HIV & AIDS: Pathogenesis and Treatment

Question 1

HIV causes infection by binding to what structures on lymphocytes? What HIV glycoprotein do they use to bind?

Answer 1

HIV gp 120 binds to CD4 and CCR5

Question 2

Briefly describe the HIV replication cycle

Answer 2

1. HIV gp 120 binds to CD4/CCR5
2. Is endocytosed into the cell
3. Genomic RNA becomes unintegrated DNA via RT
4. Integrase integrates DNA into host cell DNA
5. This is then transcripted into mRNA or genomic RNA
6. mRNA synthesises viral proteins
7. Genomic RNA buds off and forms a HIV virion

Question 3

Having a CD4 count below what has an increased risk of serious opportunistic infections?

Answer 3

< 200 cells / micro litre

Question 4

State 4 complications of HIV infection

Answer 4

• Kaposi’s sarcoma
• Pneumocystis pneumonia
• CNS toxoplasmosis
• CMV retinitis

Question 5

State the 6 classes of anti-retroviral drugs used to treat HIV

Answer 5

NRTIs
NNRTIs
Protease Inhibitor
Boosting agent
CCR5 inhibitor
Integrase Inhibitor