GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    In: Journal of Virology, American Society for Microbiology, Vol. 80, No. 21 ( 2006-11), p. 10436-10456
    Abstract: During murine cytomegalovirus (mCMV) latency in the lungs, most of the viral genomes are transcriptionally silent at the major immediate-early locus, but rare and stochastic episodes of desilencing lead to the expression of IE1 transcripts. This low-frequency but perpetual expression is accompanied by an activation of lung-resident effector-memory CD8 T cells specific for the antigenic peptide 168-YPHFMPTNL-176, which is derivedfrom the IE1 protein. These molecular and immunological findings were combined in the “silencing/desilencing and immune sensing hypothesis” of cytomegalovirus latency and reactivation. This hypothesis proposes that IE1 gene expression proceeds to cell surface presentation of the IE1 peptide by the major histocompatibility complex (MHC) class I molecule L d and that its recognition by CD8 T cells terminates virus reactivation. Here we provide experimental evidence in support of this hypothesis. We generated mutant virus mCMV-IE1-L176A, in which the antigenic IE1 peptide is functionally deleted by a point mutation of the C-terminal MHC class I anchor residue Leu into Ala. Two revertant viruses, mCMV-IE1-A176L and the wobble nucleotide-marked mCMV-IE1-A176L*, in which Leu is restored by back-mutation of Ala codon GCA into Leu codons CTA and CTT, respectively, were constructed. Pulmonary latency of the mutant virus was found to be associated with an increased prevalence of IE1 transcription and with events of IE3 transactivator splicing. In conclusion, IE1-specific CD8 T cells recognize and terminate virus reactivation in vivo at the first opportunity in the reactivated gene expression program. The perpetual gene expression and antigen presentation might represent the driving molecular force in CMV-associated immunosenescence.
    Type of Medium: Online Resource
    ISSN: 0022-538X , 1098-5514
    Language: English
    Publisher: American Society for Microbiology
    Publication Date: 2006
    detail.hit.zdb_id: 1495529-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Online Resource
    Online Resource
    American Society for Microbiology ; 2007
    In:  Journal of Virology Vol. 81, No. 14 ( 2007-07-15), p. 7805-7810
    In: Journal of Virology, American Society for Microbiology, Vol. 81, No. 14 ( 2007-07-15), p. 7805-7810
    Abstract: Enhancers are defined as DNA elements that increase transcription when placed in any orientation relative to a promoter. The major immediate-early (MIE) enhancer region of murine cytomegalovirus is flanked by transcription units ie1/3 and ie2 , which are transcribed in opposite directions. We have addressed the fundamental mechanistic question of whether the enhancer synchronizes transcription of the bidirectional gene pair (synchronizer model) or whether it operates as a genetic switch, enhancing transcription of either gene in a stochastic alternation (switch model). Clonal analysis of cytokine-triggered, transcription factor-mediated MIE gene expression from latent viral genomes provided evidence in support of the switch model.
    Type of Medium: Online Resource
    ISSN: 0022-538X , 1098-5514
    Language: English
    Publisher: American Society for Microbiology
    Publication Date: 2007
    detail.hit.zdb_id: 1495529-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Journal of Virology, American Society for Microbiology, Vol. 82, No. 12 ( 2008-06-15), p. 5781-5796
    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-ΔIDE, 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-ΔIDE and the corresponding revertant virus mCMV-revΔIDE 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.
    Type of Medium: Online Resource
    ISSN: 0022-538X , 1098-5514
    Language: English
    Publisher: American Society for Microbiology
    Publication Date: 2008
    detail.hit.zdb_id: 1495529-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...