Deeltoets 1
1.3 Barriere defenses against infection
The skin is the first barrier against infection. It is an epithelium protected by a tough, impenetrable
layer of keratinized cells. Tissues of the respiratory, gastrointestinal and urogenital tracts are coated
with mucus. This layer contains glycoproteins, proteoglycans and enzymes that protect the epothlial
cells. Epithelial surfaces also secrete antimicrobial substances, such as peptides that kill bacteria,
fungi and viruses.
1.4 Innate immune response
When a pathogen enters the body the innate immune response will react. This consists of two
phases: recognition of the pathogen by proteins and cell-surface receptors and kill or eliminate the
pathogen by effector cells. The effector cells are activated by pathogens with molecular flags. The
innate immune response contains of numerous families of receptor proteins that recognize a
pathogen.
1.5 The adpative immune response
When a infection outruns the innate immune response the adaptive immune respone is activated.
Lymphocytes recognize pathogens using one type of cell-surface receptor. Lymphocyte receptors are
encoded by genes that are cut, spliced and modified during development. During infection only
lympfocyted specific for the pathogen are recruited, then they proliferate en differentiatie > many
pathogen-specific effector cells = clonal expansion. Memory cells elicit a stronger and faster adaptive
immune respons.
1.6 The immune-system cells
Hematopoietic cells: leukocytes, erythrocytes (red blood cells), megakaryocytes, platelets and their
precursors. Daughter cells can differentiate to become more mature stem cells, through trhee
lineagers: erythroid, myeloid annd lymphoid.
- myeloid precusor cell: gives rise to myeloid cells such as granulocytes, neutrophils, eosinophils and
basophils. These cells have granules filled with reactive biochemicals that kill microorganisms and
enhance inflammation. Neutrofils are the most abundant en live short > pus
- Monocytes are leukocytes that circulate in the blood. Monocytes differetiate into macrophages by
the infected tissue.
- Natural killer cells are small granular lymphocytes that respond to viral infection.
1.7 Immunoglobulins and T-cell receptors
- Immunoglobulins are the cell-surface of the B-cell receptors. A soluble form of the B-cell is secreted
by plasma cells > antibody > interfere with pathogen growth and replication > limit infection =
neutralization. This is called humoral immunity.
1.11 Lymfoid tissues
Primary lymphoid tissue: where lympfocytes develop and mature, bone marrow and thymus
Secondary lymphoid tissue: where mature lyphocytes encouter pathogen-derived antigens and are
activated > effector cells.
Lymph flow is one direction. One-way valves and lymph nodes ensure that the movent is in direction
away from peripheral tissue and toward the ducts in the upper body where is empties into blood.
Pathogens and antigen-laden dendritic cells enter the lymphe node in an afferent lymphatic vessel.
, 2.3 complement system
First reaction when a pathogen enters the tissue. Coats the surface of the pathogen > more
susceptible to phagocytosis Complement is activated by a cascade of enzym reactions. Most
components are proteases.
Complement C3: most important > small C3a and big C3b fragment > C3b bind to the pathogen > tag
for phagocytosis. C3a is a chemoattractant. C3a can be activated by three pathways: zie HC.
2.6 Macrophages
Opsonization: coating of C3b to the pathogen improves the effciency of phagocytosis of the
marcophage.
2.7 Membrane-attack complex (MAC)
A large pore that is assembled in the membrane of bacterial and eukaryotic pathogens and kills them
by pertubing their structural integrity. Complemnet cascade from C5, C6, C7, C8 and C9 proteins.
3.1 The receptor of the innate immunity
The cells of the immuun system are able to distiguish healthy cells (self), microbes (non-self) and
infected cell (altered-self). The receptor recognizes a structural feature which is shared by a family of
related pathogens.
Macrophages have a variety of cell-surface receptors. The capture pathogens> intracellular
endosomes > lysosome kills the pathogen
3.7 Cells infected with a virus
Alle nucleated human cells can detec viral nucleic acids and induce the production of interferons.
Interferons interfere with viral replication and instruct nearby uninfected cells > effects NK cells
3.12 Inflammation
Neutrophils are granulocytes that cicrulated in the blood and have numerous cytoplasmic granules.
Neutrophils are short lived. They have a range of phagocytic receptors that recognize microbial
products > phagocytosis.
Aantekeningen hoorcollege
Aangeboren immuunsysteem: reageert heel snel en aspecifiek. Tweede afweerlinie.
