Diagnostic Virology Flashcards
Within the HTLV-1 virus particle, in which form is the genetic material?
ssDNA
What type of cell does HTLV-1 preferentially infect?
T cells
How does HTLV-1 replicate?
HTLV-1 can integrate within the chromosome of infected cells and replicate as dsDNA as part of the host cell division process
What are 3 possible routes to become infected with HTLV-1 ?
Blood transfusion
From mother to infant by breast feeding
Sexual Contact
What diseases can be caused by HTLV-1?
HTLV-1-associated myelopathy
Leukaemia
What are PCR methods used o detect HTLV-1 based on?
The presence of the tax gene
What are the three steps of the western blot method
- Separation
- Transfer
- Staining
What does the western blot method look for?
Presence of antibodies specific to the virus
Describe the separation stage of the western blot procedure?
Viral proteins separated based on size on plyacrylamide protein gel
Which proteins will migrate fastest on the polyacrylamide gel of the western blot?
The smaller proteins
What happens to the western blot after the viral proteins are separated by size and have formed bands?
Incubated with human serum - if the human serum contains antibodies it will bind to the viral proteins
What happens in the staining phase of the western blot method?
Secondary antibodies which have an enzyme attached are added - they bind to the Fc region of the already bound antibodies
Then substrate is added which reacts with the enzyme to produce a signal
What must be detected for a positive result for HTLV-1?
MTA1 p53 p24 p19 gd21
What are the five components of PCR based analysis?
- Buffer
- Nucleotides - dNTPs
- DNA POlymerases
- Primers
- DNA Template
What is the purpose of the buffer in PCR?
Provides an appropriate pH for reactions to occur / polymerase to work
What are the three steps of PCR?
- Denature
- Anneal
- Elongate
What temperature does denaturation occur at?
90 degrees - breaks H bonds between double-stranded DNA