VennVax, a DNA-prime, peptide-boost multi-T-cell epitope poxvirus vaccine, induces protective immunity against vaccinia infection by T cell response alone

Understanding the mechanisms and impact of booster vaccinations can facilitate decisions on vaccination programmes. This study shows that three doses of the same synthetic peptide vaccine eliciting an exclusive CD8+ T cell response against one SARS-CoV-2 Spike epitope protected all mice against lethal SARS-CoV-2 infection in the K18-hACE2 transgenic mouse model in the absence of neutralizing antibodies, while only a second vaccination with this T cell vaccine was insufficient to provide protection. The third vaccine dose of the single T cell epitope peptide resulted in superior generation of effector-memory T cells in the circulation and tissue-resident memory T (TRM) cells, and these tertiary vaccine-specific CD8+ T cells were characterized by enhanced polyfunctional cytokine production. Moreover, fate mapping showed that a substantial fraction of the tertiary effector-memory CD8+ T cells developed from remigrated TRM cells. Thus, repeated booster vaccinations quantitatively and qualitatively improve the CD8+ T cell response leading to protection against otherwise lethal SARS-CoV-2 infection.

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Characterization of T-cell response to woodchuck hepatitis virus core protein and protection of woodchucks from infection by immunization with peptides containing a T-cell epitope.

Journal of Virology ◽

10.1128/jvi.71.1.65-74.1997 ◽

1997 ◽

Vol 71 (1) ◽

pp. 65-74 ◽

Cited By ~ 67

Author(s):

S Menne ◽

J Maschke ◽

T K Tolle ◽

M Lu ◽

M Roggendorf

Keyword(s):

T Cell ◽

Cell Response ◽

Core Protein ◽

Hepatitis Virus ◽

Cell Epitope ◽

T Cell Response ◽

Woodchuck Hepatitis Virus ◽

T Cell Epitope ◽

Virus Core

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Listeria Monocytogenes: A Model Pathogen Continues to Refine Our Knowledge of the CD8 T Cell Response

Pathogens ◽

10.3390/pathogens7020055 ◽

2018 ◽

Vol 7 (2) ◽

pp. 55 ◽

Cited By ~ 11

Author(s):

Zhijuan Qiu ◽

Camille Khairallah ◽

Brian Sheridan

Keyword(s):

Listeria Monocytogenes ◽

T Cell ◽

Cell Response ◽

Protective Immunity ◽

T Cell Responses ◽

Cd8 T Cell ◽

Oral Infection ◽

T Cell Response ◽

Infection Model ◽

Cell Responses

Listeria monocytogenes (Lm) infection induces robust CD8 T cell responses, which play a critical role in resolving Lm during primary infection and provide protective immunity to re-infections. Comprehensive studies have been conducted to delineate the CD8 T cell response after Lm infection. In this review, the generation of the CD8 T cell response to Lm infection will be discussed. The role of dendritic cell subsets in acquiring and presenting Lm antigens to CD8 T cells and the events that occur during T cell priming and activation will be addressed. CD8 T cell expansion, differentiation and contraction as well as the signals that regulate these processes during Lm infection will be explored. Finally, the formation of memory CD8 T cell subsets in the circulation and in the intestine will be analyzed. Recently, the study of CD8 T cell responses to Lm infection has begun to shift focus from the intravenous infection model to a natural oral infection model as the humanized mouse and murinized Lm have become readily available. Recent findings in the generation of CD8 T cell responses to oral infection using murinized Lm will be explored throughout the review. Finally, CD8 T cell-mediated protective immunity against Lm infection and the use of Lm as a vaccine vector for cancer immunotherapy will be highlighted. Overall, this review will provide detailed knowledge on the biology of CD8 T cell responses after Lm infection that may shed light on improving rational vaccine design.

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AChlamydia trachomatisStrain Expressing Ovalbumin Stimulates an Antigen-Specific CD4+T Cell Response in Mice

Infection and Immunity ◽

10.1128/iai.00837-18 ◽

2019 ◽

Vol 87 (7) ◽

Author(s):

Jennifer D. Helble ◽

Michael N. Starnbach

Keyword(s):

T Cells ◽

T Cell ◽

Cell Response ◽

Fluorescent Protein ◽

Genetic Manipulation ◽

Cell Epitope ◽

T Cell Response ◽

Developmental Cycle ◽

Dependent Manner ◽

Content Type

ABSTRACTAntigen-specific CD4+T cells againstChlamydiaare crucial for driving bacterial clearance and mediating protection against reinfection. Although theChlamydia trachomatisprotein Cta1 has been identified to be a dominant murine CD4+T cell antigen, its level of expression during the bacterial developmental cycle and precise localization within the host cell are unknown. Newly developed tools forChlamydiagenetic manipulation have allowed us to generate aC. trachomatisstrain expressing a heterologous CD4+T cell epitope from ovalbumin (OVA) consisting of OVA residues 323 to 339 (OVA323–339). By tagging proteins expressed inC. trachomatiswith OVA323–339, we can begin to understand how protein expression, developmental regulation, and subcellular compartmentalization affect the potential of those proteins to serve as antigens. When OVA323–339was expressed as a fusion with green fluorescent protein, we found that we were able to elicit an OT-II T cell response in an antigen-dependent manner, but surprisingly, these T cells were unable to reduce bacterial burden in mice. These data suggest that the subcellular localization of antigen, the level of antigen expression, or the timing of expression within the developmental cycle ofChlamydiamay play a crucial role in eliciting a protective CD4+T cell response.

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