The Immune System!

Group 1 Non-Specific Defenses (innate immunity) Your skin acts as a protective barrier; sweat, dead cells and oil help your skin block out any/all invaders. Hairs in your nose, ears and eyes help to keep any/all invaders out. Ear wax, tears and mucus in your nose trap any/all invaders. Stomach acids and enzymes destroy any invaders that get that far. Lysozyme, an enzyme found in tears and saliva, help to destroy invaders.

Group 2 Non-specific Inflammatory Response This response is for anything that gets through the first line of defense such as skin, mucus and etc.  Damaged cells may release interferons that slow the functioning/replication of viruses  Damaged cells may release another chemical that leads to:  Increased blood flow = swelling, redness and warmth  Increased blood flow = more white blood cells called PHAGOCYTES. These gobble up invaders or invaded/damaged cells.  Fever increases the body’s temperature which:  Increases the functioning of the WBC  Decreases the functioning of invaders

Group 3 Humoral Immunity (antibodies!) Pathogens (disease causers) have protein markers on their exterior that identify them as invaders  These markers are called antigens. B-lymphocytes (B-cells) are specialized white blood cells. These will produce specific antibodies to fight the invader. Antibodies will bind with the antigen on the exterior of the invader. This causes the invaders to clump up, or agglutinate. T-lymphocytes are WBC that mature in the thymus gland. They activate and supervise antibody production.

Group 4 Immunity!! A vaccination is a weakened or dead form of a pathogen that can trigger the production of antibodies. Now, if you are exposed a second time, your B-cells will quickly make the right antibodies and you won’t get sick. Primary Immune Response – occurs the first time you are exposed to a pathogen. Secondary Immune Response – occurs the second time you are exposed…..is a much swifter response….you probably won’t even know you were exposed! Active Immunity – When you make your own antibodies after exposure or a vaccination. Passive immunity – when you are given antibodies such as through a vaccine or breastfeeding. Breastfeeding – the best way to give antibodies to a newborn.

Group 5 T Cells!!! Helper T-cell – ID’s foreigners and gets the immune system responding to an infection. Killer T-cell – destroys cells that have been invaded by a pathogen; destroys cancerous cells. Suppressor T-cell – calms down B-cells and other T- cells once infection has been dealt with. Transplant rejection – When Killer T-cells destroy the cells of a transplanted organ. Can be controlled with immunosuppression drugs. Patient is now susceptible to any infection.

Group 6 Allergies and autoimmune diseases Mast cells – a type of immune cell found mostly in the nasal passages; mast cells react with foreign particles. Histamine – produced and released by mast cells in response to foreign particles; histamines increase the flow of blood flow and fluids to the area…resulting in sneezing, runny nose, watering eyes, etc. Asthma – the most serious allergic reaction resulting in constriction of the air passages. Antihistamines – reduce the impact of histamines. Autoimmune disease – when your immune system can no distinguish between “self” and “non-self” and attacks the body’s own cells. Examples are type 1 diabetes, lupus and multiple sclerosis.

Group 7 HIV HIV is a retrovirus ….this means that it has RNA instead of DNA. Retroviruses must convert their RNA to DNA before they can infect a host cell. Because of this, retroviruses have a higher mutation rate. HIV targets and destroys the Helper T cell. Without the Helper T, many foreigners are not identified and dealt with. HIV antibodies are present in the blood once infection has occurred.