Block A: Innate Activation, B-Cells and T-Cells Flashcards
When were observations that people who recovered from a disease were “protected” against it first recorded?
430BC
(Lecture 1, Slide 3)
When was variolation first carried out?
The 15th century
(Lecture 1, Slide 3)
When was vaccination first carried out and by who?
1796 by Edward Jenner
(Lecture 1, Slide 3)
What was Edward Jenner’s experiment in 1796 testing?
The idea that people (in this case milkmaids) with cowpox did not get smallpox
(Lecture 1, Slide 3)
How did Edward Jenner in test the idea that people who had cowpox did not get smallpox?
He inoculated a boy with scrapings from a cowpox pustule (a small blister / pimple on the skin containing pus) and then deliberately infected the boy with smallpox. The boy survived even after 20 exposures
(Lecture 1, Slide 3)
What did Louis Pasteur do in the 1880s?
He injected old cultures of vibrio bacteria into chickens and found they survived cholera
(Lecture 1, Slide 4)
What did Louis Pasteur’s experiment in the 1880s lead to?
Concepts about phagocytes and factors such as antibiotics being discovered
(Lecture 1, Slide 4)
What 4 types of pathogens does the immune system have to deal with?
Bacteria
Viruses
Fungi
Parasites
(Lecture 1, Slide 10)
What is a microbiome?
A community of organisms living within us that has a symbiotic, beneficial relationship
(Lecture 1, Slide 10)
When does a microorganism become parasitic?
When they breach tissue, causing damage or illness
(Lecture 4, Slide 10)
What are 3 differences in microorganisms that showcase the diversity of pathogens the immune system has to deal with?
Intracellular vs extracellular
Differing sizes
Different locations
(Lecture 1, Slide 11)
What are 5 possible routes of infection?
Person to Person
Orally (through food)
Contaminated water
Vector
Fomites (non-living objects)
(Lecture 1, Slide 13)
What 2 different arms can the immune system be divided into?
Innate and adaptive
(Lecture 1, Slide 15)
What is the innate immune system composed of?
Composed of non-specific mechanisms innate (since birth) to the host organism
(Lecture 1, Slide 15)
What is the adaptive (acquired) immune system composed of?
Composed of responsive and specific mechanisms that can adapt to specific organisms
(Lecture 1, Slide 15)
What does non-specific mean in the context of the innate immune system?
It can protect against foreign invaders without having to specifically recognise them
(Lecture 1, Slide 16)
Does the innate immune system require previous exposure to invaders?
No
(Lecture 1, Slide 16)
How does the innate immune system recognise a cell / substance as foreign?
It recognises a general conserved property that marks an invader as foreign
(Lecture 1, Slide 16)
How long does the innate immune system take to respond to a breach?
Can occur within minutes
(Lecture 1, Slide 17)
What 2 ways does the innate immune system first respond to a breach?
Phagocytosis and inflammatory processes
(Lecture 1, Slide 17)
What are the 3 reasons that receptors are important in the innate immune system?
Recognise invaders
Recruit different cells
Help in production of proteins that facilitate destruction of pathogens
(Lecture 1, Slide 17)
What are the 2 antimicrobial proteins that are produced by the innate immune system?
Interferon and complement
(Lecture 1, Slide 17)
What is the name of the process in which phagocytes engulf and destroy particles?
Endocytosis
(Lecture 1, Slide 19)
msWhat are the 5 types of professional phagocytes?
Neutrophils
Monocytes
Macrophages
Mast cells
Dendritic Cells
(Lecture 1, Slide 19)
How do phagocytes move to an area they are needed?
Chemotaxis
(Lecture 1, Slide 19)
What are resident phagocytes called and where are they found?
Resident phagocytes are called sentinels and are found in most tissues
(Lecture 1, Slide 20)
What phagocytes are the first responders in inflammation?
Neutrophils (White blood cells)
(Lecture 1, Slide 20)
How do neutrophils respond within minutes to inflammation?
They are recruited to sites of infection
(Lecture 1, Slide 20)
What type of phagocyte arrives shortly after neutrophils in inflammation?
