Flashcards in Respiratory Immunology Deck (99)
what are 2 cytokines which induce an anti-viral state?
IFNa and IFNb
Name some pro-inflammatory mediators (produced by activated macrophages, mast cells, neutrophils)
Which mediator induces the production of ROS/ RNS by macrophages? Secreted by what?
IFNg (which is secreted by activated NK cells and effector Th1 cells)
Which mediator, secreted by Th cells, promotes proliferation and differentiation of activated CD4+ and CD8+ cells?
Which cytokines are secreted by Th1 cells? What do they do?
IFNg, IL-2, TNFa: increases proliferation and activity of macrophages, NK and CD8+ cells , increased proliferation of B cells and production of opsonising Ig (IgG, IgM and IgA), IL-2 and IFNg positively feedback for Th1 production, IFNg inhibits Th2 production.
(for clearance of bacteria, viruses, fungi (intracellular!), promotes inflammation, autoimmune disease, lots of IFNg = fibrosis)
Which cytokine, secreted by Th0 cells, stimulates differentiation into Th1?
Name an anti-inflammatory cytokine
IL-10 (secreted by macrophages once the pathogen has been eliminated)
Which cytokine, secreted by Th0 cells, stimulates differentiation into Th2?
Which cytokines are secreted by Th2 cells? What do they do?
IL-4, IL-5, IL-10, IL-13
IL-10 is anti-inflammatory
IL-4 positively feedbacks for Th2 cell production, and increases proliferation and activation of eosinophils and mast cells
IL-5 increases proliferation of B cells and class switching to IgE
IL-13 is for airway hyperresponsiveness and mucus hypersecretion
Functions: clearance of parasites (helminths), suppression of inflammation, and allergy and asthma
Which cytokines, secreted by Th0 cells, stimulate differentiation in Th17?
IL-6 and TGFB
Which cytokines does Th17 secrete? What are their functions?
IL-17 and IL-22
IL-17 affects epithelium, causing increased recruitment of neutrophils
Il-22 increases cytokine and chemokine production by many cells
Function: clearance of bacteria and fungi (extracellular), promotes inflammation, autoimmune diseases, increased neutrophil infiltration in severe asthma
Which cytokine, secreted by Th0, stimulates differentiation into Treg (T regulatory cell)?
Which cytokines does T-reg secrete? What are the functions?
Decreases the function of macrophages and APCs
Decreases secretion of pro-inflammatory cytokines
Overall: function is suppression of immune response, and protection against autoimmunity
development of active immunity through exposure to a less virulent pathogen
these are for bacteria which secrete toxins
The toxins are detoxified with formalin and so are safe for use in a vaccine. When the immune system receives a vaccine containing a harmless toxoid, it develops active immunity against the natural toxin.
e.g. vaccines against tetanus and diphtheria
what are the 3 types of inactive vaccine?
features of attenutated (killed) vaccines?
-not as effective as live vaccines
-may need boosters
-immune response is primarily antibody based (not T cells)
what type of vaccine is the salk polio vaccine?
administered by injection
needs 3 doses
more expensive than salk
things added to vaccine to modify the immune response by boosting it, such as to give a higher amount of antibodies and a longer-lasting protection, thus minimising the amount of injected material
benefits of inactivated vaccines?
-usually safe (CAN be given to IC individuals)
-no refrigeration required
-can be made quickly
disadvantages of inactivated vaccines?
-difficult to stimulate an immune response to many killed organisms
-poor at eliciting T cell responses
-memory is variable so boosters needed
examples of whole cell inactivated vaccines?
polio (salk, inactivated), Hep A, rabies, cholera ,plague
examples of fractional (subunit) inactivated vaccines?
hep B, influenza, acellular pertussis, HPV, anthrax
examples of toxoid inactivated vaccines?
these include only the antigens that best stimulate immune system (e.g. just epitopes sometimes)
chances of adverse reactions are low
bacteria may have polysaccharide sugars on outer capsule, but these generate antibodies with less functional activity - especially in immature immune system
Immunogenicity can be improved by conjugating with an adjuvant (making it into a conjugate vaccine)
Conjugate vaccines convert polysaccharide antigens to protein to ensure there is a B AND T cell response
examples of polysaccharide only vaccine?
examples of polysaccharide conjugated to toxin vaccine?
-Haemophilus influenza type B vaccine
live attenuated vaccines
these contain a weakened version of the living microbe - so can't cause disease. These elicit strong response and give lifelong immunity with just one or two doses. IC people cannot have live attenuated vaccines because there's a chance it could cause disease