The Immune Enhancing Effects of Tea: Theanine

Mammals have two largely independent immune systems in their bodies. Although these immune systems do interact, they serve two very different roles in protecting us against pathogens, including cancer and infectious diseases.

Most people are generally familiar with the immune system that is activated by vaccines. This immune response is highly specific, but it is also very slow to respond to specific pathogens. This is why vaccines exist... to pre-activate this genetic or adaptive immune response to specific pathogens. The faster an immune response can be mounted against a specific pathogen, the more immunological protection it provides.

Herein lies the problem. If a person has never been exposed, for example, to a particular influenza virus strain, the specific immune response to this virus may be too slow to protect us against death. This is why flu vaccines are changed every year. The key word is specificity. Yesterday's flu virus may not protect us from Bird Flu or another influenza strain.

Yet, there is another immune system that MAY protect us against All strains of Flu or other pathogens without vaccines.

Think about it. If we HAD to be vaccinated against all pathogens that we encounter, every child over 2 years of age would be dead. Every watch a child eat dirt or stick a dirty object into their mouths? Yet these children do NOT die. There is a reason for this.

Our secondary immune system is called the innate or natural immune system. It encompasses a wide diversity of cells, including natural killer cells, gamma delta T lymphocytes, neutrophils and macrophages. This system is our first line of immunological defense against cancer, and infectious pathogens. Usually, this immune response works just fine. If it didn't, no one would survive childhood.

These immune cells are not activated by immunization. They have the magical ability to recognize and react to the presence of pathogens, including cancer cells, by non-specific means. If you read the scientific literature, it is simply amazing how the innate immune response works and how effective it is in protecting us from...well just about everything.

Although we can activate the genetic immune system by vaccination, can we do the same with the innate or natural immune response? Apparently so.

Three years ago, a scientific study published in the prestigious Proceedings of the National Academy of Sciences made the news throughout America. Theanine, an amino acid which is 50% of the dry weight of tea leaves, was found to prime a major component of our innate immune system, gamma delta T lymphocytes. Finally, a natural immune enhancer.

This article can be read online if you are interested.

Gamma delta T cells are a special population of immune cells that increase by 50 fold when we are confronted with bacteria, fungi and viruses. Theanine primes these lymphocytes so they can immediately respond if confronted with a bacterial, fungal or viral infection.

Interestingly, this study shows that drinking green or back tea increases immune reactivity to recall antigens. Recall antigens are simply bacterial, fungal or viral products to which we have been previously exposed. In the presence of theanine breakdown products, our immune system rapidly responds to these pathogens if we encounter them again. The faster our immune system reacts, the more protection it provides us. So drink your tea on a regular basis or take some theanine capsules, sold in health food stores.

In the last year, scientists found that this very same population of gamma delta T cells was much more important for our immunological well being than we previously recognized.

Gamma delta T cells, once activated or primed (by theanine?) can further activate our normal alpha beta T cells, CD4 and CD8 T cells which produce antibody and attack cancer and virally infected cells. These cells act like APC or antigen presenting cells, much like dendritic cells.

This study was published in the prestigious journal Science.

In the past, no one has ever linked the activation to our genetic immune response to innate immune responses. This study shows that both our immune responses are interrelated. If the gamma delta T cells of our innate immune response can be activated by metabolites of theanine from tea, these cells can further activate our genetic immune response, including the production of specific antibody and cellular immune responses against cancer cells, virally infected cells and other pathogens. And that ain't bad!!!

In a world paralyzed by fears of Bird Flu, cancer and other pathogens, it is important that we keep our immune systems primed. So learn to love tea or take theanine supplements.

Not everything in life has to be complicated.

Copyright 2006 Grouppe Kurosawa

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About The Author, Dr. Stephen Martin
Dr. Stephen Martin is the Chief Scientist of Grouppe Kurosawa, Medicine in the Public Interest. Grouppe Kurosawa is dedicated to establishing Free treatment protocols for a host of acute and chronic diseases using only natural medicines, supplement products and generic drugs.