Promising stem cell therapy for leukemia patients

April 2, 2013, Fraunhofer-Gesellschaft
Scientists are studying how antibodies can best protect the healthy tissue of leukemia patients. Credit: Dirk Mahler

Leukemia patients receive a bone marrow transplant, which allows them to build a "new" immune system. However, this immune system not only attacks cancer cells but healthy tissue too. Special antibodies will be used to protect healthy tissue in future.

Not too long ago, leukemia left us with no chance. Today doctors can give patients hope by transplanting bone marrow, the starting point of a "new" immune system. These transplanted cells replace the diseased, blood-building stem cells in the bone marrow and take over their job of producing healthy , while also destroying . The problem is that this immune system originates from a foreign body and therefore can also attack healthy tissue in the patient. The skin, liver, and intestine are most affected by these attacks – their cells can be destroyed and the organs damaged, sometimes so severely as to cause . The medical term for this phenomenon is graft-versus-host disease (GvHD), and the scale of the problem posed by this misdirected immune response is illustrated by statistics revealing that up to 50 percent of all patients ultimately suffer from GvHD-induced damage; in up to 20 percent of cases this damage is fatal. Not to ignore the further risk: that one in five leukemia patients suffer a relapse after the transplant.

In order to combat the cancer effectively, doctors give leukemia patients chemotherapy and before the transplant. These treatments destroy the patient's entire blood-building system, creating space for the donor's healthy cells. Any that might survive this treatment are identified and destroyed by the new immune cells. So that the "foreign" immune system does not turn against healthy tissue, doctors additionally give patients immunosuppressants to artificially suppress the immune system. There is a to be struck here, as immunosuppressants not only inhibit GvHD but also the desired immune response, i.e. killing off the cancer cells.

Minimizing the risk of a misdirected immune reaction

Researchers at the Fraunhofer Institute for Cell Therapy and Immunology IZI in Leipzig are investigating how to improve the situation for leukemia sufferers. "Our goal is to avoid GvHD without changing how the new immune effect acts on the tumor," says Dr. Stephan Fricke, head of the Immune Tolerance unit at the IZI and doctor at the Department of Hematology and Oncology, University Hospital Leipzig. "Our hopes are pinned on monoclonal antibodies, which specifically bind to the surface of immune cells and prevent the immune cells reacting adversely with the patient's tissue." It's particularly important that the antibodies also act on the blood to be transplanted and on all that develop from them. This allows researchers to modulate the cells in advance of transplantation, causing them to "tolerate" the patient's healthy tissue instead of attacking it. "We're then able to effectively reduce the risk of a GvHD without any side effects," explains Fricke. The antibodies do not alter the against remaining cancer cells – they are still destroyed as before. This reduces the risk of leukemia coming back after the transplant.

IZI scientists are currently collaborating with their colleagues from the Translational Centre for Regenerative Medicine at the Universität Leipzig on research into the cellular foundations of these effects. What is the optimum point at which to add the antibodies to the donor bone marrow? How many antibodies should be used? Setting out to answer these questions, researchers first simulate both and the human immune system using a variety of established models. They can then determine all relevant parameters based on the simulations.

The researchers have already provided proof of principle, i.e. they were able to demonstrate that the therapy works. Now initial tests are underway on mice with a human immune system. The scientists hope that a clinical study can begin before the year is out.

Explore further: Antibodies from rabbits improve survival and relapse outcomes of leukemia and myelodysplasia

Related Stories

Antibodies from rabbits improve survival and relapse outcomes of leukemia and myelodysplasia

July 6, 2012
Researchers at Virginia Commonwealth University (VCU) Massey Cancer Center's Bone Marrow Transplant Program have demonstrated that the use of antibodies derived from rabbits can improve the survival and relapse outcomes of ...

Mini-molecule governs severity of acute graft vs. host disease, study finds

March 12, 2012
Researchers have identified a molecule that helps control the severity of graft-versus-host disease, a life-threatening complication for many leukemia patients who receive a bone-marrow transplant.

Southampton scientists to investigate ways to prevent life-threatening complications in transplant patients

August 21, 2012
Scientists from the University of Southampton have received a grant from the blood cancer charity Leukaemia & Lymphoma Research to explore ways of preventing life-threatening side effects in patients receiving bone marrow ...

HIV drug reduces graft-vs.-host disease in bone marrow transplant patients

July 11, 2012
An HIV drug that redirects immune cell traffic significantly reduces the incidence of a dangerous complication that often follows bone marrow transplants for blood cancer patients, according to research from the Perelman ...

Biomarker detects graft-versus-host-disease in cancer patients after bone marrow transplant

October 21, 2011
A University of Michigan Health System-led team of researchers has found a biomarker they believe can help rapidly identify one of the most serious complications in patients with leukemia, lymphoma and other blood disorders ...

No survival advantage with peripheral blood stem cells versus bone marrow

October 19, 2012
(Medical Xpress)—Claudio Anasetti, M.D., chair of the Department of Blood & Marrow Transplant at Moffitt Cancer Center, and colleagues from 47 research sites in the Blood and Marrow Transplant Clinical Trials Network conducted ...

Recommended for you

Ketogenic diet reduces body fat in women with ovarian or endometrial cancer

September 19, 2018
Women with ovarian or endometrial cancer who followed the ketogenic diet for 12 weeks lost more body fat and had lower insulin levels compared to those who followed the low-fat diet recommended by the American Cancer Society, ...

Researchers find adult stem cell characteristics in aggressive cancers from different tissues

September 19, 2018
UCLA researchers have discovered genetic similarities between the adult stem cells responsible for maintaining and repairing epithelial tissues—which line all of the organs and cavities inside the body—and the cells that ...

Colon cancer is caused by bacteria and cell stress

September 19, 2018
Researchers at Technical University Munich have reported findings related to the development of colon cancer. "We originally wanted to study the role of bacteria in the intestines in the development of intestinal inflammation," ...

Eating foods with low nutritional quality ratings linked to cancer risk in large European cohort

September 18, 2018
The consumption of foods with higher scores on the British Food Standards Agency nutrient profiling system (FSAm-NPS), reflecting a lower nutritional quality, is associated with an increased risk of developing cancer, according ...

CRISPR screen reveals new targets in more than half of all squamous cell carcinomas

September 18, 2018
A little p63 goes a long way in embryonic development—and flaws in p63 can result in birth defects like cleft palette, fused fingers or even missing limbs. But once this early work is done, p63 goes silent, sitting quietly ...

Could the zika virus fight the brain cancer that killed john McCain?

September 18, 2018
(HealthDay)—Preliminary research in mice suggests that the Zika virus might be turned from foe into friend—enlisted to curb deadly glioblastoma brain tumors.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.