 Non-specific phagocytosis eliminates entire cells through the process of phagocytosis, aka endocytosis, aka yumpsualization. So non-specific phagocytosis is carried out by three main types of cells, and those are the macrophages. The first one surprises you, macrophages. Also by the neutrophils, neutrophils, and these are white blood cells. And the last group is the one, the last guy, the last player, the last non-specific phagocyt, is a dendritic cell, and I didn't... The impression is that dendritic cells are white blood cells, and every time we talk about, like, why don't we learn about dendritic cells when we do white blood cells in anatomy? I don't know, and so I'm wondering why they're weird. Maybe you... they don't live in the blood for very long, so they're white blood cells that then would head into the tissues and do their job of patrolling. Dendritic cells engage in this non-specific phagocytosis, and I'll tell you how this process works, but then they are required to activate T-cells. So part of your acquired immune response is totally dependent on dendritic cells doing this process. So you should probably be wondering, like, how do they know? There has to be a way for these phagocytes to know when a bad guy is a bad guy versus when it's just, you know, one of your cells that maybe has gone rogue, whatever. How do you know? And here's the thing, are phagocytes. So this is one of these cells. They have special receptors on their, like, embedded in their cell membrane, and they're called pathogen, no, pattern, recognition, recognition receptors, also known as PRRs. So pattern recognition receptors are embedded in my phagocyt. These are general patterns that match molecules that are known as PAMPs, okay? So just second, a PAMP is a pathogen-associated molecular marker. So who would a PAMP be attached to? A pathogen. So I'm going to give you an example of a PAMP. So it would be peptidoglycan, peptidoglycan. And this is a molecule that is often used to build a bacterial cell wall. In fact, bacteria that stain gram positive, those of y'all who've had micro or who are in micro, the peptidoglycan is something that our non-specific phagocytes can actually recognize. So if you get invaded by a gram positive bacteria that has peptidoglycan, your non-specific phagocytes are going to be able to deal with that without having to initiate any kind of crazy cascade response, which we're going to learn all about in the next lecture with the acquired immune response. So it's pretty awesome. It's fast. And there's other PAMPs that ultimately make it so that these guys can yumstralize or endocytose the entire thing. Now, after they endocytose it, they, you would end up with this bacteria inside or this bad guy inside with this little marker. And do you agree that if I ended up with this guy inside, I actually would have only gotten in there because I would have endocytosed it? Do you see what I just did? Okay, say yes. You totally know what I just did. Like I didn't gulf that whole thing. And now I've got it in this little vesicle. And then I can totally digest the holy living tar out of it. That's part of the battle of holy living tarnis. And I'm going to break it all up into little pieces and then this is so cool. Then I can actually, I can do multiple things. I can just like use it for parts. It's awesome. Or I can post its body parts on my Facebook page and say, hey, look at what I just killed. This thing's awesome. I just killed it. And because cells do have Facebook pages. You didn't know that, did you? They do. You know what that is? It's called an MHC platform. And guess what? It might be one of the only reasons. Well, I mean, I get pretty fired up about all sorts of battle analogies. That's pretty fun for me. But the idea of your cells having Facebook platforms that they like tell you what they're doing and what they've been doing and who they ate. Dude, that alone is reason enough to teach the immune system in my classes. So let's go learn about this Facebook platform that I speak of, this major histo-compatibility complex. K.