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A inquiry has concluded that Paolo Macchiarini, a surgeon who transplanted artificial windpipes, committed research misconduct.

A inquiry has concluded that Paolo Macchiarini, a surgeon who transplanted artificial windpipes, committed research misconduct.


Artificial trachea researcher responds to misconduct report

Surgeon Paolo Macchiarini has now responded to the report, released last month, that concluded he was guilty of scientific misconduct as part of his clinical testing of artificial tracheas that he has helped pioneer. Macchiarini’s 23-page response disputes key parts of the misconduct report’s findings, saying that the investigator, Bengt Gerdin, a professor emeritus of surgery at Uppsala University in Sweden, did not have access to all the relevant clinical records describing patient conditions. As a result, the surgeon writes in an opening note of his response, there has been “a potentially disastrous miscarriage of justice.”

Over the past decade, Macchiarini has transplanted tissue-engineered tracheae into more than a dozen people whose own windpipes were damaged by disease or injury. At the Karolinska Institute in Stockholm, he transplanted into three patients artificial tracheae that consisted of a polymer scaffold seeded with the patient’s own stem cells. The stem cells were supposed to grow over the scaffold and ultimately form a living graft. Two of the those recipients have died, however, and the other remains in intensive care at a Karolinska hospital nearly 3 years after receiving the transplant.

The report by Gerdin, whom the Karolinska requested conduct an investigation after whistleblowers lodged complaints, concluded that the series of clinical reports published by Macchiarini and his colleagues did not accurately describe the condition of patients; Gerdin said that constituted scientific misconduct. In particular, a paper in The Lancet describing a patient’s status 5 months after the transplant claimed that the patient was doing well and the graft was starting to show evidence of being covered by growing cells. However, Gerdin concluded, the clinical information in the paper was based on the patient’s condition when he was initially discharged from Karolinska, 1 month after the transplant. Gerdin’s investigation was not able to find any clinical information about the patient at 5 months following the transplant. Shortly before the paper was published—roughly 5.5 months after the transplant—the patient was readmitted to the Karolinska hospital with complications.

Macchiarini says in his response that he has now gathered additional clinical records that corroborate the description of the patient. The response does not explain why the patient was readmitted to Karolinska and the additional records are also not public, because of patient confidentiality. However, Macchiarini told ScienceInsider that the patient was readmitted for routine post-operative care.

Macchiarini’s response to the Gerdin report was one of more than a dozen filed with Karolinska from the researchers who initially brought misconduct allegations against Macchiarini, as well as other researchers and physicians involved in the transplant. The responses total roughly 1000 pages, a Karolinska spokesperson said today. ScienceInsider received the responses from Karolinska, which is required to make them public.

The vice chancellor of the Karolinska Insitute will assess the responses and ultimately make a decision on how to respond to Gerdin’s misconduct allegations and others matters in his report.  Given the volume of material involved, the spokesperson says, the timing of the decision is uncertain.

*The item has been updated to include an additional response from Macchiarini.