Strategy for eliciting antigen-specific CD8+ T cell-mediated immune response against a cryptic CTL epitope of merkel cell polyomavirus large T antigen

<p>Abstract</p> <p>Background</p> <p>Merkel cell carcinoma (MCC) is a relatively new addition to the expanding category of oncovirus-induced cancers. Although still comparably rare, the number of cases has risen dramatically in recent years. Further complicating this tr...

Full description

Bibliographic Details
Main Authors: Gomez Bianca P, Wang Connie, Viscidi Raphael P, Peng Shiwen, He Liangmei, Wu T-C, Hung Chien-Fu
Format: Article
Language:English
Published: BMC 2012-10-01
Series:Cell & Bioscience
Subjects:
Online Access:http://www.cellandbioscience.com/content/2/1/36
_version_ 1811315404433260544
author Gomez Bianca P
Wang Connie
Viscidi Raphael P
Peng Shiwen
He Liangmei
Wu T-C
Hung Chien-Fu
author_facet Gomez Bianca P
Wang Connie
Viscidi Raphael P
Peng Shiwen
He Liangmei
Wu T-C
Hung Chien-Fu
author_sort Gomez Bianca P
collection DOAJ
description <p>Abstract</p> <p>Background</p> <p>Merkel cell carcinoma (MCC) is a relatively new addition to the expanding category of oncovirus-induced cancers. Although still comparably rare, the number of cases has risen dramatically in recent years. Further complicating this trend is that MCC is an extremely aggressive neoplasm with poor patient prognosis and limited treatment options for advanced disease. The causative agent of MCC has been identified as the merkel cell polyomavirus (MCPyV). The MCPyV-encoded large T (LT) antigen is an oncoprotein that is theorized to be essential for virus-mediated tumorigenesis and is therefore, an excellent MCC antigen for the generation of antitumor immune responses. As a foreign antigen, the LT oncoprotein avoids the obstacle of immune tolerance, which normally impedes the development of antitumor immunity. Ergo, it is an excellent target for anti-MCC immunotherapy. Since tumor-specific CD8+ T cells lead to better prognosis for MCC and numerous other cancers, we have generated a DNA vaccine that is capable of eliciting LT-specific CD8+ T cells. The DNA vaccine (pcDNA3-CRT/LT) encodes the LT antigen linked to a damage-associated molecular pattern, calreticulin (CRT), as it has been demonstrated that the linkage of CRT to antigens promotes the induction of antigen-specific CD8+ T cells.</p> <p>Results</p> <p>The present study shows that DNA vaccine-induced generation of LT-specific CD8+ T cells is augmented by linking CRT to the LT antigen. This is relevant since the therapeutic effects of the pcDNA3-CRT/LT DNA vaccine is mediated by LT-specific CD8+ T cells. Mice vaccinated with the DNA vaccine produced demonstrably more LT-specific CD8+ T cells. The DNA vaccine was also able to confer LT-specific CD8+ T cell-mediated protective and therapeutic effects to prolong the survival of mice with LT-expressing tumors. In the interest of determining the LT epitope which most MCC-specific CD8+ T cells recognize, we identified the amino acid sequence of the immunodominant LT epitope as aa19-27 (IAPNCYGNI) and found that it is H-2k<sup>b</sup>-restricted.</p> <p>Conclusion</p> <p>The results of this study can facilitate the development of other modes of MCC treatment such as peptide-based vaccines and adoptive transfer of LT-specific CD8+ T cells. Likewise, the MCC DNA vaccine has great potential for clinical translation as the immunologic specificity is high and the treatment strategy can be exported to address other virus-induced tumors.</p>
first_indexed 2024-04-13T11:29:31Z
format Article
id doaj.art-6796f7480ce3469ca3af3d8d0511ea83
institution Directory Open Access Journal
issn 2045-3701
language English
last_indexed 2024-04-13T11:29:31Z
publishDate 2012-10-01
publisher BMC
record_format Article
series Cell & Bioscience
spelling doaj.art-6796f7480ce3469ca3af3d8d0511ea832022-12-22T02:48:36ZengBMCCell & Bioscience2045-37012012-10-01213610.1186/2045-3701-2-36Strategy for eliciting antigen-specific CD8+ T cell-mediated immune response against a cryptic CTL epitope of merkel cell polyomavirus large T antigenGomez Bianca PWang ConnieViscidi Raphael PPeng ShiwenHe LiangmeiWu T-CHung Chien-Fu<p>Abstract</p> <p>Background</p> <p>Merkel cell carcinoma (MCC) is a relatively new addition to the expanding category of oncovirus-induced cancers. Although still comparably rare, the number of cases has risen dramatically in recent years. Further complicating this trend is that MCC is an extremely aggressive neoplasm with poor patient prognosis and limited treatment options for advanced disease. The causative agent of MCC has been identified as the merkel cell