Identification and Characterization of Dominant Helper T-Cell Epitopes in the Nucleocapsid Protein of Severe Acute Respiratory Syndrome Coronavirus

ABSTRACT By using a series of overlapping synthetic peptides covering 98% of the amino acid sequence of the nucleocapsid protein (NP) of severe acute respiratory syndrome coronavirus (SARS-CoV), four helper T-cell (Th) epitopes (NP11, residues 11 to 25; NP51, residues 51 to 65; NP61, residues 61 to 75; and NP111, residues 111 to 125) in C57BL mice (H-2b), four (NP21, residues 21 to 35; NP91, residues 91 to 105; NP331, residues 331 to 345; and NP351, residues 351 to 365) in C3H mice (H-2k), and two (NP81, residues 81 to 95; and NP351, residues 351 to 365) in BALB/c mice (H-2d) have been identified. All of these peptides were able to stimulate the proliferation of NP-specific T-cell lines or freshly isolated lymph node cells from mice immunized with recombinant NP. Immunization of mice with synthetic peptides containing appropriate Th epitopes elicited strong cellular immunity in vivo, as evidenced by delayed-type hypersensitivity. Priming with the helper peptides (e.g., NP111 and NP351) significantly accelerated the immune response induced by recombinant NP, as determined by the production of NP-specific antibodies. When fused with a conserved neutralizing epitope (SP1143-1157) from the spike protein of SARS-CoV, NP111 and NP351 assisted in the production of high-titer neutralizing antibodies in vivo. These data provide useful insights regarding immunity against SARS-CoV and have the potential to help guide the design of peptide-based vaccines.

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In Vitro and In Vivo Studies for Assessing the Immune Response and Protection-Inducing Ability Conferred by Fasciola hepatica-Derived Synthetic Peptides Containing B- and T-Cell Epitopes

PLoS ONE ◽

10.1371/journal.pone.0105323 ◽

2014 ◽

Vol 9 (8) ◽

pp. e105323 ◽

Cited By ~ 22

Author(s):

Jose Rojas-Caraballo ◽

Julio López-Abán ◽

Luis Pérez del Villar ◽

Carolina Vizcaíno ◽

Belén Vicente ◽

...

Keyword(s):

Immune Response ◽

T Cell ◽

Synthetic Peptides ◽

Fasciola Hepatica ◽

In Vivo Studies ◽

T Cell Epitopes

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Clonal dissection of immunodominance and cross-reactivity of the CD4+ T cell response to SARS-CoV-2

10.1101/2021.03.23.436642 ◽

2021 ◽

Author(s):

Jun Siong Low ◽

Daniela Vaqueirinho ◽

Federico Mele ◽

Mathilde Foglierini ◽

Michela Perotti ◽

...

Keyword(s):

T Cell ◽

Cell Response ◽

Neutralizing Antibodies ◽

Cross Reactivity ◽

T Cell Response ◽

T Cell Epitopes ◽

Hla Dr ◽

Cell Clones

AbstractThe identification of CD4+ T cell epitopes is essential for the design of effective vaccines capable of inducing neutralizing antibodies and long-term immunity. Here we demonstrate in COVID-19 patients a robust CD4+ T cell response to naturally processed SARS-CoV-2 Spike and Nucleoprotein, including effector, helper and memory T cells. By characterizing 2,943 Spike-reactive T cell clones, we found that 34% of the clones and 93% of the patients recognized a conserved immunodominant region encompassing residues S346-365 in the RBD and comprising three nested HLA-DR and HLA-DP restricted epitopes. By using pre- and post-COVID-19 samples and Spike proteins from alpha and beta coronaviruses, we provide in vivo evidence of cross-reactive T cell responses targeting multiple sites in the SARS-CoV-2 Spike protein. The possibility of leveraging immunodominant and cross-reactive T helper epitopes is instrumental for vaccination strategies that can be rapidly adapted to counteract emerging SARS-CoV-2 variants.

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Mapping of murine Th1 and Th2 helper T-cell epitopes on fimbriae from Porphyromonas gingivalis

Journal of Medical Microbiology ◽

10.1099/00222615-42-3-165 ◽

1995 ◽

Vol 42 (3) ◽

pp. 165-170 ◽

Cited By ~ 8

Author(s):

T. Ogawa ◽

H. Uchida ◽

K. Yasuda

Keyword(s):

T Cell ◽

Porphyromonas Gingivalis ◽

T Cell Epitopes ◽

Helper T Cell ◽

Th1 And Th2

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H-2 restriction of virus-specific T-cell-mediated effector functions in vivo. II. Adoptive transfer of delayed-type hypersensitivity to murine lymphocytic choriomeningits virus is restriced by the K and D region of H-2.

