overview Flashcards
(33 cards)
A properly functioning immnune system will attack
dangerous non-self
2
dysregulated immnue response will respond to
- safe non-self–allergies
- self–autoimmune disorder
4 categories
pathogen categories
what is the difference between bacteria and virus
1.bacteria
2.virus
3.fungus
4.parasite
virus replicate inside a cell, bacreria replicate outside a cell
fact
immune response can result in life long immunity
2 types, difference
immune response
innate immunity: first line, fast but nonspecific
adaptive immunity: highly diverse and specific
3
major players in immune systems
organ and tissue
cells
molecules
2 categories
key organs and tissue
Primary (centeral) lymphoid organs: where immnue cells generate
-bone marrow
-thymus
Secondary (peripheral) lymphoid organs: where immune cells activated
-lymph nodes
-lymphatics (lymphatic system)
-spleen
-mucosal associated lymphoid tissues
-other diffuse and loosely organized areas
they are connected via circulatory system (blood and lymphatic)
origin of immune cells (leukocytes or white blood cells)
originate in bone marrow
all mature blood cells arise from hematopoietic stem cell (HSC)
through the process called hematopoiesis, in bone marrow
pluripotent (can generate all most all cell type) or multipotent (generate various cell type in a family)
still debating hematopoietic stem cell belongs to which
2 main lineages of immune cells
common lymphoid progenitor
common myeloid progenitor
lymphoid progenitor differentiate to
B/T cells
NK cells (one type of ILC)
ILC (innate lymphoid cells)
dendritic cells
myeloid progenitor differentiate to
1.granulocyte/macrophgae progenitor
nuetrophil
eosinphil
basophil
monocyte
mast cell
2.megakaryocyte/erythrocyte progenitor
megakaryocyte–>platelets
3.erythrocyte (red blood cell)
4.dendritic cells
erythroblast deferrantiate to erythrocyte
4(6)
function of cells in myeloid lineage
erythrocyte: carry oxygen, generate antimicrobial compounds (but not main immune cells)
granulocytes
-neutrophils: direct harm
-eosinphils: antiviral and antiparasite activity
-basophils/mast cells: inflammation/allergies, produce histamines
megakaryocytes:
give rise to platelets (blood clotting)
monocytes:
migrate to tissue and differentiate to macrophages
function to repair/remodel, destroy
pathogens, present antigens
histamine 组胺
3
what cell do phagocytosis
Macrophages
immature dendritic cells
neutrophils
what cell do antigen-presenting
most potent: dendritic cells (immature capture antigen, then mature and migragte to another location)
macrophages: can also present antigens to T cells
lymphocytes are ( ) but different sets carry different ( )
similar
clusters of differentiation (CD) on their surface
and their chracteristic
which cell responsible for adaptive immunity
T and B cells
highly sepcific
has receptors on cell surface
Receptor of B and T cells
B cell receptor: BCR, bound to membrane or secreted out as antibody
T cell receptor: TCR, bound to mmebrane
function
dendritic cells
bridge of innate and adaptive immnuity
involved in detecting infection
activate adaptive immunity
function
molecules in the immune system
signal molecules:
1. stimulate and direct adaptive immune responses
2. commnunicate between or inside cells
3. mediate interaction between cells
4. trigger changes in target cells
types of molecules in the immune system
- Secreted proteins: cell communication
1.cytokines: messenger proteins secreted by certain cells
2.chemokines: subset of cytokines that recruit specific cells to a site (ex. migrate of monocyte) - Receptors on the cell surface
- Intracellular signaling molecules (proteins) & transcription factors
- Antigens (Ag)
immnue responses against
protein (most), nucleic acid, polysaccharide, lipid, organic chemicals, drugs
receptor recognize epitope on Ag
timing, receptors, actions, response to repeat infection, components
Innate immunity
Timing:
first line of defense
fast, non specitic
Receptors:
encoded in the germline, inherited
limited number
unchanging
Actions:
induces local inflammation
Response to repeat infection:
same each time
Major component:
barriers (ex.skin), phagocytes (macrophages, neutrophils, dedritic cells，…), pattern recognition molecules
timing, receptors, actions, response to repeat infection, components
Adaptive immunity
Timing:
slower and develop
Recptors:
randomly generated receptros
huge diverisity
highly specific to individual molecules
Actions:
responsible for specific immune responses
clear infections
result in memory
Response to repeat infection
more rapid and effective with each subsequent exposure
Major components
T and B lumphocyts, antigen specific receptors, antibodies
what and result
PRRs and PAMPs
PRRs: pattern recognition receptors
PAMPs: Pathogen-associated molecular patterns
Activation of PRRs on cells can directly induce effector functions in these cells and amplify the immune response by production of inflammatory mediators (cytokines and chemokines)
dendritic cells
link innate and adaptive
travel from site of infection to local sencondary lymphoid tissue
interect and activate T cells
