Role of Herpes Simplex Envelope Glycoprotein B and Toll-Like Receptor 2 in Ocular Inflammation: An ex vivo Organotypic Rabbit Corneal Model.

It has been recently reported, using in vitro studies, that the herpes simplex virus 1 (HSV-1) encoded envelope glycoprotein B (gB1) interacts with cell surface toll-like receptor 2 (TLR2) and induces the secretion of interleukin-8 (IL8), a representative marker of inflammatory cytokine activation. The purpose of this study is to investigate the role of gB1 in activating host inflammatory responses by using a secreted form of gB1 (gB1s) and an ex vivo organotypic rabbit corneal model. Abraded corneas exposed to gB1s alone or to the recombinant protein mixed with anti gB polyclonal antibody were cultured in an air-liquid interface.

Purinergic Signaling: A New Pharmacological Target Against Viruses?

Viral diseases represent a major global problem in human health, with high morbidity and mortality. Despite recent progress in antiviral treatments, several viral diseases are still not controlled and millions suffer from them every year. It has recently emerged that purinergic signaling participates in viral infection and replication.

An attenuated herpes simplex virus type 1 (HSV1) encoding the HIV-1 Tat protein protects mice from a deadly mucosal HSV1 challenge.

Herpes simplex virus types 1 and 2 (HSV1 and HSV2) are common infectious agents in both industrialized and developing countries. They cause recurrent asymptomatic and/or symptomatic infections, and life-threatening diseases and death in newborns and immunocompromised patients. Current treatment for HSV relies on antiviral medications, which can halt the symptomatic diseases but cannot prevent the shedding that occurs in asymptomatic patients or, consequently, the spread of the viruses.

Herpes simplex virus growth, preparation, and assay.

In order to study the biology of herpes simplex virus or to use it as a vector in gene therapy, it is necessary to grow the virus and to prepare virus stocks. Many different protocols are available from different research groups working with herpes simplex virus type 1 or 2 (HSV-1 or HSV-2). This chapter describes the procedures used in our laboratory.

Intranasal immunization in mice with non-ionic surfactants vesicles containing HSV immunogens: a preliminary study as possible vaccine against genital herpes.

The purpose of this study was to investigate the potential of intranasal immunization with non-ionic surfactant vesicles (NISV) containing either the secretory recombinant form of glycoprotein B (gBs) of herpes simplex virus type 1 or a related polylysine reach peptides (DTK) for induction of protective immunity against genital herpes infection in mice. NISV were prepared by lipid film hydration method. The mean diameter of vesicles was around 390 nm for DTK-containing NISV (DTK-NISV) and 320 nm for gB1s-containing NISV (gB1s-NISV).

A lentiviral vector-based, herpes simplex virus 1 (HSV-1) glycoprotein B vaccine affords cross-protection against HSV-1 and HSV-2 genital infections.

Genital herpes is caused by herpes simplex virus 1 (HSV-1) and HSV-2, and its incidence is constantly increasing in the human population. Regardless of the clinical manifestation, HSV-1 and HSV-2 infections are highly transmissible to sexual partners and enhance susceptibility to other sexually transmitted infections. An effective vaccine is not yet available.

Characterization of herpes simplex virus 1 strains as platforms for the development of oncolytic viruses against liver cancer.

Background: Diverse oncolytic viruses (OV) are being designed for the treatment of cancer. The characteristics of the parental virus strains may influence the properties of these agents.

Aims: To characterize two herpes simplex virus 1 strains (HSV-1 17syn(+) and HFEM) as platforms for virotherapy against liver cancer.

Novel tumour-specific promoters for transcriptional targeting of hepatocellular carcinoma by herpes simplex virus vectors.

Background: Hepatocellular carcinoma (HCC) is a cancer of poor prognosis, with limited success in patient treatment, which it makes an excellent target for gene therapy and viral oncolysis. Accordingly, herpes virus simplex type-1 (HSV-1) is one of the most promising viral platforms for transferring therapeutic genes and the development of oncolytic vectors that can target, multiply in, and eradicate hepatoma cells via their lytic cycle. Enhanced efficacy and specificity of HSV-1-based vectors towards HCC may be achieved by using HCC-specific gene promoters to drive selective viral gene expression and accomplish conditional replication and/or to control the expression of therapeutic genes.

APP processing induced by herpes simplex virus type 1 (HSV-1) yields several APP fragments in human and rat neuronal cells.

Lifelong latent infections of the trigeminal ganglion by the neurotropic herpes simplex virus type 1 (HSV-1) are characterized by periodic reactivation. During these episodes, newly produced virions may also reach the central nervous system (CNS), causing productive but generally asymptomatic infections. Epidemiological and experimental findings suggest that HSV-1 might contribute to the pathogenesis of Alzheimer's disease (AD).

HSV Recombinant Vectors for Gene Therapy.

