A team of physicians and laboratory scientists
has taken a key step toward a cure for sickle
cell disease, using CRISPR-Cas9 gene editing
to fix the mutated gene responsible for the
disease in stem cells from the blood of affected
patients.
For the first time, they have corrected the
mutation in a proportion of stem cells that
is high enough to produce a substantial benefit
in sickle cell patients
In tests in mice, the genetically engineered
stem cells stuck around for at least four
months after transplantation, an important
benchmark to ensure that any potential therapy
would be lasting.
A crucial question is whether or not this
gene editing treatment is lasting.
We edit the cells today.
Will the edited cells be around to keep you
healthy years from now, potentially?
So, to test that, we edited human cells in
the laboratory.
We then injected them into mice.
And then we looked at the editing of the cells
four months later and asked whether or not
the edited cells hung around.
When we do that we find that about 2% of the
stem cells that remain in the bone marrow
after four months are edited.
Which in the case of sickle cell disease,
is, um, that level of editing is likely to
have clinical benefit, but we would like to
get a little bit better than 2% in the future.
As for the excitement about the future of
this technique, I'm extremely excited because,
you know, we haven't been trying this for
very long.
You know, we will get better.
And what we have right now is already, you
know, if we can scale it up and make sure
that it works well, is already good enough
to form the basis of a clinical trial to cure
sickle cell disease with gene editing.
