Blog Two: 3/20, Antibodies to Antigens, Macrophages to Memory Immune Cells, and All In Between!

Posted 3/19

 Alright! I have finished reading Immune: A Journey Into the Mysterious System that Keeps You Alive! It was a great book, with wonderful graphics, easy-to-understand analogies, and a great place to start learning about such a wonderful science; I would definitely recommend this book to anyone and everyone, looking to find a way to get interested in more advanced sciences, like immunology. My guess is that the easier-to-understand aspects of this book will fill up most of what I put into my presentation, with references to the deeper immune science. 

Well, enough with the book report: let us get into everyone's favorite section: The Science! 

Interestingly, the Immune System (I may refer to it as the IS) is actually split into two different sections: the Innate Immune System (IIS), and the Adaptive Immune System (AIS). The Innate Immune System is the first responders in any immune battle. They are like the ambulances that show up when a large amount of people get hurt. When you cut your skin, the bacteria which constantly sits on you skin floods into your innards, as your insides are nice, warm, enticing places to reproduce as comparison to your dry, very slightly acidic skin. but when they invade, they also start to kill civilian cells. 

So imagine a hundred thousand serial killers with weapons being let into a room full of trillions of innocent civilians. Of course, this is a great big dilemma, but the civilian cells don't go down without a battle. When the cell dies, it sends out a special protein called a Cytokine. Think of this as the last thing this cell does as it collapses is that it pulls out its phone and calls 911. Now the Cytokines would be like the phone call traveling through the phone lines, your veins, to your immune system cells.  In this case, your innate immune system cells act as both the 911 call operator, and the police/ambulance/firefighter. Now of course, the more "phone calls" received, the more "first responders" respond the situation. There are two main IIS cells, which are the macrophage, and the neutrophil. The macrophage is like the police officer which come in, and breaks down the situation, and reduced the violence; macrophages defeat bacteria by engulfing the bacteria using their own membrane, and then breaking the bacteria down and letting out the waste. The neutrophil, on the other hand, is kind of like a ball with a bunch of spikes on its ends, and eliminate a bunch of the bacteria, but on the other hand will also end up killing some civilian cells. 

While the IIS is known for responding instantly, within minutes if not seconds, there is another trick up the IS's sleeve: the Adaptive Immune System. You know when you get sick, it usually takes a couple days for your body to defeat it? Well if the IIS are first responders, the AIS is like the FBI or the National Guard of your body when things get serious. When your IIS destroys bacteria, the remnant parts of this bacteria are now antigens. Antigens are then found and collected by another new cell, the dendritic cell. The dendritic cell is kind of like a huge jellyfish, it has dozens of arms, each with dozens of receptors to catch these antigens. Then, the dendritic cells now go into the lymphatic system.

 The lymphatic system is commonly known for the purpose of flushing out all the mucus and waste products of the body, which is the perfect place for T-cells and B-cells to chill, waiting to be activated. I already talked about T-cells in my first blog, but as a recap, the T-cells cycle around the lymphatic system waiting for that one antigen, to go into super-saiyan-mode, boosting your IIS to work for it again. 

Now, I also want to bring up B-cells. If T-cells are the foot-soldiers, the B-cells are the commandoes. They are so powerful, that they require a two-factor-authentication to start actually producing what they produce, the antibodies. First, the B-cell has to find one of the T-cells that also are specialized against the virus, as well as finding its own antigen. Once this happens, well, all hell breaks loose. B-cells start producing antigens at about 2,000 per second each! Outstanding! Once this happens, for smaller infections, it is game over: the antibodies bind and maim the virus or bacteria to the point where it becomes easy as pie for the macrophage to pick them up and break them down. 

Whoosh, a lot of info for a pretty short time. So, in a nutshell, the innate immune system is the first responders that start fighting the infection right away, and it may not be as strong, and the adaptive immune system shows the true power of the dark side the immune system, and most common viruses are defeated within a day or two. The next time we meet up again, I will have read An Elegant Defense, and had 4 intriguing real stories to tell. 

Edit: I have commented on Stephan, Parth, and Charles's blogs.