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Subdominant CD8 T-cell epitopes account for protection against cytomegalovirus independent of immunodomination.

ABSTRACT: Cytomegalovirus (CMV) infection continues to be a complication in recipients of hematopoietic stem cell transplantation (HSCT). Preexisting donor immunity is recognized as a favorable prognostic factor for the reconstitution of protective antiviral immunity mediated primarily by CD8 T cells. Furthermore, adoptive transfer of CMV-specific memory CD8 T (CD8-T(M)) cells is a therapeutic option for preventing CMV disease in HSCT recipients. Given the different CMV infection histories of donor and recipient, a problem may arise from an antigenic mismatch between the CMV variant that has primed donor immunity and the CMV variant acquired by the recipient. Here, we have used the BALB/c mouse model of CMV infection in the immunocompromised host to evaluate the importance of donor-recipient CMV matching in immundominant epitopes (IDEs). For this, we generated the murine CMV (mCMV) recombinant virus mCMV-DeltaIDE, in which the two memory repertoire IDEs, the IE1-derived peptide 168-YPHFMPTNL-176 presented by the major histocompatibility complex class I (MHC-I) molecule L(d) and the m164-derived peptide 257-AGPPRYSRI-265 presented by the MHC-I molecule D(d), are both functionally deleted. Upon adoptive transfer, polyclonal donor CD8-T(M) cells primed by mCMV-DeltaIDE and the corresponding revertant virus mCMV-revDeltaIDE controlled infection of immunocompromised recipients with comparable efficacy and regardless of whether or not IDEs were presented in the recipients. Importantly, CD8-T(M) cells primed under conditions of immunodomination by IDEs protected recipients in which IDEs were absent. This shows that protection does not depend on compensatory expansion of non-IDE-specific CD8-T(M) cells liberated from immunodomination by the deletion of IDEs. We conclude that protection is, rather, based on the collective antiviral potential of non-IDEs independent of the presence or absence of IDE-mediated immunodomination.

SUBMITTER: Holtappels R

PROVIDER: S-EPMC2395166 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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Subdominant CD8 T-cell epitopes account for protection against cytomegalovirus independent of immunodomination.

Holtappels Rafaela R Simon Christian O CO Munks Michael W MW Thomas Doris D Deegen Petra P Kühnapfel Birgit B Däubner Torsten T Emde Simone F SF Podlech Jürgen J Grzimek Natascha K A NK Oehrlein-Karpi Silke A SA Hill Ann B AB Reddehase Matthias J MJ

Journal of virology 20080326 12

Cytomegalovirus (CMV) infection continues to be a complication in recipients of hematopoietic stem cell transplantation (HSCT). Preexisting donor immunity is recognized as a favorable prognostic factor for the reconstitution of protective antiviral immunity mediated primarily by CD8 T cells. Furthermore, adoptive transfer of CMV-specific memory CD8 T (CD8-T(M)) cells is a therapeutic option for preventing CMV disease in HSCT recipients. Given the different CMV infection histories of donor and re ...[more]

PMID: 18367531

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Subdominant CD8 T-cell epitopes account for protection against cytomegalovirus independent of immunodomination.

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Subdominant CD8 T-cell epitopes account for protection against cytomegalovirus independent of immunodomination.

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