It basically eats up and digests different types of pathogens that are found inside our blood inside these specialized masses of tissue we call lymph nodes. Now, the final portion that I'd like to focus on is how that fluid actually gets into these lymph vessels in the first place and how the limb travels along our limb vessels. So let's take a look at the following diagram. So this is a small portion of our lymph vessel. Now, notice along the lymph vessel, we have these endothelial cells. So the walls of the lymph vessels consist of endothelial cells that overlap slightly.