The CD2v protein enhances African swine fever virus replication in the tick vector, Ornithodoros erraticus

• Published in: Virology (New York, N.Y.) Vol. 393; no. 2; pp. 319 - 328
• Main Authors: Rowlands, Rebecca J, Duarte, Margarida M, Boinas, Fernando, Hutchings, Geoff, Dixon, Linda K
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 25-10-2009
• Subjects: African swine fever; African Swine Fever - virology; African swine fever virus; African Swine Fever Virus - genetics; African Swine Fever Virus - physiology; Amino Acid Sequence; Animals; Arthropod vector; CD2; disease vectors; Hemadsorption; Infectious Disease; Ixodidae; Molecular Sequence Data; Open Reading Frames; Ornithodoros; Ornithodoros - virology; Ornithodoros erraticus; Pathogenesis; sequence analysis; Swine; viral proteins; Viral Proteins - genetics; Viral Proteins - metabolism; Virus; Virus Replication; Virus; CD2; Arthropod vector; Virus replication; African swine fever; Pathogenesis
• ISSN: 0042-6822; 1096-0341
• DOI: 10.1016/j.virol.2009.07.040

Abstract The NH/P68 non-haemadsorbing (non-HAD) African swine fever virus (ASFV) isolate contains frameshift mutations in the EP402R and adjacent EP153R genes. These encode, respectively, the protein (CD2v) that is required for the haemadsorption (HAD) of swine erythrocytes to ASFV-infected cells and a C-type lectin protein. Two recombinant HAD viruses were constructed in this parental strain. In one of these the intact EP153R gene sequence was restored. Although restoration of the HAD phenotype did not increase virus virulence in pigs, a significant increase was observed in the number of pigs which developed viraemia. These HAD recombinant viruses replicated to titres approximately 1000-fold higher than the parental non-HAD isolate when membrane fed to Ornithodoros erraticus ticks. Inoculation of the non-HAD isolate across the gut wall increased viral replication to levels comparable to that of the HAD recombinant viruses. These results demonstrate a novel role for the CD2v protein in virus replication in ticks.