These are environmental molecules which cause release of histamine from the bodies mast cells, leading to local inflamation. Imunoglobulins are also called antibodies.
Antibodies are how the immune system reacts to substances that affect it adversely.
Antibodies are also made against bacteria, viruses and fungus. An allergy is any adverse reaction to an environmental substance that most people find harmless. It may be a food or other environmental agent such as animal dander, dusts, pollens clothing or other substances. Allergies usually have a quick onset of symptoms. The reaction occurs almost immediately, usually within an hour and is often severe.