The red and white blood cells of a woolly mammoth that died in eastern Siberia 44.000 years ago have been found to be intact, the oldest body cells ever found in their original state.
"We were surprised there was anything there at all after such a long time," said Dr. Marion Barnhart, professor of psysiology at the Wayne State University School of Medicine in Detroit, which obtained tissue samples of the mammoth from the Soviet Academy of Sciences. "These are the oldest intact animal blood cells ever identified."
Though long dead, the intact red and white blood cells strongly suggest that the relatively new technique of freezing human body tissue and blood fractions can be improved upon in the laboratory. The discovery also promises to provide new clues to understanding the forces that disintegrate blood cells. t
The intact red and white blood cells came from a small slice of abdominal muscle taken from a whooly mammoth calf unearthed three years ago by Soviet scientists near Magadan in Siberia. The mammoth was declared by the Soviet Academy of Sciences to be the best preserved of any found in Siberia.
"I think there was a huge element of chance here," said Dr. Morris Goodman, professor of anatomy at Wayne State who together with Barnhart acquired the sample of abdominal tissue from the Soviet academy. "It's amazing that these cells were spared from rupture."
Goodman explained that under uncontrolled conditions like those found in the Siberian permafrost, most body cells long ago would have been destroyed by scavengers bacteria or the constant process of thaw and refreezing that might tear the cells apart.
"This is why we asked the Soviet academy for abdominal muscle tissue," Goodman said."The deep interior location of the muscle might have led to a slower rate of freezing and thawing that kept the tissue intact." h
Barnhart said the intact red and white blood cells were circulating blood cells that came from blood vessels taken from the mammoth's abdominal muscle. She said the red and white cells looked "physiologically normal" and similar to the blood cells of elephants to which the long-extinct mammoth was related.
So well preserved were the mammoth's white cells that they still had the tiny and delicate fingerlike projections biologists call "velli," which help to aid the white cells of mammals fight infection and resist disease.
"It's quite a surprise to find the white cells so intact," said Barnhart, who presented her findings recently at a meeting of the Electron Microscopy Society in Chicago. "To have identifiable tissue after 40,000 years is incredible."
Like the mastodon, the woolly mammoth was hunted into extinction by man about 10,000 years ago. Fossil evidence suggest that the mammoth, the mastodon and the elephant descended from the same prehistoric creature, then split into the different species about five million years ago.