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Flashcards in Viruses as therapeutics Deck (18):
1

what vectors are most commonly used in gene therapy clinical trials (virus vectors)

adenovirus
retrovirus

2

retrovirus vectors contain

LTRs (for integration)
psi sequence (packaging)
exogenous genes that replace viral genes

3

retrovirus vector is like a normal infec in the recipient except up until what point?

stops after integration. does not create packaged virions

4

advantages of retrovirus vectors

control of host range, cell and tissue tropism (change the envelope proteins to target specific cells)

5

disadvantages of retrovirus vectors

random integration in host chromosomes
mutagenesis upon insertion (LTR contains enhancers for transcription in T cells)
maintaining high levels of gene expression
depends on target cell prolif with MMLV-based vector

6

lentivirus vectors (retrovirus) enter what cells

non dividing

7

difference btwn adnovirus and retrovirus vectors

adenovirus vector DNA does NOT integrate into host genome

8

problems with the adenovirus vector

short term gene expr, as vector is not integrated into host genome

immune response

size restrictions on inserted genes

how to get around:
make gutless vectors that prevent immune response

9

what family is vaccinia virus in

poxvirus

10

what is good about vaccinia virus?

large genome so can have flexibility with size of DNA packaged

11

where does replication of vaccinia virus occur?

cytoplasm

12

where does the foregin gene get inserted to in the vaccinia genome for the vaccinia vector

non-essential site

13

recombination of genes for the vaccinia virus involves

recombining gene of the virus with gene from the vector

14

which of the viral vectors are replication incompetent?

retrovirus
adenovirus

15

which viral vector is replication competent

poxvirus (vaccinia0 vectors)

16

what is a notable wild virus that is oncolytic?

reovirus

17

what are some genetically manipulated viruses designed to kill cancer cells?

adenoviruses
herpes simplex viruses
vaccinia

18

how is conditionally replicative adnovirus able to target cancer cells

deletion of its E1A or E1B gene regions

incorporate tumor specific promoters

change virus cell attachment protein