BCR-ABL is not an immunodominant antigen in chronic myelogenous leukemia

08-08-2006

According to a study from Germany, "In the present study, we analyzed the involvement of the BCR-ABL protein in the induction of antigen-specific CTL in order to develop an immunotherapeutic approach in patients with chronic myelogenous leukemia (CML). To accomplish this, we generated dendritic cells (DC) in vitro and electroporated them with various sources of RNA harboring the chimeric herabl transcript."

"These genetically engineered DCs were used as antigen-presenting cells for the induction of CTLs. By applying this approach, we found that the CTLs induced by DCs transfected with RNA extracted from bcr-abl-positive K-562 cells or CML blasts lysed DCs transfected with the corresponding RNA, but failed to recognize epitopes derived from the chimeric BCR-ABL fusion protein in Cr-51-release assays. In contrast, they were able to lyse autologous DCs electroporated with RNA isolated from patients with acute myeloid leukemia, indicating that antigens shared among these malignant cells are involved and recognized by these CTLs," wrote F. Grunebach and colleagues, University of Tubingen.

The researchers concluded: "In patients with CNM in complete cytogenetic remission during IFN-alpha treatment, we detected some reactivity of CD8+ T cells against BCR-ABL in IFN-gamma ELISPOT assays, which was weaker as compared with proteinase 3 (PR3)-or prame-directed responses, suggesting that the BCR-ABL protein is less immunogenic as compared with other CML-derived antigens."

Grunebach and colleagues published the results of their research in Cancer Research (BCR-ABL is not an immunodominant antigen in chronic myelogenous leukemia. Cancer Res, 2006;66(11):5892-5900).

For additional information, contact P. Brossart, University of Tubingen, Dept. of Internal Medicine 2, Otfried Muller STr 10, D-72076 Tubingen, Germany.

The publisher of the journal Cancer Research can be contacted at: American Association Cancer Research, 615 Chestnut St., 17TH Floor, Philadelphia, PA 19106-4404, USA.

Keywords: Tubingen, Germany, Acute Myeloid Leukemia, Biological Therapy, Biotechnology, Chronic Myelogenous Leukemia, Chronic Myeloid Leukemia, Genetic Engineering, Genetics, Immunology, Immunotherapy, Neurology, Oncology.

This article was prepared by Clinical Oncology Week editors from staff and other reports. Copyright 2006, Clinical Oncology Week via NewsRx.com.