Manual of Standards for Diagnostic Tests and Vaccines

/pdf/the-family-herpesviridae-an-update-the-herpesvirus-study-1kdczqc69y.pdf

The family Herpesviridae: an update. The Herpesvirus Study Group of the International Committee on Taxonomy of Viruses.

Herpes simplex virus (HSV) infections of the central nervous system (CNS) have varied presentations. Some, such as encephalitis, can have devastating outcomes. In only a few short decades a vast amount of knowledge has been uncovered about the pathogenicity of this virus, its diagnosis, and treatment. Non-invasive diagnostics with polymerase chain reaction have replaced brain biopsy as the mainstay of diagnosis and antiviral therapy with acyclovir has largely improved mortality. However, despite these scientific advancements, morbidity remains high. The clinician must maintain a high index of suspicion with neonates, children, and adults, as HSV can often mimic other CNS diseases and prompt initiation of treatment is integral.

Herpes simplex virus.

Herpesvirus assembly: An update

Bovine herpesvirus 1 (BoHV-1), classified as an alphaherpesvirus, is a major pathogen of cattle. Primary infection is accompanied by various clinical manifestations such as infec- tious bovine rhinotracheitis, abortion, infectious pustular vulvovaginitis, and systemic infection in neonates. When animals survive, a life-long latent infection is established in nervous sensory ganglia. Several reactivation stimuli can lead to viral re-excretion, which is responsible for the maintenance of BoHV-1 within a cattle herd. This paper focuses on an updated pathogenesis based on a molecular characterization of BoHV-1 and the description of the virus cycle. Special emphasis is accorded to the impact of the latency and reactivation cycle on the epidemiology and the control of BoHV-1. Several European countries have initiated BoHV-1 eradication schemes because of the significant losses incurred by disease and trading restrictions. The vaccines used against BoHV-1 are described in this context where the differentiation of infected from vaccinated animals is of critical importance to achieve BoHV-1 eradication.

/pdf/bovine-herpesvirus-1-infection-and-infectious-bovine-5abkluz0p4.pdf

Bovine herpesvirus 1 infection and infectious bovine rhinotracheitis.

The genome of bovine herpesvirus 1 (BHV-1) strains exhibiting a neuropathogenic potential compared to known BHV-1 strains by restriction site mapping and cross-hybridization.

Herpesvirus capsids originating in the nucleus overcome the nucleocytoplasmic barrier by budding at the inner nuclear membrane. The fate of the resulting virions is still under debate. The fact that capsids approach Golgi membranes from the cytoplasmic side led to the theory of fusion between the viral envelope and the outer nuclear membrane, resulting in the release of capsids into the cytoplasm. We recently discovered a continuum from the perinuclear space to the Golgi complex implying (i) intracisternal viral transportation from the perinuclear space directly into Golgi cisternae and (ii) the existence of an alternative pathway of capsids from the nucleus to the cytoplasm. Here, we analyzed the nuclear surface by high-resolution microscopy. Confocal microscopy of MDBK cells infected with recombinant bovine herpesvirus 1 expressing green fluorescent protein fused to VP26 (a minor capsid protein) revealed distortions of the nuclear surface in the course of viral multiplication. High-resolution scanning and transmission electron microscopy proved the distortions to be related to enlargement of nuclear pores through which nuclear content including capsids protrudes into the cytoplasm, suggesting that capsids use impaired nuclear pores as gateways to gain access to the cytoplasmic matrix. Close examination of Golgi membranes, rough endoplasmic reticulum, and outer nuclear membrane yielded capsid-membrane interaction of high identity to the budding process at the inner nuclear membrane. These observations signify the ability of capsids to induce budding at any cell membrane, provided the fusion machinery is present and/or budding is not suppressed by viral proteins.

Impairment of Nuclear Pores in Bovine Herpesvirus 1-Infected MDBK Cells

Caprine herpesvirus 1 (CapHV-1) DNA was examined by electron microscopy, restriction site mapping and homology studies with bovine herpesvirus 1 (BHV-1) DNA. Although the restriction site maps differed significantly, we showed that the genome structures of CapHV-1 and BHV-1 were identical and that the DNAs shared a high degree of base sequence homology.

The genome of caprine herpesvirus 1: genome structure and relatedness to bovine herpesvirus 1.

The significance of the Golgi complex in envelopment of bovine herpesvirus 1 (BHV-1) as revealed by cryobased electron microscopy

Herpesviruses enter cells by a yet poorly understood mechanism We visualized the crucial steps of the entry pathway of bovine herpesvirus 1 (BHV-1) and BHV-5 by transmission and scanning electron microscopy, employing cryotechniques that include time monitoring, ultrarapid freezing, and freeze substitution of cultured cells inoculated with virus A key step in the entry pathway of both BHV-1 and BHV-5 is a unique fusion of the outer phospholipid layer of the viral envelope with the inner layer of the plasma membrane and vice versa resulting in “crossing” of the fused membranes and in partial insertion of the viral envelope into the plasma membrane The fusion area is proposed to function as an axis for driving the virus particle into an invagination that is concomitantly formed close to the fusion site The virus particle enters the cytoplasm through the opened tip of the invagination, and the viral envelope defuses from the plasma membrane There is strong evidence that the intact virus particle is then transported to the nuclear region

Eva Loepfe

Papers

The genome of bovine herpesvirus 1 (BHV-1) strains exhibiting a neuropathogenic potential compared to known BHV-1 strains by restriction site mapping and cross-hybridization.

Impairment of Nuclear Pores in Bovine Herpesvirus 1-Infected MDBK Cells

The genome of caprine herpesvirus 1: genome structure and relatedness to bovine herpesvirus 1.

The significance of the Golgi complex in envelopment of bovine herpesvirus 1 (BHV-1) as revealed by cryobased electron microscopy

Novel Entry Pathway of Bovine Herpesvirus 1 and 5