1. Understanding Specific Immune 1800’s scientists determined – Antigen specific- acts against particular pathogens/foreign substances – Systemic- full body not just sight of initial infection – Memory- amounts a stronger attack upon 2 nd exposure

2. Specific defense system – Humoral-makes the antibodies (memory) – Cellular immunity- lymphocytes (white blood cells) defend directly with lysing or indirect with chemicals – a. A.K.A. “immune system”

3. Types of Immunity 1. Antibody-mediated immunity (HUMMORAL) – a. Cells (lymphocytes) produce chemicals (anti- bodies) to mark antigens for disposal. 2. Cell-mediated immunity – a. Cells target virus infected cells directly

4. Antigens (Nonself) 1. Any substance capable of activating the immune system and provoking an immune response 2. Examples of common antigens – a. Foreign proteins – b. Pollen grains – c. Microorganisms

5. Self-Antigens 1. Our cells have many surface proteins thus our system can recognize itself 2. Our immune cells typically do not attack our own cells (If it did that would be a homeostatic imbalance!) 3. BUT each persons surface proteins are unique so, our cells in another person’s body can trigger an immune response because they are foreign – a. Restricts donors for transplants – b. Can cause miscarriage

6. Cells of the Immune System 1. Lymphocytes – a. from stem cells in the red bone marrow – b. B lymphocytes create antibodies & memory cells (hummoral) – c. T lymphocytes specialized in the thymus gland (cell Mediated) 2. Macrophages (cell mediated) – a. Large cells that eat other invader cells – b. Become widely distributed in lymphoid organs

7. Immunocompetance All of your immune cells need to mature before they can do their job. Being immunocompetant means that the immune cell is able to bind to its specific antigen. B cells in bone marrow T cells in thymus 1 receptor for 1 antigen so each immune cell is immunocompetent is for 1 specific antigen!

8. Self-Tolerance The immune system need to be trained to go after antigens and avoid “self” cells. T cells go through this in the thymus. The T cells with the best ability to identify antigens survive. T cells that strongly identify with SELF antigens are destroyed! B cells go through this in the bone marrow but little is known about that… Autoimmune diseases are an issue with this process

10. Your GENES determine what specific foreign substances our immune system will be able to recognize and resist. Ebola is “new” to our immune system so it does not have a receptor for it in our bodies.

11. antigen-presenting cells Engulf antigens and present fragments of them on the outside of their cell. So they can activate T cells. A big part of activating the immune system – Dendritic cells – Macrophages- stay in the lymph nodes – B lymphocytes