes of a pathogen to identify novel combinations of vaccine sequences. Here we describe immune responses associated with, and the protective efficacy of, genomic Plasmodium chabaudi adami DS expression libraries constructed in VR1020 (secretory), monocyte chemotactic protein-3 (chemoattractant), and cytotoxic T lymphocyte antigen 4 (lymph node-targeting) DNA vaccine vectors. With splenocytes from vaccinated mice, specific T-cell responses, as well as gamma interferon and interleukin-4 production, were observed after stimulation with P. chabaudi adami-infected erythrocytes, demonstrating the specificity of genomic library vaccination for two of the three libraries constructed. Sera obtained from mice vaccinated with genomic libraries promoted the opsonization of P. chabaudi adami-infected erythrocytes by murine macrophages in vitro, further demonstrating the induction of malaria-specific immune responses following ELI. Over three vaccine trials using biolistic delivery of the three libraries, protection after lethal challenge with P. chabaudi adami DS ranged from 33 to 50%. These results show that protective epitopes or antigens are expressed within the libraries and that ELI induces responses specific to P. chabaudi adami malaria. This study further demonstrates that ELI is a suitable approach for screening the malaria genome to identify the components of multivalent vaccines.

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CD8+-T-Cell-Dependent Control of Trypanosoma cruzi Infection in a Highly Susceptible Mouse Strain after Immunization with Recombinant Proteins Based on Amastigote Surface Protein 2

Infection and Immunity ◽

10.1128/iai.73.9.6017-6025.2005 ◽

2005 ◽

Vol 73 (9) ◽

pp. 6017-6025 ◽

Cited By ~ 44

Author(s):

Adriano F. S. Araújo ◽

Bruna C. G. de Alencar ◽

José Ronnie C. Vasconcelos ◽

Meire I. Hiyane ◽

Cláudio R. F. Marinho ◽

...

Keyword(s):

Amino Acids ◽

T Cells ◽

T Cell ◽

Recombinant Protein ◽

Trypanosoma Cruzi ◽

Recombinant Proteins ◽

Protective Immunity ◽

Protective Efficacy ◽

Surface Protein ◽

Cpg Oligodeoxynucleotide

ABSTRACT We previously described that DNA vaccination with the gene encoding amastigote surface protein 2 (ASP-2) protects approximately 65% of highly susceptible A/Sn mice against the lethal Trypanosoma cruzi infection. Here, we explored the possibility that bacterial recombinant proteins of ASP-2 could be used to improve the efficacy of vaccinations. Initially, we compared the protective efficacy of vaccination regimens using either a plasmid DNA, a recombinant protein, or both sequentially (DNA priming and protein boosting). Survival after the challenge was not statistically different among the three mouse groups and ranged from 53.5 to 75%. The fact that immunization with a recombinant protein alone induced protective immunity revealed the possibility that this strategy could be pursued for vaccination. We investigated this possibility by using six different recombinant proteins representing distinct portions of ASP-2. The vaccination of mice with glutathione S-transferase fusion proteins representing amino acids 261 to 500 or 261 to 380 of ASP-2 in the presence of the adjuvants alum and CpG oligodeoxynucleotide 1826 provided remarkable immunity, consistently protecting 100% of the A/Sn mice. Immunity was completely reversed by the in vivo depletion of CD8+ T cells, but not CD4+ T cells, and was associated with the presence of CD8+ T cells specific for an epitope located between amino acids 320 and 327 of ASP-2. We concluded that a relatively simple formulation consisting of a recombinant protein with a selected portion of ASP-2, alum, and CpG oligodeoxynucleotide 1826 might be used to cross-prime strong CD8+-T-cell-dependent protective immunity against T. cruzi infection.

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A lipidated peptide of Mycobacterium tuberculosis resuscitates the protective efficacy of BCG vaccine by evoking memory T cell immunity

Journal of Translational Medicine ◽

10.1186/s12967-017-1301-x ◽

2017 ◽

Vol 15 (1) ◽

Cited By ~ 6

Author(s):

Pradeep K. Rai ◽

Sathi Babu Chodisetti ◽

Weiguang Zeng ◽

Sajid Nadeem ◽

Sudeep K. Maurya ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

T Cell ◽

Protective Efficacy ◽

T Cell Immunity ◽

Bcg Vaccine ◽

Memory T Cell ◽

Cell Immunity

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Preexisting Inflammation Due to Mycobacterium bovis BCG Infection Differentially Modulates T-Cell Priming against a Replicating or Nonreplicating Immunogen

Infection and Immunity ◽

10.1128/iai.70.4.1957-1964.2002 ◽

2002 ◽

Vol 70 (4) ◽

pp. 1957-1964 ◽

Cited By ~ 15

Author(s):

Renu Dudani ◽

Yvan Chapdelaine ◽

Henk van Faassen ◽

Dean K. Smith ◽

Hao Shen ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Mycobacterium Bovis ◽

Inflammatory Responses ◽

Protective Efficacy ◽

T Cell Response ◽

Boost Vaccine ◽

Ifn Γ ◽

T Cell Priming

ABSTRACT Induction of T-cell memory by vaccination ensures long-term protection against pathogens. We determined whether on-going inflammatory responses during vaccination influenced T-cell priming. A preexposure of mice to Mycobacterium bovis BCG impaired their subsequent ability to prime T cells against Listeria monocytogenes. This was characterized by a decrease in L. monocytogenes-specific gamma interferon (IFN-γ)-secreting CD4+ and CD8+ T cells. The intensity of T-cell priming towards L. monocytogenes depended on the extent of L. monocytogenes expansion, and a cessation of this expansion caused by M. bovis BCG-induced inflammation resulted in impairment in T-cell priming. A challenge of M. bovis BCG-infected mice with a higher L. monocytogenes dose increased L. monocytogenes survival and restored T-cell priming towards L. monocytogenes. Impairment in T-cell priming towards L. monocytogenes due to M. bovis BCG-induced inflammation resulted in a compromised protective efficacy in the long term after mice were rechallenged with L. monocytogenes. Preexisting inflammation selectively impaired T-cell priming for replicating immunogens as CD8+ T-cell response to ovalbumin administered as an inert antigen (ovalbumin-archaeosomes) was enhanced by M. bovis BCG preimmunization, whereas priming towards ovalbumin administered as a live immunogen (L. monocytogenes-ovalbumin) was impaired. Thus, depending on the nature of the immunogen, the presence of prior inflammatory responses may either impede or boost vaccine efficacy.

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