Retroviral Disease

Question 1

Define ‘retrovirus’.

Answer 1

A single stranded RNA virus which replicates inside the host cell using a viral enzyme to produce its own DNA.

Question 2

What type of transcription does the enzyme undergo?

Answer 2

Reverse transcription

Question 3

What factors increase the risk of contracting HIV?

Answer 3

Violence
Poverty
Low level of education
Drug use
Substance abuse
Binge drinking
Condom choice
Police harassment

Question 4

What is the subtype of HIV in SA?

Answer 4

HIV1-Group M-Subtype C

Question 5

Routes of infection/transmission

Answer 5

Sexual contact (semen, vaginal secretions)
Blood (whole blood, plasma, clotting factors, cellular fractions of blood)
Contaminated needles
Perinatal (transplacental, during delivery, breast milk)

Question 6

What is tropism?

Answer 6

A preference for a particular cell type that preferentially will infect

Question 7

What are the two tropic strains?

Answer 7

T-tropic

M-tropic

Question 8

Discuss the T-tropic strain

Answer 8

Infects CD4 and T lymphocytes

Uses CXCR4 co-receptors to infect cells

Question 9

Discuss the M-tropic strain

Answer 9

Infects macrophages and microglia

Uses CCR5 co-receptors to infect cells

Question 10

Define the innate immune response

Answer 10

Activation of the adaptive response through antigen presentation

Question 11

Define adaptive immune response

Answer 11

The humeral response and antibody production. The cell-mediated response–helper T-cell differentiation

Question 12

Effectors in innate immune response

Answer 12

Phagocytes
Inflammatory mediators
Complement
Natural killer cells

Question 13

Effectors of the adaptive immune response

Answer 13

B-cells (antibodies)

T-cells