Heterologous prime/boost immunizations of rhesus monkeys using chimpanzee adenovirus vectors

Division of Viral Pathogenesis, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Vaccine (Impact Factor: 3.49). 09/2009; 27(42):5837-45. DOI: 10.1016/j.vaccine.2009.07.050
Source: PubMed

ABSTRACT Pre-existing immunity to human adenovirus serotype 5 (AdHu5) has been shown to suppress the immunogenicity of recombinant Ad5 (rAdHu5) vector-based vaccines for human immunodeficiency virus type 1 (HIV-1) in both preclinical studies and clinical trials. As a potential solution to this problem we developed adenovirus vaccine vectors of chimpanzee origin. In the present study we assessed the immunogenicity of various chimpanzee adenovirus vectors in a prime/boost regimen to HIV-1 envelope and SIV Gag-Pol in rhesus monkeys and their ability to protect against pathogenic viral challenge. Although rAdHu5-primed monkeys had higher magnitude T cell responses than rAdC7 or rAdC68 prior to challenge, the rAdC7-rAdC1/C5 and rAdHu5-rAdC1/C5 immunizations resulted in comparable magnitude recall cellular immune responses and comparable level of control of viremia post-challenge.

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Available from: Birgit Korioth-Schmitz, Jun 17, 2015
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