BCG vaccination provides protection against IAV but not SARS-CoV-2. Kaufmann et al.
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Table S1 Dataset for Manuscript Kaufmann, Khan, et al., Cell Reports, 2021: BCG vaccination provides protection against IAV but not SARS-CoV-2 Summary Since the vast majority of species solely rely on innate immunity for host defense, it stands to reason that a critical evolutionary trait like immunological memory evolved in this primitive branch of our immune system. There is ample evidence that vaccines such as Bacillus Calmette-Guerin (BCG) induce protective innate immune memory responses (trained immunity) against heterologous pathogens. Here we show that while BCG vaccination significantly reduces morbidity and mortality against influenza A virus (IAV), it fails to provide protection against SARS-CoV-2. In contrast to IAV, SARS-CoV-2 infection leads to unique pulmonary vasculature damage facilitating viral dissemination to other organs, including the bone marrow (BM), a central site for BCG-mediated trained immunity. Finally, monocytes from BCG-vaccinated individuals mount an efficient cytokine response to IAV infection, while this response is minimal following SARS-CoV-2. Collectively, our data suggest that the protective capacity of BCG vaccination is contingent on viral pathogenesis and tissue tropism.