This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Borca, M. V. Articles by Rock, D. L. Search for Related Content PubMed PubMed Citation Articles by Borca, M. V. Articles by Rock, D. L.

 Previous Article  |  Next Article 

J Virol, April 1998, p. 2881-2889, Vol. 72, No. 4
0022-538X/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Deletion of a CD2-Like Gene, 8-DR, from African Swine Fever Virus Affects Viral Infection in Domestic Swine

M. V. Borca, C. Carrillo, L. Zsak, W. W. Laegreid, G. F. Kutish, J. G. Neilan, T. G. Burrage, and D. L. Rock^*

Plum Island Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Greenport, New York 11944-0848

Received 17 October 1997/Accepted 31 December 1997

An African swine fever virus (ASFV) gene with similarity to the T-lymphocyte surface antigen CD2 has been found in the pathogenic African isolate Malawi Lil-20/1 (open reading frame [ORF] 8-DR) and a cell culture-adapted European virus, BA71V (ORF EP402R) and has been shown to be responsible for the hemadsorption phenomenon observed for ASFV-infected cells. The structural and functional similarities of the ASFV gene product to CD2, a cellular protein involved in cell-cell adhesion and T-cell-mediated immune responses, suggested a possible role for this gene in tissue tropism and/or immune evasion in the swine host. In this study, we constructed an ASFV 8-DR gene deletion mutant (8-DR) and its revertant (8-DR.R) from the Malawi Lil-20/1 isolate to examine gene function in vivo. In vitro, 8-DR, 8-DR.R, and the parental virus exhibited indistinguishable growth characteristics on primary porcine macrophage cell cultures. In vivo, 8-DR had no obvious effect on viral virulence in domestic pigs; disease onset, disease course, and mortality were similar for the mutant 8-DR, its revertant 8-DR.R, and the parental virus. Altered viral infection was, however, observed for pigs infected with 8-DR. A delay in spread to and/or replication of 8-DR in the draining lymph node, a delay in generalization of infection, and a 100- to 1,000-fold reduction in virus titers in lymphoid tissue and bone marrow were observed. Onset of viremia for 8-DR-infected animals was significantly delayed (by 2 to 5 days), and mean viremia titers were reduced approximately 10,000-fold at 5 days postinfection and 30- to 100-fold at later times; moreover, unlike in 8-DR.R-infected animals, the viremia was no longer predominantly erythrocyte associated but rather was equally distributed among erythrocyte, leukocyte, and plasma fractions. Mitogen-dependent lymphocyte proliferation of swine peripheral blood mononuclear cells in vitro was reduced by 90 to 95% following infection with 8-DR.R but remained unaltered following infection with 8-DR, suggesting that 8-DR has immunosuppressive activity in vitro. Together, these results suggest an immunosuppressive role for 8-DR in the swine host which facilitates early events in viral infection. This may be of most significance for ASFV infection of its highly adapted natural host, the warthog.

---

^* Corresponding author. Mailing address: Plum Island Animal Disease Center, P.O. Box 848, Greenport, NY 11944-0848. Phone: (516) 323-2500, ext. 330. Fax: (516) 323-2507.

This article has been cited by other articles:

• Chapman, D. A. G., Tcherepanov, V., Upton, C., Dixon, L. K. (2008). Comparison of the genome sequences of non-pathogenic and pathogenic African swine fever virus isolates. J. Gen. Virol. 89: 397-408 [Abstract] [Full Text]  
• Netherton, C. L., McCrossan, M.-C., Denyer, M., Ponnambalam, S., Armstrong, J., Takamatsu, H.-H., Wileman, T. E. (2006). African Swine Fever Virus Causes Microtubule-Dependent Dispersal of the trans-Golgi Network and Slows Delivery of Membrane Protein to the Plasma Membrane. J. Virol. 80: 11385-11392 [Abstract] [Full Text]  
• Boinas, F. S., Hutchings, G. H., Dixon, L. K., Wilkinson, P. J. (2004). Characterization of pathogenic and non-pathogenic African swine fever virus isolates from Ornithodoros erraticus inhabiting pig premises in Portugal. J. Gen. Virol. 85: 2177-2187 [Abstract] [Full Text]  
• Kay-Jackson, P. C., Goatley, L. C., Cox, L., Miskin, J. E., Parkhouse, R. M. E., Wienands, J., Dixon, L. K. (2004). The CD2v protein of African swine fever virus interacts with the actin-binding adaptor protein SH3P7. J. Gen. Virol. 85: 119-130 [Abstract] [Full Text]  
• Goatley, L. C., Twigg, S. R. F., Miskin, J. E., Monaghan, P., St-Arnaud, R., Smith, G. L., Dixon, L. K. (2002). The African Swine Fever Virus Protein j4R Binds to the Alpha Chain of Nascent Polypeptide-Associated Complex. J. Virol. 76: 9991-9999 [Abstract] [Full Text]  
• McCrossan, M., Windsor, M., Ponnambalam, S., Armstrong, J., Wileman, T. (2001). The trans Golgi Network Is Lost from Cells Infected with African Swine Fever Virus. J. Virol. 75: 11755-11765 [Abstract] [Full Text]  
• Leitão, A., Cartaxeiro, C., Coelho, R., Cruz, B., Parkhouse, R. M. E., Portugal, F. C., Vigário, J. D., Martins, C. L. V. (2001). The non-haemadsorbing African swine fever virus isolate ASFV/NH/P68 provides a model for defining the protective anti-virus immune response. J. Gen. Virol. 82: 513-523 [Abstract] [Full Text]