Table 1.
Overview of selected literature on immuno-modulatory and trained immunity effects of BCG.
| Publication | Summary | Organism |
|---|---|---|
| Andersen et al., 2013 | BCG re-vaccination skews the response to PPD towards a Th1 direction, with a greater IFNγ/IL-13 ratio. | Human |
| Arts et al., 2015 | Monocytes from subjects with complete NOD2 deficiency failed to demonstrate trained immunity. | Human |
| Arts et al., 2018 | BCG vaccination produces epigenetic reprogramming of monocytes, and reduces viremia when challenged with the yellow fever vaccine. | Human |
| Eggenhuizen et al., 2021 | BCG protein sequences with homology to SARS-CoV-2 proteins induce enhanced CD4+ and CD8+ T cell responses to SARS-CoV-2 antigens. | Human |
| Jensen et al., 2015 | Infant BCG vaccination enhanced cytokine responses (IL-1β, IL-6, TNF-α, and IFNγ) to heterologous stimulation. | Human |
| Kaufmann et al., 2018 | BCG vaccination affects long-lived cells in the bone marrow and promotes polarization of multipotent progenitor cells towards myelopoiesis at the expense of lymphopoiesis. | Mouse |
| Kleinnijenhuis et al., 2012 | BCG vaccination produces an enhanced cytokine response to heterologous stimulation, mediated by NOD2. | Human |
| Kleinnijenhuis et al., 2014 | Heterologous Th1 responses remain strong for a year following BCG vaccination. | Human |
| Kleinnijenhuis et al., 2014 | BCG vaccination enhances proinflammatory cytokine response to heterologous stimulation. | Human and Mouse |
| Mathurin et al., 2009 | BCG-vaccinated mice’s resistance to vaccinia virus infection was removed by depleting CD4+ T cell populations, suggesting both the innate and adaptive immune components play a role in trained immunity. | Mouse |
| Ugolini et al., 2018 | As a live vaccine, BCG can activate the TLR8 bacterial RNA-detecting PAMP, which regulates TFH cell differentiation and downstream cytokine responses. | Human |
| Urban et al., 2020 | Similarity of T cell and B cell epitopes in the BCG Pasteur strain’s proteome with SARS-CoV-2 peptides may create antigenic cross-reactivity, incorporating adaptive immune response into trained immunity for COVID-19. | Human |
| Uthayakumar et al., 2018 | “Bystander activation” of polyclonal effector T cells by BCG vaccination may reduce their threshold for response when challenged again by heterologous infections. | N/A |
| Wen et al., 2008 | BCG vaccination enhances trimethylation at promoters associated with increased transcription of proinflammatory cytokine genes. | Mouse |