Semaphorins were identified originally as guidance cues for developing neuronal axons. However, it is becoming clear that several semaphorins play important roles in the immune system. For instance, Sema4D (CD100) enhances activation of B cells and dendritic cells through its receptor, CD72. Sema4A is crucially involved not only in T cell priming but also in Th1/Th2 regulation. Additional semap...

Mesenchymal stem cells are present within the bone marrow cavity and serve as a reservoir for the continuous renewal of various mesenchymal tissues. Recent studies suggest that mesenchymal stem cells modulate immune reactions in vitro and escape from immune surveillance in vivo. We provide herein a discussion of issues including the current research progress on the in vitro interactions of mese...

transforming growth factor beta (tgf-b) is a mediator released by nearly all cell types. it has suppression activity on the immune system, but exactly how this effect is carried out is not clear. previous experiments showed that igg interacts with or carriers active tgf-b, that could suppresses cytotoxic t-cell responses to an immunogenic tumor in mice. since t cell receptor (tcr) has structura...