-
immune system functions
protect againt pathogen, foreign material, remove damged or dead cells, remove abnormal cells
-
Pathogens
- bacteria
- viruses
- worms
- fungi
- parasites
- protozoa
-
Pathologies
- incorrect immune responses
- autoimmune (type 1 diabetes)overactive immune responses
- allergieslack of immune response
- immunodeficiency disease
-
lymphoid tissues
- produce, store, process lymphocytes
- include:
- bone marrow
- lymph nodes= storage
- spleen,thymus- matuartion cells
- tonsils/ adenoids
- appendix
- peyers patches (GAIT)
-
Lymphatic system
- drain tissue
- filtering
- fat transport
-
lymph nodes
- remove impurities and pathogens from lymph
- lymphocyte sotrage and phagocytosis-chew down any debris
-
non specific immunity(innate)
- quick
- external defenses
- inflammation
- interferon-early response to viral infection
- natural killer cells
- complement system
-
specific-required
- slower but stronger
- T-cells
- B-cells
-
External defenses
- Physical barriers
- skinmucous membranesChemical Barriers
- stomach acidlysozyme is secreted fluids
-
- realease chemical signals such as histamine
- dilation causes phagocytes to area
- phagocytes (macrophages and neutrophils) consume bacteria and cell debris; tissue heals
-
what does histamine cause in the inflammation response
- increase blood flow to site
- increase permeability of capillaries
- increase WBC/ protein to site
- increase fluid (swelling)
-
Inflammation
tissue trauma-> histamine release -> pyremia-heat-> dilation of arterioles and capillaries-> increase capillary permeanility-> neutrphil in and out of blood vessel ( leukocytosis)-> inflammatory exudate-> monocyte and fibrin
-
inflammatory chemicals
- interleukins
- cause feverchange permeability of blood vessels Bradykinin- trigger pain receptors
- complement proteins
- cascade produce membrane attack complex breakdown of foreign cell
-
Cytokines
- chemical that activate cell
- trigger response
-
phagocytes
- ingest foreign cells and chemicals
- macrophagesneutrophilsNatural killer cells
- kill tumor and infected cells
- Cytokines mediate inflammatory response
-
antigen-presenting cells
- marks cell for helper T- cells
- mediate increased response
-
Natural killer cells
- kill infected cells
- attack some tumor cells
- secrete chemical signals
- interferon(a,b)prevent viral replicationinterferon (y)- activate macrophages and other immune cells
-
Interferon
released by infected cells to help prevent infection of other healthy cells
-
four steps in an immune response
- 1. identify foreign substance
- 2. communicate with other immune cells
- 3. coordinate response
- 4. destroy invader
-
Acquired (Specific) immunity
- target antigens
- cytokines regulate both innate and acquired immune responses
- T-cell and B-cell reaction
-
types of immunity
- active natural-immune response
- active acquired- ex-vaccinations
- passive natural- ex-breast milk
- passive acquired-give immune response
- ex gamma globulins (immune deficiency)
-
lymphocyte clones
- very specific to their virus
- response specific to create antibodies
-
steps in immune response
- naive lymphocytes-not stimulated
- antigen bind to specific lymphocyte clone
- clone expansion
- cells muliply rapidlybecome plasma,helper T and cytoxic cellsother cells becme memopry cells
- stronger faster response to 2nd exposure
-
specific immunity
- B-cells
- attack free virus antibody reactionTcells
- attack infected cells both systems turn on at same time
-
types of lymphocytes
- B-lymphocytes
- plasma cells-> secrete antibodies T lymphocytes -turn on whole specific response, can become 3 type of cell
- -helper T cells-> secrete cytokines cytotoxic T cells -> attack infected cells, kill offsurpressor T cells- limit response NK cells
-
B lymphocytes
- kill free viruses
- ammunoglobins attached to B cell. Bind virus on ammunoblobin to activate B cell.
