Ch.21: Immune System Flashcards
Characteristics of Innate Defenses
nonspecific first and second line of defense function the same way regardless of the invader
Innate systems of defense include:
Skin barriers and mucus membrane Antimicrobial proteins phagocytes and Natural killer cells inflammation fever
First line of defense includes
Skin and Mucous Membrane
Role of skin:
epidermis, keratinized, waterproof, and has hairs
Also excretes sweat and sebum
Physical barrier
Role of Mucous Membrane:
lines body cavities and secretes mucus
sticky and traps and filters microbes
Enzymes: lysozyme. found in saliva, respiratory mucus, and lacrimal fluid, Destroys bacteria
Defensins: control bacterial and fungal colonizatons in specific area
Second Line of Defense: Three main types of antimicrobial protein that discourage Microbial growth are:
interferons
complement proteins
transferrins
Characteristic of Interferons
inhibit viral replication by blocking protein synthesis and degrading viral RNA
family of immune modulating proteins
Characteristics of Complement Proteins:
normally circulate the blood in an inactive state
Majoring mechanism for destroying foreign substance in the body
Enhance immune responses by causing immune response by causing phagocytosis, cytolysis and inflammation
both innate and adaptive
Characteristics of Transferrins:
Iron-binding proteins that inhibit the growth of certain bacteria by reducing the amount of available iron
Characteristics of Natural Killer (NK) Cells:
“police” the body in blood and lymph,
10% of the lymphocytes in the blood are NK cells
a group of defensive cells
lyse and kill cancer cells and virus-infected body cells
nonspecifity, not phagocytic
kill by directly contacting the target cell and undergo apoptosis
Natural killer cells kill by attaching to the cell’s membrane and releasing _______ and _______
Perforin: creates perforations in cell membrane, results to cytolysis (cell rupture)
Granzymes: cause apoptosis (self-destruction)
_________ are specialized cells that perform phagocytosis
phagocytes
________ and ________ are the two principle phagocytic cells, they emigrate from vessels
Neutrophils and Macrophages
Five steps of Phagocytosis includes:
- phagocytes adheres to pathogens or debris (chemotaxis)
- phagocytes from pseudopods eventually engulfing the particle (adherence)
- fuses and forms a phagolysosome
- lysosomal enzymes digest the particles (digestion)
- Exocytosis of the vesicles removes the indigestible material (killing)
The inflammatory response has several beneficial effects including:
prevents the spread of damaging agents to nearby tissues
disposes of cell debris and pathogens
alerts the adaptive immune system
sets the stage for repair
Four characteristics signs of Inflammation;
Redness Heat Swelling Pain Fifth: impaired function
________ cells are a key component of the inflammatory response, release the potent inflammatory chemical HISTAMINE.
Mast cells
_________: abnormally high body temperature due to the resetting of the body’s thermostat (hypothalamus)
Fever
hormone released is Pyrogen
Elevated body temperature can:
intensify the effects of IFNs
inhibit the growth of some microbes
speeds metabolism and repair
Neutrophils migrate towards the site of inflammation by flattening and squeezing between the endothelial cells of the capillary walls, a process called ________
diapedesis
Chemicals act as a homing device
chemotactic agents: chemotaxis
Characteristics of Specific Resistance (immunity)
develops slowly over time in response to contact with specific invader
Activation of specific lymphocytes
It has a memory, its systemic, specific
_________ ability to carry out immune response when stimulated
immunocompetence
Two types of Lymphocytes:
B cells: red marrow, plasma cells, production of antibodies
T cells: red marrow, thymus, cell to cell
Two types of Immune Responses:
Cell-Mediated immune response
Humoral/ Antibody-mediated immune response
Characteristics of Cell-Mediated immune response:
T cells, directly attack invading antigen
effective against: fungi, parasites, viruses, cancer & foreign tissues
Characteristics of Humoral/Antibody-mediated immune response:
B cells: antibodies present
specific antibodies
bind to primarily extracellular targets: bacteria, toxins, viruses
Antibodies can:
neutralize toxins immobile bacteria cause agglutination work with complement proteins enhance phagosytosis
Not all B cells and T cells turn into either plasma cells or involved in cell to cell war, Some develop into B and T __________
Memory cells:
Which allows for memory to develop in immune responses much quicker and intense after a second or more exposure to an antigen
A measure of immunological memory is known as _________, which is the amount of antibody in plasma
Antibody titer
_________ can contained weakened or dead antigens or parts of antigens
Vaccines
______________: body does not recognize self. Examples are Multiple sclerosis (myelin sheath) and Rheumatoid arthritis ( connective tissue joints)
Autoimmune disease
________: oversensitivity to antigen
allergy
Characteristics of Humura/ antibody mediated immunity
provided by antibody, B cells,
bind primarily to extracellular target, inactivate and mark
Characteristics of Cellular immunity
cell to cell attack, T cells
Four major groups of T cells
Helper T cells: activation, most important
Regulatory T cells: inhibit attack, prevents autoimmune
Memory T cells: mount and prepare for next encounter
Cytotoxic T cells: kills directly, attack pathogens
Two types of Antigens
complete antigen: immunogenecity (stimulation) and Reactivity
Incomplete antigen: small molecules ( reactivity)
___________ encounter antigens and produce antibodies against them. Acquired naturally/ artificialy
Active humoral immunity
____________ ready made antibodies that are introduce to your body, naturally (fetus) or artificially (donor)
passive humoral immunity
_________ are not foreign or antigenic to you but they are strongly antigenic to other people, the identify of self is a group of glycoprotiengs
MHC Proteins
__________ get bacteria and experience the symptoms
Naturally acquired
__________ receive vaccines, pathogens that are dead or weakened
Artificially acquired
_________ results when the immune system damages tissue as it fights off a perceived threat
hypersensitivity
______ destroys helper t cells depressing the cellular immunity
HIV
