B Cells - The Players In The Immune System : Part 3

UltraLongevity: The Seven-Step Program for a Younger, Healthier You
By Mark Liponis, M.D.

(Page 3 of 5)

One example of an overreaction by our immune system is an allergy, which can trigger serious problems like asthma or even anaphylaxis, which can be lethal. We'll talk more about this later. B cells possess another important function. They make antibodies, whose role in your internal homeland security is similar to that of the U.S. Army Corps of Engineers. Here B cells work closely with T cells to build complex mechanical and chemical structures that act as deadly weapons to neutralize invaders.

Antibodies are complex proteins manufactured to exact specifications. Each antibody is built by the B cells to neutralize one specific invader. Medical science does not yet fully understand the way in which these antibodies are made. What is known is that B cells team up with macrophages in order to create them.

First, what is a macrophage? Phage comes from the Greek phagon, meaning "to eat." Macro, from the Greek macron, means "big." Thus a macrophage is a "big eater."

Macrophages constantly patrol the body, which means they can be considered your body's military police, or MPs. The MPs are constantly on the lookout, in every organ in your body. Always moving, they crawl between the trillions of cells in all of your organs like an amoeba might crawl across a petri dish.

These bloblike, voracious eaters are searching for any invaders that might have sneaked into your body. When an MP encounters one, it will capture it, cut it up into a thousand tiny pieces, and then take the bits and show them around the body to let the other troops, such as the B cells, know exactly what the invader looks like.

Sound overly dramatic? Actually, it's quite close to the literal truth. When macrophages encounter an invader, they grab it with amoebalike fingers and engulf it, swallowing the invader whole so that it becomes a captive. The macrophage then releases enzymes to digest it, breaking it down into tiny bits. These little sections become pieces of proteins-small enough to be moved around but large enough to provide a unique "fingerprint" identifying the invader the MP just gobbled up and digested.

The MP next spits up these little digested bits of protein fingerprints and displays them on its own surface, similar to placing a "Wanted" poster for the rest of your immune system to see. Now the B cells move in, going up to that "Wanted" poster, or that piece of the invader, and learning its shape. They then build an antibody that suits the shape of the invader perfectly. This antibody can now recognize and attach itself to the invader the next time it comes into contact with it.

The B cells next start making millions and millions of copies of this antibody, releasing them into the bloodstream. They fl oat through our blood, and if they come into contact with one of these microbial invaders, the antibodies immediately attach themselves to it, triggering a series of events that will ultimately kill it.

Our B cells manufacture antibodies to exceptionally tight specifications so that the antibodies are specific to one particular germ. And the antibodies must be a perfect fit; otherwise, critical problems would result, the most important being that the antibody might not be properly able to recognize and neutralize the threat.

If, for instance, the antibody mistakenly grabbed onto your eye, you would go blind. If it grasped your brain, you'd suffer brain damage. As soon as antibodies take hold of something, a chain reaction is produced, and that thing will either be neutralized or killed.

Once a B cell learns to produce an antibody with the help of a macrophage, it retains the memory to produce that antibody forever. So in effect, that B cell is forever programmed to recognize a specific invader. If it ever encounters that invader again, the B cell will immediately begin producing millions of copies of its antibody, and will also reproduce itself thousands of times to create a force of so-called daughter cells. Each daughter cell also inherits the know-how to recognize that specific invader and to produce its specific antibody.

It is thought that B cells live anywhere from about a year to about six years. B cells reproduce themselves (by cell division) to maintain their collective memory, which is crucial for your very survival. And B cells can also multiply quickly in response to the recognition of a known threat. This ability to multiply helps build a formidable antibody response in the event a known invader gains entry into your body again.

There's a lot of brainpower in the B cells.

© 2007 by Mark Liponis, MD

About the Author

Mark Liponis, MD, is the medical director of the Canyon Ranch Spa in all its locations. He is the coauthor of New York Times bestseller UltraPrevention, which won the 2003 Books for a Better Life Award in the health category.