Introduction to Immunity and Hematopoeisis (Exam 1) Flashcards
What are the two arms of the immune system?
adaptive
innate
What is innate immunity
the frontline of defense
active the first time you contact an antigen; fights off antigen enough to allow adaptive immune response to develop
What is adaptive immunity
specific components of immune system
memory response, B cells, T cells
When is innate immunity acquired
born with it and doesn’t change throughout life
What branch of the immune system is the first line of defense against pathogens
innate
What are the characteristics of innate immunity
limited specificity and diversity
no memory
What is the difference between innate and adaptive immunity
innate has no memory and is less specific
innate is present at birth and is unchanged throughout life, while adaptive develops with time
Why is it important that adaptive immunity be self limiting
prevent autoimmune events; avoids destroying healthy tissues
What are the two main components of adaptive immunity
T lymphocytes
B lymphocytes
When will innate and adaptive immunity be active
innate: immediately
adaptive: 10-14 days after innate response (when the antigen threshold is reached)
Where does hematopoiesis occur throughout life span of an individual
begins in yolk sac, migrates to fetal liver and spleen and ultimately bone marrow
What can occur if hematopoiesis from bone marrow isn’t sufficient
can revert back to spleen and liver
Reverting hematopoiesis back to the spleen and liver can cause what
splenomegaly and hepatomegaly leading to rupture
What is a clinical example of reverting back to spleen or liver for hematopoiesis
Myelofibrosis
What does Myelofibrosis cause
bone marrow to turn into scar tissue thus preventing hematopoiesis
What type of cells initiate hematopoiesis in the bone marrow
pluripotent hematopoietic stem cells (PHSC)
What do pluripotent hematopoietic stem cells (PHSC) develop into
all cells of the blood lineage (red and white)
What is a characteristic of pluripotent hematopoietic stem cells
self renewing
A patient is undergoing radiation treatment. How will this effect her PHSCs and immune cells
PHSC will be resistent due to slow turnover
immune cells would be sensitive as they divide more rapidly
What do lymphoid stem cells give rise to
B lymphocytes
T lymphocytes
NK cells
What branch of immunity is NK cells involved with
innate immunity
What do myeloid stem cells generate
Red and white blood cells
A patient comes to the office with a bacterial infection. What type of blood cell will be elevated in this patient
neutrophil
What is the most common WBC
neutrophil
When will a spike in eosinophils be seen
parasitic infection and allergies
What is a band cell
immature neutrophil
Why is it essential to match MHC in bone marrow transplants
to prevent graft rejection, donor cells may not recognize recipients cells as self
In what order will cells enter in an acute inflammatory response
neutrophils first
monocytes second
lymphocytes third
What does SCID stand for
severe combined immunodeficience
What causes SCID
no B cells or T cells (lack of adaptive immunity)
What is ADA deficiency
Adenosine deaminase deficiency
What does ADA lead to
SCID
How is ADA deficiency fixed
pull out stem cells, put in good copy of ADA gene using retrovirus, grow, infuse back into patient
How are lymphocytes differentiated
CD markers
What recognizes CD markers
monoclonal antibodies
Where will CD4 markers be found
T helper cells (TH)
Where will CD8 markers be found
T cytokine cells (TC)
Where will CD3 markers be found
All T cells
Where will CD14 markers be found
Macrophages
What markers are found on NK cells
CD16 and CD56
What markers will be found on B cells
CD19, 20, 21
Where will CD34 markers be found
Stem cells
Where will CD40 markers be found
antigen presenting cells
Where will CD40L marker be found
activated T helper cells
What are the lymphoid cells of the immune system
B cells
T cells
NK cells
What are the mononuclear cells of the immune system
macrophages
granulocytes
dendritic cells
What are the granulocytes of the immune system
neutrophils
eosinophils
basophils
mast cells
What cell will be increased during a bacterial infection
neutrophils
When will there be a spike in lymphocytes
during viral and intracellular bacterial infections, fungal infections
When will monocytes spike
mononucleosis and listeria monocytogenes
What is the percentage of neutrophils
50-70
What is the percentage of lymphocytes
20-40
What is percentage of monocytes
1-6
What is the percentage of eosinophils
1-3
What is the percentage of basophils
<1
What is the number of RBC
5x 10^6
What is the number of platelets
2.5 x 10^5
