x Micro, 6, Principles of Immunology Flashcards
Bacterial Growth
LAG: no cell division, getting ready
LOG: Active phase. UP cell div
STATIONARY: plateau
DEATH: dying
Antigens
- body recognizes them as foreign substances and body makes antibodies in response
- provoke specific response
Antibodies
soldiers against antigens
-HI molecular weight >100,000 daltons
Haptens
- LO molec weight
- haptens bond w protein in body to form hapten carriers that induce immune response
(little guy hapten needs to be piked up by carrier protein to be big enough to elicit immune response.
Epitopes
Antigenic Determinants: chem structure on antigen that body does not recognize as self.
humans recognize each other by face, no face, we don’t know person.
Types of Antigens
- Autoantigens (self)
- Alloantigen (found in members of same species)
- Heterophile Antigens (identical antigen found in cell of diff species)
Bacterial Antigens
Somatic: found in cell walls
Capsular: found in bacterial capsule
Flagellar (H): found on flagella
Exotoxins: protein substances that are antigenic
2 Major branches of Immune System
Antibody-mediated (humoral) (b-lymphocytes)
Cell-mediated (t-lymphocytes)
B-cells vs T-cells
B-Lymphocytes:
- Human bone marrow
- antibody-mediated (humoral)
- Differentiated to form plasma cells (specialized)
- form memory cells
T-Lymphocytes
- thymus/trachea/thyroid area
- cell mediated immun
Lymphocytes made from
stem cells in bone marrow
Cell mediated Immunity
- depends on activity t-lymphocytes
- T-lymphocytes longer life than B-lymphocyted
- T found in same lymphatic tissue as B
- T react w certain antigenic determinants and become immunologically committed.
- part of commitment is conversion to a subset of cells called cytotoxic T-lymphocytes
Cytotoxic T-Lymphocytes
- toxic to cell
- do NOT make antibodies
- leave lymphatic tissue and enter circulation.
- circulate thru blood, gather at infection site.
T-Lymphocytes
- secrete lymphokines
- lymphokines are a type of cytokine
- interluekin-1 activates T-lymph causing growth and form clones.
Helper T-Lymphocytes
encourage B-Lymph to make antibodies
Suppressor T-Lymp
-Regulate (suppress) immune response so not excessive
Natural Killer (NK) cells
T-lymph that detect and destroy target cells without being exposed to antigens
Delayed hypersensitivity T-lymp
fx in hypersensitivity reactions and encourage local tissue inflamm
Humoral Immunity
Antibody Mediated Immun
- B-lymph activated and differentiated to make plasma cells. make specific antibodies against specific antigens
- antibodies aka Immunoglobulins
- other B-lymph make memory cells (for long term immun)
Antibody Structure
4 protein chains
- connected by 4 S bonds
- FAB region: outer end that attaches to binding site
-FC (Stem) region: activates complement system and encourage phagocytosis
5 classes of Antibodies
IgM IgG IgA IgD IgE
(MGADE)
OR GAME D (in order of percentage in serum HI - LO)
IgM
- Primary response in adults
- first to appear
- formed in fetus
- most reactive
- usually in blood not cells
IgG
secondary immune response
- most common in blood, also secretions
- crosses PLACENTA
- Natural Passive Imm
- 4 protein/2 bonding sites
IgA
- in external secretions
- mucous mem respiratory, gi, urogenital
- tears, saliva, bile, urine, colostrum, breast milk
- resists infections at body surface
IgD
- LO quantities in serum
- found on surface of B-lymph
- antigen receptor
IgE
- VERY LO in serum
- allergic reactions
- hypersensitivity reaction
- anaphylactic reactions
- worm infections
Primary Antibody Response
- after initial contact w antigen, no antibodies detected for 4-7d
- IgM first appear
- IgG after 10-17d
- antibody titer, amt of antibody in serum
Secondary (Repeat) Antibody Response
- weeks/years later
- more rapid than primary
- response
- peaks 2-7 days, lasts many days
- due to B-memory cells
- mostly IgG
Antibody Response
Day 1: primary initial exposure Day 7: IgM detected Day 15: IgG peak Day 21: second repeat exposure Day 60: IgG + IgM spike
some antibodies react with bacterial surface
encourage phagocytosis
when antibodies react w virus
virus cannot attach to host cell to replicate
what reaction is set off when antibody reacts with antigen?
