title: Characterization of antigen-specific repertoire diversity following in vitro restimulation by a recombinant adenovirus expressing human cytomegalovirus pp65.
abstract: Human cytomegalovirus (HCMV) and adenovirus cause significant morbidity and mortality in immunocompromised hosts undergoing allogeneic stem cell transplantation. We have previously established a procedure for the generation of polyclonal CTL with specificity against adenovirus and HCMV using a recombinant adenovirus encoding the HCMV pp65 protein (RAdpp65). However, specific CTL expanded after in vitro culture steps were subjected to several in vitro restimulations and, depending on the protocol adopted, this could lead to a selection bias, compromising the clinical benefit. To determine which part of the memory repertoire is selected after in vitro restimulation, we have followed the specificity and clonal composition of pp65-peptide-specific CD8(+) T cells in HLA-A*201 individuals before and after repeated in vitro restimulation of cells with RAdpp65, combining HLA tetrameric complexes and immunoscope analysis. Tetramer staining showed that, after in vitro restimulation, up to 60% of CD8(+) T cells were virus-specific. Immunoscope analysis showed that the predominant TCRBV diversity of pp65-specific clones was conserved, demonstrating that the memory repertoire was preserved all along the procedure. Altogether, these results suggest that the use of RAdpp65 to induce CMV- and adenovirus-specific CTL maybe appropriate for immunotherapy.
authors.affiliation: INSERM U429, Hôpital Necker-Enfants Malades, 149 rue de Sèvres, F-75743 Paris Cedex 15, France.
authors.forename: Yamina
authors.initials: Y
authors.lastname: Hamel
authors.forename: Pierre
authors.initials: P
authors.lastname: Rohrlich
authors.forename: Véronique
authors.initials: V
authors.lastname: Baron
authors.forename: Delphine
authors.initials: D
authors.lastname: Bonhomme
authors.forename: Frederic
authors.initials: F
authors.lastname: Rieux-Laucat
authors.forename: Antje
authors.initials: A
authors.lastname: Necker
authors.forename: François
authors.initials: F
authors.lastname: Lemonnier
authors.forename: Laurent
authors.initials: L
authors.lastname: Ferradini
authors.forename: Alain
authors.initials: A
authors.lastname: Fischer
authors.forename: Marina
authors.initials: M
authors.lastname: Cavazzana-Calvo
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000956:Antigens, Viral / Q000276:immunology*; D002460:Cell Line; D022801:Complementarity Determining Regions; D003602:Cytotoxicity, Immunologic; D015234:HLA-A Antigens / Q000276:immunology; D006801:Humans; D007156:Immunologic Memory; D010750:Phosphoproteins / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014763:Viral Matrix Proteins / Q000276:immunology*
chemical_list: D000956:Antigens, Viral; D022801:Complementarity Determining Regions; D015234:HLA-A Antigens; D010750:Phosphoproteins; D011994:Recombinant Proteins; D014763:Viral Matrix Proteins; C065418:cytomegalovirus matrix protein 65kDa