%0 Journal Article %A Havenga, M. %A Vogels, R. %A Zuijdgeest, D. %A Radosevic, K. %A Mueller, S. %A Sieuwerts, M. %A Weichold, F. %A Damen, I. %A Kaspers, J. %A Lemckert, A. %A van Meerendonk, M. %A van der Vlugt, R. %A Holterman, L. %A Hone, D. %A Skeiky, Y. %A Mintardjo, R. %A Gillissen, G. %A Barouch, D. %A Sadoff, J. %A Goudsmit, J. %T Novel replication-incompetent adenoviral B-group vectors: high vector stability and yield in PER.C6 cells %D 2006 %J Journal of General Virology, %V 87 %N 8 %P 2135-2143 %@ 1465-2099 %R https://doi.org/10.1099/vir.0.81956-0 %I Microbiology Society, %X Adenoviral vectors based on adenovirus type 35 (rAd35) have the advantage of low natural vector immunity and induce strong, insert-specific T- and B-cell responses, making them prime-candidate vaccine carriers. However, severe vector-genome instability of E1-deleted rAd35 vectors was observed, hampering universal use. The instability of E1-deleted rAd35 vector proved to be caused by low pIX expression induced by removal of the pIX promoter, which was located in the E1B region of B-group viruses. Reinsertion of a minimal pIX promoter resulted in stable vectors able to harbour large DNA inserts (>5 kb). In addition, it is shown that replacement of the E4-Orf6 region of Ad35 by the E4-Orf6 region of Ad5 resulted in successful propagation of an E1-deleted rAd35 vector on existing E1-complementing cell lines, such as PER.C6 cells. The ability to produce these carriers on PER.C6 contributes significantly to the scale of manufacturing of rAd35-based vaccines. Next, a stable rAd35 vaccine was generated carrying Mycobacterium tuberculosis antigens Ag85A, Ag85B and TB10.4. The antigens were fused directly, resulting in expression of a single polyprotein. This vaccine induced dose-dependent CD4+ and CD8+ T-cell responses against multiple antigens in mice. It is concluded that the described improvements to the rAd35 vector contribute significantly to the further development of rAd35 carriers for mass-vaccination programmes for diseases such as tuberculosis, AIDS and malaria. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.81956-0