1 - introduction Flashcards
immunology has been around for
500 million years
earliest signs of immunology seen in
sponges
purely phagcytotic
immunology seen in early sponges
purely phagocytotic phagocytic cells (primitive mobile cells) recognise foreign molecules to remove them
second organism in immunology evolution
lamprey
more complex
1st sign of lymphocytes and adaptive immune cells
3rd organsim in evolutionary immunology
bony fish
adaptive immunity
T and B lymphocytes
important receptors seen in fruit flies
Toll receptors -type of PRR
recognise conserved components of pathogens
differences between TLRs of fruit flies and humans
very similar
ours are more evolved
snails in immunology evolution
vectors of human parasites
recognise antigens on surface of parasites that infect them
important structure on snail
FRET
FRET
fibrogen-related loop 2 loops can be hyper-mutated primitive immunity
important proteins on primitive fish
proteins with similar components to antibodies
e.g. CDR3
chicken in evolution
compartmentalised lymphocyte differentiation
Ig gene conversion
name some immune structures
GALT
thymus
spleen
dendritic cells
GALT
gut associated lymphoid tissue
part of MALT
protects body against invasion from gut
why is 70% of immune system dedicated to the gut
food has potential to be very damaging
constantly ingesting potentially pathogenic and toxic substances e.g. spicy curry
body needs to differentiate normal food from pathogenic organisms
primary lymphoid organs
thymus
spleen
thymus
gland located in neck above the heart
nursery for immune cell maturity
generates mature T lymphocytes
spleen
acts as a filter
volume of blood passed through and toxins removed
storage of WBC
dendritic cells
enables relaying of information from innate to adaptive immunity
migrate from site of infection into lymphatic system to activate lymphocytes
number of cells in immune system
10^12
number of different cell types in immune system
10
number of cell-cell connections in immune system
infinite
haematopoeitic stem cells
pluripotent
found in bone marrow
form immune cells
immunity in leukemia
completely wiped out
requires bone marrow transplants
3 lineages from haematopoeitc stem call
lymphoid
myeloid
erythroid
immune memory in primitive fish and sharks
not good
cytokines are secreted by cells in
peripheral tissues
macrophages sit
underneath skin
surveillance
engage with infectious agents of cut
signals sent by macrophages
chemical signals (cytokines) - interleukins, tumour necrosis factor
M-CSF
example of cytokines signal from macrophages that would recruit more macrophages to differentiate from HSC
(macrophage - colony stimulating factor)
lymphoid lineage cells
NK cell
B cell
T cell
dendritic
myeloid lineage cells
macrophage neutrophil eosinophil basophil mast cell
examples of granulocyte cells
neutrophil
eosinophil
basophil
erythroid lineage cells
erythrocyte
mega karyocyte
components of plasma
95% water and dissolved proteins gluocse clottting factors electrolytes hormones CO2 O2
serum =
plasma without clotting factors
no RBC or WBC
what is serum used for
similar to interstitial fluid
in body - maintains osmotic pressure
in hospitals - used to look for antibodies
WBC leave capillaries in tissues and enter
lymphatics
where does blood plasma circulate
interstitial spaces
lymphatic system
the network of vessels through which lymph drains from the tissues into the blood.
the extent to which the two arms of immunity are activated depends on …
… the severity, context and duration of the disease
effect of cytokines on blood vessels
vasodilation
increased permeability
importance of cytokinesincreasing permeability of blood vessels
tight junctions loosen
inflammatory mediators can migrate into tissues
increased redness, heat, swelling
