Research progress on specific and non-specific immune effects of BCG and the possibility of BCG protection against COVID-19

Jingli Du; Yue Su; Ruilan Wang; Enjun Dong; Yan Cao; Wenjuan Zhao; Wenping Gong

doi:10.3389/fimmu.2023.1118378

Research progress on specific and non-specific immune effects of BCG and the possibility of BCG protection against COVID-19

Front Immunol. 2023 Jan 31:14:1118378. doi: 10.3389/fimmu.2023.1118378. eCollection 2023.

Authors

Jingli Du¹, Yue Su¹, Ruilan Wang¹, Enjun Dong¹, Yan Cao¹, Wenjuan Zhao¹, Wenping Gong¹

Affiliation

¹ Tuberculosis Prevention and Control Key Laboratory/Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Senior Department of Tuberculosis, The 8th Medical Center of PLA General Hospital, Beijing, China.

Abstract

Bacille Calmette-Guérin (BCG) is the only approved vaccine for tuberculosis (TB) prevention worldwide. BCG has an excellent protective effect on miliary tuberculosis and tuberculous meningitis in children or infants. Interestingly, a growing number of studies have shown that BCG vaccination can induce nonspecific and specific immunity to fight against other respiratory disease pathogens, including SARS-CoV-2. The continuous emergence of variants of SARS-CoV-2 makes the protective efficiency of COVID-19-specific vaccines an unprecedented challenge. Therefore, it has been hypothesized that BCG-induced trained immunity might protect against COVID-19 infection. This study comprehensively described BCG-induced nonspecific and specific immunity and the mechanism of trained immunity. In addition, this study also reviewed the research on BCG revaccination to prevent TB, the impact of BCG on other non-tuberculous diseases, and the clinical trials of BCG to prevent COVID-19 infection. These data will provide new evidence to confirm the hypotheses mentioned above.

Keywords: Bacille Calmette-Guerin (BCG); COVID-19; specific and non-specific immunity; trained immunity; tuberculosis (TB).

Publication types

Review
Research Support, Non-U.S. Gov't

MeSH terms

BCG Vaccine
COVID-19 Vaccines
COVID-19* / prevention & control
Child
Humans
Immunization, Secondary
Infant
SARS-CoV-2
Tuberculosis* / drug therapy
Tuberculosis* / prevention & control

Substances

BCG Vaccine
COVID-19 Vaccines

Grants and funding

This study was funded by the Special Research on Health and Epidemic Prevention (Grant No. 22FYFH02) and Beijing Municipal Science & Technology Commission (Grant No. 7212103 and L192065).