Immune System Flashcards
What does Treg (CD25+, CD4+ T, FoxP3+ cell) secrete?
Secrete IL-10 and TGF-beta which will suppress auto reactive T cells and th1 cells.
Macrophages can secrete which 3 cytokines
IL-6, IL-1 and TNF-a
What’s the major group of WBCs in our body?
Neutrophils, aka polys
Mast cells and basophils are both involved in allergic responses. Where are they found?
Mast cells are found in connective tissues throughout the body. Basophils are found in blood.
Natural killer cells are large granular lymphocytes and can kill
Virus-infected cells and some tumor cells
In general, innate immune cells have receptors that can recognize microbial products. For example, dendritic cells and macrophages have what receptors to recognize LPS, a thymus independent antigen, on gram negative bacteria?
Toll-like receptor (TLR), specifically TLR-4
What are 3 main points of adaptive immunity?
- Requires sensitization by antigen
- Response is antigen specific
- Results in immunologic memory
Which two Ig classes can form polymeric immunoglobulins?
Pentameric IgM (monomeric IgM cannot produce antibodies) and dimeric IgA (both dimeric and monomeric IgA can make antibodies)
Adjuvant
added to vaccine to make it more immunogenic (aluminum salt alum)
passive immunity
use immune serum (Ab) to give an immediate resistance to an infection
active immunity
use of antigens to induce immune response to a pathogen
live attenuated
a weakened virus that can replicate to a limited extent
herd immunity (coccon effect)
when enough ppl are immunized such that spread of an infection is slow or halted.
What was the old vaccine that was given to protect against diptheria, pertussis, and tetanus. Why was it replaced?
The old vaccine called DPT was changed because it used the whole, killed pertussis which was too great of an adjuvant and caused swelling and fever.
How is the current diptheria, pertussis and tetanus vaccine different from the old?
DTaP vaccine uses acellular components of pertussis instead of the whole, killed pertussis. It is a pertussis toxoid with added aluminum salt as an adjuvant.
What is the booster given to protect against diptheria, pertussis and tetanus
Tdap =”d” and “p” are lower case because they are in reduced concentrations in the booster form. There are also just boosts for diptheria and tetanus (Dt or Td).
Polio vaccine aka IPV (inactivated polio vaccine) has done a great job at almost eradicating polio. Some vaccines were contaminated with?
Simian40 virus known to be a cancer-causing virus.
Why is the MMR (measles, mumps, and rubella) given at 12-15 months and not right at birth?
MMR is a live attenuated virus that requires the infant’s immune system to fight it to gain immunological memory. Up until 1 y.o, the infant has maternal antibodies that will fight off the MMR vaccine and not allow the infant’s own immune system to do so.
How will mothers with rubella impact their unborn children?
Rubella may be the leading cause of birth defects. Congential rubella syndrome is very serious.
Vaccine no longer has this product that anti-vaccine ppl used to say was a cause of autism
thimersol (mercury)
Cervarix protects against which strains of HPV?
HPV types 16 & 18
Gardasil protects against which strains of HPV
HPV types 16, 18, 6, and 11
Rabies is a deadly viral disease. What happens when someone without previous exposure is exposed to rabies? What’s the plan of treatment?
Give antiserum near wound and vaccine at a different site. The vaccine requires follow up doses on day 3, 7, and 14
Rabies is a deadly viral disease. What happens when someone with previous exposure is exposed to rabies again? What’s the plan of treatment?
Give booster
The rabies vaccine used to be a purified chick embryo cell vaccine, but now it is
human diploid cell rabies vaccine (HDCV)
Il-12 secreted by macrophages activate…
NK cells
Il-1 which is secreted by macrophages can increase vascular permeability by activating vascular endothelium and increase access of effector cells. Which cytokine is produced by Il-1?
Il-6 causing fever and induces acute phase protein
When macrophages sense microbial products, they secrete
Il-6, TNF-a, Il-1, CXCL 8, Il-12
Superantigen toxins (i.e. staph) cause symptoms similar to Gram negative sepsis because both will cause release of which cytokines
high fever, DIC due to release of TNF-a and IL-1
Tregs play a role in controlling which 5 diseases:
- colitis
- diabetes
- SLE
- graft rejection
- graft vs host
What factors dictate if Ag will favor immune response or tolerance?
- chemical nature of Ag (more complex Ag will favor immune response while less complex/soluble/aggregate free Ag will favor tolerance)
- amt of Ag (there’s an optimal dose; too large or too small a dose will favor immune tolerance)
- route of entry (subcutaneous and intramuscular injections favor immune response while oral and IV favor immune tolerance)
- genetics (some vaccines are more effective in one group than others)
- age of person; older ppl will be more likely to mount a response than young children who favor immune tolerance
- immune status of host
T/F: Most bacteria will die inside a phagocyte
True (it’s taffet’s rule #1); neutrophils and macrophages have lots of receptors for different bacteria.
What is the primary adaptive response to extracellular bacteria?
Antibody!
- prevents bacterial attachment to epithelium (IgA)
- Ab can trigger complement
- bind to M proteins or capsules (acting as opsonin)
- neutralize toxins
- neutralize spreading factors
Role of activated macrophages in dealing with intracellular bacteria
Activated macrophages (with TH1 Cell help) are non-specific but can kill better and can kill intracellular bacteria (listeria), but only active for a short period of time.
In most cases, which immune cell plays the major role against viruses and parasites?
T cell mediated immunity (but other cells play a role too)
