So the cytotoxic T cells now contain the specific antibody on the membrane that can bind to this specific antigen. And so, when the cytotoxic cell actually comes in close proximity to this type of bacteria that carries that same antigen, this antibody will be able to bind onto that bacteria. And once they are bound, the cytotoxic cell will begin to release these powerful proteins that will drill holes in those bacterial cells, killing off those bacterial cells. Now, we also produce the plasma cells. And what the plasma cells do, they essentially produce those specific antibodies that are complementary, that are specific to this antigen that was found on the MHC class two complex. And so we see that these MHC class II complexes are used by arrow leukocytes, by the white blood cells, to basically communicate between one leukocyte, let's say, the macrophage, and another leukocyte, let's say, the helper T cell, and then that can communicate with other leukocytes, for example, B lymphocytes and T lymphocytes, to produce even more specialized immune cells.