Exam material
Lectures
e-learning modules
Reader
Practicals
Immunology
L1 & 2: innate immune processes
History immune system
o Concept of protected immunity
o Plague: survivors less likely to contract in again
o China: 1st clear reference to smallpox
- Powdered smallpox blown up in nose of healthy -> mild case
o Western world: 2 reports of inoculation, vaccination
o Fast development
- Textbook reflects what we know now
Objectives
➢ Understand main functions immune systems
➢ Define innate immune process involved in responses towards bacteria & viruses
Overview immune system
Self & non-self
• Main function immune system
1. Protection against infectious microbes/ non-self
2. Protection against modified self (cancer)
• self => body’s own cells
non-self => foreign cells (antigen)
• Distinction made via peptide presentation in MHC
- Body cells carry self marker molecule
,Primary lymphoid organs => bone marrow and thymus
• Production & selection immune cells
• Bone marrow
- Source of all blood cells
- B cells (humoral response)
• Thymus
- T cells (cellular response)
Secondary Lymphoid organs => lymph nodes, spleen,
MALT
• Drain certain parts of body + ensure cells of
innate & adaptive immune system meet &
screen antigens, immune cells ‘’wait’’ here
• Lymph nodes
- Clustered in neck, armpits abdomen &
groin
- Contains all immune cells; mostly
lymphocytes, few granulocytes (prevent
inflammation)
• Spleen
- Like lymph nodes: all immune cells, but
mostly lymphocytes
- Macrophages in marginal zone
- T cells in PALS (= peri-arteriolar
lymphatic sheaths)
- B follicles adjacent to PALS; germinal centre contains memory B cells & plasma cells
• MALT -> mucosal associated lymphoid tissue (tonsils, adenoids, appendix)
- Contain mature B & T cells
Symptoms of infection -> caused by immune response rather than by invaders
- Goblet cells produce mucus, other epithelial cells produce AMPs (antimicrobial peptides)
- Epithelial cells recognize pathogens by TLRs (toll like receptors)
o Invasion by pathogen:
1. Recognition of PAMP (pattern associated molecule) by TLR -> intracellular signalling cascade
2. Transcription of alarm molecules (cytokines/chemokines) -> alert immune cells underneath
epithelial layer
o Damage to epithelial layer
- Activation of acute phase proteins (= APP)
- APPs produced by hepatocytes (just like complement factors)
- Examples: fibrinogen, haptoglobin, mannan-binding lectin, serum amyloid A (= SAA), C-
reactive protein (= CRP)
,Leukocytes (white blood cells) = immune cells
o Underneath epithelial cells -> patrol surface
o Innate immunity: fast & no memory for specific pathogen (there is training)
o Adaptive immunity: slower but specific (not always alarmed)
Mononuclear cells
• Monocytes (blood) -> macrophage (tissue) (innate)
• Lymphocytes (adaptive)
• NK cells (innate)
Granular cells (innate)
• Neutrophils
• Eosinophils
• Basophils
• Mast cell
, Monocytes
• Effector functions:
1. Killing microbes
2. Inflammation (enhances adaptive immunity)
3. Tissue remodelling
• Products: ROI (reactive O intermediates), NO, fibroblast growth factors, angiogenic factors,
metalloproteinases, pro-inflammatory cytokines, increased MHC molecules, co-stimulators
Lymphocytes
• T -> Th, CTL/Tcyt, Treg
• B -> plasma cell producing antibodies (immunoglobulin)
NK cells -> destroy bacteria, parasites, virus-infected cells & some cancer cells
• Extravasation from blood to tissue induced by chemokines
• Functions
1. Produce cytokines that help defence
2. Help kill infected cells by forcing apoptosis
• Receptors: activating (kill) & inhibitory (do not kill)
Phagocytes
• Macrophages & dendritic cells (DC), neutrophils
• Function steps:
1. Extravasation => recruitment of cells to site of
infection
2. PRR (= pattern recognition receptors) =>
recognition of & activation by microbes
3. Phagocytosis => ingestion of microbe
4. Antigen presentation on MHC & secretion of
cytokines => destruction & communication to
adaptive immune system
Immunoglobulins (=antibodies; adaptive)
• Produced by activated B cell (plasma cell)
• 2 heavy chains + 2 light chains
• Great variability at tip of Y arms (Fab fragment), rest is constant
- Fab => antigen binding site
- Tail => Fc site
