1. In medical biotechnology, scientists often use markers
(fluorescent labels, the green fluorescent protein GFP, ...) in their
in vitro or in vivo experiments. Technically, it is possible to add
such markers (e.g. the cDNA code of GFP) to your therapeutic
constructs. Mention a number of advantages and disadvantages of
the use of GFP for human applications.
Advantages of using GFP to human applications is that GFP is easily
detected and its fluorescence is very stable.
Disadvantages are that GFP is a foreign protein and this could trigger an
immune response in humans. Over time it could loose its fluorescence
Advantages: It is relatively less invasive and you can easily detect it. You
can trace therapeutic proteins non-invasively
Disadvantage: it takes up place in your vector and you could use the space
for different gene. You can influence the activity of the gene and protein
folding/ activity by adding something additional that is not there, such as
GFP. Since GFP is big it might influence the function or activity of the
protein of interest. Putting GFP to your protein of interest creates an
Fushion protein and this could influence expression. By adding an IRES of
two promotors you can make sure that two separate proteins are formed
so you still have the protein of interest and GFP.
2. During the lecture, there were five classes of viruses mentioned,
retroviruses,
lentiviruses, HSV, adeno-associated viruses and adenoviruses. Consider
the following cell types: hematopoietic stem cells, liver cells, retinal
photoreceptor cells. Which of these viruses would you use for the different
target cells and why?
hematopoietic stem cells
These are fastly dividing cells and you want to use lentiviruses or a
retrovirus because they both integrate into the genome. When you have
genome integration and subsequent cell division and transfer then you will
have long term stable gene expression.
liver cells
There are mononuclear cells and binuclear cells and mononuclear cells are
able to divide and binuclear cells don’t have a true division but the two
nuclei in the cell are being split up. It depends on which cell you want the
target. Dividing cells you take lentivirus or retrovirus and for the binuclear
cells you take AAVs.
retinal photoreceptor cells
Adeno-associated viruses (AAVs) are the most suitable for retinal cells,
particularly because of their ability to target non-dividing cells.
(fluorescent labels, the green fluorescent protein GFP, ...) in their
in vitro or in vivo experiments. Technically, it is possible to add
such markers (e.g. the cDNA code of GFP) to your therapeutic
constructs. Mention a number of advantages and disadvantages of
the use of GFP for human applications.
Advantages of using GFP to human applications is that GFP is easily
detected and its fluorescence is very stable.
Disadvantages are that GFP is a foreign protein and this could trigger an
immune response in humans. Over time it could loose its fluorescence
Advantages: It is relatively less invasive and you can easily detect it. You
can trace therapeutic proteins non-invasively
Disadvantage: it takes up place in your vector and you could use the space
for different gene. You can influence the activity of the gene and protein
folding/ activity by adding something additional that is not there, such as
GFP. Since GFP is big it might influence the function or activity of the
protein of interest. Putting GFP to your protein of interest creates an
Fushion protein and this could influence expression. By adding an IRES of
two promotors you can make sure that two separate proteins are formed
so you still have the protein of interest and GFP.
2. During the lecture, there were five classes of viruses mentioned,
retroviruses,
lentiviruses, HSV, adeno-associated viruses and adenoviruses. Consider
the following cell types: hematopoietic stem cells, liver cells, retinal
photoreceptor cells. Which of these viruses would you use for the different
target cells and why?
hematopoietic stem cells
These are fastly dividing cells and you want to use lentiviruses or a
retrovirus because they both integrate into the genome. When you have
genome integration and subsequent cell division and transfer then you will
have long term stable gene expression.
liver cells
There are mononuclear cells and binuclear cells and mononuclear cells are
able to divide and binuclear cells don’t have a true division but the two
nuclei in the cell are being split up. It depends on which cell you want the
target. Dividing cells you take lentivirus or retrovirus and for the binuclear
cells you take AAVs.
retinal photoreceptor cells
Adeno-associated viruses (AAVs) are the most suitable for retinal cells,
particularly because of their ability to target non-dividing cells.