assessment 7 Flashcards
Dx that is a result of genetic deficiency of FoxP3 in Tregs autoimmunity :
IPEX
Type of virus – influenza?
Negative sense RNA virus
Antigenic shift causes huge change in this influenza protein:
hemagluttination
Insect born protozoa that replicate in EC tissue spaces:
trypanosomes
Trypanosomes coated with single type of glycoprotein:
VSG
Trypanosome evasion of host immune system?
Programmed re-arrangement of DNA: cassette system to express only 1 of 1000 different VSG (variant specific glycoprotein)
State in which no viral proteins produced (no disease caused, no CTL’s active) –
Latency
Herpes simplex virus occupies what cells?
Nerve
Why are neurons susceptible to viral infections?
Low # MHC I to decrease unnecessary killing by CTL’s
Mononucleosis is caused by?
Epstein-Barr Virus
Epstein-Barr infects what cells?
Causes them to proliferate until they are killed by CTL’s: B Cells
Pathogens most likely to subvert host defenses?
Viruses
Mycobacterium TB resistance to immune system?
Prevents fusions of lysosome and phagosome
Listeria evasion of immune system?
Escapes phagosome until macrophage killed by CTLs
Toxoplasma gondii evasion of the immune system?
Makes its own vesicles inside phagosome
What produces toxic shock syndrome toxin 1?
Staphylococcus
What does a super antigen bind?
Vb region of TCR and MHC II
Superantigen activates… % T cells?
2%-20%
Superantigen causes…
Massive release of cytokines
Phase of Ag specific Antibody present and detectable in the serum
Seroconversion
Lentivirus? Example?
slow, HIV
HIV: profound decrease in?
CD4 cells
HIV binds with high affinity to_____ and must interact with_____ to gain entry into the cell.
CD4 and chemokine receptor
Antigenic variation in HIV is due to _____?
Error prone reverse transcriptase
Asplenia increases susceptibility to?
Septic infections (encapsulated bacteria)
Neutropenia is a deficiency in _____? must be less than ____ cell/ul?
Granulocytes, <500 cells/ul