Orf virus (ORFV), a member of Parapoxvirus, has evolved various strategies to modulate the immune responses of host cells. The ORFV-encoded protein ORFV002, a regulator factor, has been found to inhibit the acetylation of NF-κB-p65 by blocking phosphorylation of NF-κB-p65 at Ser(276) and also to disrupt the binding of NF-κB-p65 and p300. To explore the mechanism by which ORFV002 regulates NF-κB...

Orf virus (ORFV), the type member of the genus Parapoxvirus of the Poxviridae, has evolved novel strategies (proteins and/or mechanisms of action) to modulate host cell responses regulated by the nuclear factor-κB (NF-κB) signaling pathway. Here, we present data indicating that ORFV ORFV121, a gene unique to parapoxviruses, encodes a novel viral NF-κB inhibitor that binds to and inhibits the ph...

To the Editor: Recently, Murphy and Osburn (1) strongly argued for testing old smallpox vaccine stocks made in animal skin for adventitious infectious agents such as viruses, mycoplasmas, and eventually, prions. Their argument appears clearly justified after unexpected cases of myopericarditis occurred during recent campaigns of smallpox vaccinations in the United States (2). To the long list o...

Viral Characteristics Large, enveloped (some virions contain double envelope), double-stranded DNA viruses (see Fig. 10.1). The capsid / nucleocapsid is brick-shaped to ovoid containing the genome and lateral bodies (function unknown). The large complex genome consists of a single, linear molecule of double stranded DNA that codes for approximately 200 proteins. The ends are ligated to each oth...

Natural killer (NK) cell clearance of tumor cell emboli following surgery is thought to be vital in preventing postoperative metastases. Using a mouse model of surgical stress, we transferred surgically stressed NK cells into NK-deficient mice and observed enhanced lung metastases in tumor-bearing mice as compared with mice that received untreated NK cells. These results establish that NK cells...

Investigations using inhibitors of dipeptidyl peptidase IV (DP IV) activities and DP IV-/- mice indicated an immunoregulatory role of DP IV that could not be compensated by DP IV-like enzymes. The HIV-1 Tat protein was identified as the first natural inhibitor of DP IV and as immunosuppressor. This review summarizes our investigations on the identification of the amino acid motif of Tat respons...

Orf virus (ORFV; Parapoxvirus ovis) was used to develop a novel vector system for the generation of effective and safe live vaccines. Based on the attenuated ORFV strain D1701-V, recombinants were produced that express the glycoproteins gC (D1701-VrVgC) or gD (D1701-VrVgD) of the alphaherpesvirus of swine, pseudorabies virus (PRV). Expression of gC and gD was also demonstrated on the surface of...