WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, Tsinghua University - Center for Global Health and Infectious Diseases, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, WHO Collaborating Center for Standardization and Evaluation of Biologicals, Tsinghua University - Center for Global Health and Infectious Diseases, WHO Collaborating Center for Standardization and Evaluation of Biologicals, Government of the People's Republic of China - Division of HIV/AIDS and Sex-transmitted Virus Vaccines and WHO Collaborating Center for Standardization and Evaluation of Biologicals