Macrophages
(Lecture 1, Slide 20)
What do mast cells produce?
Histamine
(Lecture 1, Slide 20)
How do dendritic cells have an important role late in the adaptive response?
They act as a bridge between innate and adaptive systems
(Lecture 1, Slide 20)
How does inflammation start?
Infected and injured cells release chemicals that stimulate inflammation
(Lecture 1, Slide 24)
What are the 2 purposes of inflammation?
To prevent the spread of infection and to heal damaged tissue following pathogen clearance
(Lecture 1, Slide 24)
How are phagocytes activated at the onset of infection?
By Pattern Recognition Receptors (PRRs) that recognise a broad range of molecules shared by pathogens - these are called Pathogen-Associated Molecular Patterns (PAMPs)
(Lecture 1, Slide 24)
What happens in inflammation after PAMPs are recognised by PRRs?
Inflammatory mediators are released by the cells
(Lecture 1, Slide 25)
What are the 2 types of inflammatory mediators released by cells?
Cytokines and chemokines
(Lecture 1, Slide 25)
What do cytokines mediate in inflammation and what do they cause?
They mediate the inflammatory response and cause fever
(Lecture 1, Slide 25)
What do chemical factors (such as histamine, serotonin, leukotrienes etc) cause in inflammation?
They cause vasodilation of blood cells
(Lecture 1, Slide 25)
What 2 things does vasodilation of blood cells in inflammation attract and what do these do?
Neutrophils to clear pathogens
Fluid containing beneficial proteins to the site of injury for healing purposes
(Lecture 1, Slide 25)
What do neutrophils summon in inflammation?
More leukocytes (white blood cells) including lymphocytes
(Lecture 1, Slide 25)
What do endothelial cells secret during inflammation?
Nitric oxide
(Lecture 1, Slide 26)
Is interferon a cytokine or chemokine?
Cytokine
(Lecture 1, Slide 28)
What does interferon do to a host cell?
It inhibits viral replication inside host cells
(Lecture 1, Slide 28)
Is interferon specific to a particular virus?
No
(Lecture 1, Slide 28)
What is the function of complement?
It can kill microbes without phagocytosis
(Lecture 1, Slide 28)
How does complement kill microbes without the use of phagocytosis?
It uses membrane attack complex (MAC) to create channels and burst the plasma membrane
(Lecture 1, Slide 28)
What do host cells produce if they end up getting infected by a pathogen?
“Distress” Ligands
(Lecture 1, Slide 30)
What recognises distress signals that are produced by host cells?
Natural Killer (NK) cells
(Lecture 1, Slide 30)
What do natural killer cells also have a part in detecting?
Cancer
(Lecture 1, Slide 30)
How is the innate immune system acquired?
It is inherited
(Lecture 2, Slide 3)
Is the innate system specific or non-specific?
Non-specific
(Lecture 2, Slide 3)
What are the motifs that damaged host cells express called?
Damage-Associated Molecular Patterns (DAMPs)
(Lecture 2, Slide 7)
What are 3 types of pattern recognition receptors?
Toll-like receptors (TLRs)
C-type lectin receptors (CLRs)
NOD-like receptors (NLRs)
(Lecture 2, Slide 8)
What type of receptors are TLRs?
Endosomal or plasma transmembrane receptors
(Lecture 2, Slide 9)
What 2 domains are TLRs composed of?
Leucine rich pathogen recognition domain and a signalling domain
(Lecture 2, Slide 9)
How many TLRs are there in the human body?
13
(Lecture 2, Slide 11)
What are cytokines?
Small hormone-like secreted proteins
(Lecture 2, Slide 13)
What are 5 things included in cytokines?
Chemokines
Interferons
Interleukins
Lymphokines
Tumour necrosis factors
(Lecture 2, Slide 13)
What do cytokines act through?
Cell surface receptors
(Lecture 2, Slide 13)
What do cytokines allow?
They allow communication between cells so that the right cells can be activated to destroy invading pathogens
(Lecture 2, Slide 14)