Complement system, resulting in formation of attack complex and UP phagocytosis
Antibody reactions w toxin molecules…
neutralize toxin
Complement System
- Classical Pathway: highly specific immune system
- Alternative pathway: non specific
Active Immunity
Body makes it, long lasting, hours to develop
Natural Active
body makes from disease
Artificial Active
body makes after vaccine
Passive Immunity
body received antibodies from outside source
Natural Passive
baby from mother
Artificial Passive
injection of antibody
Attenuated Vaccine
- live, lifelong immunity
- Sabin Polio, Measles, Mumps, Rubella
Inactive Vaccine
- dead microbes
- Rabies, Flu, Salk Polio, Cholera
Subunit and Conjugate Vaccine
- fragments of microbes
- recombinant HEP B
Toxoids
- used when toxins produced by microbes are cause of disease
- inactivating toxin
- Diptheria, Tetanus
4 Types of Hypersensitivity Reactions
I: Anaphylactic Hypersensitivity
II: Cytotoxic Hypersen
III: Immune Complex Hyper
IV: Delayed Hyper
I - III: antibodies involved
IV: T-lymphocytes involved
4 Types of Hypersensitivity Reactions
I: Anaphylactic Hypersensitivity
II: Cytotoxic Hypersen
III: Immune Complex Hyper
IV: Delayed Hyper
I - III: antibodies involved
IV: T-lymphocytes involved
Anaphylactic Reactions
- Immediate, systemic reaction
- 2-30min after expose
- IgE (allergy) antibodies
Cytotoxic Reactions
- immediate hypersensitivity
- Involve IgG and IgM an d complement
- complement activation causes destruction of local tissue cells
Cytotoxic Reactions
- immediate hypersensitivity
- Involve IgG and IgM an d complement
- complement activation causes destruction of local tissue cells
Autoimmune Reactions
antibodies working against body’s own cells
- Drug-induced Immune Thrombocytopenia (DIT): Decreased platelets (<100,000), petechiae, hemorrhage
- Agranulocytosis: decreased WBCs (neutrophils), Immunosuppressed
- Hemolytic Anemia: decreased Hgb/Hct, Fatigue
Immune Complex Reactions
IgG of IgM antibodies and antigens deposited into wall of blood vessel.
- activate complement system and attracts inflammatory cells (neutrophils)
- enzymes from neutrophils cause damage to endothelial cell of the basement membrane
Immune Complex Reactions
IgG of IgM antibodies and antigens deposited into wall of blood vessel.
- activate complement system and attracts inflammatory cells (neutrophils)
- enzymes from neutrophils cause damage to endothelial cell of the basement membrane
Cellular Reactions
- Delayed hypersensititivity (1-2 days to develop)
- Tcells involved, secrete cytokines that attract macrophages
- PPD test (read 48-72hrs)
Cellular Reactions
- Delayed hypersensititivity (1-2 days to develop)
- Tcells involved, secrete cytokines that attract macrophages
- PPD test (read 48-72hrs)
Types of tissue Grafts
- Autograft: own tissue
- Isograft: identical twin tissue
- Allograft: tissue from another person
- Xenotransplantation product: non human tissue
- Graft-versus-host disease: transplanted cells cause cell mediated (t cell) immune response against host tissue.
Types of tissue Grafts
- Autograft: own tissue
- Isograft: identical twin tissue
- Allograft: tissue from another person
- Xenotransplantation product: non human tissue
- Graft-versus-host disease: transplanted cells cause cell mediated (t cell) immune response against host tissue.
Immune Deficiency Disease
- Congenital : due to mutations
- Latrogenic: immunosuppresive drug
- Selective Bcell immunodeficiency (B lymph): abnormal production of antibod may be result of liver disease, SLE or malignancies. Decreased ability of B Lymp to make antibodies.
IgM
5-10% of all antibodies in serum, pentamer structure, responsible for blood transfusion reactions
IgA
10-15% of antibodies in serum, most common antibody in mucous membranes, prevents the attachment of microbial pathogens to mucosal surfaces
IgE
0.0002% of antibodies in serum, greatly increases during allergic reactions and parasitic infections
IgG
80% of all antibodies in serum, can cross placenta to confer passive immunity
IgD
0.2% of antibodies in serum, no well-defined function
What is it called when IgG antib bind to attachment site of microbe, blocking host site from attaching and carrying out their fx
Neutralization
Why are 98% of T cells weeded out?
to prevent cells who can not recognize self-molecules from maturing
What do T regulatory cells do?
