title: Successful in vitro priming of EBV-specific CD8+ T cells endowed with strong cytotoxic function from T cells of EBV-seronegative children.
abstract: Epstein-Barr virus (EBV)-seronegative transplant recipients are at high risk of developing EBV-associated post-transplant lymphoproliferative disorder (PTLD), and would maximally benefit from an EBV-directed T-cell therapy for prevention or treatment of PTLD. So far, efforts to activate CD8+ EBV-specific cytotoxic T lymphocytes (CTL) endowed with high specific cytotoxicity from EBV-seronegative children have failed. We compared the CD8+ CTL priming efficiency of three different modified activation protocols, based on lymphoblastoid cell lines (LCL) stimulation potentially enhanced by either LCL presentation through dendritic cells, or selection of IFN-gamma+ cultured cells, or culture in the presence of rhIL-12 and rhIL-7, according to the standard protocol for reactivation of EBV-specific CTL. We found that only specific LCL stimulation in the presence of rhIL-12 and rhIL-7 was able to reproducibly expand EBV-specific CD8+ CTL endowed with strong cytotoxic activity from truly EBV-seronegative children. The lines thus activated, which included specificities toward EBV latent and lytic proteins, showed high percentage CD8+ T cells, with <10% naïve CD8+/CCR7+/CD45RA+ cells. Overall, the total number of CD8+ central memory cells, and of CCR7 T-cell effectors was comparable to that observed in healthy EBV-seropositive controls. In conclusion, it is feasible to activate EBV-specific CD8+ CTL with suitable characteristics for in vivo employment from EBV-seronegative children.
authors.affiliation: Laboratory of Transplant Immunology and Pediatric Hematology/Oncology, IRCCS Policlinico S. Matteo, 27100 Pavia, Italy. pcomoli@smatteo.pv.it
authors.forename: P
authors.initials: P
authors.lastname: Comoli
authors.forename: F
authors.initials: F
authors.lastname: Ginevri
authors.forename: R
authors.initials: R
authors.lastname: Maccario
authors.forename: C
authors.initials: C
authors.lastname: Frasson
authors.forename: U
authors.initials: U
authors.lastname: Valente
authors.forename: S
authors.initials: S
authors.lastname: Basso
authors.forename: M
authors.initials: M
authors.lastname: Labirio
authors.forename: G-C
authors.initials: GC
authors.lastname: Huang
authors.forename: E
authors.initials: E
authors.lastname: Verrina
authors.forename: F
authors.initials: F
authors.lastname: Baldanti
authors.forename: F
authors.initials: F
authors.lastname: Perfumo
authors.forename: F
authors.initials: F
authors.lastname: Locatelli
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D016026:Bone Marrow Transplantation / Q000009:adverse effects*; D018414:CD8-Positive T-Lymphocytes / Q000821:virology*; D002648:Child; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism; D005260:Female; D004854:Herpesvirus 4, Human / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D018664:Interleukin-12 / Q000494:pharmacology; D015851:Interleukin-7 / Q000494:pharmacology; D007963:Leukocytes, Mononuclear / Q000821:virology; D008232:Lymphoproliferative Disorders / Q000209:etiology; D008297:Male; D010641:Phenotype; D011994:Recombinant Proteins / Q000494:pharmacology; D013602:T-Lymphocytes, Cytotoxic / Q000821:virology*
chemical_list: D000914:Antibodies, Viral; D015851:Interleukin-7; D011994:Recombinant Proteins; D018664:Interleukin-12; D007371:Interferon-gamma