CMV pp65 and IE-1 T cell epitopes recognized by healthy subjects

Slezak, Stefanie; Bettinotti, María P.; Selleri, Silvia; Adams, Sharon; Marincola, Francesco M.; Stroncek, David F.

doi:10.1186/1479-5876-5-17

Cited by 60 publications

(60 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It is known that pp65 is one of the major targets of the cellular immune response (16,17,23,24,49,59,61), and a long-term GBM survivor who underwent autologous dendritic cell vaccination was also found to mount a strong CD8 ϩ T-cell response to a pp65 immunodominant epitope (42). To assess both nucleotide and amino acid variability across the major pp65 epitope-producing domains, a 970-bp region of UL83 coding for amino acids 273 to 561 of pp65 was amplified and sequenced from seven tumor specimens that produced an amplification product (Table 2).…”

Section: Resultsmentioning

confidence: 99%

Genetic Analysis of Cytomegalovirus in Malignant Gliomas

Bhattacharjee

Renzette

Kowalik

2012

J Virol

View full text Add to dashboard Cite

Human cytomegalovirus (HCMV) has been found in malignant gliomas at variable frequencies with efforts to date focused on characterizing the role(s) of single gene products in disease. Here, we reexamined the HCMV prevalence in malignant gliomas using different methods and began to dissect the genetics of HCMV in tumors. HCMV DNA was found in 16/17 (94%) tumor specimens. Viral DNA copy numbers were found to be low and variable, ranging from 10 2 to 10 6 copies/500 ng of total DNA. The tumor tissues had incongruences between viral DNA copy numbers and protein levels. However, nonlatent protein expression was detected in many tumors. The viral UL83 gene, encoding pp65, was found to segregate into five cancer-associated genotypes with a bias for amino acid changes in glioblastoma multiforme (GBM) in comparison to the low-grade tumors. Deep sequencing of a GBM-associated viral population resulted in 81,224 bp of genome coverage. Sequence analysis revealed the presence of intact open reading frames and higher numbers of high-frequency variations within the repeat long region compared to the unique long region, which harbors many core genes, and the unique short region ( P = 0.001). This observation was in congruence with phylogenetic analyses across replication-competent viral strains in databases. The tumor-associated viral population was less variable (π = 0.1% and π AA = 0.08%) than that observed in other clinical infections. Moreover, 42/46 (91.3%) viral genes analyzed had dN/dS scores of <1, which is indicative of high amino acid sequence conservation. Taken together, these findings raise the possibility that replication-competent HCMV may exist in malignant gliomas.

show abstract

Section: Resultsmentioning

confidence: 99%

Genetic Analysis of Cytomegalovirus in Malignant Gliomas

Bhattacharjee

Renzette

Kowalik

2012

J Virol

View full text Add to dashboard Cite

show abstract

“…Following reactivation of varicella-zoster virus, high frequencies of circulating T cells recognizing a variety of structural and regulatory proteins were found (22,23). Strong CD8 ϩ T cell responses to the tegument phosphoprotein 65 and the immediate early protein 1 were found for the ␤-herpesvirus human CMV (24,25). In healthy carriers of the ␥-herpesvirus EBV, a considerable proportion of the peripheral T cell repertoire is directed against EBV-encoded Ags, predominantly derived from latent and immediate early viral proteins (26).…”

Section: Ajor Histocompatibility Complex Class I-mediated Peptide Pmentioning

confidence: 96%

The Varicellovirus UL49.5 Protein Blocks the Transporter Associated with Antigen Processing (TAP) by Inhibiting Essential Conformational Transitions in the 6+6 Transmembrane TAP Core Complex

Verweij

Koppers-Lalić

Loch

et al. 2008

The Journal of Immunology

View full text Add to dashboard Cite

TAP translocates virus-derived peptides from the cytosol into the endoplasmic reticulum, where the peptides are loaded onto MHC class I molecules. This process is crucial for the detection of virus-infected cells by CTL that recognize the MHC class I-peptide complexes at the cell surface. The varicellovirus bovine herpesvirus 1 encodes a protein, UL49.5, that acts as a potent inhibitor of TAP. UL49.5 acts in two ways, as follows: 1) by blocking conformational changes of TAP required for the translocation of peptides into the endoplasmic reticulum, and 2) by targeting TAP1 and TAP2 for proteasomal degradation. At present, it is unknown whether UL49.5 interacts with TAP1, TAP2, or both. The contribution of other members of the peptide-loading complex has not been established. Using TAP-deficient cells reconstituted with wild-type and recombinant forms of TAP1 and TAP2, TAP was defined as the prime target of UL49.5 within the peptide-loading complex. The presence of TAP1 and TAP2 was required for efficient interaction with UL49.5. Using deletion mutants of TAP1 and TAP2, the 6+6 transmembrane core complex of TAP was shown to be sufficient for UL49.5 to interact with TAP and block its function. However, UL49.5-induced inhibition of peptide transport was most efficient in cells expressing full-length TAP1 and TAP2. Inhibition of TAP by UL49.5 appeared to be independent of the presence of other peptide-loading complex components, including tapasin. These results demonstrate that UL49.5 acts directly on the 6+6 transmembrane TAP core complex of TAP by blocking essential conformational transitions required for peptide transport.

