Immunodiagnosis: A Key Component of In Vitro Diagnosis

Posted by beauty33 on June 13th, 2019

immunodiagnosis, an important component of in vitro diagnosis, is used for the diagnosis of various diseases and the determination of immune status. In medicine, it is an important method to determine the cause of disease and lesion site, or to determine whether the immune status of the body is normal. In addition, it is also used in forensic blood stain identification, biochemical serum composition identification and research of species evolution. In addition, it has also been used in forensic medicine for the identification of blood stains, the identification of biochemical serum components and the study of species evolution, etc., which can be carried out in vivo and in vitro. Immunodiagnostic reagents are the most widely used in diagnostic kits and are widely used in hospitals, blood stations and physical examination centers. They are mainly used for hepatitis detection, venereal disease detection, tumor detection and pregnancy detection. Among them, immunodiagnosis includes radioimmunoassay, enzyme-linked immunoassay, chemiluminescence, etc. Enzyme-linked immunity: ELISA has the advantages of low cost and large-scale operation. Meanwhile chemiluminescence immunoassay: CLIA has the advantages of sensitive, rapid, stable, selective, reproducible, easy to operate, flexible and diverse methods.

In medicine, it is an important method to determine the cause of disease and lesion site, or to determine whether the immune status of the body is normal. Western blot theory is a hybridization technique that combines high-resolution gel electrophoresis with immunodiagnostic methods. Western blotting is also called enzyme linked immunoelectrotransfer blot (EITB) It has the advantages of high capacity, high sensitivity and high specificity, and is the most commonly used method for the detection of protein characteristics, expression and distribution, such as qualitative and quantitative detection of tissue antigens, mass determination of polypeptide molecules and antibody or antigen detection of viruses, etc.

Ria (radioimmunoassay) is a method to study the occurrence, development and transformation of the body's reaction to antigens by competitive inhibition reaction between isotopically labeled and unlabeled antigens. Radioimmunoassay involves two techniques: the first is biological. It USES the response of specific antibodies to identify a given organic substance; The second is physics. It introduces radioactive atoms into organic matter and marks them. It can measure almost any substance in the organism, including various hormones secreted by the organism itself, various drugs taken orally or injected by the patient, some virus antigens, etc., and has been widely used in clinical routine tests.

Latex enhanced immunoturbidimetric assay is a method based on the immunological precipitation reaction principle. Its basic principle is to combine the substance to be tested (antigen) in the sample with the human IgG(antibody) coated on polystyrene particles in the reagent to form insoluble immune complex. Compared with the traditional turbidimetric method, the turbidity of the immune complex is further amplified due to the coated polystyrene particles, which overcomes the disadvantage that it is difficult to form turbidity when the amount of antigen-antibody complex is small, improves the sensitivity of detection, meets the requirements of rapid reaction and micro quantization, and is suitable for automatic biochemical instrument detection. Latex immunoassay is not only simple and rapid, but also can be automated, suitable for batch detection, and the reagent cost is relatively low, is one of the best choice of laboratories with automatic biochemical instrument to carry out PCT detection, has a wide range of application prospects.

Lateral flow test principle is in the 1990 s in monoclonal antibody technology, colloidal gold immune chromatography technology and new materials technology developed on the basis of a new type of in vitro diagnostic technology, is fast, simple, single copy detection and economic advantages, has been widely used in medical tests, food quality monitoring, environmental monitoring, agriculture and animal husbandry, entry-exit inspection and quarantine, forensic finalized and other fields. With the rapid development of immune detection technology, quantitative, high-sensitivity, multivariate detection and system integration have become a new research focus in the field of IVD. Compared with traditional ELISA and colloidal gold qualitative lateral chromatography, lateral flow test has many advantages, such as good stability, wide linear range and high sensitivity.

Immunological detection method is a series of experimental methods for the determination of antigens, antibodies and immune cells. With the interdisciplinary infiltration, the scope of immunology is expanding, and new immunological detection methods are emerging one after another. The application of IVD assay is also expanding, which not only becomes an important method for the diagnosis of a variety of clinical diseases, but also will continue to provide convenience for the research of many disciplines.