VI. Immune System Flashcards
immunosupressed
ie person on chemotherapueutic agents or high doses of steroids - cancer treatment or organ transplant
Immunocompromised
chronic diseases affecting major body system
Immunodeficient
HIV or AIDS
Susceptibility
NOT age related; breach of body’s immune system due to a co-existing condition wwith which the body is struggling to cope - chronic diseases
hypertension, diabetes, cancer, TB, AIDS
Vulnerability
Age specific, very young or elderly
Lack of resistance
body’s inability to defend itself against non-self
Immunity (adaptive or specific resistance)
Ability of body to differentiate SELF and NON-SELF
Nonspecific Defenses
1 Physical barriers
- Phagocytes
- Natural Killer Cells
- Interferons
- Complement
- Fever
- Inflammation
Physical Barriers (list)
Epithelial Coverings
Skin
Mucus membranes
Secretions
Hair, nailsPhagocytes (list)
Microphages (neutrophils, eosinophils)
Macrophages - most tissues, kill invading pathogens
Macrophage (definition, function)
Monocyte that leaves blood - migrate to connective tissue
OR - fixed macropahges - phagocytize pathogens that come to them
Chemotoxis
attracted or replled by chemicals (macrophages)
Diapedesis
squeeze between capillary cells (macrophages)
Types of fixed macrophages
Microglica (central nervous system)
Alveolar - lungs
Hepatic - Liver
Natural Killer Cells (NK Cells) - function
Recognize, destroy abnormal cells
What releases perforins?
Natural killer cells
What do perforins do?
Poke holes in cell membrane, allow water and salt in
What releases granzymes, what do they do?
NK cells; break down cells enzymes
Interferons (released by, function)
Small proteins released by:
lymphocytes
macrophages
virus-infected cells
INTEREFERE with replication of virus
Complement Activation
- destruction of invader
- inflammation
- attract phagocytes
- binding cites coat antigens
- bind
- circulate to liver and spleen for macrophages to remove
Activation pathway (2 ways)
Classic - rapid, antibody-antigen complex
alternate - slower, antigen triggered
Fever (function)
inhibits reproduction of bacteria and viruses, speeds metabolism and tissue repair
Causes of fever
Pyrogens 9 chemicals that reset hypothalmic thermostat
Pyrogens
Cause fever
Inflammation (produces)
swelling heat redness pain loss of function
Hyperemia
increased blood flow, causes vasodilation
Heparin
prevents clotting at site of injury, traps pathogens
What leukocyte is first one cite with contained pathogens?
neutrophils
colony-stimulating factor
secreted by macrophages and T-cells - increase neutrophils and eosinophils
Monocyte function
cleanup and repair
Edema
compresses veins, reduces drainage
Specific immunity
directed against a specific pathogen,
uses memory cells and antibodies
Cellular Immunity
T-Cells
Directly attack and destroys foreign cells, can’t be reached by antibodies
Humoral (antibody-mechanical) immunity
B-Cells
Indirect antibodies assault the pathogen
Work during extracellular stage of infection
Antigens
molocules that trigger an immune reaction
Long term immunity
Results from production of memory cells
and antibodies - both defend against a second invasion
Memory cells
copies of specific T & B lymphocytes
Antiobides
Large protein molecules - bind and destroy specific antigens
Types of Immunity (2)
Innate
Acquired
Types of Acquired Immunity (4)
Natural ACTIVE
Natural PASSIVE
Induced (artificial) ACTIVE
Induced (artificial) PASSIVE
Innate Immunity
Genetic, present at birth
Naturally acquired active immunity
Developed after exposure to a pathogen - body produces antibodies or T cells
Natural passive immunity
Antibodies produced by mother and passed to fetus or nursing infant
Induced active immunity
developed after one is given a dosage of antigen - smallpox, flu, tetanus
Induced passive immunity
Antibodies administered to fight infection (ie snake bite antivenom) - use ready made antibodies
Antigen Presenting Cells (APCs)
cells which present antigen - damaged or viral infected cells
monocytes
Dendritic cells
B- lymphocytes
MHC - Major Histocompatibility Complex
ingest and digest invader antigen, insert a piece of antigen into MHC on surface of membrane
Cell-mediated immunity response
Activation of Cytotoxic T cells
Cell-mediated immune response begins with _____
activation of T Cells by antigen presenting call
What does cell-mediated immunity lead to
production of several types of T cells specific to the invader, destroys it
4 types of T cells
- Cytotoxic Killer T Cells (CK)
- Helper T Cells
- Suppresser T Cells
- Memory T Cells
Cytotoxic Killer T Cells
DIRECTLY attack antigens
Helper T Cells
Activate B Cells and T Cells
Suppresser T Cells
Inhibit B cells and T cells
Memory T Cells
react to antigen that has previously invaded
First step in T Cell activation
Helper T Cells
Which T Cells recognize antigen
Cytotoxic T cells
Which T Cells destroy infected Cell
Cytotoxic T Cells
Causative agent for AIDS
Human Immunodeficiency Virus (HIV)
Opportunistic Infections
Infections that occur more often or are more severe in people with weakened immune systems
4 types classes of immune hypersensitivity
I - Allergy
II - Cytoxic antibody-dependent
III - Immune complex diseases
IV - Delayed-type hypersensitivity, cell-mediated immune response, antibody-independent
Anaphylaxis
allergic reaction, shock is when poor blood circulation as a result deprives the body of oxygen and nutrients. Does not happen with most cases.
Self-tolerance in immune system
Ability of immune system to recognize self-produced antigens as a non-threat. Some immunotherapies for cancer require breaking self-tolerance mechanisms. Failure of this system includes transplants, IBD, multiple sclerosis, celiac, type 1 diabetes.
5 immunoglobulin types
IgG IgM IgA IgE IgD
GMAED
