Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Clinical Trial
. 2010 Jul 15;116(2):171-9.
doi: 10.1182/blood-2009-10-250993. Epub 2010 Apr 16.

Vaccination with synthetic analog peptides derived from WT1 oncoprotein induces T-cell responses in patients with complete remission from acute myeloid leukemia

Peter G Maslak  1 , Tao Dao, Lee M Krug, Suzanne Chanel, Tatyana Korontsvit, Victoria Zakhaleva, Ronghua Zhang, Jedd D Wolchok, Jianda Yuan, Javier Pinilla-Ibarz, Ellin Berman, Mark Weiss, Joseph Jurcic, Mark G Frattini, David A Scheinberg
Affiliations
Clinical Trial

Vaccination with synthetic analog peptides derived from WT1 oncoprotein induces T-cell responses in patients with complete remission from acute myeloid leukemia

Peter G Maslak et al. Blood. .

Abstract

A pilot study was undertaken to assess the safety, activity, and immunogenicity of a polyvalent Wilms tumor gene 1 (WT1) peptide vaccine in patients with acute myeloid leukemia in complete remission but with molecular evidence of WT1 transcript. Patients received 6 vaccinations with 4 WT1 peptides (200 microg each) plus immune adjuvants over 12 weeks. Immune responses were evaluated by delayed-type hypersensitivity, CD4+ T-cell proliferation, CD3+ T-cell interferon-gamma release, and WT1 peptide tetramer staining. Of the 9 evaluable patients, 7 completed 6 vaccinations and WT1-specific T-cell responses were noted in 7 of 8 patients. Three patients who were HLA-A0201-positive showed significant increase in interferon-gamma-secreting cells and frequency of WT1 tetramer-positive CD8+ T cells. Three patients developed a delayed hypersensitivity reaction after vaccination. Definite related toxicities were minimal. With a mean follow-up of 30 plus or minus 8 months after diagnosis, median disease-free survival has not been reached. These preliminary data suggest that this polyvalent WT1 peptide vaccine can be administered safely to patients with a resulting immune response. Further studies are needed to establish the role of vaccination as viable postremission therapy for acute myeloid leukemia.

