CH 6 LYMPHATIC AND IMMUNE SYSTEM CENGAGE

What are the 3 main functions of the lymphatic system?

absorb fats and vitamins through the small intestines, remove waste products from tissues and destroy pathogens, and to return filtered lymph to the veins at the base of the neck

Lacteals

specialized structures that absorb fats that cannot be transported by the bloodstream. the dietary fats are transformed in the cells of the lacteals- then return them to the venous circulation so they can be used as nutrients

Villi

fingerlike projections in the small intestines- each one contains lacteals and blood vessels

Interstitial Fluid

plasma from arterial blood that flows out of the arterioles and into the capillaries, and then flows into the spaces between the cells of the tissues

Lymph

clear, watery fluid containing electrolytes and proteins- helps protect the body

Lymphatic Circulation

depends on the pumping motion of muscles and such to move- moves in one direction and is filtered by lymph nodes

Lymphatic Capillaries

microscopic, blind-end tubes located near the surface of the body, one cell thick

Lymphatic Vessels

flow from lymphatic capillaries into progressively larger lymphatic vessels, prevent the backward flow of lymph

Right Lymphatic Duct

collects lymph from the right side of the head and neck, the upper right quadrant of the body, and the right arm

Thoracic Duct

collects lymph from the left side of the head and neck, the upper left quadrant of the trunk, the left arm, the entire lower portion of the trunk, and both legs

Cervical Lymph Nodes

located along the sides of the neck

Axillary Lymph Nodes

located under the arms in the armpits

Inguinal Lymph Nodes

located in the groin area of the lower abdomen

Lymphocytes

Leukocytes, Natural Killer Cells, B Cells, T Cells, Cytokines, Interferons, Interleukins

Leukocytes

formed in bone marrow as stem cells- defend the body against antigens (foreign substances)

Natural Killer Cells (NK Cells)

play a role in killing cancer cells and cell infected by viruses

B Cells (B Lymphocytes)

specialized lymphocytes that produce antibodies, transform into plasma cells when confronted with an antigen, after transformation into plasma cells they destroy specific antigens

T Cells (T Lymphocytes)

get the "T" in their name from their origin in the Thymus, play central role in cell-mediated immunity

Cytokines

group of proteins such as interferons and interleukins that act as intracellular signals to begin the immune response

Interferons

activate the immune system, fight viruses, and signal other cells to increase defenses

Interleukins

play multiple roles in the immune system and direct B and T cells to divide and proliferate

The Tonsils

three masses of lymphoid tissue that form a protective ring around the back of the nose and upper throat

Adenoids (Nasopharyngeal tonsils)

located in the nasopharynx

Palatine Tonsils

located on the left and right sides of the throat in the area visible at the back of the mouth

Lingual Tonsils

located at the base of the tongue and not readily visible

Thymus Gland

located above the heart that becomes smaller with age, secretes a hormone that stimulates the maturation of lymphocytes into T cells- T cells leave the thymus through the bloodstream

Vermiform Appendix

referred to as the appendix-hangs from the lower portion of the cecum in the first section of the large intestine- research suggests it may play a part in the immune system

Spleen

Sac-like mass of lymphoid tissue located in the left upper quadrant of the abdomen- filters microorganisms from the blood, forms lymphocytes and monocytes, destroys worn-out erythrocytes, and stores extra erythrocytes

Pathogens

disease producing microorganisms

Allergens

substances that produce allergic responses

Toxins

poisonous or harmful substances

Malignant Cells

potentially life-threatening cancer cells

Immune System Response

first attempts to prevent entry, then uses chemical signaling to attack, then creates memory of the invader for more efficient defense

First Line of Defense for the Immune System

Intact Skin- physical barrier covered with acid mantle that makes inhospitable environment for most bacteria

Second Line of Defense for the Immune System

Respiratory System- traps inhaled foreign matter with nose hairs and mucous membrane, uses coughing and sneezing to expel foreign matter that gets past initial barriers

Third Line of Defense for the Immune System

Digestive System- acids and enzymes destroy invaders swallowed or consumed with food

Fourth Line of Defense for the Immune System

Lymphatic System- destroys pathogens that succeed in entering the body

Antigen-Antibody Reaction (immune reaction)

involves binding antigens to antibodies- this reaction labels a potentially dangerous antigen- immediately responds to the presence of any antigen

Antibodies

disease fighting proteins

Immunoglobulins

group of proteins that normally circulate in the blood in an inactive form- when needed, ward of pathogens by combining with them to dissolve and remove pathogenic bacteria and other foreign cells

Natural Immunity (passive immunity)

resistance to a disease present without the administration of an antigen or exposure to a disease

Acquired Immunity

obtained by having had a contagious disease

Vaccination

provides protection against the disease; however, for some conditions a periodic booster is required

Allerigst

specialist in diagnosing and treating conditions of altered immunologic reactivity, such as allergic reactions

Infectious Disease Specialist

specialist in diagnosing and treating diseases caused my microorganisms

Immunologist

specialist in diagnosing and treating disorders of the immune system

Lymphologist

specialist in diagnosing and treating disorders of the lymphatic system

Oncologist

specialist in diagnosing and treating malignant disorders, such as tumors and cancer

