Chapter 6: T Cells and Immunity Flashcards
Why do newborns have less immune defense?
1) Immature immune system
2) Low NK function (permits them to be colonized by good bacteria)
How are newborns protected from their low immune systems?
Receive Abs from mom’s breastmilk
Proteins released by host cells in response to viral infection that inhibit viral multiplication, stimulate resistance in adjacent uninfected cells, and stimulate the immune system.
Interferons
Why do bats not suffer ill effects of the many deadly viruses they carry?
Because they have IFNs (interferons) switched on all the time.
What types of pathogens are interferons and NKCs most effective against?
Viruses
What types of pathogens is complement effective against?
Bacterial pathogens
In what way are MHC/HLA markers inherited?
As a haplotype (1/2 from mom, 1/2 from dad)
True or false: MHC/HLA types must be matched as closely as possible for successful transplants.
True
Where is MHC II located? What response does it generate?
Only on immune-related cells; alerts and stimulates the immune response.
Where is MHC I located? What response does it generate?
On all nucleated cells to signify that they are the body’s own and, if infected by some pathogen, need to be destroyed.
What does porforin do? What releases it?
Punches holes in cell membranes to cause apoptosis; cytotoxic T cells (CD8+)
Which is the only MHC/HLA to encode class II molecules?
HLA-D
