Most of you are familiar with allergy problems; however, very few understand the term “Immunology.” The immune system protects us from the outside environment so we can all lead a healthy life. The immune system consists of many different types of cells, and these cells make antibodies and mediators. The combination of these mediators and antibodies work to keep us healthy. If they do not function, people develop a group of diseases called immunodeficiency diseases. A common example that we all know now is AIDS, which is caused by the HIV virus that attacks the immune cells.
Allergic Diseases as a group develop when part of the immune system reacts excessively and produces an immunoglobulin called IgE antibody. This IgE antibody system is supposed to fight the parasitic infections; however, it reacts to the normal environmental antigens (dust mite, animal dander, pollen, mold spores, insect venom, and food). These diseases include asthma, allergic rhinitis, conjunctivitis, eczema, insect sting allergy, and some forms of hives.
If the immune system reacts to self antigens, people develop a group of diseases called auto-immune diseases. For the immune cells to react they have to recognize which is self and non-self. In most of us, immune cells can perform this function very effectively; however, in some patients who have a genetic tendency they recognize the self antigens as foreign and react to them. There is a constant reaction which goes on between the self antigens and antibodies which create inflammation. Some examples of these diseases are lupus, rheumatoid arthritis, polymyositis, etc…
Immune cells also do surveillance in the body and if they recognize any foreign cell or a tumor cell they will kill these cells. People who do not have enough of these cells are more prone to malignant diseases or cancers. As you can see, the immune system is the key to keeping us healthy. Most of these diseases do have a genetic tendency; however, environmental factors lead to the diseases. Most of the people who have asthma have a genetic tendency; however, they must be exposed to an allergen or a virus to develop an asthma attack.
Even though as allergists and immunologists we do not deal with all these diseases, we have a clear knowledge of how the immune system works and how to diagnose these diseases.