The NOD2 receptor does not play a major role in the pathogenesis of Group B Streptococcus in mice

• The role of NOD2 receptor in Group B Streptococcus infection was evaluated in vivo.
• Infected NOD2−/− mice showed reduced production of inflammatory cytokines.
• Even so, absence of NOD2 receptor does not affect mouse susceptibility to infection.

Group B Streptococcus (GBS) capsular type III is an important agent of life-threatening invasive infections. It has been previously shown that encapsulated GBS is easily internalized by dendritic cells (DCs) and this internalization has an impact on cytokine production. The intracellular receptors or pathways underlying this response are not well understood. In this work, we investigated the role of NOD2 in the pathogenesis of GBS using a mouse model of infection. NOD2−/− mice showed similar levels of survival and bacteremia than control mice. Interestingly, ex vivo analysis of total spleen cells from infected animals showed that the absence of NOD2 results in reduced production of inflammatory cytokines. However this abridged inflammatory response does not seem to improve mouse survival. In conclusion, we demonstrated that NOD2 is not a crucial receptor to fight GBS infection and only partially contributes to the inflammatory response.