What is the number of leukocytes
7.3x10^3
What will happen once a B cell comes in contact with Antigen
undergoes cell cycle
enlarges
differentiates into memory and effector cells
What are naive lymphocytes
resting cells that have not interacted with an antigen
What cell cycle phase are naive lymphocytes in
G0
How are lymphoid cells self limiting
if they do not find antigen within a month they will die off
Where do B lymphocytes complete development
bone marrow
What is the function of bound Ig on B cells
serves as receptor for antigen
What do B cells develop into
plasma cells and memory cells
What do all clonal progeny of B cells secrete
Ab molecules with the same Ag binding specificity
What cells secrete antibody
plasma cells
What are plasma cells
terminally differentiated B cells
Where do T cells mature
thymus
What is the purpose of T cells maturation in the thymus
learn how to identify self vs non self, if it cannot, the cell will be destroyed
What is the function of TCR on T cells
recognize Ag in association with a MHC molecule
What receptors will be found on a T helper cell
CD4 and CD3
What receptors will be found on the surface of cytotoxic T cells
CD8 and CD3
What are the two subsets of T lymphocytes
T helper cells
T cytokine cells
What is the function of CD4+ T cells
send signals to other cells to make them kill pathogens
What is the funciton of CD8+ t cells
kill the pathogen or infected cell
What antigen association to cytotoxic t cells recognize
Class 1 MHC (endogenous antigens)
Which type of T cell directly recognizes and kills target cells
cytotoxic t cells
What cell can perform the tasks of a cytotoxic T cell if it is not available
NK cells
What receptors are found on NK cells
Ab (CD16) ADCC
What will happen in an individual with Chediak-Higashi
increased incidence of lymphomas: due to no NK cells
albinism: affects monocytes
What do NK cells have cytotoxic activity against
wide array of tumors
What is lacking in a NK cell
B and T cell markers and specific receptors for Ag
What type of cell will NK cells destroy
any cell that lacks class 1 MHC
What are NK cells derived from
lymphoid stem cells
Where are monocytes and macrophages found
monocytes- blood
macrophages- tissue
Where do monocytes develop
bone marrow
What occurs to monocytes after development
enter the blood where they further differentiate into mature monocytes
How do macrophages form
monocytes circulate in blood for 8 hours, then migrate to the tissue to mature into macrophages
What is the main job of a monocyte
phagocytose
Where is CD14 found
macrophages and monocytes
What are macrophages within connective tissue called
histiocytes
What are macrophages within the liver called
Kupfer cells
What are macrophages within the kidney called
mesangial cells
What are macrophages within the brain called
microglial cells
How is macrophage activity increased
activated by IFN gamma from T helper cell
How will an activated macrophage be different from a resting macrophage
increased phagocytic activity
ability to activate TH cells
higher levels of class 2 MHC on cell surface
What is the life cycle of a neutrophil
form in BM
released into blood
migrates 7-10 hours then to a home tissue where it has a lifespan of 3 days
What will be released from the BM in response to an infection
neutrophils: leukocytosis
What is the first cell to site of infection
neutrophils
What type of cell is involved in pus formation
neutrophils
How is pus formed
neutrophils die after phagocytosing pathogen, and then create pus
What cells are increased in an infection with a worm
eosinophils
What reaction are eosinophils involved in
type 1 hypersensitivity
What is contained within the granules of eosinophils
proteins that will kill parasites by damaging their membranes
WHat is the function of basophils
acts during allergies
What is contained within granules of basophils
histamine and eosinophil chemotactic factor
Where do mast cell precursors differentiate
when they leave blood and enter the tissue
When will mast cells be increased
allergies
What is the function of dendritic cells
antigen presenting
after capturing Ag in the tissues, migrate to the blood or lymph and circulate to various lymphoid organs where they present Ag to T cells
What is expressed in high levels on dendritic cells
Class 2 MHC and B7
Where are follicular dendritic cells found
exclussively in follicles of lymph nodes
What is not expressed on follicular dendritic cells
class 2 MHC
What is the function of follicular dendritic cells
maintain the pool of memory cells, holds complexes of antigen and antibody on its surface for extended period of time, keeps memory of previous infections. allow memory pool to stay activated
