| |
|
|
|
|
|
|
|||
|
Blood, 1 August 2005, Vol. 106, No. 3, pp. 938-945. Prepublished online as a Blood First Edition Paper on April 12, 2005; DOI 10.1182/blood-2004-12-4787.
IMMUNOBIOLOGY Identification and characterization of epitopes of the receptor for hyaluronic acidmediated motility (RHAMM/CD168) recognized by CD8+ T cells of HLA-A2positive patients with acute myeloid leukemiaFrom the Third Department of Internal Medicine and Institute for Pathology, University of Ulm, Germany; Ludwig Institute for Cancer Research (LICR), Lausanne Branch, University of Lausanne, Epalinges, Switzerland; LICR New York Branch, Memorial Sloan-Kettering Cancer Center, NY; and Institute for Immunogenetics and Clinical Transfusion Medicine, German Red Cross, Ulm, Germany.
The receptor for hyaluronic acidmediated motility (RHAMM/CD168) has been described as a leukemia-associated antigen. To define T-cell epitopes of RHAMM/CD168 toward specific immunotherapies for acute myeloid leukemia (AML), 10 potential HLA-A2binding RHAMM/CD168 peptides (R1 to R10) were synthesized based on computer algorithms and screened by enzyme-linked immunospot (ELISPOT) analysis using CD8+ T cells isolated from peripheral blood (PB) of patients with AML and healthy donors. We found that CD8+ cells from 7 of 13 (54%) patients with AML presensitized with peptides R3 (ILSLELMKL) or R5 (SLEENIVIL) specifically recognized T2 cells pulsed with R3 (39%) or R5 (15%) peptide. In contrast, only 4 of 21 (19%) healthy volunteers had CD8+ cells reactive with R3- or R5-pulsed T2 cells after presensitization. The presence of R3 peptidespecific effector T cells in the peripheral blood of patients with AML could be confirmed by staining as HLA-A2/R3 peptide tetramer+ CCR7-CD45RA+ cells. In chromium-51 release assays, peptide-primed CD8+ T cells from patients with AML were able to lyse RHAMM/CD168 peptidepulsed T2 cells, AML blasts, and dendritic cells generated thereof (AML DCs). Transfection of COS7 cells with RHAMM/CD168 cDNA revealed that peptides R3 and R5 are naturally processed epitopes of RHAMM/CD168 that are presented in an HLA-A2restricted manner. In summary, RHAMM/CD168 is a promising target for immunotherapies in patients with AML, and we have therefore initiated a clinical vaccination trial with R3 peptide. Because RHAMM/CD168 is also expressed in various other hematologic malignancies and solid tumors, vaccines targeting this antigen may have even wider application.
This article has been cited by other articles:
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Copyright © 2005 by American Society of Hematology Online ISSN: 1528-0020 | |||||||||