show abstract

“…To generate constructs BϩD18 and 108A/233D/AC Ϫ (Table 1), the immunodominant epitopes of the human cytomegalovirus (CMV) phosphoprotein 65 (pp65) (46,52) were assembled into one polyepitope polypeptide (Table 1), and the corresponding codon-optimized synthetic open reading frame was purchased from GenScript (Piscataway, NJ).…”

Section: Methodsmentioning

confidence: 99%

“…It was next important to establish the polyepitope delivery and CD8 ϩ CTL-priming capacity of the ⌬AC toxoids in a clinically relevant system. To this end, advantage was taken of the facts that 50 to 85% of healthy adults are latently infected with cytomegalovirus (CMV) and that several strong and highly conserved CD8 ϩ CTL epitopes of the pp65 phosphoprotein of CMV have been identified (46,52). Moreover, efficient tools for ex vivo expansion of CMV-specific CD8 ϩ cytotoxic T lymphocytes exhibit a clear clinical potential for use in the treatment of CMV disease in recipients of bone marrow transplants (15,43).…”

Section: Figmentioning

confidence: 99%

Delivery of Large Heterologous Polypeptides across the Cytoplasmic Membrane of Antigen-Presenting Cells by the Bordetella RTX Hemolysin Moiety Lacking the Adenylyl Cyclase Domain

et al. 2012

View full text Add to dashboard Cite

The Bordetella adenylate cyclase toxin-hemolysin (CyaA; also called ACT or AC-Hly) targets CD11b-expressing phagocytes and translocates into their cytosol an adenylyl cyclase (AC) that hijacks cellular signaling by conversion of ATP to cyclic AMP (cAMP). Intriguingly, insertion of large passenger peptides removes the enzymatic activity but not the cell-invasive capacity of the AC domain. This has repeatedly been exploited for delivery of heterologous antigens into the cytosolic pathway of CD11b-expressing dendritic cells by CyaA/AC ؊ toxoids, thus enabling their processing and presentation on major histocompatibility complex (MHC) class I molecules to cytotoxic CD8 ؉ T lymphocytes (CTLs). We produced a set of toxoids with overlapping deletions within the first 371 residues of CyaA and showed that the structure of the AC enzyme does not contain any sequences indispensable for its translocation across target cell membrane. Moreover, replacement of the AC domain (residues 1 to 371) with heterologous polypeptides of 40, 146, or 203 residues yielded CyaA⌬AC constructs that delivered passenger CTL epitopes into antigen-presenting cells (APCs) and induced strong antigen-specific CD8؉ CTL responses in vivo in mice and ex vivo in human peripheral blood mononuclear cell cultures. This shows that the RTX (repeats in toxin) hemolysin moiety, consisting of residues 374 to 1706 of CyaA, harbors all structural information involved in translocation of the N-terminal AC domain across target cell membranes. These results decipher the extraordinary capacity of the AC domain of CyaA to transport large heterologous cargo polypeptides into the cytosol of CD11b ؉ target cells and pave the way for the construction of CyaA⌬AC-based polyvalent immunotherapeutic T cell vaccines.

show abstract

CMV pp65 and IE-1 T cell epitopes recognized by healthy subjects

Abstract: Background: Adoptive immune and vaccine therapies have been used to prevent cytomegalovirus (CMV) disease in recipients of hematopoietic progenitor cell transplants, but the nature of T cell responses to CMV have not been completely characterized.

Cited by 60 publications

References 28 publications

Genetic Analysis of Cytomegalovirus in Malignant Gliomas

Genetic Analysis of Cytomegalovirus in Malignant Gliomas

The Varicellovirus UL49.5 Protein Blocks the Transporter Associated with Antigen Processing (TAP) by Inhibiting Essential Conformational Transitions in the 6+6 Transmembrane TAP Core Complex

Delivery of Large Heterologous Polypeptides across the Cytoplasmic Membrane of Antigen-Presenting Cells by the Bordetella RTX Hemolysin Moiety Lacking the Adenylyl Cyclase Domain

Contact Info

Product

Resources

About