Trial registration: ClinicalTrials.gov NCT00398138.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Survival curves for vaccinated patients. (A) Disease-free survival. (B) Overall survival.
Figure 2
Figure 2
WT1 transcript levels in vaccinated patients. (A) Relapsed patients: increases in WT1 transcripts were large at the time of or just before relapse. The absolute changes occur over orders of magnitude and are shown using a logarithmic scale. (B) Remission patients: variations in transcript levels were comparatively small, either trending toward decrease or stable at very low levels. Minor variations are best appreciated using a linear scale.
Figure 3
Figure 3
CD4+ proliferation. (A) CD4+ T cells from pre (i), postvaccine 3 (ii), and postvaccine 6 (iii) vaccinations from patient 5 (A0201+) were incubated with indicated peptides at 20 μg/mL or 50 μg/mL for 5 days, and 1 μCi [3H]-thymidine was added to the cultures for 20 hours. The cell proliferation was determined by [3H]-thymidine incorporation. Data are mean ± SD from quadruplicate cultures. After 3 vaccinations, cell proliferation increased 54-fold to 331, 37-fold to 427, 4.2-fold to 122A1, and 2.6-fold to 122A (P = .032) at a concentration of 50 μg/mL peptides tested. There was no significant dose dependency of the peptides, and similar responses were also seen after 6 vaccinations. (B) Time course of CD4+ response: CD4+ T-cell responses of 3 patients who completed 12 vaccinations were calculated by the fold increase of the CD4+ T-cell proliferation against 331, 427, and 122A1 peptides over irrelevant peptide B2A2 long at a concentration of 50 μg/mL. Responses at T9 and T12 were not tested for patient 2 (A0201+) because of clinical relapse before those time points. CD4+ T-cell responses were elicited and maintained throughout vaccination, although the magnitude to each peptide with respect to vaccination times varied among patients.
Figure 4
Figure 4
IFN-γ secretion. CD3+ T cells from patient 5 were stimulated twice with WT1-A (native), WT1-A1 (analog) (A), 122A (native), or 122A1 (analog) (B) peptides. IFN-γ–secreting T cells were measured by ELISPOT assay after challenge with the indicated peptides. Controls were: no peptide (only CD14+ APCs) or with irrelevant Ewing sarcoma–derived peptide (EW) (A) or JAK-2 derived peptide (JAK-2 DR) (B). Data are mean ± SD from quadruplicate cultures from prevaccine (i), postvaccine 3 (ii), and postvaccine 6 (iii). Results indicate that a WT1-A–specific response can be generated not only by the HLA-A0201 restricted peptide but also by the HLA-DR peptide (WT1 122A1) that contains the embedded short sequence, demonstrating the processing and presentation of the WT1-A epitope.
Figure 5
Figure 5
Tetramers. CD3+ T cells from the same culture described in Figure 3 were stained with WT1-A/HLA-A0201 tetramer with mAbs to CD8 and other T-cell markers. Percentage of tetramer-positive CD8+ T cells (number shown in upper left corner of each histogram) were gated on CD3+ events after passing through the small lymphocyte gate. Cells from prevaccine, postvaccine 3, and postvaccine 6 are shown as T0, T3, and T6, respectively. The data are representative staining from triplicate cultures. After vaccination, a robust increase in percentage of WT1-specific CD8+ T cells was noted in cultures with WT1-A, WT1-A1, and 122A1 peptides (top axis). Peptide 122A stimulation induced a weak but significant response.
Figure 6
Figure 6
Cytotoxicity assay. CD3+ T cells from patient 5 were stimulated with WT1-A or WT1A1 peptides twice as described in Figure 5. Target cells used included the ALL derived 697 cell line (A0201+; WT1+) and the B-cell lymphoma cell line SKLY-16 (A0201+; WT1−). The cytotoxicity of the T cells was measured using a standard 51Cr release assay. The SKLY-16 cells pulsed with WT1-A (SKLY-WT1A) or an irrelevant Ewing sarcoma–derived HLA-A0201 binding peptide (SKLY-EW) were used as positive and negative controls for the specificity of killing. Effector/target (E:T) ratios are indicated on the x-axis. Data demonstrate T cell–specific killing against WT1 plus HLA-matched targets.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Frattini MG, Maslak PG. Strategy for incorporating molecular and cytogenetic markers into acute myeloid leukemia therapy. J Natl Compr Canc Netw. 2008;6(10):995–1002. - PubMed
    1. Virappane P, Gale R, Hills R, et al. Mutation of the Wilms' tumor 1 gene is a poor prognostic factor associated with chemotherapy resistance in normal karyotype acute myeloid leukemia: the United Kingdom Medical Research Council Adult Leukaemia Working Party. J Clin Oncol. 2008;26(33):5429–5435. - PubMed
    1. Paschka P, Marcucci G, Ruppert AS, et al. Wilms' tumor 1 gene mutations independently predict poor outcome in adults with cytogenetically normal acute myeloid leukemia: a Cancer and Leukemia Group B study. J Clin Oncol. 2008;26(28):4595–4602. - PMC - PubMed
    1. Scheibenbogen C, Letsch A, Thiel E, et al. CD8 T-cell responses to Wilms tumor gene product WT1 and proteinase 3 in patients with acute myeloid leukemia. Blood. 2002;100(6):2132–2137. - PubMed
    1. Rezvani K, Grube M, Brenchley JM, et al. Functional leukemia-associated antigen-specific memory CD8+ T cells exist in healthy individuals and in patients with chronic myelogenous leukemia before and after stem cell transplantation. Blood. 2003;102(8):2892–2900. - PubMed

Publication types

MeSH terms

Associated data