By the end of this presentation, you will know: The cells involved in the innate immune system Chemicals involved in the innate immune system How the inflammation response happens How fever happens

Physical barriers are your first line of innate defense Cilia on bronchial cells Hair, skin, cilia, and mucus keep potentially harmful invaders out in several ways.

Your second line of innate defense involves types of white blood cells and other special cells White blood cells, often called leukocytes, are made in your bone marrow. Not all leukocytes mature in the same way. Some migrate to the thymus as part of their maturation process. White blood cells What type of bone marrow produces blood cells?

Leukocytes can tell what should be in your body and what shouldn’t Leukocytes identify what should be in your body by recognizing antigens. Your immune cells give an okay to antigens you were born with but not to ones that are new. What happens when a person receives blood that contains an antigen his or her body doesn’t recognize?

Leukocytes are all around your body, and they have an ability to move Leukocytes, like this macrophage, can travel to any part of your body. They have a few tricks: some can change shape and size, and others can replicate themselves quickly. A macrophage engulfing an old red blood cell

There are three types of phagocytes Name of cell Characteristics Neutrophil Eosinophil Macrophage

There are three types of phagocytes Name of cell Characteristics Neutrophil Most plentiful white blood cell, very mobile, quick to attack invaders. Roams through the circulatory system, ready to enter tissues where and when it’s needed. Lives for a few hours to a few days. Eosinophil Engulfs pathogens or compounds that have been identified by other cells. Lives about 8‒12 days. Macrophage Long-lived, large cells. Some stay in specific tissues, whereas others can migrate to a site where they’re needed. Lives months to years.

Natural killer (NK) cells attack cancer cells and cells infected by viruses NK cells kill their target cells by secreting chemicals that cause the target cell’s membrane to disintegrate.

Proteins in blood plasma, called complement, bind to the membranes of foreign cells When complement binds to foreign cell membranes, the complement proteins become activated. They make tiny holes in the foreign cell membrane, killing the cell. What do you imagine would cross the cell membrane if there are holes in it?

Interferons are proteins that “interfere” with the activity of viruses Cells infected with a virus can secrete interferons, which tells neighboring cells to take defensive steps against a viral attack. Molecule of interferon

Name two important characteristics of neutrophils. Do Now Name two important characteristics of neutrophils. What do interferons do? What are two ways neutrophils and macrophages different?

What do you guess antihistamines do? When you’re injured, damaged cells release chemicals called histamines and kinins The inflammatory chemicals histamines and kinins are the security system’s warning that there’s been a break-in. They start off a set of responses that result in inflammation. What do you guess antihistamines do?

Histamines and kinins cause blood vessels near the injury to dilate Histamines and kinins also make capillary walls leaky so that neutrophils can easily leave the blood and go where they are needed.

What incidents have caused inflammation for you? Inflammation is the body at work protecting and repairing the site of an injury Inflammation is characterized by four signs: • Redness • Heat • Swelling • Pain What incidents have caused inflammation for you?

A fever is your whole body responding to infection When white blood cells meet certain pathogens, they secrete chemicals called pyrogens. Pyrogens reset your body’s thermostat so that you heat up. If you have a fever of 104, do you treat it differently from a fever of 100? Why?

Body’s Lines of defense Types of Immunity Innate Immune Vocab Adaptive Immune Vocab

Pictures and Mnemonics Pictures and Mnemonics Words and Definitions

By the end of this presentation, you will know: How immunity is defined How B cells and T cells confer immunity What antibodies are How vaccines work

What are some specific examples of invaders? Your acquired defenses recognize specific invaders that made it past your innate defenses Cells that carry out the acquired immune responses react to the presence of specific antigens brought into the body by a particular organism or substance. What are some specific examples of invaders?

There are thousands of nonself antigens Antigens can be part of something alive, like a bacterium, or inanimate, like pollen. Your body can recognize far more antigens than you will ever be exposed to. Pollen grains

What are some bones that contain red marrow? Cells that can recognize specific antigens are called lymphocytes Lymphocytes are made in bone marrow. B cells are so named because they begin maturing while still in the bone. T cells migrate to the thymus to begin their maturation. What are some bones that contain red marrow?

Many mature lymphocytes circulate in your blood After a lymphocyte has met its antigen match, it completes its maturation. The mature cell remains on guard for years, ready to take on the same agent if it appears again. Lymphocyte

The two cell types go through two types of immune response B cells Antibodies T cells Other types of T cells B cells release antibodies that circulate in your body fluids. This is called a humoral response (body fluids used to be called humors). T cells produce many other types of cells that take on different roles. This is called a cellular response.

Humoral response begins when B cells encounter their antigen match The B cells then quickly make an army of clones. Most of these clones become plasma cells.

These plasma B cells produce antibodies Antibodies are proteins that bind with antigens. The plasma cells produce billions of copies of the same antibody. Like T and B cells, antibodies have specific antigen matches.

When antibodies bind with antigens, they deactivate them Antibodies may bind in places that block the ability of a cell or virus to harm your body’s cells. Or they may make invaders clump together. Phagocytes clean up the deactivated antigens.

The B cell clones that don’t become plasma cells become memory cells Memory cells kick the system back into high gear when they meet the same antigen again. This ability to recognize and fend off invaders as a result of having met them before is called immunity.

Cellular immunity involves T cells and requires antigen-presenting cells Like B cells, T cells become fully active only when they meet their antigen match. T cells can’t bind with antigens on their own. They need the antigens presented to them by antigen-presenting cells, or APCs.

APCs notify T cells of antigens The APCs engulf substances or organisms that have antigens and move bits of the antigen to their cell membranes. Then they present the antigen bits, like memos with instructions, to the appropriate T cells.

Once activated, the T cell, like the B cell, makes many clones of itself Unlike B cells, T cells make many different types of clones, with different roles. Helper T cells send out the call to many other types of immune cells.

How do cytotoxic T cells differ from natural killer cells? Cytotoxic T cells, also called killer T cells, attack cancerous cells and cells infected with a virus Some cytotoxic T cells become memory T cells, conferring immunity in the same way memory B cells do. How do cytotoxic T cells differ from natural killer cells?

Body’s Lines of defense Types of Immunity Innate Immune Vocab Adaptive Immune Vocab

Pictures and Mnemonics Pictures and Mnemonics Words and Definitions