Klebsiella pneumoniae polysaccharides show vaccine potential

A study found that the O-specific polysaccharide of Klebsiella pneumoniae triggers strong immune responses in patients with bloodstream infections. The responses were significantly higher compared to healthy individuals, indicating its potential as a vaccine target. However, the presence of capsular polysaccharides interfered with antibody binding, limiting the effectiveness of O-specific polysaccharide-based vaccines. The study analyzed 69 patients with infections and 61 controls to assess antibody responses. The research highlights the immunogenicity of O-specific polysaccharides and their cross-reactivity among subtypes. It was published in The Lancet Microbe on February 11, 2025.