Natural antibodies to polysaccharide capsules enable Kupffer cells to capture invading bacteria in the liver sinusoids.

ABSTRACT: The interception of blood-borne bacteria in the liver defines the outcomes of invasive bacterial infections, but the mechanisms of this antibacterial immunity are not fully understood. This study shows that natural antibodies (nAbs) to capsules enable liver macrophage Kupffer cells (KCs) to rapidly capture and kill blood-borne encapsulated bacteria in mice. Affinity pulldown with serotype-10A capsular polysaccharides (CPS10A) of Streptococcus pneumoniae (Spn10A) led to the identification of CPS10A-binding nAbs in serum. The CPS10A-antibody interaction enabled KCs to capture Spn10A bacteria from the bloodstream, in part through complement receptors on KCs. The nAbs were found to recognize the β1-6-linked galactose branch of CPS10A and similar moieties of serotype-39 S. pneumoniae and seroty

SUBMITTER: Tian X 

PROVIDER: S-EPMC11668174 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature