Stem Cells May Save Northern White Rhinos - Rawan For Media Artistic and Production
At
a meeting in Vienna from Dec. 3 to Dec. 6, researchers developed a plan
to use stem cells to create fertilized rhino embryos, which will be
carried by surrogate southern white rhino females.
This
past year has been a sad one for northern white rhinos, a rapidly
disappearing subspecies destroyed by habitat loss and poaching. There
were six northern whites on the planet, all in captivity, in December
2014. That month, the second-to-last male, Angalifu, died at the San
Diego Zoo. That left Sudan, a 42-year-old rhino at the Ol Pejeta
Conservancy in Kenya, as the only northern white male rhino on Earth.
Next
to go was 31-year-old Nabire, a female who died of a ruptured cyst at
the Dvir Kralove Zoo in the Czech Republic in July. An infection claimed
Nola, a 41-year-old female at the San Diego Zoo, in November.
Now
the only three remaining northern whites live at the Ol Pejeta reserve.
Sudan still survives, but is too old to mount a female. And the two
remaining females, Najin and Fatu, also have health problems that
prevent them from reproducing the old-fashioned way.
So
scientists plan to collect egg and sperm cells from the last living
northern whites and combine them with induced pluripotent stem cells(iPS
cells). These are cells taken from the rhino's body and chemically
induced to turn back the clock to an earlier developmental phase, when
cells are capable of becoming many different types of body tissue. The
hope is that scientists can reverse-engineer body cells into sperm and
egg cells. Fertilized embryos could then be made by in vitro
fertilization (IVF) and transferred into southern white rhinoceroses,
the northern white's nearest relative.
But
there are complications to this plan: No one has ever successfully
completed IVF on a rhino of any species. Every species requires its own
cell-culture conditions to mimic the unique environment of the uterus,
Barbara Durrant, director of reproductive physiology at the San Diego
Zoo Institute for Conservation Research, told Live Science in June.
Depending on how long it takes to make the breakthroughs necessary to
create rhino embryos in a lab, the species could go extinct before
scientists successfully breed new individuals.
One
of the researchers at the Vienna meeting was Katsuhiko Hayashi, a
scientist at Kyushu University, who successfully bred mice from eggs
created from mouse skin cells in 2012. Researchers are now working to
transfer this technology from mice to northern whites, according to a
statement from the Dvir Kralove Zoo. The Czech zoo is working with San
Diego Zoo Global, Tiergarten Sch?nbrunn in Austria and the Leibniz
Institute for Zoo and Wildlife Research in Berlin to lead the project. A
white paper on the group's progress is expected next year.
By LIVESCIENCE, 16 hours 34 minutes ago
With
only three northern white rhinoceroses left on Earth, conservationists
are giving up on traditional breeding efforts and turning to
cutting-edge science to save this subspecies.
only three northern white rhinoceroses left on Earth, conservationists
are giving up on traditional breeding efforts and turning to
cutting-edge science to save this subspecies.
At
a meeting in Vienna from Dec. 3 to Dec. 6, researchers developed a plan
to use stem cells to create fertilized rhino embryos, which will be
carried by surrogate southern white rhino females.
This
past year has been a sad one for northern white rhinos, a rapidly
disappearing subspecies destroyed by habitat loss and poaching. There
were six northern whites on the planet, all in captivity, in December
2014. That month, the second-to-last male, Angalifu, died at the San
Diego Zoo. That left Sudan, a 42-year-old rhino at the Ol Pejeta
Conservancy in Kenya, as the only northern white male rhino on Earth.
Next
to go was 31-year-old Nabire, a female who died of a ruptured cyst at
the Dvir Kralove Zoo in the Czech Republic in July. An infection claimed
Nola, a 41-year-old female at the San Diego Zoo, in November.
Now
the only three remaining northern whites live at the Ol Pejeta reserve.
Sudan still survives, but is too old to mount a female. And the two
remaining females, Najin and Fatu, also have health problems that
prevent them from reproducing the old-fashioned way.
So
scientists plan to collect egg and sperm cells from the last living
northern whites and combine them with induced pluripotent stem cells(iPS
cells). These are cells taken from the rhino's body and chemically
induced to turn back the clock to an earlier developmental phase, when
cells are capable of becoming many different types of body tissue. The
hope is that scientists can reverse-engineer body cells into sperm and
egg cells. Fertilized embryos could then be made by in vitro
fertilization (IVF) and transferred into southern white rhinoceroses,
the northern white's nearest relative.
But
there are complications to this plan: No one has ever successfully
completed IVF on a rhino of any species. Every species requires its own
cell-culture conditions to mimic the unique environment of the uterus,
Barbara Durrant, director of reproductive physiology at the San Diego
Zoo Institute for Conservation Research, told Live Science in June.
Depending on how long it takes to make the breakthroughs necessary to
create rhino embryos in a lab, the species could go extinct before
scientists successfully breed new individuals.
One
of the researchers at the Vienna meeting was Katsuhiko Hayashi, a
scientist at Kyushu University, who successfully bred mice from eggs
created from mouse skin cells in 2012. Researchers are now working to
transfer this technology from mice to northern whites, according to a
statement from the Dvir Kralove Zoo. The Czech zoo is working with San
Diego Zoo Global, Tiergarten Sch?nbrunn in Austria and the Leibniz
Institute for Zoo and Wildlife Research in Berlin to lead the project. A
white paper on the group's progress is expected next year.
By LIVESCIENCE, 16 hours 34 minutes ago
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