Linking innate and adaptive immune system. Dendritic cells from innate immune system present their antigen to naive T cells at local draining lymph nodes. T-cell receptor (TCR) ligation to MHC class II associated peptides processed from pathogens (signal 1) and binding of costimulatory molecule CD28 on lymphocyte to CD80 and CD86 expressed by dendritic cells (signal 2) leads to T-cell lineages differentiation. Signal 3 is the polarizing cytokines signals from the innate immune cells. Depending on type of antigen which is presented and nature of cytokines in the microenvironment, innate DC cells direct the development of Th1, Th2, Th17 lymphocytes lineages which plays crucial role in adaptive immune system.