Journal of Experimental Medicine ◽

10.1084/jem.144.3.776 ◽

1976 ◽

Vol 144 (3) ◽

pp. 776-787 ◽

Cited By ~ 83

Author(s):

R M Zinkernagel

Keyword(s):

T Cells ◽

T Cell ◽

Adoptive Transfer ◽

Gamma Globulin ◽

Effector T Cells ◽

Delayed Type Hypersensitivity ◽

T Effector Cells ◽

Immune Lymphocytes ◽

D Region

In mice, primary footpad swelling after local infection with lymphocytic choriomeningitis virus (LCMV) and delayed-type hypersensitivity (DTH) adoptively transferred by LCMV immune lymphocytes are T-cell dependent. Nude mice do not develop primary footpad swelling, and T-cell depletion abrogates the capacity to transfer LCMV-specific DTH. Effector T cells involved in eliciting dose-dependent DTH are virus specific in that vaccinia virus-immune lymphocytes could not elicit DTH in LCMV-infected mice. The adoptive transfer of DTH is restricted to H-2K or H-2D compatible donor-recipient combinations. Distinct from the fowl-gamma-globulin DTH model, I-region compatibility is neither necessary nor alone sufficient. Whatever the mechanisms involved in this K- or D-region associated restriction in vivo, it most likely operates at the level of T-cell recognition of "altered self" coded in K or D. T cells associated with the I region (helper T cells and DTH-T cells to fowl-gamma-globulin) are specific for soluble, defined, and inert antigens. T cells associated with the K and D region (T cells cytotoxic in vitro and in vivo for acute LCMV-infected cells, DTH effector T cells, and anti-viral T cells) are specific for infectious, multiplying virus. The fact that T-cell specificity is differentially linked with the I region or with the K and D regions of H-2 may reflect the fundamental biological differences of these antigens. Although it cannot be excluded that separate functional subclasses of T-effector cells could have self-recognizers for different cell surface structures coded in I or K and D, it is more likely that the antigen parameters determine whether T cells are specific for "altered" I or "altered" K- or D-coded structures.

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Optimized Adenovirus-Antibody Complexes Stimulate Strong Cellular and Humoral Immune Responses against an Encoded Antigen in Naïve Mice and Those with Preexisting Immunity

Clinical and Vaccine Immunology ◽

10.1128/cvi.05319-11 ◽

2011 ◽

Vol 19 (1) ◽

pp. 84-95 ◽

Cited By ~ 6

Author(s):

Jin Huk Choi ◽

Joe Dekker ◽

Stephen C. Schafer ◽

Jobby John ◽

Craig E. Whitfill ◽

...

Keyword(s):

Immune Response ◽

T Cell ◽

Immune Responses ◽

Neutralizing Antibodies ◽

T Cell Responses ◽

Transduction Efficiency ◽

Virus Antibody ◽

Cell Responses

ABSTRACTThe immune response to recombinant adenoviruses is the most significant impediment to their clinical use for immunization. We test the hypothesis that specific virus-antibody combinations dictate the type of immune response generated against the adenovirus and its transgene cassette under certain physiological conditions while minimizing vector-induced toxicity.In vitroandin vivoassays were used to characterize the transduction efficiency, the T and B cell responses to the encoded transgene, and the toxicity of 1 × 1011adenovirus particles mixed with different concentrations of neutralizing antibodies. Complexes formed at concentrations of 500 to 0.05 times the 50% neutralizing dose (ND50) elicited strong virus- and transgene-specific T cell responses. The 0.05-ND50formulation elicited measurable anti-transgene antibodies that were similar to those of virus alone (P= 0.07). This preparation also elicited very strong transgene-specific memory T cell responses (28.6 ± 5.2% proliferation versus 7.7 ± 1.4% for virus alone). Preexisting immunity significantly reduced all responses elicited by these formulations. Although lower concentrations (0.005 and 0.0005 ND50) of antibody did not improve cellular and humoral responses in naïve animals, they did promote strong cellular (0.005 ND50) and humoral (0.0005 ND50) responses in mice with preexisting immunity. Some virus-antibody complexes may improve the potency of adenovirus-based vaccines in naïve individuals, while others can sway the immune response in those with preexisting immunity. Additional studies with these and other virus-antibody ratios may be useful to predict and model the type of immune responses generated against a transgene in those with different levels of exposure to adenovirus.

