Send to

Choose Destination
Blood. 2008 Jan 1;111(1):236-42. Epub 2007 Sep 17.

Leukemia-associated antigen-specific T-cell responses following combined PR1 and WT1 peptide vaccination in patients with myeloid malignancies.

Author information

Stem Cell Allotransplantation Section, Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892-1201, USA.


We describe the safety and immunogenicity of a combined vaccine of 2 leukemia-associated antigenic peptides, PR1 and WT1. Eight patients with myeloid malignancies received one subcutaneous dose each of PR1 and WT1 vaccines in Montanide adjuvant, with granulocyte-macrophage colony-stimulating factor. Patients were reviewed weekly for 4 weeks to monitor toxicity and immunologic responses. Toxicity was limited to grades 1 to 2. Using peptide/HLA-A 0201 tetramers and intracellular interferon-gamma staining, CD8(+) T cells against PR1 or WT1 were detected in 8 of 8 patients after a single vaccination. To monitor the kinetics of vaccine-induced CD8(+) T-cell responses and disease regression after vaccination, absolute PR1 and WT1(+)CD8(+) T-cell numbers and WT1 expression were studied weekly after vaccination. Responses occurred as early as 1 week after vaccination. After vaccination, the emergence of PR1 or WT1(+)CD8(+) T cells was associated with a decrease in WT1 mRNA expression as a marker of minimal residual disease, suggesting a vaccine-driven antileukemia effect. Conversely, loss of response was associated with reappearance of WT1 transcripts (P < .01). This is the first demonstration that a combined PR1 and WT1 vaccine is immunogenic. These results support further studies of combination immunization strategies in leukemia patients.


[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center