Week 1-General immunology Flashcards
Hematopoiesis
Generation of blood components
Hematopoiesis
Generation of blood components
CD34
cell surface molecule on hematopoietic stem cells
EPO: erythropoietin
Cytokine that promotes development of erythrocytes
TPO: thrombopoietin
Cytokine that promotes dev of megakaroyotes
What do all blood cells come from?
hematopoietic stem cells
Where does hematopoiesis occur in the body
bone marrow, but starts out in yolk sac and fetal liver/spleen
What are the three major progenitor cells
erythroid/megakarocyte, myleoid, lymphoid
what does lymphoid progenitors develop into
B cells (plasma), T cells, NK
Three types of pathogenic mechanisms
exotoxin, endotoxin, direct cytopathic effect
Three types of pathogenic mechanisms
exotoxin, endotoxin, direct cytopathic effect
CD34
cell surface molecule on hematopoietic stem cells
EPO: erythropoietin
Cytokine that promotes development of erythrocytes
TPO: thrombopoietin
Cytokine that promotes dev of megakaroyotes
What do all blood cells come from?
hematopoietic stem cells
Where does hematopoiesis occur in the body
bone marrow, but starts out in yolk sac and fetal liver/spleen
What are the three major progenitor cells
erythroid/megakarocyte, myleoid, lymphoid
what does lymphoid progenitors develop into
B cells (plasma), T cells, NK
What does myeloid progenitors develop into
neutrophil, basophil, eoisinophil, dendritic, macrophage, mast
Three types of pathogenic mechanisms
exotoxin, endotoxin, direct cytopathic effect
what can platelets release
cytokines, chemokines, prostaglandings, enzymes, Growth factors–> recruitment, anti-microbial defense, wound healing, inflammation, dendritic and macrophage activation
Definsin
soluble, antimicrobial peptides that protects cells from infections
How do defensins work
disrupt viral membranes, crosslink viral glycoproteins to prevent fusion, inactivate membrane, prevent nuclear import of pre-integration complex into nucleaus–no viral transcription
What is a paneth
major source of defensin in small intestin
What are some receptors on a macrophage
Toll like receptors, mannose receptors, LPS receptors (CD14) complement receptors, scavenger receptors, glycan receptors
TLR4?
Binds to LPS on macrophage surface, sends signals to nucleus to activates genes for inflammatory cytokines
TLR3?
inside endosomes in the macrophage, recognize pathogen DNA
what are some inflammatory cytokines that are released by dendritic cells and macrophages activated through TLR signaling
IL1, IL6, TNFa, IFNy
What are released by infected cells via TLR signaling
IFNa, IFNB which act to prevent other cells around them from getting infected
Which cytokines cause fever
IL6, TNFa, IL1B
Which increase vascular permeability in endothelium
TNFa, IL1B
Which cytokine is responsible for systemic shock
TNFa
What does CXCL8 (IL8) do
recruitment of neutrophils and basophils to site of infection
What does IL12 do
NK cell activation
What does ILB do
Activate lymphocytes, local tissue destruction, fever, increase vascular permeability
What does TNFa do
Increase vascular permeability, can cause septic shock, fever, increase mobilization of metabolites
What does IL6 do
Fever, induced acute phase protein production by hepatocytes
How does shock happen
TNFa release, endothelial cells produce PAF, blood clotting that block off local vessels that prevent infection spread…if bacteria reaches blood, it leads to widespread release of TNFa, systemic edema, vital organ failure, death
Tell me about neutrophils
most effective and most abundate pathogen killer. more engulfing diversity and longevity than macrophages
