Studied by 16 people
What are the three lines of immune defense
Physical barrier, innate immunity, adapative immunity
What is the purpose of the physical barrier?
to deter and delay
What is the biggest difference between innate and adaptive immunity?
MEMORY and speed
Explain adaptive immunity in terms of speed and specificity
slow but specific
Explain innate immunity in terms of speed and specificity
rapid but no specificity or improvements
What are some examples of physical barriers?
cilia, skin, lysozomes in tears
What are the key players of the innate immune system?
Natural killer cells, lymphocytes, dendritic cells, neutrophils, monocytes/macrophages, eosinophils, basophils
What are the key players of the adaptive immune system?
T and B cells
What bridges innate and adaptive immunity?
Dendritic cells
What is humoral adaptive?
Adaptive immunity using antibodies to fight extracellular invaders
What is cell-mediated immunity?
adaptive immunity using antibodies to fight intracellular invaders
What is MOST important about neutrophils?
First phagocytic cell to attack and destroy invading bacteria
What do neutrophils use to destroy bacteria?
hydrogen peroxide, hypochlorite, bactericidal granules, lactoferrin
What is extravasation?
The process of neutrophils being recruited for inflammation
What cell is involved in extravasation?
neutrophils
What are the two receptors aiding in extravasation?
Selectin and integrin
What type of selectin is on the epithelium?
P-selectin
What type of selectin is on the neutrophil?
L-selectin
What type of integrin is on the endothelium?
ICAM-1
What type of integrin is on the neutrophil?
LFA1
What is the job of selectins in extravasation?
to slow the neutrophil to a roll
What is the job of integrins in extravasation?
to cause adherance so they squeeze through the vessel wall
If a bacterium is large, how do neutrophils help?
NETosis
What is netosis?
Neutrophils release a large extracellular trap that is sticky to trap the bacterium and kill it without ingestion
What is the first phagocytic cell to attack and destroy bacteria?
Neutrophil
What is the first line of defense against a virus or tumor?
Natural killer cells
What do natural killer cells use to kill viruses and tumors?
Perforin and ganzymes
What do monocytes differentiate into?
Macrophages
What are the two types of macrophages?
M1 and M2
What are M1 macrophages?
destructive macrophages
What are M2 macrophages?
tissue repairing macrophages
What innate immune cells are responsible for allergies?
Mast cells, eosinophils, basophils
What is a phagosome?
Fusion of cell membrane around microorganism (ingested)
What is a phagolysozome?
fusion of phagosome and lysozome
What are the five types of dendritic cells?
Langerhans, plasmocytoid, follicular DC, Classical DC1, Classical DC2
What two dendritic cell types are vital for antibody production?
Follicular DC and Classical DC2
What are Follicular DC and classical DC2 vital for?
anitbody production
What are langerhans dendritic cells?
Found in skin, use Birbek granules
What are Plasmocytoid and classical DC1 vital for?
inhibiting viral replication
What two dendritic cell types inhibit viral replication?
Plasmocytoid and classical DC1
If dendritic cells are overwhelmed, who is called in for help?
Complement proteins
How do complement proteins work?
They attach to an invading cell, forma pore, and destroy it via osmotic lysis.
What special process allows complement proteins to work?
C9 polymerization
What are the three pathways of complement proteins?
Innate, alternate, and classical
What is the innate pathway of complements triggered by?
MBL (mannose-binding lectin) binding to a microbe
What is the alternate pathway of complements triggered by?
C3b binding to a microbe
What is the classical pathway of complements triggered by?
antibody secretion
What is the complement C3e responsible for?
promoting leukocytosis
What complements are made by the liver?
C3, C6, C8, FB (3 shots, 6 shots, work in 8 hours, Bad for liver)
What complements are made by mast cells?
C1q
What complement cells are made by neutrophils?
C6,C7
What complements are made by macrophages?
C2, C3, C4, C5, FP, FD, FI, FB (pinching dogs is bad)
What is a PRR?
Pattern recognition receptor. Found on all host innate immune cells to detect PAMP and DAMP
What is PAMP?
Pathogen Associated Molecular Protein. Produced by pathogens
What is DAMP?
Damage Associated Molecular Protein. Produced by invaded cell.
What is the major type of PRR?
TLR (Toll-like receptor)
Where are TLR found?
Intracellular for viruses and extracellular for bacteria
What does TLR-4 do?
targets LPS
What does TLR-5 do?
targets flagellum
When a PRR comes into contact with a PAMP what happens?
Inflammation
When a PRR comes into contact with a DAMP what happens?
inflammation
When a PRR comes into contact with a PAMP and a DAMP what happens?
Inflammation
What does inflammation caused by a PRR and PAMP and/or DAMP lead to?
Cytokine production
What is produced by macrophages and dendritic cells?
Cytokines
What are the cytokines specific for inflammation?
IL-1, IL-6, TNF alpha, IFN gamma
What are the three routes of cytokine binding?
Autocrine, paracrine, endocrine
What is autocrine binding of cytokines?
the cytokines bind to the same cell that released them
What is paracrine binding of cytokines?
The cytokines bind to neighboring cells
What is endocrine binding of cytokines?
the cytokines travel long distances via the blood stream to bind to cells
What are the four types of cytokines?
interferons, interleukins, TNF, chemokines
What is the job of chemokines and the most important chemokine?
to attract neutrophils for extravasation by CXCL-8
How do Humera and Enbrel work?
These drugs inhibit TNF receptors to decrease inflammation in diseases like Rheumatoid Arthritis
Explain the steps of signal transduction
cytokine binds ton receptor
kinase activation
second messengers activated
generation of new transcription factors
gene activation/ modification of cell behavior
What is signal transduction?
an extracellular signal being transformed into an intracellular signal
What are the two antigen-presenting structures?
MHC class 1 and MHC class 2
What is MHC class 1?
Used on NON-immune cells to alert to INTRACELLULAR/ENDOGENOUS invader
What is MHC Class 2?
Found on host immune cells after they have captured and processed the antigen. They degrade the antigen and create an MHC complex that is transported to cell surface
Where must MHC class 2 receptors be transported to in the body to present to B cells?
Lymphoid organs
What are the two types of lymphoid organs?
Primary and secondary
What are the primary lymphoid organs?
Thymus, bursa/bone marrow/intestinal lymphnoid tissue
What are the secondary lymphoid organs?
lymph nodes and spleen
What is the job of primary lymphoid organs?
to produce B/T cells and train them
What is the job of secondary lymphoid organs?
help with antigen presentation
What occurs in the thymus?
production of T cells
What occurs in the bursa/bone marrow/ intestinal lymphoid tissue?
Production of B cells
What occurs in the lymph nodes?
dendritic cells present to T cells in medulla
What is the spleen responsible for?
filtering antigens from blood
What are the two types of lymphocytes?
T and B cells
Where do T and B cells mainly reside?
lymph node and spleen
Can lymphocytes be differentiated on a histologic slide?
NO because they are all the same size/shape
How can we differentiate lymphocytes?
cytometry
What is a CD?
Marker on lymphocyte for identification (in addition to PRR and TCR/BCR)
What does CD stand for?
Cluster of differentiation
What are the two CD categories?
CD or WC
What is a WC CD?
A cluster of differentiation found only in one species (no homolog)
What is often the CD homolog for humans?
mouse
What is the purpose of a CD?
to help us identify the lymphocyte
How do adaptive immune cells recognize bacteria and viruses?
antigens
What are the two types of antigens?
immunogens and haptens
What are immunogens also called?
complete antigens
Note 
Flashcard (24)