New insight on immunological activation pathways of Langerhans cells, possible tolerogenic role

Langerhans cells are the prototype of antigen presenting cell, their role is to work as sentinel in the epidermis. Like every APC Langerhans cells act as bridge between innate and acquired immunity recognizing antigens into the epidermis and bringing them to drying lymph node, their work is well described by the Langerhans cell paradigm. Recently many works designed a new and amazing role of Langerhans cells in fact they often showed tolerogenic capacity, while in many cases, they seems not necessary to promote activation of acquired immunity. Anyway Langerhans cells remaining an interesting target for new vaccine strategies because of their localization in the epidermis and the ability to capture antigens trough different recognition pathways. Also interesting is the possible use of langerhans cells for their tolerogenic capacity, in many experimental models these cells opportunely addressed with appropriated cytokines appears able to down-regulate immune system response in autoimmune pathology.