Gp120

Okay, so you know how when you open a door, you need a key to unlock it? Well, the same thing happens in our body when different cells need to talk to each other and do stuff together.

But instead of a key, they use a kind of keyhole called a receptor. And one of the cells in our body, called the immune cell, has a specific receptor called CD4 that helps it talk to other cells and fight off germs that make us sick.

But there's a tricky little virus called HIV that tries to invade our immune cells and make us really sick. And the way it does this is by using something called gp120.

Now, gp120 is like a disguise that the HIV virus wears when it tries to enter our immune cells. It's like putting on a really good Halloween costume and pretending to be someone else. So when the HIV virus wears gp120, it can sneak into our immune cells without being recognized as a bad guy.

But don't worry, our immune cells are pretty smart too. They have other receptors that can spot the trickery and warn the rest of the immune system to attack the virus before it can make us sick.

So, even though gp120 is a sneaky and dangerous part of the HIV virus, our immune cells are ready to fight back and keep us healthy.