Abstract: Provided are a method for assaying a specific IgM antibody and a total antibody for the 2019 novel coronavirus (2019-nCOV), a method for determining whether subjects are infected with 2019-nCOV, and a virus antigen and a kit for carrying out the above-mentioned detection.

Abstract: Disclosed are a fusion protein probe and a cell model for screening a blocking agent of coronavirus infections, a screening system comprising same, and a method of using the screening system for screening a blocking agent of coronavirus infections. The screening system and method do not involve live viruses, are simple and convenient to operate, have a high accuracy, are suitable for high throughput screening, and are of great significance for the development of coronavirus neutralizing antibodies, preventive vaccines, and small molecule drugs.

Abstract: 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.