In their study Wang et al.1 clearly characterize Cyclin D1 as a tumor antigen in mantle cell lymphoma. They show that T cells specific for the epitope LLGATCMFV (p101) can be generated from peripheral blood of normal donors and cancer patients that recognized HLA-matched primary tumor cells. Surprisingly, the authors report that they had to choose a heteroclitic approach due to a lack of a high-affinity natural epitope within the protein.
These findings are in contrast to our own, previously published2 and unpublished observations: For a total of six peptides we observed intermediate-to-good HLA-A*0201 binding in cellular binding assays including the peptides p22 and p101 studied by the authors. (Figure 1b) For p101, we also identified an analogous HLA-A*0201 binding decameric peptide (LLGATCMFVA) with comparable binding properties. Correspondingly, generation of peptide-specific cytotoxic T-lymphocyte (CTL) was possible in 9/10 donors for p101 and 3/3 donors for the p101 10 mer. (Figure 1a)
The authors chose not to characterize p22 as an immunogen due to low solubility of the heteroclitic peptide. On the basis of the results from our HLA-binding studies we did indeed attempt expansion of Cyc22 (p22) specific CD8+ T cell, which was successful in 2/2 donors.3 Furthermore, using the above strategy we identified p228 (RLTRFLSRV) as an immunogenic HLA-A0201-binding peptide that is recognized by T cells. (Figure 1a, b)
Our findings are supported by earlier observations made by Staus and colleagues4 who also report good HLA-A*0201 binding properties of p101. However, these earlier studies also failed to expand T cells specific for the native p101 in an autologous setting. They circumvented this by generating T cells from HLA-A*0201 donors that recognized the epitope in the context of HLA-A*0201. One possible explanation for this discrepancy is that we used a T-cell expansion system based on CD40-activated B cells as antigen-presenting cell, which was developed for high efficiency ex vivo T-cell expansion. Such T-cell expansion systems have previously been identified as a major needle hole of reverse immunology epitope validation.5 In our experience, this system is superior to the use of T2 cells as well as TNF-α (tumor necrosis factor-α) (and not CD40L) matured dendritic cells in the expansion of antigen-specific T cells, especially when they are loaded with significantly higher amounts of peptide than 1 μg (Wang et al.1: 20 μg).6, 7
Comparing native and modified epitopes it is crucial to consider T cell avidity, as this can be negatively affected by amino acid substitution.8, 9 Figure 1d shows subcloning of a bulk Cyc101-9-specific T-cell line (Figure 1c) and subsequent peptide dilution. The range of avidity observed was from intermediate to high. Importantly, only high-affinity T cells recognized CycD1+/HLA-A*0201+ myeloma cell line U266 (Figure 1e), as well as primary mantle cell lymphoma and plasma cell leukemia.2 These observations suggest that T cells of sufficient avidity can be generated using the native peptide and that it would be interesting to know the avidity of the T cells in the study by Wang et al. In the long term, it remains to be determined, whether the heteroclitic approach harbors any advantages for clinical immunotherapy and whether a combination of the two might prove beneficial.
Our observations confirm the notion by Wang et al. that the universally expressed tumor antigen Cyclin D1 is an exciting target for immunotherapy, not only in mantle cell lymphoma, as CCND1 is overexpressed in several solid tumors, has little expression in normal tissue and its expression is critically linked to tumor growth.
Conflict of interest
The authors declare no conflict of interest.
Wang M, Sun L, Qian J, Han X, Zhang L, Lin P et al. Cyclin D1 as a universally expressed mantle cell lymphoma-associated tumor antigen for immunotherapy. Leukemia 2009; 23: 1320–1328.
Kondo E, Maecker B, Weihrauch MR, Wickenhauser C, Zeng W, Nadler LM et al. Cyclin D1-specific cytotoxic T lymphocytes are present in the repertoire of cancer patients: implications for cancer immunotherapy. Clin Cancer Res 2008; 14: 6574–6579.
Kondo E, Gryschok L, Schultze JL, von Bergwelt-Baildon MS . Using CD40-activated B cells to efficiently identify epitopes of tumor antigens. J Immunother 2009; 32: 157–160.
Sadovnikova E, Jopling LA, Soo KS, Stauss HJ . Generation of human tumor-reactive cytotoxic T cells against peptides presented by non-self HLA class I molecules. Eur J Immunol 1998; 28: 193–200.
Kessler JH, Melief CJ . Identification of T-cell epitopes for cancer immunotherapy. Leukemia 2007; 21: 1859–1874.
Alexander-Miller MA, Leggatt GR, Berzofsky JA . Selective expansion of high- or low-avidity cytotoxic T lymphocytes and efficacy for adoptive immunotherapy. Proc Natl Acad Sci USA 1996; 93: 4102–4107.
Kondo E, Maecker B, Draube A, Klein-Gonzalez N, Shimabukuro-Vornhagen A, Schultze JL et al. The shared tumor associated antigen cyclin-A2 is recognized by high-avidity T-cells. Int J Cancer 2009, E-pub ahead of print 8 June 2009, DOI: 10.1002/ijc.24629.
Speiser DE, Baumgaertner P, Voelter V, Devevre E, Barbey C, Rufer N et al. Unmodified self antigen triggers human CD8T cells with stronger tumor reactivity than altered antigen. Proc Natl Acad Sci USA 2008; 105: 3849–3854.
Rubio V, Stuge TB, Singh N, Betts MR, Weber JS, Roederer M et al. Ex vivo identification, isolation and analysis of tumor-cytolytic T cells. Nat Med 2003; 9: 1377–1382.
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von Bergwelt-Baildon, M., Shimabukuro-Vornhagen, A., Wendtner, C. et al. Identification of native, immunogenic peptides from Cyclin D1. Leukemia 24, 209–211 (2010) doi:10.1038/leu.2009.184
Cancer Biology & Therapy (2013)