Telomerase (hTERT 611–626) serves as a tumor antigen in B-cell chronic lymphocytic leukemia and generates spontaneously antileukemic, cytotoxic T cells

Abstract In patients with B-cell chronic lymphocytic leukemia (B-CLL), the absolute number of T cells is increased. Although it has been suggested that these T cells might be tumor specific, concrete evidence for this hypothesis is lacking. We performed a detailed immunophenotypic analysis of the T-cell compartment in the peripheral blood of 28 patients with B-CLL (Rai 0, n = 12; Rai I-II, n = 10; Rai III-IV, n = 6) and 12 healthy age-matched controls and measured the ability of these patients to mount specific immune responses. In all Rai stages a significant increase in the absolute numbers of CD3+ cells was observed. Whereas the number of CD4+ cells was not different from controls, patients with B-CLL showed significantly increased relative and absolute numbers of CD8+ cells, which exhibited a CD45RA+CD27- cytotoxic phenotype. Analysis of specific immune responses with tetrameric cytomegalovirus (CMV)–peptide complexes showed that patients with B-CLL had significantly increased numbers of tetramer-binding CMV-specific CD8+ T cells. The rise in the total number of CD8+ cytotoxic T cells was evident only in CMV-seropositive B-CLL patients. Thus, our data suggest that in patients with B-CLL the composition of T cells is shifted toward a CD8+ cytotoxic cell type in an effort to control infections with persistent viruses such as CMV. Moreover, they offer an explanation for the high incidence of CMV reactivation in CLL patients treated with T cell–depleting agents, such as the monoclonal antibody (mAb) alemtuzumab (Campath; α-CD52 mAb). Furthermore, because in CMV-seronegative patients no increase in cytotoxic CD8+ T cells is found, our studies do not support the hypothesis that tumor-specific T cells account for T-cell expansion in B-CLL.

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T cells in B-cell chronic lymphocytic leukemia: quantitative assessment of cytotoxic and interleukin-2-producing lymphocyte precursors by limiting dilution analysis

Blood ◽

10.1182/blood.v73.6.1622.bloodjournal7361622 ◽

1989 ◽

Vol 73 (6) ◽

pp. 1622-1626

Author(s):

O Janssen ◽

C Nerl ◽

D Kabelitz

Keyword(s):

T Cells ◽

B Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Cytotoxic T Cells ◽

Interleukin 2 ◽

Lymphocytic Leukemia ◽

Limiting Dilution ◽

Cell Chronic Lymphocytic Leukemia

Controversy exists as to the functional capacity of T lymphocytes in patients with B-cell chronic lymphocytic leukemia (CLL). We have used a limiting dilution (LD) culture approach to quantitatively assess frequencies of proliferating lymphocyte precursors (PLP), cytotoxic lymphocyte precursors (CLP), and interleukin-2 (IL-2)-producing helper lymphocyte precursors (HLP). Unseparated mononuclear cells (MNC) or purified T cells (E+) and leukemic B cells (E-) were cocultured under LD conditions with irradiated OKT3 hybridoma cells in the absence (determination of HLP) or presence of recombinant IL-2 (determination of PLP and CLP). Under these conditions, low frequencies of PLP, HLP, and CLP (f = 1/65 to 1/4600) were measured in unseparated MNC of CLL patients. In contrast, purified T cells (50% to 92% CD3+) contained precursors of proliferating, IL-2-producing and cytotoxic T cells in similar frequency as did T cells from healthy control donors (f = 1/4 to 1/24). Leukemic B cells rigorously depleted of T cells did not give rise to measurable frequencies of PLP, HLP, or CLP (f less than 1/50.000) except in one CLL patient where a significant frequency (f = 1/1700) of HLP was consistently present in E- cells, despite the absence of growth-inducible PLP and CLP. Taken together, these results indicate that comparable numbers of IL-2-producing helper T cells and cytotoxic T cells are present in B-CLL patients and healthy controls, respectively. The data are discussed with respect to reported T cell abnormalities in B-CLL.

