Wk 9- Adaptive Immune System Flashcards
The Adaptive immune system is:
The - line of defence
Is s? in action, not localised
Has a - and reacts forcefully against a - infection
3rd
Systemic
Memory, 2nd
Adaptive immunity and Antigens:
Foreign cells have - on their surface.
These - are recognised by cells of the adaptive immune system = - induce an adaptive immune response > the production of anti?
Our bodies possess their own self anti- (A,B,Rh)
Most antigens are p? or polysaccharides.
Antigens Antigens Antigens , antibodies Antigens proteins
Divisions of the adaptive immunity:
A.I can be divided into 2 groups
- Cell Me? immunity and
- H? immunity (fluid)
Cell mediated
Humoral
Divisions A.I
- Cell mediated
Immune function performed by activated ?
Destroys intracellular pa? cancerous cells and fo? cells.
Cells
Pathogens foreign
Divisions A.I
- Humoral immunity
Antibody mediated immunity = i? function performed by -
Removes extra cellular pa?
Immune
Antibodies
Pathogens
Lymphocytes:
Humans carry around 1? weighing 1 -- What are the 3 classes of lymphocytes? 1. -- cells 2. - cells: 3 types= cytotoxic (CD8) and helper ?cells (CD4) memory (thymus) 3. - cells (bone marrow)
Trillion, kg
- NK , natural killer
- T cells
- B cells
T and B cell receptors:
Each individual T or B cells produces receptors for only - antigen
T cells have additional receptors which are proteins. C?? C??
B = 1 antigen
T = 1 antigen ,2 proteins
1
CD4 , CD8
Our cells display their own self antigens.
Human self antigens = MHC molecules
What does MHC stand for?
Major his? Com?
MHC can be divided into class 1 and class 2
Major historycompatability complex
MHC classes: 1 endogenous antigens
Class 1
N? cells
Incorporate foreign anti? after infection
Labels cell as infected to cytotoxic ? cell (CD?)
Nucleated
Antigen
T, CD8
MHC classes: 2 exogenous antigens
Class 2
Displayed by antigen p- cells (APC)
Engulf and break down pathogenic antigen (Mac? Den? cells and ? Cells)
Present antigen MHC complex to Helper ? cells (CD?)
Presenting
Macrophages, dendritic cells, B cells
T, CD4
Memory T cells:
Produced during ? cell activation~ cloned
Remain in l? tissue
Very fast reaction to second exposure of infection/ a?
T cell
Lymphatic
Antigens
B cell activation:
Antigen binding Activation via ? T cells Division and differentiation Produce ~ 1. Pl? cells (antibodies) 2. M? cells
Helper
Plasma Cells
Memory cells
B cell activation:
- Plasma cells
Secrete antibodies 2000/second/cell
Short lifespan last 4-? Days
Peak plasma antibody concentration at -0 days - Memory B cells
Remember ? for fast future activation
4-5
10
Antigens
Antibodies:
Immunoglobulins (Igs)
Y shaped
Target extra cellular pathogens and t?
5 mechanisms
Agglutination ~ antibodies clump antigens together to enhance pha?
Opsonisation~ immunoglobulin coats anti? and binds phagocytes enhancing pha?
Neutralisation~ antibodies bind pathogenic components of t? and block toxic effects
Complement activation~ antibodies activate complement pr? leading to cell lysis
Inflammation ~ immunoglobulin binds ma? cells and basophils triggers release of ? response
Toxins Phagocytosis Antigens , phagocytosis Toxins Proteins Mast cells Inflammatory