Monica Estella and Maria Reyes

Major Functions Provides protection from bacterial, parasitic, fungal and

viral infection and from the growth of tumor cells. Cells have specialized functions; they can engulf bacteria,

kill parasites or tumor cells, or kill viral-infected cells. http://videos.howstuffworks.com/hsw/6074-disease-defense-the-immune-system-

video.htm

Organs Thymus: immature thymocyte cells also known as prothymocytes leave

the bone marrow and migrate into the thymus; which then produces mature T- Cells.

Spleen: it’s made up of B cells, T cells, macrophages, dendrite cells natural killer cells and red blood cells; it cleans the blood and macrophages and dendrite cells bring antigens to T and B cells , which triggers an immune response. Red blood cells are destroyed.

Lymph Nodes: Composed of T cells, dendritic cells and macrophages. It filters the lymph, and macrophages and dendritic cells bring antigens to T and B cells, triggering an immune response.

Tonsils: site where lymphocytes are introduced to antigens(chemical markers) from pathogens.

Bone Marrow: All the cells of the immune system are derived from stem cells in the bone marrow. The bone marrow is the site of origin of red blood cells, white cells (including lymphocytes and macrophages) and platelets.

Cells White Blood Cells:five types:

-Neutrophils(NE):have sacs (granules) containing enzymes that digest bacteria and other microorganisms; process is

called phagocytosis.

- Monocytes(MO): made in the bone marrow; macrophages and dendrite cells.

- Eosinophils(EO): secrete substances which turn off chemicals that mediate infections, and can destroy cancer cells.

- Basophiles(BA): release histamine and other chemicals that help dilate the blood vessels when an immune response is

triggered - Lymphocytes(LY): T cells, B cells, and NK cells T-Cells: responsible for cellular immunity; our defense against abnormal cells and pathogens inside cells.

- two kinds: T helper: stimulates the activation and function of both T and B cells.

Cells (cont.)- Cytotoxin T-cell: attack foreign cells or body cells

infected by viruses.

Both T cells depend on the lymph nodes and the spleen to get the message to initiate an immune response.

B-Cells: produce antibodies in response to foreign bacteria, viruses, and tumor cells; responsible for humoral immunity, defense against antigens and pathogens in body fluids.

*antibodies attach to antigens, signaling other cells to engulf, kill or remove from the body.

Natural Killing Cells(NK): kill all cells without prior warning. Macrophages: white blood cells that engulf the antigens

http://www.educationalvideos.com/the-components-of-an-immune-system

ImmunityHumans have three types of

immunity: Innate: everyone is born with, it does not require the body to

identify the potential pathogen before it acts. it protects from germs

that affect animals. It includes physical barriers like the skin, as

well as secretions like tears or mucous. Adaptive: active immunity; develops throughout our lives .

Involves lymphocytes and develops as exposure to disease or vaccination occurs.

Passive: is “borrowed” from somewhere else and is temporary.

Immune Response

When an antigen triggers an immune response, it usually activates both T and B cells. The activation of T cell( usually happens first), involves active phagocytes exposed to the antigen. Once activated, T cells attack the antigen and stimulate the activation of B cells. Activated B cells mature into cells that produce antibodies; antibodies in the bloodstream bind to and attack the antigen.

http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter24/animation__the_immune_response.html

InflammationInflammation

Disorders

Four main categories: Immunodeficiency disorders ( primary or

acquired). Autoimmune disorders(the body attacks

itself as foreign). Allergic disorders (overreaction to an

antigen). Cancers of the immune system.

Immunodeficiency Disorders

*when a part of the immune system is not working properly or not present.

Primary: when a person is born with an immunodeficiency.

Examples:— IgA Deficiency: when not enough

immunoglobulin(present in the saliva and other body fluids that help guard the entrances to the body) is produced. People tend to have allergies or get more colds and other respiratory infections; condition is not severe.

— Severe Combined Immunodeficiency(SCID): A.K.A. “ Bubbly boy disease”. Serious immune system disorder that occurs because of a lack of both B and T lymphocytes, which makes it almost impossible to fight infections.

Immunodeficiency Disorders

Acquired (secondary): develops after someone has a disease, but can also be a result of malnutrition, burns, or other medical problems; some medications can also cause problems with the proper functioning of the immune system.