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T cells in B-cell chronic lymphocytic leukemia: quantitative assessment of cytotoxic and interleukin-2-producing lymphocyte precursors by limiting dilution analysis

Blood ◽

10.1182/blood.v73.6.1622.1622 ◽

1989 ◽

Vol 73 (6) ◽

pp. 1622-1626 ◽

Cited By ~ 9

Author(s):

O Janssen ◽

C Nerl ◽

D Kabelitz

Keyword(s):

T Cells ◽

B Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Cytotoxic T Cells ◽

Interleukin 2 ◽

Lymphocytic Leukemia ◽

Limiting Dilution ◽

Cell Chronic Lymphocytic Leukemia

Abstract Controversy exists as to the functional capacity of T lymphocytes in patients with B-cell chronic lymphocytic leukemia (CLL). We have used a limiting dilution (LD) culture approach to quantitatively assess frequencies of proliferating lymphocyte precursors (PLP), cytotoxic lymphocyte precursors (CLP), and interleukin-2 (IL-2)-producing helper lymphocyte precursors (HLP). Unseparated mononuclear cells (MNC) or purified T cells (E+) and leukemic B cells (E-) were cocultured under LD conditions with irradiated OKT3 hybridoma cells in the absence (determination of HLP) or presence of recombinant IL-2 (determination of PLP and CLP). Under these conditions, low frequencies of PLP, HLP, and CLP (f = 1/65 to 1/4600) were measured in unseparated MNC of CLL patients. In contrast, purified T cells (50% to 92% CD3+) contained precursors of proliferating, IL-2-producing and cytotoxic T cells in similar frequency as did T cells from healthy control donors (f = 1/4 to 1/24). Leukemic B cells rigorously depleted of T cells did not give rise to measurable frequencies of PLP, HLP, or CLP (f less than 1/50.000) except in one CLL patient where a significant frequency (f = 1/1700) of HLP was consistently present in E- cells, despite the absence of growth-inducible PLP and CLP. Taken together, these results indicate that comparable numbers of IL-2-producing helper T cells and cytotoxic T cells are present in B-CLL patients and healthy controls, respectively. The data are discussed with respect to reported T cell abnormalities in B-CLL.

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Defective T cell-mediated, isotype-specific immunoglobulin regulation in B cell chronic lymphocytic leukemia

Blood ◽

10.1182/blood.v71.4.1012.bloodjournal7141012 ◽

1988 ◽

Vol 71 (4) ◽

pp. 1012-1020 ◽

Cited By ~ 1

Author(s):

JS Moore ◽

MB Prystowsky ◽

RG Hoover ◽

EC Besa ◽

PC Nowell

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Cell Activity ◽

Lymphocytic Leukemia ◽

Specific Immunoglobulin ◽

Cell Chronic Lymphocytic Leukemia

The consistent occurrence of T cell abnormalities in patients with B cell chronic lymphocytic leukemia (B-CLL) suggest that the non- neoplastic host T cells may be involved in the pathogenesis of this B cell neoplasm. Because potential defects of immunoglobulin regulation are evident in B-CLL patients, we investigated one aspect of this by studying the T cell-mediated immunoglobulin isotype-specific immunoregulatory circuit in B-CLL. The existence of class-specific immunoglobulin regulatory mechanisms mediated by Fc receptor-bearing T cells (FcR + T) through soluble immunoglobulin binding factors (IgBFs) has been well established in many experimental systems. IgBFs can both suppress and enhance B cell activity in an isotype-specific manner. We investigated the apparently abnormal IgA regulation in a B-CLL patient (CLL249) whose B cells secrete primarily IgA in vitro. Enumeration of FcR + T cells showed a disproportionate increase in IgA FcR + T cells in the peripheral blood of this patient. Our studies showed that the neoplastic B cells were not intrinsically unresponsive to the suppressing component of IgABF produced from normal T cells, but rather the IgABF produced by the CLL249 host T cells was defective. CLL249 IgABF was unable to suppress IgA secretion by host or normal B cells and enhanced the in vitro proliferation of the host B cells. Size fractionation of both normal and CLL249 IgABF by gel-filtration high- performance liquid chromatography (HPLC) demonstrated differences in the ultraviolet-absorbing components of IgABF obtained from normal T cells v that from our patient with defective IgA regulation. Such T cell dysfunction may not be restricted to IgA regulation, since we have found similar expansion of isotype-specific FcR + T cells associated with expansion of the corresponding B cell clone in other patients with B-CLL. These data suggest that this T cell-mediated regulatory circuit could be significantly involved in the pathogenesis of B-CLL.

