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Chimpanzee adenoviral vector prime-boost regimen elicits potent immune responses against Ebola virus in mice and rhesus macaques.

ABSTRACT: In the last few decades, Ebola virus (EBOV) has emerged periodically and infected people in Africa, resulting in an extremely high mortality rate. With no available prophylaxis or cure so far, a highly effective Ebola vaccine is urgently needed. In this study, we developed a novel chimpanzee adenovirus-based prime-boost vaccine by exploiting two recombinant replication-deficient chimpanzee adenoviral vectors, AdC7 and AdC68, which express glycoproteins (GP) of the EBOV strain identified in the 2014 outbreak. Our results indicated that a single immunization using AdC7 or AdC68 could stimulate potent EBOV-specific antibody responses, whereas the AdC7 prime-AdC68 boost regimen induced much stronger and sustained humoral and cellular immune responses in both mice and rhesus monkeys, compared with AdC7 or AdC68 single vaccination or the AdC68 prime-AdC7 boost regimen. This prime-boost vaccine could also protect mice from the simulated infection with EBOV-like particle (EBOVLP) in biosafety level 2 (BSL-2) laboratories, and antibodies from the prime-boost immunized rhesus macaques could passively provide protection against EBOVLP infection. Altogether, our results show that the AdC7 prime-AdC68 boost vaccine is a promising candidate for further development to combat EBOV infections.

SUBMITTER: Yang X

PROVIDER: S-EPMC6711196 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Chimpanzee adenoviral vector prime-boost regimen elicits potent immune responses against Ebola virus in mice and rhesus macaques.

Yang Xi X Wang Xiang X Song Yufeng Y Zhou Ping P Li Dapeng D Zhang Chao C Jin Xia X Huang Zhong Z Zhou Dongming D

Emerging microbes & infections 20190101 1

In the last few decades, Ebola virus (EBOV) has emerged periodically and infected people in Africa, resulting in an extremely high mortality rate. With no available prophylaxis or cure so far, a highly effective Ebola vaccine is urgently needed. In this study, we developed a novel chimpanzee adenovirus-based prime-boost vaccine by exploiting two recombinant replication-deficient chimpanzee adenoviral vectors, AdC7 and AdC68, which express glycoproteins (GP) of the EBOV strain identified in the 2 ...[more]

PMID: 31339465

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Chimpanzee adenoviral vector prime-boost regimen elicits potent immune responses against Ebola virus in mice and rhesus macaques.

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Chimpanzee adenoviral vector prime-boost regimen elicits potent immune responses against Ebola virus in mice and rhesus macaques.

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