Experiments were conducted to analyze the equine herpesvirus 1 (EHV-1) gene 68 product which is encoded by the EHV-1 Us2 homolog. An antiserum directed against the amino-terminal 206 amino acids of the EHV-1 Us2 protein specifically detected a protein with an Mr of 34,000 in cells infected with EHV-1 strain RacL11. EHV-1 strain Ab4 encodes a 44,000-Mr Us2 protein, whereas vaccine strain RacH, a...

This report describes the first detection of an equine herpesvirus 1 (EHV-1) neuropathogenic variant (G2254/D752) in Brazil from a case of fatal equine herpesvirus myeloencephalopathy (EHM) in a mare. The results of nucleotide sequencing of the EHV-1 ORF30 gene showed that two other Brazilian EHV-1 isolates from EHM cases are representatives of the non-neuropathogenic variant (A2254/N752), sugg...

Two antigenically similar subtypes of equine herpesvirus 1 (EHV-1) cause disease in horses. A procedure for rapid differentiation of the two EHV-1 subtypes with monoclonal antibodies was developed. Subtype-specific pools of monoclonal antibodies were constructed, characterized, and used in enzyme immunofiltration and indirect immunofluorescence assays to subtype 50 epizootiologically unrelated ...

Herpesviruses occasionally cause lethal infection in alien hosts by interspecies transmission such as B virus infection in humans from Macaques and pseudorabies virus infection in various animals from pigs. Most of the infection can be characterized as lethal encephalitis. One of typical examples is equine herpesvirus 9 (EHV-9), also called as gazelle herpesvirus 1 (GHV-1), which was isolated f...

Both intranasal (i.n.) and intracerebral (i.c.) inoculation of mice with wild-type equine herpesvirus type 1 (wt EHV-1) caused clinical signs and mortality. Virus could be recovered from target organs (turbinates, lungs and blood) for several days. By contrast, the thymidine kinase (TK)-deficient deletion mutant PR1 produced markedly less clinical disease following both i.n. and i.c. inoculatio...

Gammaherpesviruses (γHV) are implicated in the pathogenesis of pulmonary fibrosis in humans and murine models of lung fibrosis, however there is little direct experimental evidence that such viruses induce lung fibrosis in the natural host. The equine γHV EHV 5 is associated with equine multinodular pulmonary fibrosis (EMPF), a progressive fibrosing lung disease in its natural host, the horse. ...

Equine Herpesvirus 9 (EHV-9) is a new member of the equine herpesviruses which was isolated from Thomson’s gazelles (Gazella thomsoni) that died of fulminant encephalitis in a Japanese zoo (Fukushi et al., 1997; Yanai et al., 1998). Previously, experimental infections of EHV-9 were conducted in various species of animals other than primates to clarify the infectivity and virulence of this virus...

Equine herpesvirus type 4 (EHV-4) is a major respiratory pathogen of horses. Unlike most other members of the Alphaherpesvirinae, EHV-4 was regarded as non-neurotropic. Here, neural and lymphoid tissues of 17 horses have been analysed post-mortem. EHV-4 DNA was detected in 11 cases (65%) by PCR, exclusively in the trigeminal ganglia. In order to define the transcriptional activity, RNA preparat...

A line of mouse 3T3 cells lacking deoxythymidine kinase (dTK-) was stably transformed to see dTK+ phenotype after exposure to ultraviolet-irradiated equine herpesvirus type 1 (EHV-1). Deoxythymidine kinase (dTK) was purified from the biochemically transformed mouse cells by affinity chromatography on deoxythymidine-Sepharose. The purified dTK from EHV-1-transformed 3T3 cells was identical to th...

Equine herpesvirus 1 (EHV-1) causes respiratory disease, abortion, neonatal death and neurological disease in equines and is endemic in most countries. The viral factors that influence EHV-1 disease severity are poorly understood, and this has hampered vaccine development. However, the N752D substitution in the viral DNA polymerase catalytic subunit has been shown statistically to be associated...