Neisseria meningitidis expressing lgtB lipopolysaccharide targets DC‐SIGN and modulates dendritic cell function

Summary Neisseria meningitidis lipopolysaccharide (LPS) has been identified as a major determinant of dendritic cell (DC) function. Here we report that one of a series of meningococcal mutants with defined truncations in the lacto‐N‐neotetraose outer core of the LPS exhibited unique strong adhesion and internalization properties towards DC. These properties were mediated by interaction of the GlcNAc(β1‐3)‐Gal(β1‐4)‐Glc‐R oligosaccharide outer core of lgtB LPS with the dendritic‐cell‐specific ICAM‐3 grabbing non‐integrin (DC‐SIGN) lectin receptor. Activation of DC‐SIGN with this novel oligosaccharide ligand skewed T‐cell responses driven by DC towards T helper type 1 activity. Thus, the use of lgtB LPS may provide a powerful instrument to selectively induce the desired arm of the immune response and potentially increase vaccine efficacy.