week 6: lymphoid & immune systems Flashcards
what do adaptive defences have?
immunological memory
what are the 2 main immune defences?
innate
adaptive
what does a cellular & humoral immune response begin with?
activation of a helper T cell (Th)
are adaptive defences specific or non-specific?
specific
what are 3 examples of cytokines?
interferons
IL-1
IL-2
what are the 4 defensive mechanisms used by antibodies called?
neutralisation
agglutination
precipitation
complement protein activation
what happens in secondary lymphoid organs & tissues?
foreign materials become trapped & destroyed
or
immune response generated
what do granzymes do?
induce apoptosis
what are 2 accessory structures of the physical barrier?
hairs (skin & nose)
cilia of the mucociliary escalator
when does an autoimmune disease occur?
when the body’s immune defences target normal tissues
what are 3 examples of pyrogens?
IL-1
interferons
bacterial toxins
where does B cell maturation occur?
bone marrow
what do NK cells destroy?
virus-infected cells
cancerous cells
what are 4 examples of secondary lymphoid organs & tissues?
lymph nodes
spleen
appendix
tonsils
what is the treatment for anaphylactic shock?
adrenaline (epinephrine)
what does increased capillary permeability allow?
clotting factors, macrophages, neutrophils & complement proteins to enter damaged tissue
where are lymph nodes located?
along lymphatic vessels
what do interferons inhibit?
viral replication
what do secondary lymphoid organs & tissues contain?
WBCs
how many L of ISF enters the lymphatic capillaries to form lymph per day?
3
are innate defences present at birth?
yes
how can mild or moderate fevers be beneficial?
inhibit growth of some bacteria & viruses
increases cell metabolism - accelerates immune defences
by taking up space how does normal flora prevent pathogen colonisation?
pathogens unable to attach to body cells/tissues
what are cytokines & what do they do?
chemical messengers
recruit &/or activate WBCs
what are the 3 functions of lymph?
regulates ISF volume
maintains BV & BP
transports WBC & foreign materials to lymph nodes
what is complement activation (by antibodies)?
antibodies bind to antigen & activate complement proteins
what are 3 possible causes of lymphoedema?
tumours
surgery
parasitic infections
what does increased blood flow (by dilated arterioles) bring to the damaged area?
complement proteins
clotting factors
macrophages & neutrophils
what do perforins do?
create pores in the target cell membrane, allowing entry of granzymes
what does the lymphoid system protect the body from?
foreign materials & internal threats
adaptive defences are systemic, what does this mean?
not restricted to initial infection site
what are the 2 types of surface barriers?
physical
chemical
what is a systemic response to an allergen called?
anaphylactic shock
what does a primary immune response produce?
memory T & B cells
what produces interferons?
WBCs
virus-infected cells
what is a humoral immune response mediated by?
B cells
what is an antigen called in hypersensitivity?
allergen
what is the role of the cilia of the mucociliary escalator?
move foreign materials from the respiratory tract towards the throat
what does the humoral response produce during a secondary immune response?
large amounts of IgG
what do damaged cells release?
histamine & prostaglandins (inflammatory chemicals)
how does normal flora prevent pathogen colonisation?
consuming essential nutrients
taking up space
what 3 cells are involved in autoimmune diseases?
self-reactive cytotoxic T cells
self-reactive B cells
regulatory T cells
what are 2 examples of primary lymphoid organs?
red bone marrow
thymus
what is lymph?
excess ISF
white-milky protein containing fluid
what is immunocompetence?
the ability to recognise & bind 1 specific antigen
what is a primary immune response?
first time an antigen invades the body
what are 3 examples of cellular antigens?
cancerous cells
foreign cells
virus/bacteria/parasite infected cells
what does lymphoedema increase the risk of & why?
infection
pathogens can accumulate w/in body tissues
what 3 things does the release of histamine & prostaglandins cause?
dilation of arterioles
capillaries become leaky
attract macrophages & neutrophils
what does HIV stand for & what does it primarily infect & destroy?
human immunodeficiency virus
helper T cells
what do lymphatic capillaries contain?
flaplike minivalves
are adaptive defences present at birth?
no - acquired/develop throughout life
what are the 4 components of the lymphoid system?
lymphatic system
lymphoid organs & tissues
WBC
cytokines
what is this WBC?
neutrophil
what is a primary immune response & does it protect the body from illness?
small, slow, short-lived
no
what do pyrogens result in?
fever
what are cytokines produced & secreted by?
WBCs
what is this WBC?
eosinophil
what is neutralisation?
antibodies bind to specific sites on antigens to block their attachment to body cells
what is self-tolerance?
the ability to recognise “self-antigens” from “non-self-antigens”