Scientists plan to create human stem cells from cows

The procedure would involve taking a human body cell (never to be a person) and inserting it into an enucleated cow ovum (never to be human). The resulting mass of cells would end up as a thin layer in a petri dish, never to be human, but posessing the genetic apparatus of a human (just a a skin cell does). It would enable scientists to create human stem cells without asking for excess embryos from fertility clinics, which could then continue on their accustomed path (either file and forget or dry out and dump).

Cells from patients would create cloned stem cell lines that contain the same genetic mutation that results in these neurological disorders.

“We feel that the development of disease-specific human embryonic stem cell lines from individuals suffering from genetic forms of neurodegenerative disorders will stimulate both basic research and the development of new treatments for devastating brain diseases,” Dr. Stephen Minger, of the stem cell biology laboratory at King’s College London, said Monday in a release.

And it would never have been a baby.

Transplants of immature retinal cells restore sight to mice

English and American scientists worked with 10 mice that had lost their photoreceptors. The cells are destroyed in eye diseases such as macular degeneration and retinitis pigmentosa.

“This research is the first to show that photoreceptor transplantation is feasible,” said Dr. Robert MacLaren, a clinician scientist and eye surgeon from Moorfields Eye Hospital in London.

Previous attempts at transplanting stem cells into the retina of adult mammals haven’t worked because the transplanted cells did not wire up to the brain properly.

In the experiment reported in Thursday’s issue of the journal Nature, MacLaren and his colleagues used immature retinal cells from newborn mice, which were transplanted into the retinas of adult mice.

* Survived.
* Correctly developed into rod photoreceptors.
* Connected to the neurons in sufficient numbers to carry visual signals to the brain.
* Allowed mice with an inherited form of retinal degeneration to respond to light.

For this to work, the scientists needed to use cells from a specific time during development when the cells stopped developing. The “precursor” cells were programmed to become photoreceptors but had not yet started to function.

“Perhaps within the next five years, we will begin to see the first steps toward retinal cell transplants for people with blinding eye disease,” said study co-author Anand Swaroop, a professor of ophthalmology at the University of Michigan Medical School.

Stinging hot

The venom of a West Indian tarantula and the “hot” in chili peppers affect the same nerve cells.
Tarantula venom targets the heat sensor on nerve cells known as the capsaicin receptor,
When the researchers tested venoms from 22 spider and scorpion species, the venom from the tarantula Psalmopoeus cambridgei activated the capsaicin receptor (Nov. 9 issue of Nature).

The research shows that some plants and animals have the same molecular strategy to deter predators, senior author David Julius, professor and chair of physiology at the University of California, San Francisco, said Wednesday. “These toxins give us clues as to how specific activators or blockers on these channels can be designed to treat persistent pain, from arthritis, bladder infections or other diseases.”

Tangled Bank #66 on Eastern Blot

Tangled Bank is a collection of online science articles, published twice a month. Eva at Eastern Blot presents Tangled Bank 66, “The Future, the Present, and the Past.”

Tags: science, evolution, Tangled Bank, science writing, medical writing, natural history, organisms, Eastern Blot