Immunology Intro Flashcards
1
Q
What are the 3 major parts of the immune system?
A
- physical + chemical barriers
- innate immunity
- adaptive immunity
2
Q
What are differences between innate and adaptive immunity?
A
- immediate response
- non-specific response
- retains no immunological memory
- natural immunity
- lag time between antigen exposure + response
- specific response
- retains immunological memory
- aquired immunity
3
Q
What are different types of innate immune cells?
A
- mast cell
- natural killer cell (large granular lymphocyte)
- blood
- basophil
- neutrophil
- esinophil
- monocyte
- tissues (phagocytes)
- mast cells
- macrophage
- dentritic cells
4
Q
How does the innate immune system recognise foreign bodies?
A
- phagocytes use Pathogen Recognition Receptors (PRR), to recognise Pathogen-Associated Molecular Patterns (PAMP)
- perform phagocytosis + oxidative killing
- activate transcription factors
- releasing proinflammatory cytokines
- phagocytes present digested antigens to addaptive immune system, using Major Histocompatability Complexes (MHC) in their surfaces
5
Q
What are Majoy Histocompatibility Complexes (MHC)?
A
- safety mechanism
- prevents immune system being activated to easily
- ensures T cells only react to antigen if presented with MHC complex
- “MHC restriction”
6
Q
What is an antigen and antibody?
A
- molecule capable of induing an immune response
- glycoprotein produced by B lymphocytes, that binds to anitgens, with high degree of specificity + affinity
7
Q
What are different types of adaptive immune cells?
A
Lymphocytes:
- B cells
- antigens
- T cells
8
Q
Where are lymphocytes matured?
A
- T cells
- bone marrow
- then thymus
- B cells
- bone marrow
- B + T cells then migrate to secondary lymphoid organs, where they encounter antigens
9
Q
How are lymphocytes specific to antigens?
A
- B cells + T cells have different types of receptors
- both types of receptors have variable regions
- genetic changes cause diverse antigen binding sites
10
Q
What is the key function of T helper (Th) cells?
A
- cytokine production
- large, heterogeneous soluble proteins
- act locally or at distance
- regulate + coordinate all cells of immune system- so regulate immune response
- produced during normal haematopoiesis
- produced in reponse to microbes, tissue damage, other antigens
- also produced by other cells, esp macrophages
- help B cell response
- to produce correct antibody isotype
- to improve antibody affinity
11
Q
What are features of NK cells?
A
- may respond to;
- their activating receptors to activating ligands on infected cells
- antibody-tagged cells
- directly to bacteria via TLR2
- can kill infected cells
- apoptosis
- produce IFN-g to stimulate; macrophages, TH1 cells, CD8+ cytotoxic cells
- important if T cell response is not optimal
12
Q
What are different immunoglobulin isotypes?
A
- all have different heavy chains- different functions
13
Q
How do antibodies affect the function of other immune cells?
A
- phagocyte
- neutralisation of microbes + toxins
- Fc receptor
- opsonisation + phagocytosis of microbes
- NK cell
- antibody-dependant cellular cytotoxicity
- complement activation
- lysis of microbes
- C3b receptor- phagocytosis of microbes opsonisation with complement fragments
- inflammation
14
Q
How does primary and secondary antigen exposure affect antibody mediated immunity response?
A
