Compositions and methods are disclosed herein for producing one or more immunoglobulins in an isolated B lymphocyte cell line. An isolated recombinant cell line includes an isolated B lymphocyte cell line capable of expressing at least one endogenous membrane immunoglobulin reactive to a first antigen and at least one exogenously incorporated nucleic acid encoding at least one secreted immunoglobulin reactive to a second antigen.

A method of preparing extracellularly assembled higher order antigen from a native lower order antigen the method comprising the following steps: (i) contacting lower order antigen with a solution comprising a reducing agent for a time and under 5 conditions sufficient to reduce one or more native cysteines; and (ii) removing or diluting the reducing agent or contacting the reduced lower order antigen with an oxidising agent, to elicit assembly of lower order antigen from (i) into an assembled higher order antigen; wherein at least 10% of the lower order antigen is converted to higher order antigen in step (ii) and whereby the assembled higher order antigen 10 displays at least reduced binding to non-neutralizing antibodies compared to the lower order antigen and retains binding to at least one neutralizing antibody. A method of producing a vaccine composition comprising following the steps of the method and then mixing the assembled higher order antigen with a pharmaceutically or physiologically acceptable diluent, carrier or adjuvant. A composition comprising a 15 higher order extracellularly assembled antigen, wherein the assembled antigen displays at least reduced binding to a non-neutralizing antibody compared to a native control higher order antigen. Use of the assembled higher order antigen to stimulate an immune response or for the detection and/or isolation of an immune cell such as a B-cell specific for the antigen.

Compositions and methods are disclosed herein for producing one or more immunoglobulins in an isolated B lymphocyte cell line. An isolated cell line includes an isolated B lymphocyte cell line capable of expressing at least one exogenously incorporated membrane immunoglobulin reactive to a first antigen and at least one endogenous secreted immunoglobulin reactive to a second antigen.

Novel epitope regions on hepatitis C virus E1E2 glycoprotein that induce a neutralizing antibody response in vivo are identified. Cross-neutralizing monoclonal antibodies that bind specifically to the epitopes are disclosed.

The invention relates to the field of biotechnology, and specifically to methods and techniques for neutralizing the hepatitis C virus, and specifically to antibodies against the hepatitis C virus, and can be used in medicine, the pharmaceutical industry and related areas of science and technology. Proposed is the use of fully human monoclonal antibodiesRYB1, RYB2 and RYB3and of a composition based thereon for the prevention and treatment of hepatitis C. Said antibodies are produced by cultivation using hybrid BIONA-RYB1, BIONA-RYB2 and BIONA-RYB3. The effectiveness of the antibodies is due to said antibodies binding epitopes, namely Ep1, Ep2 and Ep3 of E2 protein of the hepatitis C viral envelope, respectively. The present invention has demonstrated a neutralizing activity of the antibodies in a model system of infection of human cells in a culture. It has been shown that use of the claimed group of inventions provides for more reliable antibody binding of the hepatitis C virus.

Compositions and methods are disclosed herein for producing one or more immunoglobulins in an isolated B lymphocyte cell line. An isolated cell line includes an isolated B lymphocyte cell line capable of expressing at least one exogenously incorporated membrane immunoglobulin reactive to a first antigen and at least one endogenous secreted immunoglobulin reactive to a second antigen.

An anti-hepatitis C virus E2 protein antibody or antigen-binding antibody fragment thereof has infection inhibiting activity against hepatitis C virus (HCV). An anti-hepatitis C virus E2 protein antibody or antigen-binding antibody fragment thereof includes a certain variable region, which have infection inhibiting activity against hepatitis C virus (HCV) and exhibits an escape mutant emergence suppressive property.

The invention provides modified hepatitis C virus (HCV) E2 glycoproteins comprising the HCV-E2 receptor-binding domain (RBD) including the HVR1, HVR2 and igVR variable regions wherein in at least one of said variable regions at least a part of the variable region is replaced with a flexible linker sequence. The invention also provides vaccine compositions comprising the modified glycoproteins as well as methods of use thereof.

The present disclosure provides detection methods employing HCV core lipid binding domain and DNA binding domain monoclonal antibodies. In certain embodiments, the lipid binding domain monoclonal antibody recognizes an epitope in amino acids 141 to 161 of HCV core protein.

The present disclosure provides detection methods employing HCV core lipid binding domain and DNA binding domain monoclonal antibodies or antibody fragments. In certain embodiments, the lipid binding domain monoclonal antibody or antibody fragment recognizes an epitope in amino acids 141 to 161 of HCV core protein and the DNA binding domain antibody or antibody fragment recognizes an epitope in amino acids 95-123 (e.g., in amino acids 99-117) of HCV core protein.