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Murine monoclonal antibodies against RBD of SARS-CoV-2 neutralize authentic wild type SARS-CoV-2 as well as B.1.1.7 and B.1.351 viruses and protect in vivo in a mouse model in a neutralization dependent manner

10.1101/2021.04.05.438547 ◽

2021 ◽

Author(s):

Fatima Amanat ◽

Shirin Strohmeier ◽

Wen-Hsin Lee ◽

Sandhya Bangaru ◽

Andrew B Ward ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Severe Acute Respiratory Syndrome ◽

Mouse Model ◽

Neutralizing Antibodies ◽

Dependent Manner ◽

Receptor Binding Domain ◽

Wild Type ◽

Murine Monoclonal Antibodies

After first emerging in December 2019 in China, severe acute respiratory syndrome 2 (SARS-CoV-2) has since caused a pandemic leading to millions of infections and deaths worldwide. Vaccines have been developed and authorized but supply of these vaccines is currently limited. With new variants of the virus now emerging and spreading globally, it is essential to develop therapeutics that are broadly protective and bind conserved epitopes in the receptor binding domain (RBD) or the whole spike of SARS-CoV-2. In this study, we have generated mouse monoclonal antibodies (mAbs) against different epitopes on the RBD and assessed binding and neutralization against authentic SARS-CoV-2. We have demonstrated that antibodies with neutralizing activity, but not non-neutralizing antibodies, lower viral titers in the lungs when administered in a prophylactic setting in vivo in a mouse challenge model. In addition, most of the mAbs cross-neutralize the B.1.351 as well as the B.1.1.7 variants in vitro.

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Mapping of the immunodominant B- and T-cell epitopes of the outer membrane protein P6 of H. influenzae type b using overlapping synthetic peptides

Peptides ◽

10.1007/978-94-011-0683-2_241 ◽

1994 ◽

pp. 730-731

Author(s):

P. Chong ◽

O. James ◽

Y.-P. Yang ◽

C. Sia ◽

B. Tripet ◽

...

Keyword(s):

T Cell ◽

Membrane Protein ◽

Outer Membrane ◽

Outer Membrane Protein ◽

Synthetic Peptides ◽

T Cell Epitopes ◽

Type B

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Mapping of T cell epitopes using recombinant antigens and synthetic peptides.

The EMBO Journal ◽

10.1002/j.1460-2075.1987.tb02360.x ◽

1987 ◽

Vol 6 (5) ◽

pp. 1245-1249 ◽

Cited By ~ 99

Author(s):

J. R. Lamb ◽

J. Ivanyi ◽

A. D. Rees ◽

J. B. Rothbard ◽

K. Howland ◽

...

Keyword(s):

T Cell ◽

Synthetic Peptides ◽

T Cell Epitopes ◽

Recombinant Antigens

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Irradiated B7-1 transduced primary acute myelogenous leukemia (AML) cells can be used as therapeutic vaccines in murine AML

Blood ◽

10.1182/blood.v87.7.2938.bloodjournal8772938 ◽

1996 ◽

Vol 87 (7) ◽

pp. 2938-2946 ◽

Cited By ~ 73

Author(s):

K Dunussi-Joannopoulos ◽

HJ Weinstein ◽

PW Nickerson ◽

TB Strom ◽

SJ Burakoff ◽

...

Keyword(s):

T Cell ◽

Acute Myelogenous Leukemia ◽

High Titer ◽

Myelogenous Leukemia ◽

Therapeutic Vaccines ◽

Natural Ligand ◽

Acute Myelogenous ◽

High Level ◽

Transformed Cell Lines

Recent studies have shown that tumor cells genetically modified by transduction of B7–1, a natural ligand for the T-cell costimulatory molecules CD28 and CTLA-4, are rejected in syngeneic hosts. In these reports, transformed cell lines and drug-selected cells have been used for vaccinations. To determine the effectiveness of B7–1-transduced primary acute myelogenous leukemia (AML) cells on the induction of antitumor immunity, we have studied a murine AML model in which primary AML cells were retrovirally transduced with the murine B7–1 cDNA. A defective retroviral producer clone expressing B7–1 and secreting a high titer of virus was used for infection of AML cells. Unselected transduced AML cells, expressing a high level of B7–1, were used for in vivo vaccinations. Our results show that one intravenous (IV) injection of irradiated B7–1-positive (B7–1+) AML cells can provide long-lasting (5 to 6 months) systemic immunity against subsequent challenge with wild-type AML cells. Furthermore, one exposure to irradiated B7–1+ AML cells results in rejection of leukemia by leukemic mice when the vaccination occurs in the early stages of the disease. The antileukemia immunity is CD8+ T-cell-dependent and B7/CD28-mediated, since in vivo treatment of mice with anti-CD8 monoclonal antibody or CTLA-4 Ig leads to abrogation of the specific antileukemia immune response. These results emphasize that B7–1 vaccines may have therapeutic usefulness for patients with AML.

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