Hisashi Moriguchi, a Japanese researcher who had said he implemented the world's first clinical trial using a trailblazing stem cell technology, has admitted that most of what he claimed in an academic conference presentation about the procedure was false. At a news conference in New York, Moriguchi said, "While the treatment was implemented, it was only one procedure. At the end of the day, I lied."

He earlier said treatment using induced pluripotent stem cells was conducted on a total of six people, including the first case on a man with a failing heart in February this year. He also corrected the timing of the trial to June last year. He said he was present during the procedure allegedly undertaken in the United States and showed his passport record to reporters. Massachusetts General Hospital in Boston, where he claimed that the trial was conducted, said Friday there are no records of him having undertaken the procedure or of applying for approval to carry it out.

Moriguchi has been staying in New York after a poster presentation of his alleged treatment at a two-day stem cell research conference at Rockefeller University. On the timing of the surgical procedure, Moriguchi said, "It wasn't February 12. Let me correct it. It was in the first half of June last year. I don't remember (the exact date) until I check it later. Six people were present there."

During the news conference, he also said the procedure was in fact conducted at another hospital in Boston, rather than MGH, affiliated with Harvard University. He said, "iPS cells were successfully cultured in a large volume and surgery was conducted. Since it can't be done alone, I needed help from many people concerned." The procedure required extracting immature cells from the patient's liver to create chemically induced pluripotent cells, which can turn into any type of body parts, according to Moriguchi. They were then turned into heart muscle cells for injections into the man's heart.

Citing a hearing from a doctor who has co-authored reports with Moriguchi, MGH said, "Dr. (Raymond) Chung has no knowledge of the clinical procedure that Dr. Moriguchi reported at a conference in New York recently. We cannot find any evidence of that procedure taking place at Massachusetts General Hospital," the hospital said in a statement. "No request to conduct that sort of clinical trial was ever submitted or approved by the hospital's institutional review board, which reviews and approves all studies involving human patients."

The hospital also said that "There is no evidence in the records of the Harvard University Institutional Review Board or the Institutional Review Board of Harvard Medical School of Moriguchi applying for permission to carry out any experiment of any kind."

Asked about the denial by the hospital on the institutional review board application, Moriguchi said, "It was probably because the application was made under the name of another doctor, not my name." Moriguchi also said that Chung was not involved in the trial in June last year.

On the earlier proclaimed credentials of a "physician assistant" licensed by the state of Massachusetts, he said, "I don't have it. I lied." Moriguchi, who graduated with a degree in nursing in Japan, is not a medical doctor. He also said during the alleged procedure in June last year, "I did injections myself. Of the 30 (injections), I did several shots" into the patient. A public relations official at the Massachusetts hospital said the hospital believes that the male heart-failure patient Moriguchi claimed to have been the first to receive the transplant does not exist.

The official said the hospital could not find any records showing that the procedure claimed to have been performed by Moriguchi was applied to a patient at the hospital during the time when he said the man received the transplant. Moriguchi identified himself as a visiting lecturer at Harvard University but the university has said he currently has no affiliation with the university or the hospital.

Citing Moriguchi, Kyodo News reported earlier that a team of researchers had transplanted artificial cardiac muscle cells developed from multipurpose stem cells into six heart-failure patients in the United States in the world's first clinical application of the so-called iPS cells. But further investigation by the news agency revealed that Moriguchi's claims in the initial announcement were groundless. Moriguchi, who did not appear in person at the conference in New York, said, "I was going to the conference. But I could not go because I had to spend time handling the mass media." His poster presentation was later withdrawn at the conference venue.