HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Schröder, A. Articles by Mundt, E. Search for Related Content PubMed PubMed Citation Articles by Schröder, A. Articles by Mundt, E. Agricola Articles by Schröder, A. Articles by Mundt, E.

VP5 and the N terminus of VP2 are not responsible for the different pathotype of serotype I and II infectious bursal disease virus

Institute of Molecular Biology¹ and Infectiology³, Friedrich-Loeffler-Institutes, Federal Research Centre for Virus Diseases of Animals, D-17498 Insel Riems, Germany
Intervet International BV, NL-5830 AA Boxmeer, The Netherlands²

Author for correspondence: Egbert Mundt. Fax +49 38351 7151. e-mail Egbert.Mundt{at}rie.bfav.de

Two serotypes have been identified in infectious bursal disease virus (IBDV), a member of the family Birnaviridae. A reverse genetics system was used for generation of chimeras in genome segment A of the two serotypes, in which the complete viral VP5 gene and 3' noncoding region (NCR), or parts thereof, were exchanged. The engineered viruses were characterized in vitro and in vivo in comparison to serotype I and II IBDV. Our results show that IBDV chimeras exhibit a different phenotype in cell culture compared to the wild-type viruses. In in vitro-cultivated bursal-derived cells, chimeric viruses infected B lymphocytes, as does serotype I IBDV. Surprisingly, serotype II virus was also able to infect in vitro-cultivated bursal cells, but these were neither B lymphocytes nor macrophages. After infection of susceptible chickens all chimeras replicated in the bursa of Fabricius (BF), and three chimeric viruses caused mild depletion of bursal cells. In contrast, after infection of chickens with a chimeric IBDV containing exchanged VP5 as well as 3'-NCR, no depletion was detectable. The serotype II strain did not replicate in the BF nor did it cause depletion of bursal cells. Thus, the origin of VP5 does not explain the different pathotype of IBDV serotype I and II.