Antimicrobial peptides are important components of the innate immune system. Beside their antimicrobial functions they play an important role in modulating an inflammatory reaction. In this study we report that pre-stimulation of monocytes and macrophages with the β-defensin HBD2 results in a synergistic, enhanced expression of pro-inflammatory cytokines induced by TLR ligand re-stimulation. Thereby, HBD2 indirectly interacts with the P2X7R by the release of ATP.
In addition we generated a hReg3α transgenic mouse line. The overexpression of hReg3α resulted in an altered gut microbiota composition, which negatively affected the regeneration after a DSS-induced colitis. The expression of hReg3α induced an enhanced tumor growth in the examined tumor model.