Written
by CBC News Online staff BLACKSBURG,
VIRGINIA - Scientists have dried out human kidney cells and revived them eight
days later. The technique could have all sorts of medical applications.
Blood
for transfusions could be stored for long periods, for example, or carried to
remote disasters without having to be kept cool. Antibodies and vaccines would
have an almost unlimited shelf life, making them easier to distribute in developing
countries.
The technique copies the way some bacteria can cope without
water. Cells usually die within seconds without water. But a photosynthethic bacteria
called Nostoc commune has evolved the ability the survive for centuries without
water.
The photosynthetic bacteria live on exposed rock surfaces, where
they often dry out. When water splashes onto the rocks, the bacteria come back
to life. The cells swell up, forming what's known as "star jelly" and "witches'
butter."
Scientists at the Virginia Tech Center for Genomics say the bacteria
survive by covering themselves with a slimy layer called glycan.
"It forms
a wooly overcoat for the cells," said Malcolm Potts, who adapted the technique
for kidney cells. "By applying the technique we have found in cyanobacteria, we
can dry out human cells."
Just add water
In the experiment,
glycan was mixed with human kidney cells.
The cells were then dried out,
and eight days later, they were rehydrated.
Half of the cells started
to divide again.
Scientists have dried and revived human cells before.
The first time happened at the University of California, San Diego, where
scientists dried out cells for five days and then rehydrated them.
The
San Diego researchers genetically modified the cells to make a sugar called trehalose,
which protects cells from freezing and drying from the inside.
But other
researchers have failed to repeat their results.
The new study is reported
in the April 21 issue of New Scientist magazine. |
