Lecture 17 - Adaptive Immunity Flashcards
Innate Immunity AKA
Nonspecific Immunity
Adaptive Immunity AKA
Specific or Acquired Immunity
Difference between Innate and Adaptive Immunity
innate immunity is the broad lines of defense which one is born with and protects us from any kind of pathogen whereas adaptive immunity is aquired throughout one’s lifetime and works to protect us from specific pathogens
2 Types of Adaptive Immunity
- Antibody-Mediated/Humoral Immunity
- Cell-Mediated Immunity
Humoral Immunity AKA
Antibody-Mediated Immunity
Which type of adaptive immunity is best for protecting against extracellular pathogens?
Humoral / Antibody-Mediated Immunity
Which type of adaptive immunity is best for protecting against toxins?
Humoral / Antibody-Mediated Immunity
Which type of adaptive immunity is best for protecting against intracellular pathogens including viruses?
Cell-Mediated Immunity
Which type of adaptive immunity is best for protecting against cancer?
Cell-Mediated Immunity
Which type of adaptive immunity can attack transplanted tissues/organs?
Cell-Mediated Immunity
Which type of adaptive immunity reacts with antigens?
Humoral / Antibody-Mediated Immunity
antigen
foreign substance that induces an immune response
Antigen AKA
immunogen
-gen
producing
Epitope
Antigenic Detrminant
the portion of an antigen to which an antibody can attach
antibody AKA
immunoglobulin
Ig
immunoglobulin
antibody
Y-shaped proteins produced by the body for immunity which bind to antigens
How many antigen binding site does an antibody have?
2
hapten
small molecules which can bind to a larger carrier molecule (i.e. a protein) to form a complete antigen and elicit an immune response
Describe the appearance and components of an immunoglobulin?
Y shaped.
Each half of the Y has a longer “heavy chain” and a shorter “light chain” of peptides.
The tips of the heavy and light chains (the tips of the Y) are the variable components which bind to antigens. The constant components determine which class of antibody it is.
Name the 5 Classes of Antibodies
IgG
IgM
IgA
IgD
IgE
Which 3 Classes of Antibodies are Monomers?
IgG
IgD
IgE
Which Class of Antibodies Can Act as a Monomer or Dimer?
IgA
Which Class of Antibodies is a Pentamer?
IgM
(pent=5 and the letter M has 5 points)
Which antibody is the most prevalent in the blood?
IgG
Which antibodies can activate complements?
IgG
IgM
Which antibody can cross the placenta?
IgG
What % of serum antibodies are IgG?
80%
How can an IgG protect against viruses?
it can bind to a virus and prevent it from binding to a host cell
What % of antibodies in the serum are IgM?
5-10%
Which Antibody is normally produced the very first time you encounter a new pathogen?
IgM
What % of antibodies in the serum are IgA?
10-15%
IgA is very prevalent in which body secretions?
Mucous, Breast Milk, Tear, Colostrum
Which immunoglobulin is important in allergic reactions?
IgE
Which immunoglobulin protects against worms and protozoans?
IgE
Does IgE activate complement?
no
Does IgE cross the placenta?
no
Where is IgD sometimes found?
Attached to B Cells
Where do Lymphocytes stem from?
Stem Cells in the Bone Marrow
Name the 3 Types of Lymphocytes
- Natural Killer (NK) Cells
- T Cells
- B Cells
What determines if a lymphocyte becomes a B or T cell?
T Cells will mature in the Thymus.
B Cells will mature in the Bone Marrow.
proliferation
a large increase in numbers
Clonal Selection
when a specific antigen is encountered the specific B cell with corresponding receptors will proliferate
Memory B Cells
long-living specialized B cells which can recognize the same pathogen which triggered their formation and colonize to produce more plasma cells with specific antibodies against it
Plasma Cells
B Cells which produce and secrete antibodies
Lifespan of a Plasma Cell
4 Days
How is it that we can produce antibodies against billions of different types of antigens?
genes in DNA coding for antibodies can rearrange
Clonal Deletion
The process through which a new lymphocyte is tested to ensure it doesn’t bind to any of your body’s normal receptors. If it binds to one of your own receptors (self-reactive), it is destroyed.
