title: Partial protection against SIV challenge by vaccination of adenovirus and MVA vectors in rhesus monkeys.
abstract: This study explores the effect of priming rhesus monkeys with an Ad5/35 vector expressing simian immunodeficiency virus (SIV) gag and gp120, and then boosting the animals with an modified vaccinia virus Ankara (MVA) vector encoding the same antigens after a 2-month interval. The animals were intravenously challenged with 100 TCID50 of highly pathogenic SIVmac239 virus 2 months after the booster vaccination. The priming vaccination induced robust SIV-specific cell-mediated and humoral immune responses, and boosting further enhanced the cellular immunity. Vaccination reduced peak and long-term viral loads by 1-2 logs for a period of >6 months, as reflected by a reduction in both the SIV RNA and DNA levels. Of considerable interest, the immunized monkeys did not suffer from loss of CD4 T cells, particularly central memory CD4 T cells. These results demonstrate that prophylactic vaccination with Ad5/35 followed by MVA reduces viral replication and prevents CD4 T-cell loss, and that these effects may decrease the likelihood of disease progression.
authors.affiliation: Hisun Pharmaceutical Co. Ltd, Zhejiang, China.
authors.forename: H-B
authors.initials: HB
authors.lastname: Wang
authors.forename: A
authors.initials: A
authors.lastname: Kondo
authors.forename: A
authors.initials: A
authors.lastname: Yoshida
authors.forename: S
authors.initials: S
authors.lastname: Yoshizaki
authors.forename: S
authors.initials: S
authors.lastname: Abe
authors.forename: L-L
authors.initials: LL
authors.lastname: Bao
authors.forename: N
authors.initials: N
authors.lastname: Mizuki
authors.forename: M
authors.initials: M
authors.lastname: Ichino
authors.forename: D
authors.initials: D
authors.lastname: Klinman
authors.forename: K
authors.initials: K
authors.lastname: Okuda
authors.forename: M
authors.initials: M
authors.lastname: Shimada
mesh_terms: D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D015750:Genes, gag; D005822:Genetic Vectors; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D007115:Immunization Schedule; D007117:Immunization, Secondary; D008253:Macaca mulatta; D008562:Membrane Glycoproteins / Q000235:genetics; D018449:SAIDS Vaccines / Q000276:immunology / Q000627:therapeutic use*; D016097:Simian Acquired Immunodeficiency Syndrome / Q000517:prevention & control*; D013601:T-Lymphocytes / Q000276:immunology; D014616:Vaccinia virus / Q000235:genetics*; D014759:Viral Envelope Proteins / Q000235:genetics; D019562:Viral Load
chemical_list: D008562:Membrane Glycoproteins; D018449:SAIDS Vaccines; D014759:Viral Envelope Proteins; C069623:gp120 protein, Simian immunodeficiency virus