The method for producing a particle for immunoassay for detecting an anti-HBS antibody, characterized by including a first step of covalently binding an HBs antigen to a particle to obtain an HBs antigen-sensitized particle, and a second step of washing the HBs antigen-sensitized particle with a nonionic surfactant or an amphoteric surfactant to obtain a washed HBs antigen-sensitized particle. Also, the method for producing a particle for immunoassay for detecting an anti-HBs antibody, characterized by including a first step of covalently binding an HBs antigen to a particle to obtain an HBs antigen-sensitized particle, and a third step of washing the HBs antigen-sensitized particle with an acidic aqueous solution to obtain a washed HBs antigen-sensitized particle.

Provided is an affinity particle for detecting immunoglobulin G in a human specimen by a latex agglutination method, wherein the affinity particle has a volume-average particle diameter of 400 nm or less, wherein the affinity particle includes a latex particle and a protein carried on a surface of the latex particle, wherein the protein contains an antigen having a molecular weight of 10,000 or more, and wherein an amount of the protein carried on the surface of the latex particle is 1.0 g or more and 20.0 g or less per 1 mg of the affinity particle.

The present invention relates to a kit of in vitro quantifying large surface protein of hepatitis B virus (LHBS). The kit includes monoclonal antibodies having respective binding specificity for specific regions of LHBS, thereby increasing sensitivity and dynamic breadth of detecting LHBS in a biological sample. Moreover, the invention also provides a biomarker set corresponding to the specific regions of LHBS, and the biomarker set can be specifically recognized by the monoclonal antibodies, for non-invasively analyzing phases of HBV infection and hepatoma prognosis in a biological sample. Furthermore, the invention also provides a set of monoclonal antibodies for predicting, diagnosing or treating a chronic liver disease via those biomarkers in a subject in need thereof.

The present disclosure relates to antibodies, and antigen binding fragments thereof, that can bind to the antigenic loop region of hepatitis B surface antigen (HBsAg) and can neutralize infection of both hepatitis B virus (HBV) and hepatitis delta virus (HDV). The present disclosure also relates to epitopes to which the antibodies and antigen binding fragments bind, as well as to fusion proteins that comprise the antigen binding fragments, and to nucleic acids that encode and cells that produce such antibodies and antibody fragments. In addition, the present disclosure relates to the use of the antibodies and antibody fragments of the present disclosure in the diagnosis, prophylaxis and treatment of hepatitis B and hepatitis D.

A method for diagnosing hepatitis virus infection or a hepatitis disease condition in a subject based on hepatitis virus-associated biomarkers present on exosomes in a bodily fluid sample from the subject is disclosed. Also disclosed are a method for monitoring the course of a hepatitis virus infection or a hepatitis disease condition in a subject and a method for monitoring effectiveness of treatment to a subject with an anti-hepatitis virus agent based on hepatitis virus-associated biomarkers present on exosomes in bodily fluid samples from the subject, as well as a kit for diagnosing hepatitis virus infection and/or a hepatitis disease condition in a subject based on hepatitis virus-associated biomarkers on exosomes in bodily fluid samples from the subject.