Week 1 Flashcards
(40 cards)
How properly functionning immune system works?
Key function:
Distinguishes between self and non-self (dangerous and self)
WILL mount a response only against dangerous non-self (pathogens)
Pathogens categories
Virus
Parasite
Bacterium
Fungus
Immune response are quickly tailored to the type of m/o involved (resp change depending on type)
Major factor for immune response is
Intracellular (replicate inside ¢-virus) VS Extracellular (replicate outside of¢-bacteria).. processed differently and generate diff response
Immune repsonse
Complex w/many mol, ¢,tissues over time and in diff locations…can result in life-long immunity
Immune rep= Innate+Adaptive
Innate immunity: first line of defense, fast, non-specific
Adaptive immunity: Diverse, highly specific
Major players in immune system
1-organs and tissus
2-Cell
3-Molecule
1-organs and tissue
Check pic #1
Bone marrow
Thymus
Lymphatics (lymphatic syst)
Lymph nodes
Immune cells travel in body and occupy diff tissue over time
2type of tissue: 1a)v Primary vs 1b) secondary
1a) Primary tissue
also called central tissue:
lympoid organs=where immune ¢ are generated:
Bone marrow and thymus
1b) Sceondary tissue
also called peripheral tissue:
lymphoid organs=where immune ¢ are activated:
-lymph nodes,
-spleen,
-mucosal associated lymphoid organized areas (malt)
Connected to e/o by blood and lumphatic circulatory sys
2-Cells
Innate:
neutrophils,
mast cells,
monocyte
Adaptive:
B-cell w/antibodies,
T-¢ (CD3+,CD4+(T helper cell)CD8+(T cytotoxinc cell)),
T regulatory ¢
Both:
Natural killer ¢
Dendritic ¢
Macrophages
2- Origins of immune cells
Immune ¢=leukocyte=white blood ¢
Origin: bone marrow (all start as hematopoietic stem ¢ (HSC))
Hematopoiesis: process from HSC to mature blood cells by differenciation (occur in bone marrow)
2 theory abt STEM CELL:
Pluripotent: generate almost every specialized ¢ type in an organism
Multipotent: generate ¢ in a family of related cells
2- From hematopoietuc stem cell
Common lymphoid progenitor–>
B-¢, T-¢, NK ¢, ILC (adaptive lymphoid ¢)
Common myeloid progenirot–>
granulocyte: neutrophil, eaosinophil, basophil, mast cell, monocyte (mast ¢and monocyte become macrophages later)
From myeloid and lymphoid progenitor: Dendritic ¢: bridges innate imm. to adaptive imm
From here ¢ go to reside in tissues and organs or cirlate in blood/lyphatic sys
2a) Myeloid lineage
Red blood cells (erythrocyte: carry O2 to ceel &tissue…can generate antimicrobial compounds)
GRanulocyte:
Neutrophile: direct haem to pathogens
Eosinophile: antiviral act, antiparastitic act
Basophils/Mast ¢: Inflammation/allergies
Megakaryocyte: give rise to platelets (blood clotting)
Monocytes: migrate into tissue and differentiate into macrophages-fct to repail/remodel, destroy pathogens, prensent antigens
MAcrophages, immature dentritic ¢ and neutrophils:
Immature dendritic ¢ capture antigen then mature and migrate out of that location to another to present antigen to T-cell… they are the most potent antigen-presemtomg cels fro activating naive T-cells (never go back to immature)…thats how bridge
MAcrophages, immature dentritic ¢ and neutrophils
Specialized for phagocytosis (¢ uptake by engulfment)… MAcrophages can also presnet antigens to T¢
lymphoid lineage
B ¢
T ¢
NK ¢ (innate lymphoid ¢ subtype) & ILC
Lymphocyte appear similar but different set carry diff cluster of differenciation (CD molecule) on surface
B & T ¢
Check pic 3
respo for adaptive immunity
specific response because of highly specific receptors
B ¢ receptor (BCR): boudn to membrane or secreted as antibody
T¢ receptor (TCR): bound to membrane
DEndtritc ¢
Involved in detecting infection, activate adaprove immunity
3-Molecule
Cehck pic 4:
ACtivation of innate imm resp produce signal molecule that stimulate and direct adaptive immune cells
Can communicate (between or inside ¢) or mediate interaction between¢. trigger changes in target ¢ (ex:activation, signaling, migration, transciption, ¢ar diff)
Secreted P
REcepors on ¢surface
Intra¢ar signaling mol and transc factors
Antigens
SEcreted P
cytokine: messenger P secreted by certain ¢
Cehmokins: subset of cytokine that recreuit specific cell to a site
REcetpros on ¢surface
Cytokine/Chemokine bind to targetcell via specific receptors
¢ can interact w/ e/o thru receptors
Intra¢ar signaling mol and transc factors
Many stimuli can result in intra¢ar signaling, involving signaling P and transc factors
Antigens (Ag)
Mol that immune response are genrated against
Ag=any specific mol that can trigger an immune response
CAn be P (most), na,polysac, lipid, org chemical, drug
Specific portion of Ag recognized by receptor of immune ¢=epitope
Overview of immune response and phases of immune response
Check pic 5
Many phases to immune response
Take time
Innate immune repsonse is fast and lonly lasts days
Adaptive immune resposne take longer but lasts longer
Innate immune response
Exposure
Activation/Inflammation
Linking to adaptive
Exposure
thru our epithelial cell layer
Symbiosis and homeostasis for commensal bact dont attack
Immune ¢ PRR bind PAMP
Immune ¢ have many PATTERN RECOGNITION RECEPTORS (PRR): recognize self VS non-sef and broad categ of mol common in pathogen (PAMP)
PAMP: common foreign struc characterizing whole gr of pathogens not from host body (ex; dsRNA not in human/cell wallbac=lipolys)
¢activation/Inflammation
Check pic 6
ACtivation of PRR on ¢ (ex.macrophage) can directlu induce effector functions in these ¢
¢amplify repo by producing INFLAMMATORY MEDIATORS (chemokines(attract ¢ to a site) and cytokines(help inflammation))=vasodilation (permeability increase so ¢ can enter site of infection)=REDNESS, HEAT, SWELLING, PAIN***
