So let's suppose some type of foreign antigen is found inside our tissue and it comes from, let's say, some type of bacterial cell, the same cell that we spoke of earlier. Now, what this centring cell does is it basically phagocytizes this antigen and it basically engulfs it. And the lysosomes break it down and a small part of it is then expressed, it's then displayed on this MHC class Two complex that is formed by the cell as shown in the following diagram. Now, the dendritic cell is motile. And what that means is it can then move into the spleen or the lymph nodes of our immune system and it basically begins to interact with some type of T lymphocytes that once again has the CD four glycoprotein, the proper T cell receptor found on the membrane of that T lymphocyte. And when these two cells interact once again it elicits some type of defensive immune response.