polyomavirus (MCPyV). The MCPyV-encoded large T (LT) antigen is an oncoprotein that is theorized to be essential for virus-mediated tumorigenesis and is therefore, an excellent MCC antigen for the generation of antitumor immune responses. As a foreign antigen, the LT oncoprotein avoids the obstacle of immune tolerance, which normally impedes the development of antitumor immunity. Ergo, it is an excellent target for anti-MCC immunotherapy. Since tumor-specific CD8+ T cells lead to better prognosis for MCC and numerous other cancers, we have generated a DNA vaccine that is capable of eliciting LT-specific CD8+ T cells. The DNA vaccine (pcDNA3-CRT/LT) encodes the LT antigen linked to a damage-associated molecular pattern, calreticulin (CRT), as it has been demonstrated that the linkage of CRT to antigens promotes the induction of antigen-specific CD8+ T cells.</p> <p>Results</p> <p>The present study shows that DNA vaccine-induced generation of LT-specific CD8+ T cells is augmented by linking CRT to the LT antigen. This is relevant since the therapeutic effects of the pcDNA3-CRT/LT DNA vaccine is mediated by LT-specific CD8+ T cells. Mice vaccinated with the DNA vaccine produced demonstrably more LT-specific CD8+ T cells. The DNA vaccine was also able to confer LT-specific CD8+ T cell-mediated protective and therapeutic effects to prolong the survival of mice with LT-expressing tumors. In the interest of determining the LT epitope which most MCC-specific CD8+ T cells recognize, we identified the amino acid sequence of the immunodominant LT epitope as aa19-27 (IAPNCYGNI) and found that it is H-2k<sup>b</sup>-restricted.</p> <p>Conclusion</p> <p>The results of this study can facilitate the development of other modes of MCC treatment such as peptide-based vaccines and adoptive transfer of LT-specific CD8+ T cells. Likewise, the MCC DNA vaccine has great potential for clinical translation as the immunologic specificity is high and the treatment strategy can be exported to address other virus-induced tumors.</p>http://www.cellandbioscience.com/content/2/1/36DNA vaccineGene therapyMerkel cell polyomavirusCryptic CTL EpitopeLarge T antigen
spellingShingle Gomez Bianca P
Wang Connie
Viscidi Raphael P
Peng Shiwen
He Liangmei
Wu T-C
Hung Chien-Fu
Strategy for eliciting antigen-specific CD8+ T cell-mediated immune response against a cryptic CTL epitope of merkel cell polyomavirus large T antigen
Cell & Bioscience
DNA vaccine
Gene therapy
Merkel cell polyomavirus
Cryptic CTL Epitope
Large T antigen
title Strategy for eliciting antigen-specific CD8+ T cell-mediated immune response against a cryptic CTL epitope of merkel cell polyomavirus large T antigen
title_full Strategy for eliciting antigen-specific CD8+ T cell-mediated immune response against a cryptic CTL epitope of merkel cell polyomavirus large T antigen
title_fullStr Strategy for eliciting antigen-specific CD8+ T cell-mediated immune response against a cryptic CTL epitope of merkel cell polyomavirus large T antigen
title_full_unstemmed Strategy for eliciting antigen-specific CD8+ T cell-mediated immune response against a cryptic CTL epitope of merkel cell polyomavirus large T antigen
title_short Strategy for eliciting antigen-specific CD8+ T cell-mediated immune response against a cryptic CTL epitope of merkel cell polyomavirus large T antigen
title_sort strategy for eliciting antigen specific cd8 t cell mediated immune response against a cryptic ctl epitope of merkel cell polyomavirus large t antigen
topic DNA vaccine
Gene therapy
Merkel cell polyomavirus
Cryptic CTL Epitope
Large T antigen
url http://www.cellandbioscience.com/content/2/1/36
work_keys_str_mv AT gomezbiancap strategyforelicitingantigenspecificcd8tcellmediatedimmuneresponseagainstacrypticctlepitopeofmerkelcellpolyomaviruslargetantigen
AT wangconnie strategyforelicitingantigenspecificcd8tcellmediatedimmuneresponseagainstacrypticctlepitopeofmerkelcellpolyomaviruslargetantigen
AT viscidiraphaelp strategyforelicitingantigenspecificcd8tcellmediatedimmuneresponseagainstacrypticctlepitopeofmerkelcellpolyomaviruslargetantigen
AT pengshiwen strategyforelicitingantigenspecificcd8tcellmediatedimmuneresponseagainstacrypticctlepitopeofmerkelcellpolyomaviruslargetantigen
AT heliangmei strategyforelicitingantigenspecificcd8tcellmediatedimmuneresponseagainstacrypticctlepitopeofmerkelcellpolyomaviruslargetantigen
AT wutc strategyforelicitingantigenspecificcd8tcellmediatedimmuneresponseagainstacrypticctlepitopeofmerkelcellpolyomaviruslargetantigen
AT hungchienfu strategyforelicitingantigenspecificcd8tcellmediatedimmuneresponseagainstacrypticctlepitopeofmerkelcellpolyomaviruslargetantigen