The conjugate formed is then recognized as a foreign body by the Langerhans cells (LCs) (and in some cases other Dendritic cells (DCs)), which then internalize the protein; transport it via the lymphatic system to the regional lymph nodes; and present the antigen to T-lymphocytes. This process is controlled by cytokines and chemokines – with tumor necrosis factor alpha (TNF-α) and certain members of the interleukin family (1, 13 and 18) – and their action serves either to promote or to inhibit the mobilization and migration of these LCs.[15] As the LCs are transported to the lymph nodes, they become differentiated and transform into DCs, which are immunostimulatory in nature.