A & P 2 (Immune system)

How does the immune system respond to an invasion by a pathogen

Both the innate (nonspecific) and adaptive parts (specific) of the immune system respond

First line of defense

1. Intact skin epidermis (acid mantle of the skin, keratin)

2. intact mucous membranes (mucus, nasal hairs, cilia, gastric juice, acid mantle of vagina, lacrimal secretion (tears)

3. saliva

4. urine

Second line defense

1. Phagocytes (neutrophils and macrophages)

2. Natural killer cells

3. Inflammation (histamine, kinins, prostaglandins, complement, and cytokines)

4. Antimicrobial proteins

5. Interferons

6. Fever

What do each of these innate (nonspecific) internal defenses do in the body ( 1st & 2nd line defenses)

Complement activation causes cell lysis

main events during inflammation

1. Physical trauma

2. intense heat

3. redness

4. swelling

What are antigens

Substances that provoke an immune response, seen on the external surface of the external surface of cells, may be bacteria, viruses or cells from another individual

1. humoral immunity

2. cellular immunity

1. Humoral immunity involves B lymphocytes and includes antibody secretion.

2. Cellular immunity involves T lymphocytes and targets intracellular pathogens.

What are cytotoxic T lymphocytes and what do they do?

Attack mismatched recipient cells.  Rid the body of cancer cells and cells that are infected by viruses and take part in graft rejection, require MHC proteins to display the antigens on the cell surface, attack the target cell membrane and are stimulated by helper T cells

What are antibodies

Proteins produced in response to antigens.

How are antibodies made and what cells increase when antibodies are being produced

B lymphocytes produce plasma cells and plasma cells manufacture antibodies.

What is passive, natural immunity and what is an example

When your immune system fetus receiving antibodies directly from the mother

What is passive, artificial immunity and what is an example

When your immune system isn’t making antibodies but receiving them from an artificial shot (e.g. receiving a shot of antibodies before traveling to a foreign country)

What is active, natural acquired immunity and what is an example

When your immune system created antibodies in response to being exposed to an antigen naturally (e.g. being exposed to measles)

What is active, artificially acquired immunity and what is an example

When your immune system creates antibodies after receiving a vaccination or shot.  An example would be if you are receiving a vaccination of a weakened virus like the flu shot.  

• In this case, the flu virus challenges the immune system and the immune system manufactures antibodies that will mount a response against the antigens.

 

1. primary response to an antigen

2. secondary response to an antigen

1. The primary immune response occurs on the first exposure to a particular antigen and has a lag time of 3-6 days after the antigen encounter.

2. The secondary occurs when the antigen is reexposed to the same antigen and is more prolonged because there is immunological membrane and the immune system can respond much more quickly

mechanisms of action that occur during an antibody-antigen reaction

1. Neutralization

2. agglutination

3. precipitation

4. complement fixation

5. cell lysis

What are the names of the antibodies are what are their functions

1. IgM – first immunoglobulin class secreted by plasma cells during the primary response

2. IgA – found in body secretions such as saliva, sweat, intestinal juice and milk,

3. IgD – found on B cell surface and functions as a B cell antigen receptor

4. IgG – most abundant antibody in plasma accounting for 75%-85% of circulating antibodies

5. IgE – binds to mast cells or basophils, antigen binding to its receptor end triggers these cells to release histamine and other chemicals that mediate inflammation and an allergic reaction

What is the immune system response to AIDS

Helper T lymphocytes are destroyed

 

What is an autoimmune disease and what are some examples

This type of disease results from the inability of the immune system to distinguish self from non-self, examples are rheumatoid arthritis, multiple sclerosis, Graves’ disease, Type 1 diabetes mellitus, lupus, and glomerulonephritis

What events happen when there is a hypertensive reaction

Occurs when the immune system damages tissue as it fights off a perceived threat that would otherwise be harmless to the body, hypersensitive reactions cause IgE antibodies to be secreted that attach to the surface of the body’s mast cells and basophils; other reactions from the body include an allergic reaction with mast cells and basophils releasing histamine