- Epitheel barrière: slijm in het maagdarmstelsel
- Neutrofielen, macrofagen: produceren cytokines > dilatatie capillairen > epitheelcellen gaan lek >
1.3 Barriere defenses against infection
The skin is the first barrier against infection. It is an epithelium protected by a tough, impenetrable
layer of keratinized cells. Tissues of the respiratory, gastrointestinal and urogenital tracts are coated
with mucus. This layer contains glycoproteins, proteoglycans and enzymes that protect the epothlial
cells. Epithelial surfaces also secrete antimicrobial substances, such as peptides that kill bacteria,
fungi and viruses.
1.4 Innate immune response
When a pathogen enters the body the innate immune response will react. This consists of two
phases: recognition of the pathogen by proteins and cell-surface receptors and kill or eliminate the
pathogen by effector cells. The effector cells are activated by pathogens with molecular flags. The
innate immune response contains of numerous families of receptor proteins that recognize a
pathogen.
1.5 The adpative immune response
When a infection outruns the innate immune response the adaptive immune respone is activated.
Lymphocytes recognize pathogens using one type of cell-surface receptor. Lymphocyte receptors are
encoded by genes that are cut, spliced and modified during development. During infection only
lympfocyted specific for the pathogen are recruited, then they proliferate en differentiatie > many
pathogen-specific effector cells = clonal expansion. Memory cells elicit a stronger and faster adaptive
immune respons.
1.6 The immune-system cells
Hematopoietic cells: leukocytes, erythrocytes (red blood cells), megakaryocytes, platelets and their
precursors. Daughter cells can differentiate to become more mature stem cells, through trhee
lineagers: erythroid, myeloid annd lymphoid.
- myeloid precusor cell: gives rise to myeloid cells such as granulocytes, neutrophils, eosinophils and
basophils. These cells have granules filled with reactive biochemicals that kill microorganisms and
enhance inflammation. Neutrofils are the most abundant en live short > pus
- Monocytes are leukocytes that circulate in the blood. Monocytes differetiate into macrophages by
the infected tissue.
- Natural killer cells are small granular lymphocytes that respond to viral infection.
1.7 Immunoglobulins and T-cell receptors
- Immunoglobulins are the cell-surface of the B-cell receptors. A soluble form of the B-cell is secreted
by plasma cells > antibody > interfere with pathogen growth and replication > limit infection =
neutralization. This is called humoral immunity.
1.11 Lymfoid tissues
Primary lymphoid tissue: where lympfocytes develop and mature, bone marrow and thymus
Secondary lymphoid tissue: where mature lyphocytes encouter pathogen-derived antigens and are
activated > effector cells.
Lymph flow is one direction. One-way valves and lymph nodes ensure that the movent is in direction
away from peripheral tissue and toward the ducts in the upper body where is empties into blood.
Pathogens and antigen-laden dendritic cells enter the lymphe node in an afferent lymphatic vessel.
, 2.3 complement system
First reaction when a pathogen enters the tissue. Coats the surface of the pathogen > more
susceptible to phagocytosis Complement is activated by a cascade of enzym reactions. Most
components are proteases.
Complement C3: most important > small C3a and big C3b fragment > C3b bind to the pathogen > tag
for phagocytosis. C3a is a chemoattractant. C3a can be activated by three pathways: zie HC.
2.6 Macrophages
Opsonization: coating of C3b to the pathogen improves the effciency of phagocytosis of the
marcophage.
2.7 Membrane-attack complex (MAC)
A large pore that is assembled in the membrane of bacterial and eukaryotic pathogens and kills them
by pertubing their structural integrity. Complemnet cascade from C5, C6, C7, C8 and C9 proteins.
3.1 The receptor of the innate immunity
The cells of the immuun system are able to distiguish healthy cells (self), microbes (non-self) and
infected cell (altered-self). The receptor recognizes a structural feature which is shared by a family of
related pathogens.
Macrophages have a variety of cell-surface receptors. The capture pathogens> intracellular
endosomes > lysosome kills the pathogen
3.7 Cells infected with a virus
Alle nucleated human cells can detec viral nucleic acids and induce the production of interferons.
Interferons interfere with viral replication and instruct nearby uninfected cells > effects NK cells
3.12 Inflammation
Neutrophils are granulocytes that cicrulated in the blood and have numerous cytoplasmic granules.
Neutrophils are short lived. They have a range of phagocytic receptors that recognize microbial
products > phagocytosis.
Aantekeningen hoorcollege
Aangeboren immuunsysteem: reageert heel snel en aspecifiek. Tweede afweerlinie.
- Epitheel barrière: slijm in het maagdarmstelsel
- Neutrofielen, macrofagen: produceren cytokines > dilatatie capillairen > epitheelcellen gaan lek >
