title: Attenuated poxviruses generate clinically relevant frequencies of CMV-specific T cells.
abstract: Immunotherapeutic approaches to limit cytomegalovirus (CMV) morbidity and mortality after hematopoietic stem cell transplants (HSCTs) are currently under investigation as alternatives to antiviral drugs. In this context, we have inserted full-length and ubiquitin-modified CMV phosphoprotein 65 (pp65), phosphoprotein 150 (pp150), and immediate early protein 1 (IE1) immunodominant antigens into the virulent Western Reserve strain of vaccinia virus (VV) and the highly attenuated strain, modified vaccinia Ankara (MVA). Recombinant (r) VV or rMVA stimulated vigorous expansion of CMV-specific CD8+ T cells in CMV-positive donor peripheral blood mononuclear cells (PBMCs), which showed minimal alloreactivity and high levels of HLA tetramer binding, cytokine production, and cytotoxicity. Ubiquitinated antigens had a profound effect when expressed in VV. Single antigen rMVA expressing pp65 or IE1, either ubiquitin-modified or native, stimulated both cytotoxic T lymphocyte (CTL) populations to be expanded up to 500-fold in a 60-mL blood draw from the same donor. This result demonstrates the clinical feasibility of simultaneously amplifying multiple CMV-CTL populations. Transgenic HLA A2.1 (HHD II) mice, immunized with the same rMVA as used with human PBMCs, produced a robust cytotoxic response to both CMV pp65 and IE1. The specificity of the vigorous immunologic response to rMVA, both in vitro and in vivo, makes them candidates for clinical evaluation in the context of adoptive immunotherapy for hematopoietic stem cell transplant (HSCT) recipients or donor vaccination.
authors.affiliation: Laboratory of Vaccine Research, Beckman Research Institute of the City of Hope,City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA.
authors.forename: Zhongde
authors.initials: Z
authors.lastname: Wang
authors.forename: Corinna
authors.initials: C
authors.lastname: La Rosa
authors.forename: Shahram
authors.initials: S
authors.lastname: Mekhoubad
authors.forename: Simon F
authors.initials: SF
authors.lastname: Lacey
authors.forename: Maria C
authors.initials: MC
authors.lastname: Villacres
authors.forename: Susan
authors.initials: S
authors.lastname: Markel
authors.forename: Jeff
authors.initials: J
authors.lastname: Longmate
authors.forename: Joshua D I
authors.initials: JD
authors.lastname: Ellenhorn
authors.forename: Robert F
authors.initials: RF
authors.lastname: Siliciano
authors.forename: Christopher
authors.initials: C
authors.lastname: Buck
authors.forename: William J
authors.initials: WJ
authors.lastname: Britt
authors.forename: Don J
authors.initials: DJ
authors.lastname: Diamond
mesh_terms: D001483:Base Sequence; D003587:Cytomegalovirus / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000209:etiology / Q000276:immunology / Q000401:mortality; D017931:DNA Primers; D006801:Humans; D010750:Phosphoproteins / Q000276:immunology; D033581:Stem Cell Transplantation / Q000009:adverse effects*; D013601:T-Lymphocytes / Q000276:immunology* / Q000821:virology; D014613:Vaccines, Attenuated; D014616:Vaccinia virus / Q000276:immunology*; D014763:Viral Matrix Proteins / Q000276:immunology; D014765:Viral Vaccines
chemical_list: D017931:DNA Primers; D010750:Phosphoproteins; D014613:Vaccines, Attenuated; D014763:Viral Matrix Proteins; D014765:Viral Vaccines; C065418:cytomegalovirus matrix protein 65kDa