Immuno 8: HIV Infection Flashcards
Which cells does HIV mainly infect ?
CD4+ T helper cells
Name 2 co-receptors of T cells that HIV-1 needs to bind to in order to cause infection ?
CCR5 or CXCR4
List 3 routes of transmission of HIV ?
Sexual- especially anal sex
Infected blood- Needle sharing, transfusions, blood products
Vertical transmission- Mother to child during birth or breast feeding
At which 2 parts of HIVs lifecycle do mutations occur that create variation in its genome ?
1- When reverse transcriptase converts viral RNA into DNA
2- When viral DNA is transcribed in the host’s nucleus into viral RNA
List 4 possible mechanisms that can could cause long term non-progression in HIV infected patients ?
CCR5 mutation
Effective CTL & HTL response
Infection with attenuated strain of HIV
Secretion of chemokines that block HIV entry into cells - MIP-1a
Which tests are done for HIV screening, diagnosis, severity ?
HIV antibodies on ELISA (screening test)
HIV antibodies on Western blot (Confirms diagnosis)
Viral RNA on PCR (viral load)
CD4+ count on flow cytometry
Why does HAART not eliminate HIV infection ?
There is a reservoir of HIV in resting CD4+ cells
List 3 classes of anti retroviral drugs and an example of a drug in each ?
Nucleoside reverse transcriptase inhibitors (NRTI)- Zidovudine
Nucleotide RTI- Tenofovir
Non-NRTI- efavirenz
Protease inhibitor- ritonavir