Immunology PPT
-Innate immune system = always present, responds rapidly, nonspecific, responds
generally to pathogenic threats
First line of defense
Physical barriers —> skin, mucous membranes, cilia protect as an outer
layer and inhibit pathogen movement
Chemical barriers —> pH changes in the GI tract and enzymes contained
in sweat, tears, sebaceous glands help wash pathogens away, inhibit their movement,
kill them
Genetic components —> some people have a mutation that keeps a viral
spike from binding to the host cell receptor (ie. Scandinavians and HIV resistance)
Second line of defense = immune cells that move around body and look for cell
surface markers to distinguish “self” from “non-self”
leukocytes (WBC) most abundant
Phagocytosis
Inflammation
Fever —> molecules called pyrogens induce a fever —> low
fevers helpful in fighting off pathogens by inhibiting their growth, increasing
effectiveness of cytokines, tissue repair
Antimicrobial proteins
Granulocytes
Neutrophils: most abundant, LOVE to eat bacteria through
phagocytosis, can also release toxins and enzymes to destroy foreign particles
Eosinophils: target large, multicellular eukaryotes, release
toxins to kill foreign cells, first to arrive at site of inflammation, regulates inflammation
Basophils/Mast cells: full of heparin (anticoagulant) and
histamines, stimulate inflammation, basophils located in blood, mast cells located in
tissues
Agranulocytes
Monocytes: largest of the WBC and main function is phagocytosis,
located in blood
Macrophages: monocytes that enter tissues
Dendritic cells: general phagocytes located on tissues with
external environmental contact, sheet like extensions, travel to lymph nodes once
they’ve eaten something
**monocytes, macrophages, dendritic cells secrete cytokines that
help communicate and organize the immune response**
Natural killer cells: immune surveillance —> wonders checking
that our cells are functioning normally and looking for pathogens
, if it detects an
abnormal cell, it induced apoptosis with granzymes
protects from pathogens and cancerous cells
Cytokines = communication molecules of the immune system (ie
interleukins)
interferons (INF) are a type of cytokine and signal used by
infected cells to let other surrounding cells know
Complement system = complements the innate and adaptive parts of the
immune system through three pathways
Classical pathway - complement binds to an antibody and its
antigen
Lectin pathway - complement binds to specific carbohydrates on
microbes
Alternative pathway - low level, spontaneous activation
Complement system leads to —> opsonization = complement
binds to foreign object and allows phagocytic cells to eat it
membrane attack complex =
pokes holes in cell membranes leading to cytolysis
immune complex = serves as a
transporter for antibodies attached to antigens leading it to a RBC where it can travel to
a macrophage
promotes inflammation =
interact with immune cells to promote inflammation
-Adaptive immune system = responds to specific threats, takes time to initially
develop but will respond quickly if exposed to same pathogen in the future (anamnestic
response —> immune memory)
Third line of defense = lymphocytes that have unique receptors to recognize
specific antigens (this means we have trillions of lymphocytes as an adult)
selective tests for working lymphocytes —> Positive
selection = cells have tools they need to do job
Negative selection
= make sure cells do not recognize self antigens (=> autoimmune diseases)
If cells do not pass,
they go through apoptosis
If they pass, they go
out to body through blood and lymphatic system looking for their antigens
Rely on two cell types:
-Innate immune system = always present, responds rapidly, nonspecific, responds
generally to pathogenic threats
First line of defense
Physical barriers —> skin, mucous membranes, cilia protect as an outer
layer and inhibit pathogen movement
Chemical barriers —> pH changes in the GI tract and enzymes contained
in sweat, tears, sebaceous glands help wash pathogens away, inhibit their movement,
kill them
Genetic components —> some people have a mutation that keeps a viral
spike from binding to the host cell receptor (ie. Scandinavians and HIV resistance)
Second line of defense = immune cells that move around body and look for cell
surface markers to distinguish “self” from “non-self”
leukocytes (WBC) most abundant
Phagocytosis
Inflammation
Fever —> molecules called pyrogens induce a fever —> low
fevers helpful in fighting off pathogens by inhibiting their growth, increasing
effectiveness of cytokines, tissue repair
Antimicrobial proteins
Granulocytes
Neutrophils: most abundant, LOVE to eat bacteria through
phagocytosis, can also release toxins and enzymes to destroy foreign particles
Eosinophils: target large, multicellular eukaryotes, release
toxins to kill foreign cells, first to arrive at site of inflammation, regulates inflammation
Basophils/Mast cells: full of heparin (anticoagulant) and
histamines, stimulate inflammation, basophils located in blood, mast cells located in
tissues
Agranulocytes
Monocytes: largest of the WBC and main function is phagocytosis,
located in blood
Macrophages: monocytes that enter tissues
Dendritic cells: general phagocytes located on tissues with
external environmental contact, sheet like extensions, travel to lymph nodes once
they’ve eaten something
**monocytes, macrophages, dendritic cells secrete cytokines that
help communicate and organize the immune response**
Natural killer cells: immune surveillance —> wonders checking
that our cells are functioning normally and looking for pathogens
, if it detects an
abnormal cell, it induced apoptosis with granzymes
protects from pathogens and cancerous cells
Cytokines = communication molecules of the immune system (ie
interleukins)
interferons (INF) are a type of cytokine and signal used by
infected cells to let other surrounding cells know
Complement system = complements the innate and adaptive parts of the
immune system through three pathways
Classical pathway - complement binds to an antibody and its
antigen
Lectin pathway - complement binds to specific carbohydrates on
microbes
Alternative pathway - low level, spontaneous activation
Complement system leads to —> opsonization = complement
binds to foreign object and allows phagocytic cells to eat it
membrane attack complex =
pokes holes in cell membranes leading to cytolysis
immune complex = serves as a
transporter for antibodies attached to antigens leading it to a RBC where it can travel to
a macrophage
promotes inflammation =
interact with immune cells to promote inflammation
-Adaptive immune system = responds to specific threats, takes time to initially
develop but will respond quickly if exposed to same pathogen in the future (anamnestic
response —> immune memory)
Third line of defense = lymphocytes that have unique receptors to recognize
specific antigens (this means we have trillions of lymphocytes as an adult)
selective tests for working lymphocytes —> Positive
selection = cells have tools they need to do job
Negative selection
= make sure cells do not recognize self antigens (=> autoimmune diseases)
If cells do not pass,
they go through apoptosis
If they pass, they go
out to body through blood and lymphatic system looking for their antigens
Rely on two cell types:
