The new finding, published in the Journal of the Royal Society Interface, is a first for Otzi's mummy, which has been under scientific scrutiny since a pair of hikers stumbled over the body frozen in ice on the Austrian-Italian border.
And the research could also help confirm the story of the ancient man's death, the researchers said.
"It was very surprising, because we didn't really expect to find compete red blood cells," study leader Albert Zink, a biological anthropologist at the European Academy of Bozen, was quoted as saying by LiveScience.
"We hoped to find maybe some remnants or shrunken red blood cells, but these are looking like a modern-day sample; the dimensions are the same," Zink said.
The Iceman was so well preserved that scientists could estimate his age (about 45), his health, his last meals (that included red deer meat with herb bread) and even his probable cause of death, an arrow wound to the shoulder that sliced an artery. But none had ever found blood cells in the his corpse.
In the study, Zink and his colleagues took tissue samples from Otzi's arrow wound and from an earlier wound on his hand. Using a light microscope, they identified round objects that looked a bit like red blood cells, Zink said. But to be sure, the researchers needed more advanced technology.
They used a device called atomic force microscope, which works by "feeling" rather than "seeing" an object, and found that the roundish shapes were indeed red blood cells.
"They have the typical form, this kind of doughnut-like shape of red blood cells. The dimensions are the same in modern-day samples, so we were really quite sure these were red blood cells that had been preserved for 5,000 years," Zink explained. (More) PTI SKP AKJ
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