When self-reactive lymphocytes are not destroyed and go into the rest of the body, it causes ________.
Autoimmune Diseases
autoimmune disease
disease caused by the immune system mistakenly attacking normal, healthy cells/tissues
agglutination
when one antibody binds to two pathogenic cells
What process can help a capsualted bacteria be phagocytized?
opsonization
neutralization
when enough antibodies bind to the virus or toxin so that the virus/toxin cannot bind to a host cell
ADCC
Antibody-Dependent Cell-Mediated Cytotoxicity
Explain how antibody-dependent cell-mediated cytotoxicity works?
When there is a pathogen (i.e. a parasite) that is too large for phagocytosis:
- Antibodies will bind to the epitoes on the pathogen.
- Leukocytes (i.e. Eosinophils, Macrophages, NK Cells) then bind to the antibodies attached to the pathogen and release lytic enzymes such as perforin onto the pathogen to destroy it.
How is complement intially triggered?
complement is triggered directly by a pathogen or indirectly when antibodies bind to the surface of a pathogen
hypersensitivity reaction
an immune response which is more damaging than good
Where in the body is the Thymus?
behind the sternum
APC
Antigen-Presenting Cell
Two examples of antigen-presenting cells.
- Macrophages
- Dendritic Cells
Describe how an Macrophage can act as an Antigen-Presenting Cell
The macrophage will digest a pathogen then present a piece of the pathogen on it’s surface (as an MHC molecule) with an antigen. This presented portion can then bind to a receptor on a T-Cell.
What are the 3 Types of T-Cells
- Helper T Cells
- T Cytotoxic Cells
- T Regulatory/Suppressor Cells
CD4 Cells AKA
Helper T Cells
Function of Helper T Cells
- help activate B Cells (clonal selection)
- help macrophages respond to antigens
Function of Cytotoxic T Cells
release Perforin and Granzyme to directly destroy pathogens
Function of NK Cells
release Perforin and Granzyme to directly destroy pathogens
3 Functions of Regulatory T-Cells
- combat autoimmunity by inhibiting self-reactive T cells
- protect bacterial flora from the immune system
- protect an embryo and fetus from immune attack
cells primarily responsible for immune response intiated from a vaccine
Dendritic Cells
4 Types of Acquired Immunity
- Naturally Acquired Active Immunity
- Naturally Acquired Passive Immunity
- Artificially Acquired Active Immunity
- Artificially Acquired Passive Immunity
What type of Acquired Immunity occurs when an unvaccinated child gets sick with chicken pox?
Naturally Acquired Active Immunity
What type of Acquired Immunity occurs when antibodies are passed from mom to baby through the placenta?
Naturally Acquired Passive Immunity
What type of Acquired Immunity occurs when antibodies are passed from mom to baby through breast milk?
Naturally Acquired Passive Immunity
What type of Acquired Immunity occurs when one is vaccinated?
Artificially Acquired Active Immunity
What tpe of Acquired Immunity occurs when antibodies (i.e. antivenom) are injected into a patient?
Artificially Acquired Passive Immunity
Difference Between Active and Passive Immunity
In active immunity, the body is exposed to an antigen and in response produces the antibodies. In passive immunity, antibodies are given to the person.
SCID
Severe Combined Immune Deficiency
a defect in both B and T cells
Two Methods to Treat SCID
- Bone Marrow Transplat
- Gene Therapy
Hypogammaglobulinemia
abnormally low concentrations of all types of immunoglobulins in the body
AIDS & HIV target ________.
CD4+ T Cells
Attenuated Microbes
microbes that have lost their ability to confer disease due to the age of the microbe
Live-Attenuated Vaccine
a vaccine containing live attenuated microbes which are unable to cause disease but can instigate the body to produce antibodies
Inactivated or Killed Vaccines
vaccines of killed microbes
What type of vaccine is MMR?
Live-Attenuated Vaccine
What type of vaccine is the chicken pox vaccine?
Live-Attenuated Vaccine
Sub-Unit Vaccine
vaccine of only a part of the pathogen rather than the whole pathogen
Nucleic Acid Vaccines
uses genetic material from a pathogen to stimulate immunity