ABSTRACT
The BCG vaccine is prepared from a weakened strain of Mycobacterium bovis (M. bovis), a bacterium closely related to Mycobacterium tuberculosis (MTB), which causes tuberculosis (TB). The vaccine was developed over 13 years, from 1908 to 1921, in the French Institut Pasteur by Léon Charles Albert Calmette and Jean-Marie Camille Guérin, who named the product Bacillus Calmette-Guérin (BCG). BCG, the only licensed vaccine currently available to prevent TB, is given to infants at high risk of TB shortly after birth to protect infants and young children from pulmonary, meningeal, and disseminated TB. The BCG vaccine, one of the safest and most widely used live attenuated vaccines in the world, recently celebrated its 100th anniversary (from 1921 to 2021); its record of use in preventing TB in China is also approaching 100 years. In 2022, a new century of BCG vaccine immunization will begin. In this article, we briefly review the history of BCG vaccine use in China, describe its current status, and offer a preliminary outlook on the future of the vaccine, to provide BCG researchers with a clearer understanding of its use in China.
ABSTRACT
The development of an effective vaccine to control the global coronavirus disease-2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus- 2 (SARS-CoV-2) is of utmost importance. In this study, a synthetic DNA-based vaccine candidate, known as pSV10-SARS-CoV-2, expressing the SARS-CoV-2 spike protein was designed and tested in 39 BALB/c mice with BC01, an adjuvant derived from unmethylated CpG motif-containing DNA fragments from the Bacillus Calmette-Guerin genome. Mice vaccinated with pSV10-SARS-CoV-2 with BC01 produced early neutralizing antibodies and developed stronger humoral and cellular immune responses compared to mice that received the DNA vaccine only. Moreover, sera from mice vaccinated with pSV10-SARS-CoV-2 with BC01 can neutralize certain variants, including 614G, 614G + 472 V, 452R, 483A, 501Y.V2, and B.1.1.7. The results of this study demonstrate that the addition of BC01 to a DNA-vaccine for COVID-19 could elicit more effective neutralizing antibody titers for disease prevention.