Immunology 4 - HIV infection Flashcards
Using which enzyme does HIV replicate inside cells?
Reverse Transcriptase
How many genes are inside the HIV genome?
9
What is the role of reverse transcriptase in HIV?
Converts RNA into DNA which can be incorporated into host cells’ genes
What are the two key glycoproteins encoded by the HIV virus?
gp120
gp41
Which cell of the immune system is particularly affected by HIV?
CD4+ T cells
Recall the receptor and co-receptors for HIV on CD4+ T cells
CD4 receptors
CCR5 CXCR4 coreceptors
In people who have natural immunity to HIV, what antibodies may be present in serum?
Anti-gp120 and anti-gp41 (Nt) antibodies
How does HIV infection affect CD8+ T cells?
Interferes with activation, as CD4+ T cell and antigen-presenting cell help are not present due to the virus
How does HIV infection affect monocytes and dendritic cells?
Not activated by CD4+ T cells and so cannot prime naive CD8+ T cells
How does HIV affect immunological memory?
CD4+ T cell memory is lost
CD8 memory cell not activated by antigen-presenting cell
Why is there so much variation/mutation in HIV infection?
HIV lacks same checking mechanisms in DNA transcription
Why is HIV mutation within the host problematic?
Escape from neutralising antibodies.
Escape from HIV-1-specific T cells.
Resistance and escape from antiretroviral drugs.
Recall the 7 steps of the HIV life cycle
- Attachment/Entry
- Reverse Transcription and DNA Synthesis
- Integration
- Viral Transcription
- Viral Protein Synthesis
- Assembly of Virus and Release of Virus
- Maturation
Which drugs are capable of inhibiting the action of reverse transcriptase in HIV infection?
- Nucleoside analogues
2. Non-nucleotide reverse transcriptases
Which class of HIV drugs can prevent integration of viral DNA?
Integrase inhibitors