title: Standardized and highly efficient expansion of Epstein-Barr virus-specific CD4+ T cells by using virus-like particles.
abstract: Epstein-Barr virus (EBV)-specific T-cell lines generated by repeated stimulation with EBV-immortalized lymphoblastoid B-cell lines (LCL) have been successfully used to treat EBV-associated posttransplant lymphoproliferative disease (PTLD) in hematopoietic stem cell transplant recipients. However, PTLD in solid-organ transplant recipients and other EBV-associated malignancies respond less efficiently to this adoptive T-cell therapy. LCL-stimulated T-cell preparations are polyclonal and contain CD4(+) and CD8(+) T cells, but the composition varies greatly between lines. Because T-cell lines with higher CD4(+) T-cell proportions show improved clinical efficacy, we assessed which factors might compromise the expansion of this T-cell population. Here we show that spontaneous virus production by LCL and, hence, the presentation of viral antigens varies intra- and interindividually and is further impaired by acyclovir treatment of LCL. Moreover, the stimulation of T cells with LCL grown in medium supplemented with fetal calf serum (FCS) caused the expansion of FCS-reactive CD4(+) T cells, whereas human serum from EBV-seropositive donors diminished viral antigen presentation. To overcome these limitations, we used peripheral blood mononuclear cells pulsed with nontransforming virus-like particles as antigen-presenting cells. This strategy facilitated the specific and rapid expansion of EBV-specific CD4(+) T cells and, thus, might contribute to the development of standardized protocols for the generation of T-cell lines with improved clinical efficacy.
authors.affiliation: Children's Hospital, University of Technology, Kölner Platz 1, D-80804 Munich, Germany.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Adhikary
authors.forename: Uta
authors.initials: U
authors.lastname: Behrends
authors.forename: Regina
authors.initials: R
authors.lastname: Feederle
authors.forename: Henri-Jacques
authors.initials: HJ
authors.lastname: Delecluse
authors.forename: Josef
authors.initials: J
authors.lastname: Mautner
mesh_terms: D000212:Acyclovir / Q000494:pharmacology; D017951:Antigen Presentation / Q000187:drug effects / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D049109:Cell Proliferation; D002478:Cells, Cultured; D004854:Herpesvirus 4, Human / Q000276:immunology*; D006801:Humans; D007155:Immunologic Factors / Q000494:pharmacology; D007963:Leukocytes, Mononuclear / Q000276:immunology; D022701:Virosomes / Q000276:immunology*
chemical_list: D007155:Immunologic Factors; D022701:Virosomes; D000212:Acyclovir