Biological antivirals for treatment of adenovirus infections.

Adenovirus (Ad) infections are usually mild and self-limiting, but severe systemic infections and fatal diseases can occur, especially in immunosuppressed patients. Anti-adenoviral pharmacotherapy has been proven to inhibit Ad infection, but its efficiency is limited. This review addresses biological antiviral agents as a new class of therapeutics for treatment of Ad infections.

Enhanced suppression of adenovirus replication by triple combination of anti-adenoviral siRNAs, soluble adenovirus receptor trap sCAR-Fc and cidofovir.

Adenoviruses (Ad) generally induce mild self-limiting respiratory or intestinal infections but can also cause serious disease with fatal outcomes in immunosuppressed patients. Antiviral drug therapy is an important treatment for adenoviral infections but its efficiency is limited. Recently, we have shown that gene silencing by RNA interference (RNAi) is a promising new approach to inhibit adenoviral infection.

Impaired Endothelial Regeneration Through Human Parvovirus B19-Infected Circulating Angiogenic Cells in Patients With Cardiomyopathy.

Human parvovirus B19 (B19V) is a common pathogen in microvascular disease and cardiomyopathy, owing to infection of endothelial cells. B19V replication, however, is almost restricted to erythroid progenitor cells (ErPCs). Endothelial regeneration attributable to bone marrow-derived circulating angiogenic cells (CACs) is a prerequisite for organ function.

Antibody-mediated enhancement of parvovirus B19 uptake into endothelial cells mediated by a receptor for complement factor C1q.

Despite its strong host tropism for erythroid progenitor cells, human parvovirus B19 (B19V) can also infect a variety of additional cell types. Acute and chronic inflammatory cardiomyopathies have been associated with a high prevalence of B19V DNA in endothelial cells of the myocardium. To elucidate the mechanisms of B19V uptake into endothelium, we first analyzed the surface expression of the well-characterized primary B19V receptor P antigen and the putative coreceptors α5β1 integrins and Ku80 antigen on primary and permanent endothelial cells.

Adenovirus vector-mediated RNA interference for the inhibition of human parvovirus B19 replication.

Human parvovirus B19 (B19V) has been considered to cause acute and chronic myocarditis, which is accompanied by endothelial dysfunction. Currently, no causative treatment option for B19V-infections is available. Since RNA interference (RNAi) has proven to be a highly potent antiviral approach, the aim of the current study was to develop an RNAi-based strategy to inhibit B19V replication.

Roles of E4orf6 and VA I RNA in adenovirus-mediated stimulation of human parvovirus B19 DNA replication and structural gene expression.

Despite its very narrow tropism for erythroid progenitor cells, human parvovirus B19 (B19V) has recently been shown to replicate and form infectious progeny virus in 293 cells in the presence of early adenoviral functions provided either by infection with adenovirus type 5 or by addition of the pHelper plasmid encoding the E2a, E4orf6, and VA RNA functions. In the present study we dissected the individual influence of these functions on B19V genome replication and expression of structural proteins VP1 and VP2. We show that, in the presence of the constitutively expressed E1A and E1B, E4orf6 alone is able to promote B19V DNA replication, resulting in a concomitant increase in VP expression levels.

Transactivation of human parvovirus B19 gene expression in endothelial cells by adenoviral helper functions.

Human parvovirus B19 (B19V) DNA is highly prevalent in endothelial cells lining up intramyocardial arterioles and postcapillary venules of patients with chronic myocarditis and cardiomyopathies. We addressed the question of a possible stimulation of B19V gene expression in endothelial cells by infection with adenoviruses. Adenovirus infection led to a strong augmentation of B19V structural and nonstructural proteins in individual endothelial cells infected with B19V or transfected with an infectious B19V genome.

Inhibition of adenovirus infections by siRNA-mediated silencing of early and late adenoviral gene functions.

Adenoviruses are pathological agents inducing mild respiratory and gastrointestinal infections. Under certain circumstances, for example in immunosuppressed patients, they induce severe infections of the liver, heart and lung, sometimes leading to death. Currently, adenoviral infections are treated by palliative care with no curative antiviral therapy yet available.

In utero transmission of porcine torque teno viruses.

Sera and selected tissue homogenates collected from gnotobiotic swine never exposed to the environment or other swine tissues were tested for the presence of porcine torque teno virus (TTV) DNAs by nested and non-nested polymerase chain reactions (PCR) using primers specific for the untranslated region of porcine genogroups (g) 1 and 2. Twenty-three of 105 (21.9%) gnotobiotic piglets were g1- and/or g2-TTV DNA positive.