The very deep knowledge acquired on the genetics and molecular biology of herpes simplex virus (HSV), has allowed the development of potential replication-competent and replication-defective vectors for several applications in human healthcare. These include delivery and expression of human genes to cells of the nervous systems, selective destruction of cancer cells, prophylaxis against infection with HSV or other infectious diseases, and targeted infection to specific tissues or organs. Replication-defective recombinant vectors are non-toxic gene transfer tools that preserve most of the neurotropic features of wild type HSV-1, particularly the ability to express genes after having established latent infections, and are thus proficient candidates for therapeutic gene transfer settings in neurons.

HSV-1-derived helper-independent defective vectors, replicating vectors and amplicon vectors, for the treatment of brain diseases.

HSV-1 is a neurotropic virus that displays several important adaptations to the nervous system of the host organism, each of which can be rationally exploited in the design of gene therapy vectors for neurological applications. Replication-incompetent (replication-defective) helper-independent recombinant vectors are nontoxic tools for gene transfer that preserve most of the neurotropic features of HSV-1, particularly the ability to express genes after establishing latent infections, and are thus proficient candidates for therapeutic gene transfer in neurons. A clinical trial with the use of a replication-incompetent vector, NP-2 (Diamyd Inc), for the treatment of pain has been initiated.

HSV as a vector in vaccine development and gene therapy.

The very deep knowledge acquired on the genetics and molecular biology of herpes simplex virus (HSV), major human pathogen whose lifestyle is based on a long-term dual interaction with the infected host characterized by the existence of lytic and latent infections, has allowed the development of potential vectors for several applications in human healthcare. These include delivery and expression of human genes to cells of the nervous system, selective destruction of cancer cells, prophylaxis against infection with HSV or other infectious diseases and targeted infection of specific tissues or organs. Three different classes of vectors can be derived from HSV-1: replication-competent attenuated vectors, replication-incompetent recombinant vectors and defective helper-dependent vectors known as amplicons.

Identification of replication-competent HSV-1 Cgal+ strain targets in a mouse model of human hepatocarcinoma xenograft.

Recent studies based on animal models have shown the advantages and potential of oncolytic viral therapy using HSV-1 -based replication-competent vectors in the treatment of liver tumors, but little is known about the cellular targets that are modulated during viral infection. In the present work, we have studied the effects of intratumoral injections of HSV-1 Cgal(+) strain in a murine model of human hepatoma xenografts. Viral replication was assessed for more than 1month, leading to a significant reduction of tumor growth rate mediated, in part, by a cyclin B dependent cell proliferation arrest.

Localized delivery of fibroblast growth factor-2 and brain-derived neurotrophic factor reduces spontaneous seizures in an epilepsy model.

A loss of neurons is observed in the hippocampus of many patients with epilepsies of temporal lobe origin. It has been hypothesized that damage limitation or repair, for example using neurotrophic factors (NTFs), may prevent the transformation of a normal tissue into epileptic (epileptogenesis). Here, we used viral vectors to locally supplement two NTFs, fibroblast growth factor-2 (FGF-2) and brain-derived neurotrophic factor (BDNF), when epileptogenic damage was already in place.

Inhibition of herpes simplex virus types 1 and 2 in vitro infection by sulfated derivatives of Escherichia coli K5 polysaccharide.

Herpes simplex virus type 1 (HSV-1) and HSV-2 are neurotropic viruses and common human pathogens causing major public health problems such as genital herpes, a sexually transmitted disease also correlated with increased transmission and replication of human immunodeficiency virus type 1 (HIV-1). Therefore, compounds capable of blocking HIV-1, HSV-1, and HSV-2 transmission represent candidate microbicides with a potential added value over that of molecules acting selectively against either infection. We report here that sulfated derivatives of the Escherichia coli K5 polysaccharide, structurally highly similar to heparin and previously shown to inhibit HIV-1 entry and replication in vitro, also exert suppressive activities against both HSV-1 and HSV-2 infections.

HSV as a vector in vaccine development and gene therapy.

The very deep knowledge acquired on the genetics and molecular biology of herpes simplex virus (HSV), major human pathogen whose lifestyle is based on a long-term dual interaction with the infected host characterized by the existence of lytic and latent infections, has allowed the development of potential vectors for several applications in human healthcare. These include delivery and expression of human genes to cells of the nervous system, selective destruction of cancer cells, prophylaxis against infection with HSV or other infectious diseases and targeted infection of specific tissues or organs. Three different classes of vectors can be derived from HSV-1: replication-competent attenuated vectors, replication-incompetent recombinant vectors and defective helper-dependent vectors known as amplicons.

An S/MAR-based infectious episomal genomic DNA expression vector provides long-term regulated functional complementation of LDLR deficiency.

Episomal gene expression vectors offer a safe and attractive alternative to integrating vectors. Here we describe the development of a high capacity episomal vector system exploiting human episomal retention sequences to provide efficient vector maintenance and regulated gene expression through the delivery of a genomic DNA locus. The iBAC-S/MAR vector is capable of the infectious delivery and retention of large genomic DNA transgenes by exploiting the high transgene capacity of herpes simplex virus type 1 (HSV-1) and the episomal retention properties of the scaffold/matrix attachment region (S/MAR).