- protect fetus form rejection by body
- combat autoimmunity by suppressing non recognizing self-molecules.
- protect good bacteria in gut from being removed by immune system
Artificially acquired passive immunity
Injection of antibodies
Artificially acquired active immunity
vaccines
Naturally acquired active immunity
exposure to illness
Naturally acquired passive immunity
breast milk / transplacental transfer
Type I
Anaphylactic Hypersensitivity
Anaphylaxis occurs
Type II
Cytotoxic Hypersensitivity
Complement is activated by IgG or IgM with an antigenic cell, cause of blood transfusion reactions
Type III
Immune Complex Hypersensitivity
Caused by IgG, cause glomerulonephritis, cause transient inflammatory reactions
Type IV
Delayed Hypersensitivity
Transplant reactions, caused by T cells and cell mediated immune response,
I. Anaphalactic
Involve IgE, Mast cells, Basophils
II. Cytotoxic
Involve IgG, IgM, Complement, Target cells
ELISA
confirmed with Wester Blot
IV. Delayed cell mediated
Involve T-cells, Macrophage to kill target cells
I. Anaphalactic
- w/in 2-30min after exposure. IgE bind to MAST cells and BASOPHILS filled w mediators.
- Histamine/Prostaglandins - UP mucous, redness, heat
- Leukotrienes - contraction (i.e. asthma), constrict BVess = UP BP
Tx: Epinepherine
*HayFever: Up Resp Sys
Asthma:Lower RS
*8 foods cause 97% allergies (eggs, peanuts, tree nuts, milk, soy, fish, wheat, peas)
II. Cytotoxic
- Activation of Complement
- IgG or IgM with Antigenic cells cause lysis of cell (Transfusion)
- Directed against antigen on cells of surface of tissue
III. Immune Complex
- involve Antigens/Antibody complex that causes damage to cells
- 2-8hrs: Antib against antigens circulating in blood. Antigens small enough to escape phagocytosis. Complex become trapped under cell = inflammatory tissue. GLOMERULONEPHRITIS
IV. Delayed cell mediated
- mainly T-CELLS Sometimes MACROPHAGES
- called delayed because not apparent for a day or so. (ie. allergies to nickel, poison ivy, latex)
- Patch test to determine cause of Type IV
- reactions ONLY happen to those already exposed to antigens
AutoImmune Responses
Immune sys loses self tolerance = production of antibody and Tcell
Types of AutoImmune Responses
1) Cytotoxic - antib react w cell surface antigen (i .e. Myasthenia Gravis)
2) Immune Complex - deposition of immune complex = tissue damage. Most damage from Lupus in kidneys. (i.e. rheum arthritis,Lupus)
3) Cell mediated: T cell involved. (i.e. MS tcells and macrophage at nerve
s sheath.
Mast Cells
filled wth chemical mediators including histamine
Gram POS COCCI
- StrePtococci (P - POS) (Streptococcus pneumonaie, Pneumonia)
- StaPhylococci (P-POS)
- Lactococci
- Viridans
- Enterococci
L lactocci
O
V Viridans
E Enterocci
Gram POS BACILLI
- Actinomyces
- Bacillus
- Clostridium (Botulism)
- Cornybacterium (DIPTHERIA)
- Listeria
A Actinomyces
B Bacillus
C Clostidium (Clostridium food poison)
C Cornybacterium (DIPTHERIA)
Gram NEG COCCI
-Neisseria (NEG)
Gram NEG BACILLI
- SalmonELLA
- ShigELLA (Shigellosis)
- KlebsiELLA
- LegionELLA (Legionaire’s, Pontiac Fever)
- BordetELLA (Pertussis, Whooping Cough)
- BrucELLA (from animals)
- FrancirELLA
- PasteurELLA
- E.Coli
- Vibrio Cholerae (Cholera)
- Campylobactor
- Helicobacter, Pseudomonas
- Bacteroider, Hemophila, Yerjiiui?
Used to treat Pneumocystis pneumonia. Common in AIDS pts.
Pentamidine Isethionate
