P1 functions as TLR2 agonist – with major contribution of RrgA D3 – in human epithelial cells. Rekombinant RrgA oligomers show increased TLR 2 activation. RrgA D3 is involved in pneumococcal mediated TLR2-activation, TNF-α induction and virulence in a mouse model of infection. Here, TLR2 is linked to infection.