ATLANTA, Dec. 11 /PRNewswire/ -- Through the use of a novel antibody, scientists may be able to target the specific cells that lead to a common form of leukemia, according to a study to be presented today during the 47th Annual Meeting of the American Society of Hematology (ASH).
Acute myeloid leukemia (AML) is the result of maverick stem cells in the bone marrow producing unchecked numbers of immature white blood cells, called myeloid cells. Nearly 12,000 new cases of AML have been diagnosed in the United States this year.
“When I was training in hematology in the 1960s, AML was not curable. Now many, but not all, patients can be cured,” said James N. George, M.D., professor of medicine at the University of Oklahoma Health Sciences Center and President of ASH. “This study provides important new insights for further improving our ability to treat this once inevitably fatal disease.”
Different kinds of stem cells can be distinguished by different molecular markers on their surface. Stem cells characterized by the presence of the CD34 marker and the absence of the CD38 marker (CD34+CD38-) appear to be the initiation point for AML. Sometimes these cells can survive even under intense chemotherapy, and, when found in high frequency after treatment, correlate to a return of the cancer and high mortality.
However, as stem cells are rare, they are hard to find. Previous research indicated that myeloid cells have a marker on their surface called CLL-1 that could be detected by a particular protein called anti-CLL-1 antibody. Researchers wanted to see if this antibody could also detect hidden bastions of the CD34+CD38- stem cells in AML patients in remission.
In the study, the antibody detected CD34+CD38- stem cells in 77 out of 89 AML patients at the time of diagnosis. CLL-1 expression in CD34+CD38- cells of control bone marrows was virtually absent. For those AML patients in remission who were CLL-1 positive, the ratio of CLL-1 positive AML stem cells to normal (CLL-1 negative) stem cells correlated to the probability of relapse. Therefore, patients in remission who are found to have dormant CD34+CD38- cells in their marrow are ideal candidates for antibody therapy.
According to senior study author Gerrit Jan Schuurhuis, Ph.D., associate professor, VU University Medical Center, Amsterdam, The Netherlands, “The reliability of this antibody to detect and quantify the particular stem cells that foreshadow a poor prognosis for AML patients in remission means that scientists may now have the ability to hone in on these specific cells and target them for treatment.”
The American Society of Hematology (www.hematology.org) is the world’s largest professional society concerned with the causes and treatment of blood disorders. Its mission is to further the understanding, diagnosis, treatment, and prevention of disorders affecting blood, bone marrow, and the immunologic, hemostatic, and vascular systems, by promoting research, clinical care, education, training, and advocacy in hematology.
The American Society of Hematology
CONTACT: Leslie Priest, Spectrum Science Communications, +1-202-955-6222,lpriest@spectrumscience.com; Aislinn Raedy, American Society of Hematology,+1-202-776-0544, araedy@hematology.org, On-site (12/10-12/13),+1-404-222-5705
Web site: http://www.hematology.org/