And these cytotoxic T cells contain the glycoprotein CD eight, CD eight. And we'll see exactly what that means in just a moment. So let's take a look at these plasma cells. So these plasma cells have very extensive endoplasmic reticulum as seen in the following diagram. And that's because these plasma cells, their function is to basically form antibody. So remember, the plasma cells and the memory B cells are part of the humoral immunity, they're part of the antibody mediated immunity.