Lymphadenitis (swollen glands)

inflammation of the lymph nodes

Lymphadenopathy

any disease process affecting a lymph node or nodes

Lymphangioma

benign tumor formed by an abnormal collection of lymphatic vessels

Ruptured Spleen

torn covering of the spleen

Splenomegaly

abnormal enlargement of the speen

Lymphoscintigraphy

diagnostic test that detects damage or malformations of the lymphatic vessels by injecting a radioactive substance into the lymph ducts- scanner or probe is used to follow the movement of the substance on a computer screen

Lymphedema

swelling of the tissues due to an abnormal accumulation of lymph fluid within the tissues

Primary Lymphedema

hereditary condition that develops with swelling beginning in the feet and progressing into the ankles and in an upward direction along the legs

Secondary Lymphedema

caused by damage to the lymphatic vessels- most frequently due to cancer treatment, surgery, trauma, or burns

Bioimpedance Spectroscopy

noninvasive method of diagnosing lymphedema- measures the resistance to an electrical current passed through the affected limb, with abnormally low results showing a buildup of lymph

Allergy

overreaction to a particular antigen

Localized Allergic Response

(cellular response) includes redness, itching, and burning where the skin has come into contact with an allergen

Systemic Reaction

anaphylaxis or anaphylactic shock- severe response to an allergen

Scratch Test

identifies common allergens

Antihistimines

medications used to relieve or prevent allergy symptoms

Autoimmune Disorders

large group of diseases characterized by the immune system producing antibodies against its own tissues- appears to be genetically transmitted, women affected more than men

Immunodeficiency Disorders

occur when the immune response is compromised

Severe Combined Immunodeficiency

increased susceptibility to infection and failure to thrive as a result of infections

Human Immunodeficiency (HIV)

damages or kills the T cells of the immune system, causing it to progressively fail

Acquired Immunodeficiency Syndrome (AIDS)

advanced and fatal stage of HIV

Opportunistic Infection

caused by a pathogen that does not normally produce an illness in healthy humans

Kaposi's Sarcoma

opportunistic infection associated with HIV; cancer

ELISA (enzyme-linked immunosorbent assy)

used to screen for HIV

HIV Differentiation Assay

used to confirm positive ELISA test

Biological Therapy

involves either stimulating or repressing the immune response

Treatment of Cancers

Immunotherapy stimulates the immune response to fight the malignancy

Treatment of Allergies

Immunotherapy represses the body's sensitivity to a particular allergen- treatment known as allergy desensitization or allergen immunotherapy

Synthetic Immunoglobulins

used as a post-exposure preventative measure against certain viruses

Synthetic Interferon

used in the treatment of multiple sclerosis, hep C, and some cancers

Monoclonal Antibodies

antibodies produces in the lab by identical offspring of a clone of specific cells, used to enhance a patient's immune response to certain malignancies, including non-Hodgkin's lymphoma, melanoma, breast cancer, and colon cancer

Antiretroviral Therapy (ART)

sometimes referred to as a treatment regimen- often more than one drug must be taken in combo with each other (HIV treatment)

Pre-Exposure Prophylaxis

daily preventative HIV drug for people at high risk

Post-Exposure Prophlylaxis

for people with suspected or confirmed HIV exposure

Immunosuppression

represses or interferes with the ability of the immune system to response to stimulation by antigens

Immunosuppressant

prevents or reduces the body's normal immune response, administered to prevent rejection of donor tissue and to depress autoimmune disorders

Corticosteroid Drug

synthetic hormone that closely resembles the cortisol secreted by the adrenal glands

Cytotoxic Drug

medication that kills or damages cells, used as immunosuppressants or as antineoplastics

Pathogen

microorganism that causes disease in humans

Bacteria

one-celled microscopic organism- most are harmful to humans

Examples of Pathogenic Bacteria

Bacilli, Anthrax, Rickettsia, Shingella, Streptococci

Antibiotic-Resistant Bacteria

occur when antibiotics fail to kill all off the bacteria they target- surviving bacteria become resistant to this drug

Methicillin-Resistant Staphylococcus Aureus

resistant to most antibiotics, difficult to treat and cal be fatal, often occur repeatedly as breaks in the skin allow bacteria entry

Fungus

simple parasitic organism

Tinea Pedis

Athlete's foot- fungal infection

Aspergillois

rare infection caused by mold (fungus) inhaled into the lungs

Yeast

type of fungus

Candidiasis

yeast infection on the skin or mucous membranes in warm, moist areas

Candida Albicans

oral thrush- yeast infection that occurs in the mouth

Vaginal Candidiasis

yeast infection that occurs in the vagina

Giardiasis

diarrheal disease caused by the parasite Giardia- most common method of transmission is water that has been contaminated with feces

Malaria

caused by a parasite that lives in certain mosquitoes- transferred to humans by the bite of infected mosquito

Toxoplasmosis

caused by a parasite; most commonly transmitted by contaminated feces