Search results for "vaccines"

Mosaic particles formed by wild-type hepatitis B virus core protein and its deletion variants consist of both homo- and heterodimers.

2003

AbstractCo-expression in Escherichia coli of wild-type (wt) hepatitis B virus core protein (HBc) and its naturally occurring variants with deletions at amino acid positions 77–93 or 86–93 leads to formation of mosaic particles, which consist of three dimer subunit compositions. These compositions are wt/variant HBc heterodimers and two types of homodimers, formed by wt HBc or the variant HBc themselves. Mosaic particles were found also when both HBc deletion variants 77–93 and 86–93 were co-expressed in E. coli. These findings are discussed in terms of their significance for hepatitis B virus pathogenesis and prospective use of mosaic particles in vaccine development.

Clinical update on risks and efficacy of anti-SARS-CoV-2 vaccines in patients with autoimmune hepatitis and summary of reports on post-vaccination li…

2022

Patients with liver diseases, especially those with cirrhosis, have an increased mortality risk when infected by SARS-CoV-2 and therefore anti-SARS-CoV-2 vaccine has been recommended by leading Scientific Associations for all patients with chronic liver diseases. However, previous reports have shown a reduced antibody response following the full course of vaccination in immunosuppressed patients, including liver transplant recipients and several rheumatic diseases. This document, drafted by an expert panel of hepatologists appointed by the Italian Association for the Study of the Liver (AISF), aims to present the updated scientific data on the safety and efficacy of anti-SARS-CoV-2 mRNA vac…

Spontaneous Remission of Recalcitrant Warts in Girls After Human Papillomavirus Vaccination

2016

Potential impact of a nonavalent anti HPV vaccine in Italian men with and without clinical manifestations

2021

AbstractHuman papilloma virus infection (HPV) is the most common sexually transmitted disease. Little is known about male infection. Nonavalent vaccine against types 6/11/16/18/31/33/45/52/58 was approved and neutral gender immunization programs have been proposed. This study evaluates the potential impact of nonavalent vaccine compared to quadrivalent in male living in Sicily (Italy). 58.7% of samples were HPV positive and forty-four types of HPV were identified. A significant higher estimated coverage of nonavalent vaccine than quadrivalent was observed (64.3% vs. 45.8%), with absolute and relative additional impact of 20.1% and 47.2%, respectively. Low impact of the vaccine were calculat…

Optimized recombinant dense bodies of human cytomegalovirus efficiently prime virus specific lymphocytes and neutralizing antibodies without the addi…

2010

Control of human cytomegalovirus (HCMV) infection correlates with the reconstitution of antiviral T lymphocytes in haematopoietic stem cell transplant recipients. A vaccine to foster this reconstitution and to ameliorate the severe consequences of HCMV reactivation is yet unavailable. This work focused on providing a rationale for the amendment of the yields and the antigenic composition of a vaccine, based on subviral dense bodies (DB) of HCMV. Modified DB were generated that contained the HLA-A2 presented IE1 model peptide TMYGGISLL, integrated at different positions in the major DB protein pp65. Insertion at position W175 of pp65 allowed efficient formation of recDB in the cytoplasm of i…

Cytomegalovirus and varicella–zoster virus vaccines in hematopoietic stem cell transplantation

2009

Impairment of cellular immunity upon hematopoietic stem cell transplantation (HSCT) may lead to serious clinical manifestations induced by human cytomegalovirus (HCMV) and varicella-zoster virus (VZV) infections. Although the clinical presentations, preferential organ involvement and clinical courses are different, infections with both herpesviruses are similar with respect to many pathophysiological aspects and the therapeutic strategies that are employed to combat them. Antiviral drug prophylaxis and therapy are successfully used to limit the risk of reactivated HCMV and VZV infections, but are unable to absolutely prevent episodes of virus disease in long-term follow-up after HSCT. Contr…

Development of novel vaccine strategies against human cytomegalovirus infection based on subviral particles.

2002

Abstract Background: Pre- and perinatal human cytomegalovirus (HCMV) infection remains one of the major causes of mental defects and sensineural hearing loss in children. In addition, it is a prominent infectious complication in immunosuppressed individuals such as AIDS patients or transplant recipients. Therefore, the development of an HCMV vaccine has been given top priority by health care institutions. Study design: Defective subviral particles of HCMV, termed Dense Bodies (DB) contain the dominant target antigens for humoral and cellular immune responses elicited during natural infection. These enveloped particles are released from infected culture cells and can be purified by gradient …

Experimental Preemptive Immunotherapy of Murine Cytomegalovirus Disease with CD8 T-Cell Lines Specific for ppM83 and pM84, the Two Homologs of Human …

2001

ABSTRACTCD8 T cells are the principal antiviral effectors controlling cytomegalovirus (CMV) infection. For human CMV, the virion tegument protein ppUL83 (pp65) has been identified as a source of immunodominant peptides and is regarded as a candidate for cytoimmunotherapy and vaccination. Two sequence homologs of ppUL83 are known for murine CMV, namely the virion protein ppM83 (pp105) expressed late in the viral replication cycle and the nonstructural protein pM84 (p65) expressed in the early phase. Here we show that ppM83, unlike ppUL83, is not delivered into the antigen presentation pathway after virus penetration before or in absence of viral gene expression, while other virion proteins o…

Protein delivery by subviral particles of human cytomegalovirus

2003

Direct protein delivery is an emerging technology in vaccine development and gene therapy. We could previously show that subviral dense bodies (DB) of human cytomegalovirus (HCMV), a beta-herpesvirus, transport viral proteins into target cells by membrane fusion. Thus these non-infectious particles provide a candidate delivery system for the prophylactic and therapeutic application of proteins. Here we provide proof of principle that DB can be modified genetically. A 55 kDa fusion protein consisting of the green fluorescent protein and the neomycin phosphotransferase could be packed in and delivered into cells by recombinant DB in a functional fashion. Furthermore, transfer of protein into …

PeptoSomes for Vaccination: Combining Antigen and Adjuvant in Polypept(o)ide-Based Polymersomes.

2017

In this work, the first vaccine is reported based on a PeptoSome, which contains a model antigen (SIINFEKL) and adjuvant (CpG). PeptoSomes are polypept(o)ide-based polymersomes built of a block-copolymer with polysarcosine (PSar) as the hydrophilic block (X n = 111) and poly(benzyl-glutamic acid) (PGlu(OBn)) as the hydrophobic one (X n = 46). The polypept(o)ide is obtained with low dispersity index of 1.32 by controlled ring-opening polymerization. Vesicle formation by dual centrifugation technique allows for loading of vesicles up to 40 mol%. PeptoSomes are characterized by multiangle dynamic light scattering, static light scattering, and cryogenic transmission electron microscopy (cryoTEM…