General Product Information

IMMUNOLOGY

Immunology is the study of the human defense wall - the immune system.

The immune system comprises a collection of cells, chemicals, and processes that help in protecting the skin, intestinal tract, respiratory passages from antigens like microbes, viruses, and other toxins. The human immune system is made up of two lines of defense: Innate immunity and Adaptive (Acquired) immunity.

INNATE IMMUNITY: It is the first wall of defense against any intruding pathogen. It is also called a "non-specific" immune system as it uses an antigen-independent defense mechanism. It does not have the ability to memorize or recognize the pathogen attack. Therefore, it does not have any immunologic memory should the body be exposed to it in the future.

The innate immune system consists of:

• The protection offered by the skin and mucous membranes
• The protection offered by the immune system cells (defense cells) and proteins

Adaptive Immunity: When innate immunity cannot tackle the pathogen, adaptive immunity triggers a more antigen-specific response. As it is a more antigen-dependent response, there is a lag time between the exposure and the response. It has the advantage to memorize the germs, so on exposure to the same pathogen again, the body can fight. This memory enables the body to be immune from a particular illness.

The adaptive immune system is made up of:

• T lymphocytes in the tissue between the body's cells
• B lymphocytes also found in the tissue between the body's cells
• Antibodies in the blood and other bodily fluids

Innate and adaptive immunity are not mutually exclusive mechanisms of host defense, but rather are complementary, with defects in either system resulting in host vulnerability or inappropriate responses.

Applications

• Transfusion and transplantation
• Learning to exploit antibodies
• Vaccination
• Immunotherapy