immunology exam review

purpose of the lymphatic system

purpose of the lymphatic system

protects and fights disease by collecting, cleaning and draining the fluid around the cells

purpose of lymph nodes

filters fluids of harmful particles before returning to the blood stream

function of tonsils

filters and destroys bacteria

function of thymus

produces hormones that help mature white blood cells

function of spleen

removes worn out red blood cells, platelets, bacteria and other particles from the blood; stores lymphocytes

function of histamines

trigger the inflammatory response. runny nose, sneezing, watery eyes, coughing

function of pyrogens

hormones which stimulate the brain to increase body temperature to disable the antigen

function of cytokines

Protein chemical messages produced by T cells to activate B cells and other cells of the immune system

function of interferons

A group of cytokins make and released by host cell in response to the presence of pathogens such as viruses, bacteria, parasites and tumor cells

function of interleukins

cytokins that are secreted by leukocytes to produce and immune response amogst other immune cells

function of complement

1. Expose reactive sites on antibody

2. Coats the antigen- antibody bond

3. Makes antigen more susceptible to phagocytosis

4. Ruptures foreign cells

5. Attracts macrophages and neutrophils

6. Alters structure of viruses

neutrophils

phagocytize small particles

basophils

releases heparins and histamines

eosinophils

kills parasites and helps control

inflammation and allergic reactions

monocytes

phagocytizes large particles

dendritic cells

process antigen material and preset it onthe cell surface to T cells found near the first line of defense

macrophages

eat large particles, bacteria, viruses and dead cells

waterborne infection

1. contaminated drinking water

2. prevalent in 3rd world countries

3. spreads disease very rapidly

airborne infection

1. spread by sneezing, coughing, talking

contact infection

1. can be spread by dirty glassware, silverware

2. puncture wounds

3. sexual contact

local infection

1. cuts, scrapes, puncture wounds

2. symptoms: redness, swelling (pus), pain, warmth

systemic infection

1. whole body

2. symptoms: fever, chills, aches

first line of defense

1. skin, scabs

2. mucus membranes in the nose, respiratory tract,

digestive tract and reproductive tract

3. Hair including cilia in the respiratory tract

4. Tears contain lysozyme, an antibacterial enzyme

5. Stomach acid

6. Symbiotic Organisms: E Coli living in the stomach provide Vit K and compete with harmful bacteria

second line of defense

1. White blood cells- Leukocytes

a. phagocytes – digest foreign particles and pathogens

b. macrophages- large phagocytes

2. Inflammatory response

3. Antimicrobrial proteins

cells involved in 3rd line of defense

B- Lymphocytes (B cells): made and matured in bone marrow, creating antibodies

phagocytes vs macrophages

phagocytes – digest foreign particles and pathogens

macrophages- large phagocytes

what is a lymphocyte?

b cells and t cells that are made and matured in bone marrow

t cells

have a direct interaction with antigens

b cells

protects the body from infection by creating antibodies

antibodies

immunoglobins, fights against antigens and infections

memory b cells

do not express antibodies but circulate in blood serum seeking out specfic pathogens

plasma b cells

produce antibodies (immunoglobins)

cytotoxic t cells

destroy virus infected cells and tumors

helper t cells

make cytokins which activate and coordinate other cells to participate in the immune response

t 4 cells

coordinate T cells and B cells; this is the cell that is attacked by HIV

non-specific defenses

innate immunity (lines of defense)

specific defenses

adaptive immunity (humoral response)

active immunity

Acquired by the making of antibodies by the body through illness or vaccines

passive immunity

Antibodies are produced from another source, like a mother’s milk or blood stream, or an injection (ex: tetanus shots used to come from horse blood)

live virus vaccine

pros: often given orally or as a nasal spray, can multiply in the body without harming it, has a public health benefit because it can be passed from person to person, quicker protection

cons: people with a weak immune system might get sick from the vaccine

killed virus vaccine

pros: safer because it cannot multiply in the body, made quicker

cons: vaccine has to be given in larger amounts which may cause an allergic reaction in some individuals

antibiotics

germ killing substances made from fungi, plants, animals or bacteria that slows down the production of bacteria, it cannot be used against viruses and is given after infection not before

vaccines

contain weak or killed antigens which cause the immune system to create antibodies against that antigen, it must be given before infection, it cannot cure an infection already present, mostly used against viruses

HIV

The virus responsible for AIDS, HIV replicates inside helper T-cells and T4 cells and attacks these cells and is spread by blood, semen, or breast milk contact

HIV symptoms

vary depending on level of HIV infection, flu like symptoms, fever, weight loss, swollen lymph nodes, night sweats, sore throat, rash, genital sores

AIDS

A condition in which the body’s immune system cannot protect itself against pathogens

polio

an infectious disease caused by a virus that can spread from person to person and cause paralysis, preventable by vaccine

polio symptoms

paralysis, fatigue, feeling faint, fever, or wasting away, muscle weakness, loss of muscle, or muscle quiver

IgM

1st to respond in a primary response to an antigen, found on B cell

IgA

most common antibody; protects portals of entry to the body, found in saliva, tears, breast milk and mucus, floating free in blood serum

IgE

responds in Allergic reactions; responds to parasite infections, floating free in blood serum

IgD

Found on Mature B cells

IgG

effective against antigens in a secondary response; found in the placenta protecting the fetus; effective against toxins, viruses and bacteria, floating free in blood serum