Category Archives: Transhuman News

Gene therapy developed at St. Jude Children's Research Hospital, University College London (UCL) and the Royal Free Hospital has transformed life for men with a severe form of hemophilia B by providing a safe, reliable source of the blood clotting protein Factor IX that has allowed some to adopt a more active lifestyle, researchers reported. The results appear in the November 20 edition of The New England Journal of Medicine.

In this study, participants received one of three doses of gene therapy that used a modified adeno-associated virus (AAV) 8 as the vector to deliver the genetic material for making Factor IX. The vector was administered as a single infusion into a peripheral vein in the arm of each participant.

Factor IX levels rose in all 10 men with severe hemophilia B following gene therapy and have remained stable for more than four years. Overall, episodes of spontaneous bleeding declined 90 percent. Use of Factor IX replacement therapy dropped about 92 percent in the first 12 months after the treatment with the investigational therapy.

In the six participants who received the highest gene therapy dose, levels of the blood-clotting protein increased from less than 1 percent of normal levels to 5 percent or more. The increase transformed their disease from severe to mild and enabled participation in sports such as soccer without the need for Factor IX replacement therapy or an increase in the risk of bleeding. Episodes of spontaneous bleeding and use of Factor IX replacement therapy declined for these patients more than 94 percent in the next 12 months.

Liver enzymes rose in four of the six patients who received the highest dose, possibly due to an immune response against the vector. The men had no symptoms and remained otherwise healthy. Their liver enzymes returned to the normal range following brief treatment with steroids.

Hemophilia B is caused by a mutation in the Factor IX gene that can result in dangerously low levels of the essential clotting protein. The disorder affects about 1 in 30,000 individuals, mostly men. For those with severe disease marked by Factor IX levels less than 1 percent of normal, scrapes and bumps are medical emergencies. Painful episodes of spontaneous bleeding can result in crippling joint damage early in life and an increased risk of potentially fatal bleeding within the brain.

"This study provides the first clear demonstration of the long-term safety and efficacy of gene therapy," said senior author Andrew Davidoff, M.D., chair of the St. Jude Department of Surgery. "The results so far have made a profound difference in the lives of study participants by dramatically reducing their risk of bleeding."

The paper's first and corresponding author, Amit Nathwani, M.D., Ph.D., added: "The data we are reporting mark a paradigm shift in treatment of hemophilia B and lay the groundwork for curing this major bleeding disorder." Nathwani is a faculty member at the UCL Cancer Institute, Royal Free Hospital and NHS Blood and Transplant. "The results also provide a solid platform for developing this gene transfer approach for treatment of other disorders ranging from other congenital clotting deficiencies like hemophilia A to inborn errors of metabolism such as phenylketonuria."

Prior to receiving gene therapy, seven of the 10 men received Factor IX replacement therapy at least once a week in order to prevent bleeding episodes. Others used replacement therapy as needed to halt bleeding or prior to surgeries.

Since joining the trial, four of the seven men ended the routine Factor IX injections. None have suffered spontaneous bleeding despite increased physical activity. "Some patients have not required clotting factor injections for more four years, which has been life changing," Nathwani said. Researchers estimated that overall spending on Factor IX replacement therapy for study participants is down more than $2.5 million.

Continued here:
Gene therapy provides safe, long-term relief for patients with severe hemophilia B

PUBLIC RELEASE DATE:

20-Nov-2014

Contact: Scott LaFee slafee@ucsd.edu 619-543-5232 University of California - San Diego @UCSanDiego

While investigating a rare genetic disorder, researchers at the University of California, San Diego School of Medicine have discovered that a ubiquitous signaling molecule is crucial to cellular reprogramming, a finding with significant implications for stem cell-based regenerative medicine, wound repair therapies and potential cancer treatments.

The findings are published in the Nov. 20 online issue of Cell Reports.

Karl Willert, PhD, assistant professor in the Department of Cellular and Molecular Medicine, and colleagues were attempting to use induced pluripotent stem cells (iPSC) to create a "disease-in-a-dish" model for focal dermal hypoplasia (FDH), a rare inherited disorder caused by mutations in a gene called PORCN. Study co-authors V. Reid Sutton and Ignatia Van den Veyver at Baylor College of Medicine had published the observation that PORCN mutations underlie FDH in humans in 2007.

FDH is characterized by skin abnormalities such as streaks of very thin skin or different shades, clusters of visible veins and wartlike growths. Many individuals with FDH also suffer from hand and foot abnormalities and distinct facial features. The condition is also known as Goltz syndrome after Robert Goltz, who first described it in the 1960s. Goltz spent the last portion of his career as a professor at UC San Diego School of Medicine. He retired in 2004 and passed away earlier this year.

To their surprise, Willert and colleagues discovered that attempts to reprogram FDH fibroblasts or skin cells with the requisite PORCN mutation into iPSCs failed using standard methods, but succeeded when they added WNT proteins - a family of highly conserved signaling molecules that regulate cell-to-cell interactions during embryogenesis.

"WNT signaling is ubiquitous," said Willert. "Every cell expresses one or more WNT genes and every cell is able to receive WNT signals. Individual cells in a dish can grow and divide without WNT, but in an organism, WNT is critical for cell-cell communication so that cells distinguish themselves from neighbors and thus generate distinct tissues, organs and body parts."

WNT signaling is also critical in limb regeneration (in some organisms) and tissue repair.

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Signaling molecule crucial to stem cell reprogramming