Lactic acid bacteria secrete toll like receptor 2 stimulating and macrophage immunomodulating bioactive factors

Chengcheng Ren, Lianghui Cheng, Yue Sun, Qiuxiang Zhang, Bart J. de Haan, Hao Zhang, Marijke M. Faas, Paul de Vos
2020 Journal of Functional Foods  
A B S T R A C T Lactic acid bacteria (LAB) can support host health and crosstalks between ligands on bacterial cells and Toll-like receptors (TLR) are known as key inducers of these health effects. LAB-secreted bioactive factors also possess health-promoting properties but the underlying mechanisms remain to be identified. Here, we report that secreted factors of different LAB strains induce cytokine (IL-10 and TNF-α) production by THP1-differentiated human macrophages in a species-and
more » ... pendent manner. LAB-secreted products also drive immunestimulating and anti-pathogenic M1-macrophage polarization. Moreover, bacterial supernatants induce speciesand strain-dependent TLR2 activation. Several bacterial strains such as L. casei CCFM9 and L. brevis CCFM498 cannot activate TLR signaling, but their secreted products strongly activate TLR2. This indicates that LAB-secreted components may further boost the functional effects of bacterial strains. Our results confirm direct interactions of LAB-secreted components with TLRs, and provide novel insights in how LABs may provide immunemodulation. These observations suggest that efficient tools need to be developed for https://doi.
doi:10.1016/j.jff.2020.103783 fatcat:mwau3wijwrgxhij3qhplbgfyji