| First Author | Hilligan KL | Year | 2022 |
| Journal | J Exp Med | Volume | 219 |
| Issue | 2 | PubMed ID | 34889942 |
| Mgi Jnum | J:335921 | Mgi Id | MGI:6854693 |
| Doi | 10.1084/jem.20211862 | Citation | Hilligan KL, et al. (2022) Intravenous administration of BCG protects mice against lethal SARS-CoV-2 challenge. J Exp Med 219(2) |
| abstractText | In addition to providing partial protection against pediatric tuberculosis, vaccination with bacille Calmette-Guerin (BCG) has been reported to confer nonspecific resistance to unrelated pulmonary pathogens, a phenomenon attributed to the induction of long-lasting alterations within the myeloid cell compartment. Here, we demonstrate that intravenous, but not subcutaneous, inoculation of BCG protects human-ACE2 transgenic mice against lethal challenge with SARS-CoV-2 (SCV2) and results in reduced viral loads in non-transgenic animals infected with an alpha variant. The observed increase in host resistance was associated with reductions in SCV2-induced tissue pathology, inflammatory cell recruitment, and cytokine production that multivariate analysis revealed as only partially related to diminished viral load. We propose that this protection stems from BCG-induced alterations in the composition and function of the pulmonary cellular compartment that impact the innate response to the virus and ensuing immunopathology. While intravenous BCG vaccination is not a clinically acceptable practice, our findings provide an experimental model for identifying mechanisms by which nonspecific stimulation of the pulmonary immune response promotes host resistance to SCV2 lethality. |
