Langerhans Cells

The Langerhans cells are specialised in activating dormant T-helper cells and thus initiating a primarily T-cell-dependent immune response. They play an important role in contact allergic, skin transplant rejections and other immunological processes of the skin.

After contact with the corresponding antigen (viruses, contact allergens, skin grafts), the Langerhans cell leaves the epidermis and reaches a [[lymph node] via the lymph flow.] In this way it undergoes a maturation process that leads to the presentation of the antigen on the cell surface. The emigrating cells are replaced by a corresponding number of new Langerhans cells from the bone marrow.

In the lymph node, the Langerhans cells matured in this way activate T-helper cells, which in turn have suitable antigen-specific receptor on their surface. They thus initiate the reaction of the systemic immune system.