Hepatitis C virus (HCV) infection may elicit neutralizing antibodies targeting epitopes conserved in all viral genotypes

Anti-hepatitis C virus (HCV) cross-neutralizing human monoclonal antibodies, directed against conserved epitopes on surface E2 glycoprotein, are central tools for understanding virus-host interplay, and for planning strategies for prevention and treatment of this infection. Recently, we developed a research aimed at identifying these antibody specificities. The characteristics of one of these antibodies (Fab e20) were addressed in this study. Firstly, using immunofluorescence and FACS analysis of cells expressing envelope HCV glycoproteins, Fab e20 was able to recognize all HCV genotypes. Secondly, competition assays with a panel of mouse and rat monoclonals, and alanine scanning mutagenesis analyses located the e20 epitope within the CD81 binding site, documenting that three highly conserved HCV/E2 residues (W529, G530 and D535) are critical for e20 binding. Finally, a strong neutralizing activity against HCV pseudoparticles (HCVpp) incorporating envelope glycoproteins of genotypes 1a, 1b, 2a, 2b and 4, and against the cell culture-grown (HCVcc) JFH1 strain, was observed. The data highlight that neutralizing antibodies against HCV epitopes present in all HCV genotypes are elicited during natural infection. Their availability may open new avenues to the understanding of HCV persistence and to the development of strategies for the immune control of this infection

Pulmonary metastasectomy : an overview

Metastasectomy is the most frequent surgical resection undertaken by thoracic surgeons, being the lung the second common site of metastases. The present oncological criteria for pulmonary metastasectomy are: (I) the primary cancer need to be controlled or controllable; (II) no extrathoracic metastasis-that is not controlled or controllable-exists; (III) all of the tumor must be resectable, with adequate pulmonary reserve; (IV) there are no alternative medical treatment options with lower morbidity. General favourable prognostic features in patients with pulmonary metastases are: (I) one or few metastases; (II) long disease free interval; (III) normal CEA levels in colorectal cancers. Negative predictive features in patients candidate to pulmonary metastasectomies are: (I) active primary cancer; (II) extrathoracic metastases; (III) inability to obtain surgical radicality; (IV) mediastinal lymphatic spread. The lack of controlled trials and studies limited by short follow-up and small cohorts did not allow to overcome some skepticism; moreover, the heterogeneity of these patients in terms of demographic, biologic and histologic characteristics represents a clear limit even in the largest series. On the basis of present knowledge, without results coming from on-going randomized trials, radical resection, histology, and disease free interval seem to be independent prognostic factors identifying a cohort of patients maximally benefitting from lung metastasectomy

Chimeric antigen receptor (CAR)-engineered T cells redirected against hepatitis C virus (HCV) E2 glycoprotein

Objective: The recent availability of novel antiviral drugs has raised new hope for a more effective treatment of hepatitis C virus (HCV) infection and its severe sequelae. However, in the case of non-responding or relapsing patients, alternative strategies are needed. To this end we have used chimeric antigen receptors (CARs), a very promising approach recently used in several clinical trials to redirect primary human T cells against different tumours. In particular, we designed the first CARs against HCV targeting the HCV/E2 glycoprotein (HCV/E2). Design: Anti-HCV/E2 CARs were composed of single-chain variable fragments (scFvs) obtained from a broadly cross-reactive and cross-neutralising human monoclonal antibody (mAb), e137, fused to the intracellular signalling motif of the costimulatory CD28 molecule and the CD3 zeta domain. Activity of CAR-grafted T cells was evaluated in vitro against HCV/E2-transfected cells as well as hepatocytes infected with cell culture-derived HCV (HCVcc). Results: In this proof-of-concept study, retrovirus-transduced human T cells expressing anti-HCV/E2 CARs were endowed with specific antigen recognition accompanied by degranulation and secretion of proinflammatory and antiviral cytokines, such as interferon gamma, interleukin 2 and tumour necrosis factor a. Moreover, CAR-grafted T cells were capable of lysing target cells of both hepatic and non-hepatic origin expressing on their surface the HCV/E2 glycoproteins of the most clinically relevant genotypes, including 1a, 1b, 2a, 3a, 4 and 5. Finally, and more importantly, they were capable of lysing HCVcc-infected hepatocytes. Conclusions: Clearance of HCV-infected cells is a major therapeutic goal in chronic HCV infection, and adoptive transfer of anti-HCV/E2 CARs-grafted T cells represents a promising new therapeutic tool

