Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Kinder, gentler procedure gives superior results for stem cell transplants

14.12.2004


An improved stem cell transplant regimen that is well-tolerated and has a high success rate has been developed by researchers at Washington University School of Medicine in St. Louis. The procedure holds promise for treatment of blood and bone marrow disorders, immune dysfunction and certain metabolic disorders.

Designed for transplants that replace a patient’s bone marrow with stem cells from donor marrow, peripheral blood or umbilical cord blood, the procedure allows early recovery of immune function, nearly eliminates transplant rejection, and decreases the incidence and severity of "graft vs. host disease," a common complication in transplants.

Termed a "reduced-intensity" protocol, in pediatric patients it may minimize damage to sensitive growing tissues like the brain and reproductive organs.



The pilot study of the procedure is reported in the journal Bone Marrow Transplantation. It is available through advance online publication on Dec. 13 and will appear in a future print issue.

The regimen was administered to 11 pediatric and 5 adult patients at St. Louis Children’s and Barnes-Jewish hospitals and the Children’s Hospital of New Orleans who had non-malignant bone marrow or metabolic disorders such as sickle cell anemia, thalassemia or Hurler’s syndrome. Symptoms and disease parameters stabilized or improved in all patients that underwent successful transplants.

In a successful stem cell transplant, the donor stem cells become permanently established, or engrafted, in the patient’s bone marrow and continually produce healthy blood cells. To prevent the host immune system from destroying the foreign stem cells, physicians administer a pretransplant immune suppressing treatment.

"We wanted an approach that would effectively knock out the patient’s immune system to let the transplanted cells engraft, but then allow immune function to recover quickly," says study leader Shalini Shenoy, M.D., assistant professor of pediatrics and faculty member of the Siteman Cancer Center.

A key innovation in this study changes the timing of administering a powerful pretransplant conditioning drug. The drug, Campath-1H, targets and destroys several vital immune system components. Previous studies used Campath-1H in higher doses and gave the drug at transplant time. With such dosing, Campath stayed in the body for up to 56 days after the transplant.

"We give a short, three-day, lower-dose treatment of Campath, three weeks in advance of transplant," Shenoy says. "As a result, we ensure that Campath levels are lower by the time of transplant to help establish donor cells and allow early recovery of immune function."

With standard transplant protocols, immune function may not fully recover for a year or more, and during this time, the patient is highly susceptible to life-threatening infections. In this study, the patients’ immune function showed significant recovery by six months, and no major infections were encountered after this period.

Fourteen of the 16 patients had successful bone marrow engraftment of the donor stem cells and only one experienced late graft rejection, an unusually high rate of success according to Shenoy. Furthermore, the grafts took hold quickly. Donor stem cells had established in the bone marrow completely at one month, contrasting with other reduced-intensity protocols where donor engraftment is gradual and often takes many months.

The protocol also reduced the incidence and severity of graft vs. host disease, which occurs when transplanted immune cells attack various cells in the body. For the majority of patients who experienced graft vs. host disease, the symptoms were limited to the skin and were controlled with treatments that were later successfully withdrawn.

To minimize damage to still-growing tissues such as the brain and reproductive organs in pediatric patients, the protocol uses smaller doses of standard conditioning chemotherapeutic agents.

"In the past, physicians had to accept the potential for brain damage or sterility in pediatric patients treated with chemotherapy," Shenoy says. "We’re trying to provide treatments that protect developing tissues. We’ve had our first pregnancy and normal delivery in one of our stem cell transplant patients, so we think the protocol offers some hope."

Next, Shenoy plans to evaluate whether changing parameters and further reducing chemotherapy doses would enhance the protocol’s effectiveness. She will also conduct studies targeted at sickle cell anemia and chronic myelogenous leukemia to explore the potential for successful transplants in children with these disorders.

Gwen Ericson | EurekAlert!
Further information:
http://www.wustl.edu

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Taming 'wild' electrons in graphene

23.10.2017 | Physics and Astronomy

Mountain glaciers shrinking across the West

23.10.2017 | Earth Sciences

Scientists track ovarian cancers to site of origin: Fallopian tubes

23.10.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>