Jonatan Ersching a, Malva I.M. Hernandez b, Fabrizzio S. Cezarotto c, Jovino D.S. Ferreira d, Amely B. Martins e, William M. Switzer g, Zhiquan Xiang f, Hildegund C.J. Ertl f, Carlos R. Zanetti a, Aguinaldo R. Pinto |
a b s t r a c t Keywords: Human adenovirus , Simian adenovirus, Neutralizing antibody, Seroneutralization assay, Vaccines
Vaccines based on adenovirus (Ad) vectors are currently in development against several pathogens. However, neutralizing antibodies (NAb) to human adenovirus type 5 (AdHu5), the best-studied vector, are highly prevalent in humans worldwide. Less-prevalent adenoviruses, including human and simian serotypes, provide alternative vaccine platforms. In this study, sera from 200 Brazilian human subjects and New-World monkeys were tested for NAb titers to human serotypes AdHu5 and AdHu26 and chimpanzee-origin Ad viruses of serotype 6 (AdC6) and serotype 68 (AdC68). Seroprevalence rates of NAb in humans were 69.5% for AdHu5, 44% for AdHu26, 21% for AdC6 and 23.5% for AdC68. In addition, NAb titers to human Ad were consistently higher than those found to simian serotypes. Surprisingly, sera from some New-World monkey species were able to neutralize AdC6 and/or AdC68. A possible explanation for these findings and the implications for the development of Ad-vector vaccines are discussed in detail |