Embattled stem cell scientist says charges against him false

Italian scientist Dr. Paolo Macchiarini was once considered a pioneer in regenerative medicine, credited with creating the world's first windpipe partially made from a patient's own stem cells.

But in the last year, Macchiarini has been charged with falsifying his resume, and accused of scientific misconduct and misrepresenting his work. Macchiarini was fired last week by Sweden's Karolinska University for various reasons, including breaching the institution's "fundamental values" and damaging its reputation.

In an email Tuesday night to the Associated Press, Macchiarini disputed the accusations.

"The allegations that have been made against me are entirely false," he said. "I am now in the process of instructing lawyers to defend my reputation vigorously." Macchiarini said he could not share more details.

Macchiarini's research was once thought to be revolutionary in the field of regenerative medicine, as scientists have competed to find ways of growing organs in laboratories.

Numerous concerns have been raised about his work, including whether he misrepresented the condition of his patients and whether consent was properly obtained. A Swedish documentary that suggested some of Macchiarini's patients were "tricked or talked into undergoing surgery" was described by Karolinska as "truly alarming."

The university's first investigation into Macchiarini found him guilty of scientific misconduct while the second cleared him. A third investigation is ongoing.

The Royal Swedish Academy of Sciences also accused Macchiarini of "ethically indefensible working methods." It said was "deeply unfortunate" that the journal Lancet has not made any changes to Macchiarini's paper on a stem cell windpipe to reflect that the patient suffered serious side effects and later died. The published paper said "there were no major complications."

The Lancet said Macchiarini should be considered innocent until proven guilty. Lancet editor Dr. Richard Horton said there are no immediate plans to retract Macchiarini's paper and that they are awaiting the verdict of the third investigation.

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