HCV Proteins and Immunoglobulin Variable Gene (IgV) Subfamilies in HCV-Induced Type II Mixed Cryoglobulinemia: A Concurrent Pathogenetic Role

The association between hepatitis C virus (HCV) infection and type II mixed cryoglobulinemia (MCII) is well established, but the role played by distinct HCV proteins and by specific components of the anti-HCV humoral immune response remains to be clearly defined. It is widely accepted that HCV drives the expansion of few B-cell clones expressing a restricted pool of selected immunoglobulin variable (IgV) gene subfamilies frequently endowed with rheumatoid factor (RF) activity. Moreover, the same IgV subfamilies are frequently observed in HCV-transformed malignant B-cell clones occasionally complicating MCII. In this paper, we analyze both the humoral and viral counterparts at the basis of cryoglobulins production in HCV-induced MCII, with particular attention reserved to the single IgV subfamilies most frequently involved

A biologically-validated HCV E1E2 heterodimer structural model

The design of vaccine strategies and the development of drugs targeting the early stages of Hepatitis C virus (HCV) infection are hampered by the lack of structural information about its surface glycoproteins E1 and E2, the two constituents of HCV entry machinery. Despite the recent crystal resolution of limited versions of both proteins in truncated form, a complete picture of the E1E2 complex is still missing. Here we combined deep computational analysis of E1E2 secondary, tertiary and quaternary structure with functional and immunological mutational analysis across E1E2 in order to propose an in silico model for the ectodomain of the E1E2 heterodimer. Our model describes E1-E2 ectodomain dimerization interfaces, provides a structural explanation of E1 and E2 immunogenicity and sheds light on the molecular processes and disulfide bridges isomerization underlying the conformational changes required for fusion. Comprehensive alanine mutational analysis across 553 residues of E1E2 also resulted in identifying the epitope maps of diverse mAbs and the disulfide connectivity underlying E1E2 native conformation. The predicted structure unveils E1 and E2 structures in complex, thus representing a step towards the rational design of immunogens and drugs inhibiting HCV entry

A new tetraoxa-tetraaza macrobicyclic anthracenyl luminescent receptor: control of the receptor-substrate stoichiometry

The luminescent receptor 1 incorporating anthracenyl groups as luminophores and a tetraoxa-tetraaza macrobicyclic receptor as the binding subunit has been synthesized and its interactions with Ca-II, investigated by fluorescence measurements, are reported. The receptor-substrate 1-Ca system is an example of multistability at the molecular level, triggered by a reversible modification of the receptor ability and evidenced by luminescence

Entry inhibition of HSV-1 and -2 protects mice from viral lethal challenge

The present study focused on inhibition of HSV-1 and -2 replication and pathogenesis in vitro and in vivo, through the selective targeting of the envelope glycoprotein D. Firstly, a human monoclonal antibody (Hu-mAb#33) was identified that could neutralise both HSV-1 and -2 at nM concentrations, including clinical isolates from patients affected by different clinical manifestations and featuring different susceptibility to acyclovir in vitro. Secondly, the potency of inhibition of both infection by cell-free viruses and cell-to-cell virus transmission was also assessed. Finally, mice receiving a single systemic injection of Hu-mAb#33 were protected from death and severe clinical manifestations following both ocular and vaginal HSV-1 and -2 lethal challenge. These results pave the way for further studies reassessing the importance of HSV entry as a novel target for therapeutic intervention and inhibition of cell-to-cell virus transmission

Useful resources : ethnography through the Internet

The Wide World Web (WWW) is by now an everyday fact of life. The social scientist, like the layman, cannot work without being connected to this new world, where we can access articles, references, news reports, etc., which we would previously have known nothing about unless we were in direct contact with the authors. In some respects the Internet has also brought greater democracy in the sciences: we are better informed and therefore have more opportunities to participate in conferences, calls, initiatives and events, meeting other students and researchers, and forming new relationships. E-mail enables us to contact people and exchange opinions, to do research, and to write articles with colleagues whom we have never met physically. All this takes place in real time, while we are physically located in different and sometimes very distant places: things that were impossible twenty years ago. The main aim of this research note is to collect, order and classify the principal ethnographic resources to be found on the web, and to offer it to those are interested on ethnographic method. It is obviously a partial list, because new resources are constantly becoming available on-line