Lectures
e-learning modules
Reader
Practicals
Immunology
L1 & 2: innate immune processes
History immune system
o Concept of protected immunity
o Plague: survivors less likely to contract in again
o China: 1st clear reference to smallpox
- Powdered smallpox blown up in nose of healthy -> mild case
o Western world: 2 reports of inoculation, vaccination
o Fast development
- Textbook reflects what we know now
Objectives
➢ Understand main functions immune systems
➢ Define innate immune process involved in responses towards bacteria & viruses
Overview immune system
Self & non-self
• Main function immune system
1. Protection against infectious microbes/ non-self
2. Protection against modified self (cancer)
• self => body’s own cells
non-self => foreign cells (antigen)
• Distinction made via peptide presentation in MHC
- Body cells carry self marker molecule
,Primary lymphoid organs => bone marrow and thymus
• Production & selection immune cells
• Bone marrow
- Source of all blood cells
- B cells (humoral response)
• Thymus
- T cells (cellular response)
Secondary Lymphoid organs => lymph nodes, spleen,
MALT
• Drain certain parts of body + ensure cells of
innate & adaptive immune system meet &
screen antigens, immune cells ‘’wait’’ here
• Lymph nodes
- Clustered in neck, armpits abdomen &
groin
- Contains all immune cells; mostly
lymphocytes, few granulocytes (prevent
inflammation)
• Spleen
- Like lymph nodes: all immune cells, but
mostly lymphocytes
- Macrophages in marginal zone
- T cells in PALS (= peri-arteriolar
lymphatic sheaths)
- B follicles adjacent to PALS; germinal centre contains memory B cells & plasma cells
• MALT -> mucosal associated lymphoid tissue (tonsils, adenoids, appendix)
- Contain mature B & T cells
Symptoms of infection -> caused by immune response rather than by invaders
- Goblet cells produce mucus, other epithelial cells produce AMPs (antimicrobial peptides)
- Epithelial cells recognize pathogens by TLRs (toll like receptors)
o Invasion by pathogen:
1. Recognition of PAMP (pattern associated molecule) by TLR -> intracellular signalling cascade
2. Transcription of alarm molecules (cytokines/chemokines) -> alert immune cells underneath
epithelial layer
o Damage to epithelial layer
- Activation of acute phase proteins (= APP)
- APPs produced by hepatocytes (just like complement factors)
- Examples: fibrinogen, haptoglobin, mannan-binding lectin, serum amyloid A (= SAA), C-
reactive protein (= CRP)
,Leukocytes (white blood cells) = immune cells
o Underneath epithelial cells -> patrol surface
o Innate immunity: fast & no memory for specific pathogen (there is training)
o Adaptive immunity: slower but specific (not always alarmed)
Mononuclear cells
• Monocytes (blood) -> macrophage (tissue) (innate)
• Lymphocytes (adaptive)
• NK cells (innate)
Granular cells (innate)
• Neutrophils
• Eosinophils
• Basophils
• Mast cell
, Monocytes
• Effector functions:
1. Killing microbes
2. Inflammation (enhances adaptive immunity)
3. Tissue remodelling
• Products: ROI (reactive O intermediates), NO, fibroblast growth factors, angiogenic factors,
metalloproteinases, pro-inflammatory cytokines, increased MHC molecules, co-stimulators
Lymphocytes
• T -> Th, CTL/Tcyt, Treg
• B -> plasma cell producing antibodies (immunoglobulin)
NK cells -> destroy bacteria, parasites, virus-infected cells & some cancer cells
• Extravasation from blood to tissue induced by chemokines
• Functions
1. Produce cytokines that help defence
2. Help kill infected cells by forcing apoptosis
• Receptors: activating (kill) & inhibitory (do not kill)
Phagocytes
• Macrophages & dendritic cells (DC), neutrophils
• Function steps:
1. Extravasation => recruitment of cells to site of
infection
2. PRR (= pattern recognition receptors) =>
recognition of & activation by microbes
3. Phagocytosis => ingestion of microbe
4. Antigen presentation on MHC & secretion of
cytokines => destruction & communication to
adaptive immune system
Immunoglobulins (=antibodies; adaptive)
• Produced by activated B cell (plasma cell)
• 2 heavy chains + 2 light chains
• Great variability at tip of Y arms (Fab fragment), rest is constant
- Fab => antigen binding site
- Tail => Fc site