Replication-deficient mutant Herpes Simplex Virus-1 targets professional antigen presenting cells and induces efficient CD4+ T helper responses.

Both neutralizing antibodies and cytotoxic T-cells are necessary to control a viral infection. However, vigorous T helper responses are essential for their elicitation and maintenance. Here we show that a recombinant replication-deficient Herpes Simplex Virus (HSV)-1 vector encoding the Human Immunodeficiency Virus (HIV)-1 matrix protein p17 (T0-p17) was capable of infecting professional antigen presenting cells (APCs) in vitro and in vivo.

Expression of human immunodeficiency virus type 1 tat from a replication-deficient herpes simplex type 1 vector induces antigen-specific T cell responses.

Herpes simplex type-1 virus (HSV-1) based vectors have been widely used in different gene therapy approaches and also as experimental vaccines against HSV-1 infection. Recent advances in the HSV-1 technology do support the use of replication defective HSV-1 as vaccine vectors for delivery of foreign antigens. We have examined the ability of a recombinant replication-defective HSV-1 vector expressing the HIV-1 Tat protein to induce long-term Tat-specific immune responses in the Balb/c murine model.

HIV-1 matrix protein p17 modulates in vivo preactivated murine T-cell response and enhances the induction of systemic and mucosal immunity against intranasally co-administered antigens.

HIV-1 p17 is a viral cytokine that acts on preactivated, but not on resting, human T cells promoting proliferation, proinflammatory cytokines release and HIV-1 replication, after binding to a cellular receptor (p17R). Here, we demonstrate that p17Rs are expressed on activated murine T cells, which respond to p17 stimulation similarly to their human counterpart. We developed a mouse model of abortive HSV-1 infection to induce T cell activation in vivo.

HSV-1-derived recombinant and amplicon vectors for gene transfer and gene therapy.

Herpes simplex virus type 1 (HSV-1) is a major human pathogen whose lifestyle is based on a long-term dual interaction with the infected host characterized by the existence of lytic and latent infections. Although in most cell types infection with HSV-1 will induce toxic effects ending in the death of the infected cells, the very deep knowledge we possess on the genetics and molecular biology of HSV-1 has permitted the deletion of most toxic genes and the development of non-pathogenic HSV-1-based vectors for gene transfer. Several unique features of HSV-1 make vectors derived from this virus very appealing for preventive or therapeutic gene transfer.

Immunotherapeutic activity of a recombinant combined gB-gD-gE vaccine against recurrent HSV-2 infections in a guinea pig model.

The guinea pig model of recurrent genital herpes simplex virus type 2 (HSV-2) infection was used to test the immunotherapeutic activity of a glycoprotein subunit vaccine. Vaccine formulation consisted of three recombinant herpes simplex virus (HSV) glycoproteins, namely gB1s, gD2t and gE1t, plus aluminium hydroxide [Al(OH)3)] adjuvant. One month after viral challenge, infected animals were therapeutically immunised by seven subcutaneous injections of a low dose of antigens with a weekly interval for the first five and a fortnightly interval for the last two administrations.

Herpesvirus/retrovirus chimeric vectors.

Over the years, the design of HSV-1 based vectors has developed from different types of replicative-defective and replication-conditioned recombinant viruses to plasmid based amplicon vectors. More recently hybrid or chimeric vectors have incorporated desired elements of different viruses to increase the efficacy of gene delivery in vitro and in vivo. Amongst different systems, herpesvirus/retrovirus chimeras take advantage of the features of the HSV-1 vectors to efficiently transduce large amounts of foreign genetic sequences, remaining episomal, to allow production of recombinant retrovirus vectors able to stably integrate into the cellular genome.

Specific targeted binding of herpes simplex virus type 1 to hepatocytes via the human hepatitis B virus preS1 peptide.

To improve the utility of herpes simplex virus type 1 (HSV-1) vectors for gene therapy, the viral envelope needs to be manipulated to achieve cell-specific gene delivery. In this report, we have engineered an HSV-1 mutant virus, KgBpK(-) gC(-), deleted for the glycoprotein C (gC) and the heparan sulfate-binding domain (pK) of gB, in order to express gC:preS1 and gC:preS1 active peptide (preS1ap) fusion molecules. PreS1, and a 27 amino acid active peptide inside preS1 (preS1ap), are supposed to be the molecules that the human hepatitis B virus (HBV) needs to bind specifically to hepatocytes.

Protection from bacterial infection by a single vaccination with replication-deficient mutant herpes simplex virus type 1.

Adaptive immune responses in which CD8(+) T cells recognize pathogen-derived peptides in the context of major histocompatibility complex class I molecules play a major role in the host defense against infection with intracellular pathogens. Cells infected with intracellular bacteria such as Listeria monocytogenes, Salmonella enterica serovar Typhimurium, or Mycobacterium tuberculosis are directly lysed by cytotoxic CD8(+) T cells. For this reason, current vaccines for intracellular pathogens, such as subunit vaccines or viable bacterial vaccines, aim to generate robust cytotoxic T-cell responses.