A conserved antigen induces respiratory Th17-mediated broad serotype protection against pneumococcal superinfection

Cell Host Microbe. 2024 Feb 21:S1931-3128(24)00037-4. doi: 10.1016/j.chom.2024.02.002. Online ahead of print.ABSTRACTSeveral vaccines targeting bacterial pathogens show reduced efficacy upon concurrent viral infection, indicating that a new vaccinology approach is required. To identify antigens for the human pathogen Streptococcus pneumoniae that are effective following influenza infection, we performed CRISPRi-seq in a murine model of superinfection and identified the conserved lafB gene as crucial for virulence. We show that LafB is a membrane-associated, intracellular protein that catalyzes the formation of galactosyl-glucosyl-diacylglycerol, a glycolipid important for cell wall homeostasis. Respiratory vaccination with recombinant LafB, in contrast to subcutaneous vaccination, was highly protective against S. pneumoniae serotypes 2, 15A, and 24F in a murine model. In contrast to standard capsule-based vaccines, protection did not require LafB-specific antibodies but was dependent on airway CD4+ T helper 17 cells. Healthy human individuals can elicit LafB-specific immune responses, indicating LafB antigenicity in humans. Collectively, these findings present a universal pneumococcal vaccine antigen that remains effective following influenza infection.PMID:38417443 | DOI:10.1016/j.chom.2024.02.002
Source: Cell Host and Microbe - Category: Microbiology Authors: Source Type: research