The Immune System The Immune system has a series of canals that collect body fluid that has left the blood vessels. It then collects it like fluid in storm drains and checks this “lymph” for bad guys at the lymph nodes before returning the fluid to the blood vessels & back into circulation.

THE BODY’S DEFENSE Within your body there is a group of warrior cells waiting to protect and defend against all evil..... The Warrior Cells/White Blood Cells

Pathogens & Antigens: Some are harmful, some are not! Pathogen! Antigens “Pollen” “Dust” “Peanuts”

The Evil Invaders: Pathogens… Antigens??? Pathogens = Anything that can cause disease. Examples: Bacteria, Virus, Fungi, Proteins. Antigens = Anything that causes an immune reaction (even if it is not harmful). Examples: Pathogens, parts of pathogens, Toxins, Venom, Pollen, “pet dander”, nuts, vegetables, dust…

Pathogens & Antigens: Some are harmful, some are not! Pathogen! Antigens “Pollen” “Dust” “Peanuts”

The Pathogen: He’s on a mission to multiply!!!

Non-Specific Defenses Non-specific defenses: Skin Mucous membranes Inflammation (histamine) Fever Macrophages (First line defense) Fences & Barbwire (Second line defense) Land Mines & Carpet Bombing

Non-Specific alerts Specific… MACROPHAGE: “Big Eater” The macrophage will “eat” any invader. If needed, will call for T cells and B cells (the warriors) to attack!!!

NON-SPECIFIC Alerts SPECIFIC Macrophage B-CellT-Cell BAD GUY Pathogen …Two Cells out of millions “asleep” in the Lymph Nodes… Will you find them in time???

Specific Defenses Specific Defenses: Macrophages* Call For: T-Cells (helper & killer) B-Cells

The Killer T-CELL

T-Cell directly attacking the pathogen The T-Cell destroys the pathogen by spewing enzymes on it… It’s Chemical Warfare!

Killer T-Cells = directly ATTACK Once activated, Killer T-cells will search out and directly destroy the pathogen or infected cells where the pathogen is hiding.

The B-Cell Designs antibodies to disable only the specific pathogen that is designed for. Y Y Y Y Y Y Y Y Y YY YYY Y

B-Cells – make anti-Bodies B-Cells = Produce and release specific antibodies that disable the antigen. Antibodies = Y shaped “handcuffs” that only disable the antigen they were designed for.

Helper T-Cells: Mediator

The Helper T-Cell will: 1. Stop the attack of the Killer T-cell if too aggressive. 2. Signal for more B-cell production.

Special Circumstances Cancer – is you, which makes it hard to stop, but killer T cells also can destroy cancer cells. Allergies – immune response to harmless antigens. Autoimmunity – immune response to body’s normal good cells Immune deficiency – inability to launch a good immune response Vaccinations – teach B-cells how to make antibodies for various pathogens.

Defending against… Bacteria Are cells and can live and multiply on their own inside your body. “Antibiotics” work against living things “Vaccination” prepares your body for attack with memory cells & Antibodies Viruses Are not cells and only “live” when they take over YOUR CELLS. “Antibiotics” don’t work against viruses!!! “Vaccination” makes Antibodies which will work fighting against Bacteria and Virus

Review CELL TYPEANALOGYFUNCTION Pathogen (Underwood) Bad GuyContains antigen that immune system recognizes as dangerous. Macrophage (The Big Eater) Patrolman – (The thin blue line) Identifies the Bad Guy. Calls for the Specific immune Response. B-cell (Eckman) CIA agent – controls drones Matures into Plasma Cells that make antibodies that destroy or disable the bad guys for elimination Killer T-cell (Morrison) AssassinAggressively Kills pathogens/infected cells. Helper T-cells (Jimenez) “Arc-Angel”Mediates Immune Responses using hormones. 1. Describe difference between Non-specific and specific defenses. 2. Compare the two types of specific defenses (T vs. B lymphocytes). 3. What is important about the situations below: Allergies Vaccinations Autoimmunity Immune deficiency Cancer