How do dendritic cells form the bridge between the innate and adaptive immune system?

They take up debris and proteins at the site of infection. when they are activated by PAMPs or DAMPs, they release acute-phase cytokines which make them mature. mature DCs cannot take up anything anymore, they move to the lymph nodes. there they upregulate MHC II and present antigens on them and they upregulate CD80, CD86 and CD40 which activate T cells