<prompt> Most potent stimulator of naive Tcells?Mature dendritic cellsFollicular dendritic cellsMacrophagesB cell  <response>: Ans. is a i.e., Mature dendritic cells . Mature B cells and T-cells before antigenic exposure are called naive B and T cells respectively. Sequence of events in activation of naive T cells : . Immature dendritic cells in the epidermis are called langerhans cells. . These immature dendritic cells langerhans cells capture the antigen in the epidermis. . After capturing the antigen, these cells secrete cytokines. . These cytokines cause loss of adhesiveness of langerhans cells. . Langerhans cells separate from each other and migrate to lymphatic vessels. . In lymphatic vessel, maturation of langerhans cells takes place. . Then these mature langerhan dendritic cells reach to naive T cells in the lymph nodes and present antigen to these cells and activate them. 