The events which take place when our natural defences (immune systems) try to protect us from germs, viruses, bacteria and other 'enemies' are remarkably similar, visually, to a video game - it could well be called the 'Inner Star Wars' or 'Bloodstream Galactica'.
Our immune system consists largely of two kinds of 'soldier-guard' cells, called T cells and B lymphocytes. The ratio of the two types of cells is important to the normal operation of the immune system. These police officers-cum-border guards are capable of recognising foreign invaders such as bacteria instantly. They propel themselves with considerable force and alacrity towards the 'enemy' which, when bumped into, promptly disintegrates.
The ability to distinguish what belongs to our body and what doesn't is shared by many more micro-organisms than the potentially harmful ones. The immune system will even cause a body to reject perfectly normal proteins if they originated from outside. This rejection is well known as a problem in organ transplants.
When we eat 'foreign' proteins they have to be broken down into single amino acids by the action of special enzymes in the digestive tract. Only then can they be absorbed through the walls of the digestive tract in the form of amino acids. The body goes on to use these as building blocks to resynthesise its own proteins, which are then unique to itself.
Our immune system tends to reject cells from other individuals of the same species. Blood cells are relatively simple because they do not have a nucleus, so that a transfusion does not carry a great risk of rejection if the donor's blood type has been matched to the recipient's. Tissue cells, which have a nucleus, are a different matter altogether and that's why a kidney or heart transplant requires that the immune system of the recipient be literally crippled with immunosuppressive drugs.
We live in a largely hostile environment, surrounded as we are by an incredible array of bacteria, viruses, parasites, mycotoxins and other assorted 'bugs. 'As if an abundant supply of 'natural' enemies such as herpes viruses, staphylococci, chlamydia, lentoviruses, helicobacter pylori, parasites, Candida albicans and more weren't enough, we have spent the last hundred years or so adding a cornucopia of man-made chemicals to our water, air and food.
We all encounter an enormous variety of antigens every day of our lives. In addition to micro-organisms, these can be drugs, animal venoms, insect bites, foods and many other substances so that an efficient immune system must include lymphocyte cells which can recognise every single antigen you are likely to meet in a lifetime. That is a tall order, and one that is becoming increasingly difficult. Even without these, an immune system capable of lasting a few decades needs about a million different lymphocyte receptors capable of recognising just about every antigen found in nature or created in a laboratory. If the immune system is not capable of 'recognising' an antigen, such as a new chemical or a partly digested protein that has found its way into the bloodstream, then the substance can become toxic, allergenic or even lethal to a living system.
It stands to reason that an incompetent immune system is likely to allow more foreign substances through to cause a reaction. The first epidemic in human history did not wipe out mankind, however, because the police, army, navy and air forces within us somehow manage to protect enough people for the human race to continue. During early biological catastrophes such as the Black Plague, there were no antibiotics or hospitals, yet many people survived. The only reason they did is that they possessed sufficient 'resistance' or, in other words, they were 'immuno-competent'.
The human body is eminently capable of defending and even healing itself. Immunologist Dr Ronald Glasser states:
To cure a disease, not just to treat it, you must help the body to do so itself. It is the body that is the hero, not science, not antibiotics nor machines nor new devices. It is the body making antibodies against the swallowed polio vaccine, not the iron lung, that cures polio. It is the body, not radiation or drugs, that must destroy cancer cells if the patient is to survive.
Louis Pasteur, the father of 'germ theory', once said that it was not bacteria but the 'soil' on which they fell that made all the difference between health and disease. What he meant, of course, was that although we are constantly inhaling, ingesting and touching germs of all kinds, relatively few of these organisms actually cause us any harm.
While our general immunity may be adequate, however, it may lack the capacity to respond to a particular invader. You may have poor resistance to viruses, for example. The results will be a series of colds, influenza and other infections and a general feeling of being tired and unwell all the time. As well, you may develop a strong, sometimes too strong, response to some factors that are not harmful in themselves, but to which your immune system over-reacts because you have been exposed to them for so long. In other words, your immunity may be overactive in some areas. This situation gives rise to allergic responses and auto-immune diseases.
A group of cancer cells, called tumours, can only grow if the immune system is incapable of destroying them. So our lives literally depend on the ability of our immune system to distinguish friends from foes. If you place a group of white cells called 'granulocytes' in a dish of saline solution and watch them through a microscope, you can see them swimming around peacefully. If you add just one bacterium to the solution, however, you will see the real-life 'Space Invaders' game taking place. The granulocytes will advance on the bacterium, much like cats stalking a bird, until they immobilise the enemy just long enough for another type of white cell, the macrophage, to literally eat the 'baddie'.
There are also antibodies which surround foreign structures in order to immobilise them so that they are easy targets for the granulocytes. The lymphocytes, made in the lymph nodes, are a group of white cells which constantly 'patrol' the body. They are so effective as a defence system that they will even attack bacteria for which we do not have antibodies.
There is growing evidence that many common drugs, including some antibiotics, tranquillisers, sulphur drugs and chemical additives, make excessive demands upon our immune systems,
with the result that we are becoming less and less able to resist the onslaught of life in general. Ironically, the very antibiotics which originally played such a central role in enabling humanity to overcome infections are probably now one of the main reasons for our increasing helplessness in the face of ever-diversifying viruses and bacteria.
The reason is quite simple. Most broad-spectrum antibiotics tend to kill friendly and useful bacteria along with the 'enemies'. Chemicals, toxins, pollutants, nutritional deficiencies or imbalances, allergies and even emotional stress combine to alter or reduce the efficiency of our immune defences. As a result we may become allergic or fall easy prey to more infections. We are then given more antibiotics which further affect our immuno-competence. Many micro-organisms are 'smart': they can develop resistance to one antibiotic after another. In the case of the Golden Staph, for example, we are now defenceless, and the new tuberculosis epidemic in the Western world is caused by past abuse of antibiotics. Another culprit is dental amalgam, which contains mercury. It has been found that mercury enhances the ability of some bacteria to resist modern drugs.