47 research outputs found
In vivo combination of human anti-envelope glycoprotein E2 and -Claudin-1 monoclonal antibodies for prevention of hepatitis C virus infection
Despite the development of direct-acting antivirals (DAAs), hepatitis C virus (HCV) infection remains a major cause for liver disease and cancer worldwide. Entry inhibitors block virus host cell entry and, therefore, prevent establishment of chronic infection and liver disease. Due to their unique mechanism of action, entry inhibitors provide an attractive antiviral strategy in organ transplantation. In this study, we developed an innovative approach in preventing HCV infection using a synergistic combination of a broadly neutralizing human monoclonal antibody (HMAb) targeting the HCV E2 protein and a host-targeting anti-claudin 1 (CLDN1) humanized monoclonal antibody. An in vivo proof-of-concept study in human liver-chimeric FRG-NOD mice proved the efficacy of the combination therapy at preventing infection by an HCV genotype 1b infectious serum. While administration of individual antibodies at lower doses only showed a delay in HCV infection, the combination therapy was highly protective. Furthermore, the combination proved to be effective in preventing infection of primary human hepatocytes by neutralization-resistant HCV escape variants selected during liver transplantation, suggesting that a combination therapy is suited for the neutralization of difficult-to-treat variants. In conclusion, our findings suggest that the combination of two HMAbs targeting different steps of virus entry improves treatment efficacy while simultaneously reducing treatment duration and costs. Our approach not only provides a clinical perspective to employ HMAb combination therapies to prevent graft re-infection and its associated liver disease but may also help to alleviate the urgent demand for organ transplants by allowing the transplantation of organs from HCV-positive donors
Composition of the Top Management Team and Firm International Diversification
This study investigates the impact of various top management team characteristics on firm international diversification. Relying on data from 126 firms in the electronics industry, we find that certain top management team characteristics are related to international expansion. Specifically, results indicate that lower average age, higher average tenure, higher average elite education, higher average international experience, and higher tenure heterogeneity are associated with firm international diversification. The study reinforces the importance of top management team composition in internationalization decisions and suggests further research in this context.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
UGRP1, a Uteroglobin/Clara Cell Secretory Protein-Related Protein, Is a Novel Lung-Enriched Downstream Target Gene for the T/EBP/NKX2.1 Homeodomain Transcription Factor
A novel gene that is down-regulated in lungs of
T/ebp/Nkx2.1-null mouse embryos has been identified
using a suppressive-subtractive hybridization method. The gene product
is a secreted protein, forms a homodimer, and exhibits an amino acid
sequence similar to that seen in the uteroglobin/Clara cell secretory
protein family of proteins. This gene, designated Ugrp1
(uteroglobin-related protein 1), consists of three exons and two
introns and produces three transcripts by alternative splicing. The
Ugrp1 gene was localized by fluorescence in
situ hybridization to mouse chromosome 18 at region 18C-D; this
region is homologous with human 5q31-34, where one of the asthma
susceptibility genes has been assigned. UGRP1 mRNA is predominantly
expressed in the lung, with low levels of expression in the thyroid.
Expression in the lung is detectable as early as embryonic day
12.5 and increases markedly by embryonic day 16.5. In
T/ebp/Nkx2.1-null embryo lungs, UGRP1 expression was
significantly reduced as assessed by RT-PCR analysis. Cotransfection
assays using a T/EBP/NKX2.1 expression construct with
Ugrp1 promoter-luciferase reporter constructs confirmed
that T/EBP/NKX2.1 regulates Ugrp1 gene activity at the
transcriptional level. Thus, Ugrp1 is a downstream
target gene for the T/EBP/NKX2.1 homeodomain transcription factor.
Changes in UGRP1 mRNA levels in lungs from antigen-sensitized mice
suggest the possible involvement of UGRP1 in inflammation
A Polymorphism in the Human UGRP1 Gene Promoter That Regulates Transcription Is Associated with an Increased Risk of Asthma
Several traits associated with asthma phenotypes, such as high total serum immunoglobulin E and bronchial hyperresponsiveness, have been linked by numerous genome-screen studies and linkage analyses to markers on human chromosome 5q31-q34. In the present article, we describe UGRP1 (encoding uteroglobin-related protein 1) as one of asthma-susceptibility genes that is located on chromosome 5q31-q32. UGRP1 is a homodimeric secretory protein of 17 kDa and is expressed only in lung and trachea. The G→A polymorphism was identified at −112 bp in the human UGRP1 gene promoter. The −112A allele is responsible for a 24% reduction in the promoter activity in relation to the −112G allele, as examined by transfection analysis. Electrophoretic mobility-shift analysis revealed that an unknown nuclear factor binds to the region around −112 bp. The binding affinity with the −112A oligonucleotide was reduced by approximately one half, as compared with the −112G oligonucleotide. In a case-control study using 169 Japanese individuals (84 patients with asthma and 85 healthy control individuals), those with a −112A allele (G/A or A/A) were 4.1 times more likely to have asthma than were those with the wild-type allele (G/G)
SMAD5 Gene Expression, Rearrangements, Copy Number, Amplification at Fragile Site FRA5C in Human Hepatocellular Carcinoma
AbstractSignaling by the transforming growth factor (TGF)family members is transduced from the cell surface to the nucleus by the Smad group of intracellular proteins. Because we detected alterations on the long arm of chromosome 5, we examined the status of the SMAD5 gene in human hepatocellular carcinoma (HCC) cell lines and primary HCC. In 16 cell lines, chromosome alterations of chromosome 5 were observed in nine cell lines by fluorescence in situ hybridization (FISH), an increase in SMAD5 gene copy number relative to the ploidy level was found in eight lines. The breakpoints in unbalanced translocations and deletions frequently occurred near the SMAD5 locus, but apparently did not cause loss of SMAD5. In one cell line, where comparative genomic hybridization showed DNA copy number gain confined to the region 5831, we detected by FISH high-level amplification of the SMAD5 gene located within the fragile site FRA5C. Semiquantitative polymerase chain reaction did not reveal changes in SMAD5 DNA levels in 15 of 17 primary HCC specimens. In 17 HCC cell lines, SMAD5 mRNA levels were either maintained or upregulated by an increase in gene dosage or another mechanism. Collectively, our results show that SMAD5 undergoes copy number gain and increased expression, rather than loss of expression, therefore suggest that this gene does not act as a tumorsuppressor gene in HCC. The Hep-40 HCC cell line with high-level amplification and significant overexpression of SMAD5 may be useful in studying the interaction of SMAD5 with other genes