What is the immune system?

What is the immune system? What is the immune system? One of the most broad questions there is. Well, the immune system is a collection of different cells and parts of the body that all work together to prevent bad things. And I know that sounds kind of general, but the immune system is designed to prevent all bad things ranging from viruses and bacteria all the way up to cancer. And at least the way that I can sexualize the immune system is like the armed forces. We have some special forces of people who have decades of training and snipers, but we also have the men and women on the front line fighting everyone. And NK cells are like the front line warriors, and B cells and T cells may be a little more like special forces. They've been particularly trained for a particular different enemy. And this is really important because our body makes cancer cells 24 hours a day, and our immune system is designed to say, okay, you're cancer, go kill yourself. And it's really designed to hold that under control. And what happens sometimes is if those cancer cells grow just big enough, they're not good enough to attack, and it overcomes our immune system, we get cancer. And that's what's really changing our approach to treatment nowadays. We used to give classical chemo and just kill everything. Now we realize, no, the immune system's already fighting. Maybe we just need to bring more of them in. So a CAR T cell is just collecting a couple of parts of your immune system, giving them special training, multiplying them and putting them back in your system, like calling in dozens and dozens of special forces. Or by specific antibodies that tell a couple people that have been fighting for a while who are getting a little tired, hey, wake up, come on, we got to win this. So it's a complex interaction of lots of different cells that communicate with one another, that fight off a variety of things, literally all the way from a little sniffle to the worst type of cancer.