- clonal expansion form plasma cells
- plasma cell produce antibodies ( bind free virus)
- memory cells
- faster, stronger secondary response opsonin-> antibody that sensititizes antigen to phagocytosis
-
during secondary immune response, antibody concentration in plasma _______
increases, dur to memory cells after first exposure
-
binding of anitbodied to antigens inactivate antigens by:
-
five classes of antibodies (aka immunoglobulins or gamma globulins)
- IgG- most common, secondary response IgG (more specific)
- IgA- in saliva, tears breast milk. not sure about function
- IgE-involved in allergic response. gets inlfammation
- IgM- primary response. More general
- IgD-surface of B cells- role unclear
- if have enough IgG put in you can help cure allergy
-
function of antibodies
- 1. activate B-lymphocyte
- memory cells and plasma cell secrete antibodies2.act as opsonin- increase phagocytosis
- 3.antigen clumping and inactivation of bacterial toxins
- 4.activate antibody dependent cellular activity
- 5. degranulation
- 6.activate complement
-
T cells
- T lymphovytes-defend against intracellular pathogens
- T cell receptors- recognize foreign antigens with major histocmpatibilaty complex (MHC) proteins
- MHC proteins - found on all body cells and vary in people
-
activation of T lymphocytes
- cell bind to T lymphocyte
- signal transduction activates it
-
MHC class 1 proteins
- on all nucleated cells of body
- Recognized by cytotoxic T cells
-
MHC class 2 proteins
- only on antigen presenting cells
- recognized by helper T cells
-
Functional roles of cytotoxic T cells
- kill infected cells
- release perforin- create holes in infected cells
- stimulate aptosis (cell suicide)
-
function of Helper T cells
- secrete cytokines
- fever
- increase number of B cells and T cells
Bind to B cells
-
factors affecting resistance to infection
- malnutrition
- pre-existing disease
- tissue injury
- stress
- state of mind
- genetic disorder
- horomone changes
- previous exposure
-
Immune disorders
- hypersensitivity
- overreaction to immunity
- automimmune
- imune against itselfIsoimmune
- immunity against other humansImmunodeficient
- immunity lacking
-
inflammatory response to allergen
pollen, dust-> overproduction IgE-> Affinity for basophils and mast cells -> Rupture mast cell, release histamine, seratonin and bradykinin-> local edema, swelling, congestion
-
Allergic responses
- immediate hypersensitvity
- occur w/in minutesmediated by antbodiesDelayed hypersensitivity
- occur after several days mediated by helper T cells and macrphages
-
Type I
- excess IgE bound to mast cells and activated y allergens
- inflammation
- ex: allergies
-
Type II
- IgM or IgG cause destruction of foreign cells
- cell lysis
- ex: blood incompatability
-
Type III
- immune complexex deposited in tissue and vessels
- inflammation and tissue destruction
- Ex: immune complexes- glomerulonephritis
-
Type IV
- sesnitized T lymphocytes release cytokines
- inflammation and tissue damage
- Ex: delayed- poison ivy, organ rejection
-
Delayed Hypersensitvity
- symptoms:
- increase eosinophilsredness, heat, swelling and itching runny nose, coughing sneezing wheezing and nasal congestion
-
Contact Dermititis
- acute or chronic allergic skin reaction
- causes:
- plants
- jewelry
- drugs
-
Asthma
- allergy induced vs exercise induced
- symptoms:
- difficulty breathingwheezinganxietycough
-
Immediate hypersensitivity
- ex: food allergies
- symtpoms:
- cramping, diarrhea vomitinghives, rashesrunny nose
-
Allergy shots
- increase production IgG
- IgG bind the allergen before it binds to IgE
- decrease allergic response
-
Hypersensitivity
- Anaphylaxis- severe allergic response
- causes:
- antibiotics
- Anesthetics
- Foods
- latex
- Vaccine
- bee stings
-
Anaphylaxis
- abnormal distribution of blood
- vasodilation, not providing enough blood to area
- release histamine-> blood vessel dilate and leak plasma-> blood pressure falls-> venous return to heart impaired-> cardiac output inadequate-> circulation drastically reduced
-
symptoms and tramwnt of anaphylaxis
- symptoms:
- itching throat, tongueswelling of face and throatTreatment
- epinephrine- vasodilatorcorticosteroids- cortisol break down immune responseantihistamines
-
Issoimmune disorders
- blood transfusion reaction
- symptoms of transfusion:
- chills/shiveringfeverhemolytic anemia
-
A and B antigens are ____________ while Rh antigens are _________
- naturally occuring
- acquired
-
which blood type is universal donor and universal recipient?
- Type O universal donor
- AB universal recipient
-
erythroblastosis
- Mother antibodies attack and destroy antigen on babies RBC
- only affect Rh-positive babies carried by Rh-negative mother
- treatment=tranfusion babies blood
- gamma globulins- fake antibodies
-
Organ transplants
- autograft-from oneself
- isograft-from twin
- xenograft-from animal
- allograft-from another person
-
Autoimmune disorders
- immune systme doesnt react to self antigens
- autoimmune usually restricted to specific tissue or organs
-
rheumatic rever
- strep infection
- ocur one to four weeks later
- antibodies attack bacteria and own tissue
- sypmtoms:
- fever, malaise , joint painmyocarditis
-
rheumatoid arthritits
- abnormal anitbodyattack own cells and tissues
- symptoms:joint pain and ulnar deviation
- treatment:
- corticosteroids/ anti-inflammatory needs surgical joint replacement
-
Type 1 diabetes mellitus
triggered by viral infections
-
Lupus Erythematosus
- cutaneous or systemic
- symptoms:
- butterfly rash
- joint pain/fever
- low blood counts
- weight loss
- dterioration of organs
- treatment= anti-inflammatory, analgesics
-
causes of immune deficiency disorders
- congenital/ genetic disorder
- bone marrow suppresion-chemotherpy and radiation
- imunosurpressants
- immunodeficiency (AIDS)
-
HIV
- retrovirus
- decrease helper T cells-> fewer B cells-> decrease toxic response
|
|