Disclosed is a method for producing an antibody reagent for detecting a test substance in a sample by an immune complex transfer method. The method comprises the steps of: bringing an antibody solution comprising a labeled antibody capable of binding to the test substance into contact with a solid phase used in the immune complex transfer method; and separating the solid phase and the antibody solution to prepare the antibody reagent from the antibody solution.

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.

A kit for quantitatively detecting HBsAg and a method for quantitatively detecting an HBsAg content in a sample containing HBsAg. The kit comprises a first antibody specifically binding to HBsAg and a reagent composition. The reagent composition comprises tris(2-carboxyethyl)phosphine hydrochloride (TCEP) and urea.

An examination system that recognizes a glycosylated antigen in Dane particles of hepatitis B virus (HBV) and a neutralizing antibody that recognizes the glycosylated antigen and that exhibits an infection-inhibiting activity. It was elucidated that Dane particles are associated with specific glycan structures, and this enabled the construction of a new detection system for infectious, i.e., nucleic acid-containing, hepatitis B virus particles and the provision of a neutralizing antibody that recognizes a glycosylated antigen and that exhibits an infection-inhibiting activity.

Disclosed is a highly sensitive assay method and assay kit for HBsAg, which do not require treatment with a strong acid or alkali in the sample pretreatment, and which is less susceptible to influences by the autoantibodies. The assay method for hepatitis B virus s antigen in a sample separated from a living body includes: a pretreatment step of mixing a sample with a pretreatment reagent containing a reducing agent, to reduce hepatitis B virus s antigen; and an immunoassay step of subjecting the pretreated sample to an immunoassay of hepatitis B virus s antigen using at least one antibody or antigen-binding fragment thereof capable of antigen-antibody reaction with a reduced peptide composed of the amino acids at positions 98 to 179 of hepatitis B virus s antigen.

Disclosed are antibodies to anti-hepatitis B surface antigen (HBsAg) (especially humanized antibodies), nucleic acid molecules encoding same, methods for preparing same, and pharmaceutical compositions containing same. The antibodies have higher affinity for HBsAg at neutral pH than at acidic pH, thereby significantly enhancing the virus clearance efficiency and prolonging the virus inhibition time. The antibodies and the pharmaceutical compositions can be used for preventing and/or treating HBV infections or diseases related to HBV infections (e.g., hepatitis B), for neutralizing the virulence of HBV in a subject (e.g., a human), for reducing the serum level of HBV DNA and/or HBsAg in the body of the subject, or for activating the humoral immune response of the subject (e.g., a chronic HBV infected or chronic hepatitis B patient) against HBV.

Antibodies (especially humanized antibodies) against the hepatitis B surface antigen (HBsAg), a nucleic acid molecule encoding same, a method for preparing same, and a pharmaceutical composition containing same. The anti-HBsAg antibodies have a higher binding affinity to HBsAg at a neutral pH than at an acidic pH, thereby significantly enhancing virus clearance efficiency and prolonging virus inhibition time. The antibodies and pharmaceutical composition may be used to prevent and/or treat HBV infections or diseases related to HBV infection (such as hepatitis B) for use in neutralizing the virulence of HBV in the body of a subject (such as a human) to reduce a serum level of HBV DNA and/or HBsAg in the body of the subject, or to activate a humoral immune response of a subject (such as a person infected with chronic HBV or a patient who has chronic hepatitis B) against HBV.

An immunoassay apparatus may include: a sample dispenser part that dispenses a sample into a first reaction container; a reagent dispenser part that dispenses, into the first reaction container: a solid-phase reagent containing a solid-phase carrier; a labeled reagent; and a releasing reagent that releases, from the solid-phase carrier, an immune complex including a target substance and a labeled substance; a measurement part that measures a signal based on the labeled substance in the immune complex in a second reaction container; a container supply part that stores a plurality of reaction containers; a transfer part that transfers the first reaction container so that the sample dispenser part and the reagent dispenser part perform a dispensing operation to the first reaction container, and that transfers the second reaction container so that the immune complex dispended from the first reaction container is dispensed into the second container.

Disclosed is a method for producing an antibody reagent for detecting a test substance in a sample by an immune complex transfer method. The method comprises the steps of: bringing an antibody solution comprising a labeled antibody capable of binding to the test substance into contact with a solid phase used in the immune complex transfer method; and separating the solid phase and the antibody solution to prepare the antibody reagent from the antibody solution.

Disclosed is a liquid-sealed cartridge in which a liquid is transferred by a centrifugal force generated when the liquid-sealed cartridge is rotated around a rotation shaft, including: a liquid storage portion configured to store the liquid therein; a seal having an outer peripheral portion connected to the liquid storage portion, the seal being configured to seal the liquid storage portion; a flow path connected to the liquid storage portion via the seal, through which the liquid in the liquid storage portion is transferred by the centrifugal force in a direction away from the rotation shaft, wherein, when the seal receives a pressing force, the seal is inclined in a pressing direction, with one portion of the outer peripheral portion thereof remaining connected with the liquid storage portion, and the other portion of the outer peripheral portion being separated from the liquid storage portion.