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Which cells are tissue resident sentinel cells - ✔✔mast cell, macrophage, dendritic cell
Which 2 cells are circulating blood cells that will enter tissue in response to inflammation? -
✔✔Neutrophils, Monocytes
Mast cell - ✔✔Cells that release chemicals (such as histamine) that promote inflammation.
Neutrophil - ✔✔Most abundant leukocyte, increase due to bacterial infection, burns, and stress.
Phagocyte that rapidly dies after ingesting microbe.
Macrophages - ✔✔Phagocyte that cleans up apoptotic cells.
When a monocyte moves into the tissues, it changes rapidly and becomes a _____________ -
✔✔macrophage
Leukocyte adhesion deficiency (LAD) is a genetic defect that leads to recurrent infections in the tissue
and severe problems with wound healing. LAD patients also develop severe gingivitis (infections and
inflammation of the gums). In LAD, leukocyte migration into tissues is severely impaired. All of these
problems can be traced back to a genetic defect. Of the genetic defects listed below, which is the most
likely cause of LAD? - ✔✔A mutation that introduces a stop codon into a gene that encodes part of the
LFA-1 molecule (leading to a truncated protein).
Toll-like receptors for bacterial PAMPs are found on/in the_________________ - ✔✔cell membrane
There are a few different proteins that act as inhibitors of NF-kB. There is a very rare genetic disease in
which one of these proteins, IkBa, is mutated. The mutation substantially alters the stability of the IkBa
protein. In patients with this disease, IkBa protein expression does not change in response to stimuli that
, cause IkBa degradation in healthy individuals. Consider the biological role of NF-kB inhibitors. What are
the most likely symptoms of this genetic defect? - ✔✔Immunodeficiency with a susceptibility to bacterial
infections.
The complement pathway initiated by host proteins that bind to microbial sugars is called the
______________________ pathway. - ✔✔lectin pathway
SSRNA (single-stranded RNA) and dsDNA (double-stranded DNA) are present in mammalian cells. Why
don't our plasmacytoid dendritic cells activate an innate immune response against these self nucleic
acids that are necessary for normal cellular function? - ✔✔The TLRs that recognize SSRNA and dsDNA
are sequestered in endosomes.
How can the antiviral state be propagated in the absence of immune cells? - ✔✔Type I IFs are produced
by infected epithelial cells; this induces antiviral biochemical changes in the same cell and adjacent cells.
A child presents with recurrent bacterial infections. Of the genetic defects described below, what is the
most likely cause of her disease? - ✔✔A mutation in the C3 gene that renders the C3 protein
nonfunctional.
It is the process by which something that is not otherwise recognized as a pathogen is coated with
proteins that make it more recognizable to the immune system - ✔✔Opsonization
The majority of the symptoms of tetanus infection are caused by the tetanus toxins, chiefly
tetanospasmin. Tetanospasmin is one of the deadliest toxins known; even very small doses (nanograms)
can be lethal. It targets the nerves, causing severe muscle spasms. The tetanus vaccine consists of
inactivated tetanus toxin; the vaccine is highly effective for preventing tetanus. Inoculation with the
tetanus vaccine leads to the production of protective antibodies. How do these antibodies prevent
tetanus? - ✔✔Neutralization
Streptococcus pneumonia is an extracellular bacterium that is a leading cause of bacterial pneumonia
and meningitis, particularly in children and the elderly. Fortunately, most cases of S. pneumonia can be
prevented with a vaccine that contains components of the bacterial capsule. The vaccine is known to
lead to the production of antibodies that recognize intact bacteria. What are the most likely mechanisms
activated by these antibodies that result in protection against S. pneumoniaeinfection? (select two
Answers) - ✔✔The key is that S. pneumonia is an extracellular bacterium. The vaccine elicits a humoral
immune response, which generates antibodies that bind to the surface of the bacterium. The antibodies