Overview Of The Immune System Flashcards
What are type of pathogens?
Bacteria
Protozoa
Viruses
Fungi
Virus
Parasite
Protein
What is an antigen?
Any substance capable of triggering an immune response
Non-self protein on pathogen
What are the characteristic shapes of individual antigens called?
Epitopes
=protrudes from its surface
Are some epitopes more effective than others are stimulating immune response?
Yes
What are the physical barriers?
Skin
Reproductory
Respiratory tracts
Digestive tracts
What systems does the mucous membrane line?
Digestive
Reproductory
Respiratory
What is the role of the mucous membrane?
Prevent attachment of many pathogens
Sticky, traps pathogens and shed off
What does the mucous contain?
Antimicrobial enzymes
Enzyme inhibitors
Lysis
immunoglobulins
Why do we not attack self-antigens?
Self-tolerance
Describe innate immune system?
Non-specific
First to come into play
Will produce the same response time and again - no memory
This is the immunity when you are born
Describe the adaptive immune system?
Highly specific
Immunological memory
Antibody production
When does the innate response kick in?
Hours
When does the adaptive immune response kick in?
Days
What are the cells of the immune system?
Phagocytic cells
Cells releasing inflammatory mediators
NKC
Molecules
What are phagocytic cells?
Leukocytes …Neutrophils Eosinophils
Monocytes
Macrophages
What are the leukocytes?
Neutrophils
Eosinophils
Monocytes
Where are macrophages?
In tissue
What cells release inflammatory mediators?
In tissue= Macrophages And Mast cells
Leukocytes (basophils and eosinophils)
What are non-specific humoral factors?
Soluble substances = growth inhibitors, enzyme inhibitors, lysins
Where are the non-specific humoral factors?
Body fluids (and mucous)
What is the role of growth inhibitors?
Deprive micro-organisms of nutrients essential for their growth
Interfere with metabolism
Include transferin and interferon
Temperature dependent
What is transferrin and interferon?
Transferin (bacteriacidal activity - binds iron)
Interferon (antiviral activity)
What can activate the complement system?
Classical
Alternative
Lectin
What is the role of complement?
Edibles the gap between adaptive and innate immunity
What is the end result of the complement pathway?
MAC montane attack complex
Opsonisation
How many proteins are involved in the complement system?
Over 20
What is an example of a lysin?
Lysozyme
What does lysozyme act upon?
Peptidoglycans (protein and carbohydrate)
What does MAC do?
Create a pore on the pathogen membrane
What cell does opsonisation attract?
Macrophages
What protein is key in the CS?
C3
What 2 smaller fragments does C3 get clipped to?
C3a C3b
What is smaller and what is larger, C3a or C3b?
C3a is smaller
C3b is larger
What does the a,ternative pathway form?
C5 convertase
What is involved in the classical pathway?
C1 binding to Ab
What CS is shown?
Classical pathway
How does the lectin pathway work?
Pathogens have lectin on surface (host cells do not)
MBL cells bind and activate complement
What is the central event in complement activation?
Proteolysis of complement protein C3
When is MAC fully activated?
When final protein C9 is bound
What can chemktractans contribute to?
Anaphylactic shock
What are the functions of complement?
