Search results for "Neutralizing antibody"

Modulation of epitope-specific anti-hepatitis C virus E2 (anti-HCV/E2) antibodies by antiviral treatment

2006

The dynamic features of three specific anti-hepatitis C virus (HCV) antibody subpopulations directed against different conformational epitopes of the viral E2 protein (HCV/E2) have been evaluated in patients with primary and persistent HCV infection; the three subpopulations are present in patients infected with different HCV genotypes and have shown a different activity using a pseudovirus neutralization assay (antibodies e301 and e137 exhibiting high neutralizing activity, while antibody e509 enhancement of HCV infectivity). In sequential samples from five patients with primary HCV infection and different virological outcome, all samples tested negative with the single exception of the e5…

Dense Bodies of a gH/gL/UL128/UL130/UL131 Pentamer-Repaired Towne Strain of Human Cytomegalovirus Induce an Enhanced Neutralizing Antibody Response

2019

The development of a vaccine against human cytomegalovirus infection (HCMV) is a high-priority medical goal. The viral pentameric protein complex consisting of glycoprotein H (gH)/gL/UL128-131A (PC) is considered to be an important vaccine component. Its relevance to the induction of a protective antibody response is, however, still a matter of debate. We addressed this issue by using subviral dense bodies (DBs) of HCMV. DBs are exceptionally immunogenic. Laboratory HCMV strain DBs harbor important neutralizing antibody targets, like the glycoproteins B, H, L, M, and N, but they are devoid of the PC. To be able to directly compare the impact of the PC on the levels of neutralizing antibody …

Prevalence of human parvovirus B19 in blood donors as determined by a haemagglutination assay and verified by the polymerase chain reaction

2002

Background and Objectives Transmission of human parvovirus B19 (PV B19) by transfusion of blood and blood products is well documented. Although PV B19 infection is connected with severe complications in some recipients, donor screening is not yet mandatory. In this study the prevalence of PV B19, as detected by a haemagglutination assay (the Human PV B19 Antigen-Test), was assessed. In addition, the persistence of B19 DNA and the serological status of blood donors was also assessed. The specificity and utility of the Human PV B19 Antigen-Test for donor screening was investigated and compared with other screening strategies. Materials and Methods The prevalence of PV B19 viraemia was assesse…

Kit Is Expressed by Epithelial Cells In Vivo

2003

In mammalian skin, stem cell factor (SCF) regulates the proliferation and maturation of mast cells and melanocytes, which are thought to be the only cutaneous cells that express the Kit-tyrosine kinase receptor (Kit) and respond to epithelial and mesenchymal-derived SCF. We previously had noted, however, the presence of Kit+ cells in murine hair follicles, in an introepithelial tissue compartment devoid of melanocytes and mast cells. Here we have identified the nature of this Kit+ population of cells in hair follicles of C57BL/6 mice. Anagen hair follicles showed strong Kit immunoreactivity not only in the pigmentary unit above the follicular dermal papilla but also in a much more proximall…

Neutralizing Antibodies Response against SARS-CoV-2 Variants of Concern Elicited by Prior Infection or mRNA BNT162b2 Vaccination.

2022

In order to determine the humoral protective response against SARS-CoV-2, the vaccine-induced and naturally induced neutralizing antibodies (NtAbs) responses against SARS-CoV-2 variants circulating in Italy through in vitro live virus neutralization assay were evaluated. A total of 39 SARS-CoV-2 recovered subjects (COVID-19+) and 63 subjects with a two-dose cycle of the BNT16262 vaccine were enrolled. A single serum sample was tested for COVID-19+ at 35–52 days post-positive swab, while vaccinees blood samples were taken at one (V1) and at three months (V3) after administration of the second vaccine dose. Significantly higher NtAb titers were found against B.1 and Alpha in both COVID-19+ an…

2020

Coxsackievirus B (CVB) enteroviruses are common human pathogens known to cause severe diseases including myocarditis, chronic dilated cardiomyopathy, and aseptic meningitis. CVBs are also hypothesized to be a causal factor in type 1 diabetes. Vaccines against CVBs are not currently available, and here we describe the generation and preclinical testing of a novel hexavalent vaccine targeting the six known CVB serotypes. We show that the vaccine has an excellent safety profile in murine models and nonhuman primates and that it induces strong neutralizing antibody responses to the six serotypes in both species without an adjuvant. We also demonstrate that the vaccine provides immunity against …

Suitability of two rapid lateral flow immunochromatographic assays for predicting SARS‐CoV‐2 neutralizing activity of sera

2020

Purpose: Assessment of commercial SARS-CoV-2 immunoassays for their capacity to provide reliable information on sera neutralizing activity is an emerging need. We evaluated the performance of two commercially-available lateral flow immunochromatographic assays (LFIC) (Wondfo SARS-CoV-2 Antibody test and the INNOVITA 2019-nCoV Ab test) in comparison with a SARS-CoV-2 neutralization pseudotyped assay for COVID-19 diagnosis in hospitalized patients, and investigate whether the intensity of the test band in LFIC associates with neutralizing antibody (NtAb) titers. Patients and Methods: Ninety sera were included from 51 patients with moderate to severe COVID-19. A green fluorescent protein (GFP)…

FRI0030 Anti-TNF-α Antibody Targeted To Inflamed Synovial Tissue for The Treatment of Rheumatoid Arthritis

2016

Background TNF-α neutralizing molecules represent one of the most efficient therapeutic approaches to control inflammation in rheumatoid arthritis (RA). The widespread distribution in the body induces the inhibition of TNF-α in all the tissues, requesting the use of high dose of this expensive drug. Another problem that has not yet been solved in the management of RA patients is how to reduce and possibly avoid the side effects, particularly the increased risk of common and opportunistic infections, which may be associated with long-term administration of these therapeutic drugs. Objectives The aim of the present investigation was to show that a recombinant protein obtained by fusing a syno…