Examples:

-HIV (human immunodeficiency virus) infection/AIDS (acquired immunodeficiency syndrome): slowly and steadily destroys the immune system. It’s caused by HIV; virus that wipes out certain types of lymphocytes called T-helper cells.

Immunosuppressants can reduce the immune system’s ability to fight infections; chemotherapy attacks cancer cells and fast-growing healthy cells as well.

Autoimmune Autoimmune DisordersDisorders

The immune system mistakenly attacks the body's healthy organs and tissues as though they were foreign invaders.

Example:-- Lupus: a chronic disease marked by muscle and joint pain and inflammation (the abnormal immune response also may involve attacks on the kidneys and other organs)

Allergic disordersAllergic disorders

The immune system overreacts to exposure to antigens in the environment. The substances that provoke such attacks are called allergens. The immune response can cause symptoms such as swelling, watery eyes, and sneezing, and even a life-threatening reaction called anaphylaxis. Medications called antihistamines can relieve most symptoms.

Examples:~ Asthma: respiratory disorder that can cause breathing problems. Lungs are oversensitive to allergens like pollen, mold, animal dander etc. The lungs can trigger breathing tubes in the lungs to become narrowed, leading to reduced airflow and making it hard to breath.

Cancers

† Occur when cells grow out of control.+ Lymphoma involves the lymphoid

tissues and is one of the more common childhood cancers.

+ Leukemia, which involves abnormal overgrowth of leukocytes, is the most common childhood cancer.

Interaction With Other Systems

System: Integumentary

Skeletal Muscular Nervous Endocrine

System

Immune

Provide physical barriers to pathogen entry; Langerhans cells in epidermis

and macrophages in dermis resist

infection and present antigens to trigger immune response; mast cells trigger

inflammation .

Lymphocytes and other cells involved in

immune response are produced and stores in bone

marrow.

Protects superficial

lymph nodes in the abdominal

cavity.

Microglia present antigens that

stimulate specific defenses; innervation stimulates antigen-

presenting cells.

Glucocorticoids have anti-inflammatory

effects; thymic hormones stimulate development and

maturation of lymphocytes; many

hormones affect immune function.

Immune

System

Provides IgA for secretion

onto integumentary

surfaces.

Assists in repair of bone

after injury; macrophages

fuse to become

osteoclasts

Assists in repair after

injury.

Cytokines affect

hypothalamic production of

CRH and TRH.

Thymus secretes thymic

hormones; cytokines

affect cells throughout

body.

Systems:

Cardiovascular

Respiratory

Digestive

Urinary Reproductive

System

Immune

Distributes WBCs; carries antibodies that attack pathogens; clotting response helps restrict spread of pathogens; granulocytes and lymphocytes produced in bone marrow

Alveolar phagocytes present antigens and trigger specific defenses

Provides nonspecific defense against pathogens

Eliminates metabolic wastes generated by cellular activity; acid pH of urine provides nonspecific defense against UTIs

Lysozymes and bactericidal chemicals in secretions provides nonspecific defense against reproductive tract infections

Immune

System

Fights infections of cardiovascular organs

Tonsils protect against infection at entrance to respiratory tract

Tonsils defend against infection and toxins absorbed from tract

Provides IgA for secretion by epithelial glands

Fun Facts Dieting decreases the NK functionality, thereby weakening the immune system. While the body needs some sunlight to produce vitamin D, too much sunshine can

suppress the immune system. Even after just one month of quitting smoking, smokers can strengthen the immune System The pupil of the eye expands as much as 45 percent when a person looks at something

pleasing. Laughing lowers levels of stress hormones and strengthens the immune system. Six-year-

olds laugh an average of 300 times a day. Adults only laugh 15 to 100 times a day. Every time you sneeze some of your brain cells die. When you blush, the lining of your stomach also turns red. If you are right handed, you will tend to chew your food on your right side and vise versa. When hippos are upset, their sweat turns red. The only part of the body that has no blood supply is the cornea in the eye. It takes in

oxygen directly from the air. Intelligent people have more zinc and copper in their hair. Women blink nearly twice as much as men.