Escherichia coli maltose-binding protein (MBP) activates mouse Th1 through TLR2-mediated MyD88-dependent pathway and TLR4-mediated TRIF-dependent pathway.

MBP (maltose-binding protein) is a component of Escherichia coli. Our previous study found that MBP directly induces the activation of Th1 (T helper type 1), but the molecular mechanism remains unclear. In the present study, CD4T cells were purified from the spleens of normal mice using antibody-coated immunomagnetic beads by negative selection.

The Combination of MBP and BCG-Induced Dendritic Cell Maturation through TLR2/TLR4 Promotes Th1 Activation In Vitro and Vivo.

To explore whether TLR2/TLR4 could be involved in the maturation of dendritic cells and polarization of CD4 T cells induced by dendritic cells stimulated with MBP and BCG, in vitro and in vivo experiments using TLR2 or TLR4 mice were employed. MBP and BCG elevated CD80, CD86 and MHC class II expressed on dendritic cells and increased IL-12 protein, induced DC maturation, and indirectly promoted Th1 activation. Moreover, MBP and BCG upregulated costimulatory molecules on DCs in a TLR2- and TLR4-dependent manner.

Escherichia coli Maltose-Binding Protein Induces M1 Polarity of RAW264.7 Macrophage Cells via a TLR2- and TLR4-Dependent Manner.

Maltose-binding protein (MBP) is a critical player of the maltose/maltodextrin transport system in Escherichia coli. Our previous studies have revealed that MBP nonspecifically induces T helper type 1 (Th1) cell activation and activates peritoneal macrophages obtained from mouse. In the present study, we reported a direct stimulatory effect of MBP on RAW264.