The branch of biology that studies immune systems in any organism is called immunology. Immunology is a relatively recent study, going back to 430 BCE but really making a surge in the late 19^th century. Studying the immune system allows for a deeper understanding to how organisms fight off infectious diseases, bacteria, or viral infections.

The earliest recorded immunology comes from the ancient city of Athens. In 430 BCE, a plague would infect many people, and it was Thucydides who would note that people who had already suffered and lived from the disease could not be infected again. There would be attempts later, but it wasn't until Ilya Ilyich Mechnikov, a Russian biologist, came along in the late 19^th century would it progress any further.

Mechnikov advanced immunology at a very rapid pace. He would receive a Nobel Prize in 1908 for his work. Some of his work included the observation of rapid cell regeneration in a starfish after being jabbed with the thorn of a rose. He noted that the body was actively responding to the thorn tip, and this allowed the starfish to maintain activity. Mechnikov would go on to be the first person to observe phagocytosis (the body fighting against a foreign body).

The study of diseases that are caused from disorders in the immune system is called clinical immunology. This can also include diseases in other systems where the immune system plays a part. There are two sections that the diseases are put into, immunodeficiency, parts of an immune system failing to operate normally, and autoimmunity, when the immune system lashes out at the person's body.

Immunology is mostly studied from birth to examine how the immune system develops. This is called developmental immunology, and centers around maternal factors, a person's age and their antigen's (whatever can create antibodies for the immune system to fight) type & location.

Once a child is born, their immune system responds to the various protein antigens positively, while rejecting other types of proteins. Infants don't have well developed immune systems yet, so learning how their immune system develops is important to preserving human life.

The immune system is completely inherited from the mother and her own immune system plays a large role. Not all immunity components are given through just birth, however, as portions of it must come from other sources, like breast milk. Antibodies are acquired through this, and can protect newborns for up to 18 months.

Once a child hits adolescence, their body goes through many changes caused by hormones. The hormone that affects females is known as estrogen and the hormone that affects males is known as testosterone. These steroids heavily influence the immune system, and can cause autoimmunity in some cases.

There are many ways to study immunology, and all the tools of biology are used to do so. With deeper understanding of our immune system, scientists can fight against diseases and infections better and faster than ever before. Further research continues, and if diseases, viruses, and harmful bacteria continue to evolve, there will always be a need for immunology.

Related Links: Science Biology Branches of Biology