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Antigen presentation in an HLA-DR-restricted fashion by B-cell chronic lymphocytic leukemia cells

Blood ◽

10.1182/blood.v72.1.102.bloodjournal721102 ◽

1988 ◽

Vol 72 (1) ◽

pp. 102-108 ◽

Cited By ~ 7

Author(s):

M Yasukawa ◽

T Shiroguchi ◽

A Inatsuki ◽

Y Kobayashi

Keyword(s):

T Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Antigen Presentation ◽

Interleukin 2 ◽

Class Ii ◽

Hla Class Ii ◽

Lymphocytic Leukemia ◽

Hla Dr ◽

Cell Chronic Lymphocytic Leukemia

The ability of B-cell chronic lymphocytic leukemia (B-CLL) cells to present antigen to antigen-specific T cells was investigated. B-CLL cells present herpes simplex virus (HSV) antigen and purified protein derivative (PPD) to HSV- and PPD-specific, interleukin-2-dependent T- cell lines in an antigen-specific manner. Treatment of B-CLL cells with the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) induced markedly increased levels of HLA-DR expression. TPA-treated B-CLL cells showed substantially more effective presentation, especially at low antigen concentrations, than did untreated B-CLL cells. By coculturing different allogeneic combinations of B-CLL cells and T cells and by adding anti-HLA-DR monoclonal antibody to cultures, it was found that antigen presentation by B-CLL cells was restricted by HLA-DR in the same way as for macrophages. We concluded from these experiments that B- CLL cells have a capacity to serve as antigen-presenting cells in an HLA class II-restricted fashion and that increasing the amount of HLA class II antigen and activation of B-CLL cells resulted in effective antigen presentation.

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CD40-Activated B-Cell Chronic Lymphocytic Leukemia Cells for Tumor Immunotherapy: Stimulation of Allogeneic Versus Autologous T Cells Generates Different Types of Effector Cells

Blood ◽

10.1182/blood.v93.6.1992.406k23_1992_2002 ◽

1999 ◽

Vol 93 (6) ◽

pp. 1992-2002 ◽

Cited By ~ 113

Author(s):

Raymund Buhmann ◽

Annette Nolte ◽

Doreen Westhaus ◽

Bertold Emmerich ◽

Michael Hallek

Keyword(s):

T Cells ◽

T Cell ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Tumor Antigens ◽

Lymphocytic Leukemia ◽

T Cell Anergy ◽

Cell Anergy ◽

Cell Chronic Lymphocytic Leukemia ◽

Stimulation Of

Although spontaneous remissions may rarely occur in B-cell chronic lymphocytic leukemia (B-CLL), T cells do generally not develop a clinically significant response against B-CLL cells. Because this T-cell anergy against B-CLL cells may be caused by the inability of B-CLL cells to present tumor-antigens efficiently, we examined the possibility of upregulating critical costimulatory (B7-1 and B7-2) and adhesion molecules (ICAM-1 and LFA-3) on B-CLL cells to improve antigen presentation. The stimulation of B-CLL cells via CD40 by culture on CD40L expressing feeder cells induced a strong upregulation of costimulatory and adhesion molecules and turned the B-CLL cells into efficient antigen-presenting cells (APCs). CD40-activated B-CLL (CD40-CLL) cells stimulated the proliferation of both CD4+ and CD8+ T cells. Interestingly, stimulation of allogeneic versus autologous T cells resulted in the expansion of different effector populations. Allogeneic CD40-CLL cells allowed for the expansion of specific CD8+cytolytic T cells (CTL). In marked contrast, autologous CD40-CLL cells did not induce a relevant CTL response, but rather stimulated a CD4+, Th1-like T-cell population that expressed high levels of CD40L and released interferon-γ in response to stimulation by CD40-CLL cells. Together, these results support the view that CD40 activation of B-CLL cells might reverse T-cell anergy against the neoplastic cell clone, although the character of the immune response depends on the major histocompatibility complex (MHC) background on which the CLL or tumor antigens are presented. These findings may have important implications for the design of cellular immunotherapies for B-CLL.

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Superagonistic Anti-CD28 Antibody TGN1412 as a Potential Immunotherapeutic for the Treatment of B Cell Chronic Lymphocytic Leukemia.

Blood ◽

10.1182/blood.v104.11.2519.2519 ◽

2004 ◽

Vol 104 (11) ◽

pp. 2519-2519 ◽

Cited By ~ 1

Author(s):

Chia-Huey Lin ◽

Thomas Kerkau ◽

Christine Guntermann ◽

Martin Trischler ◽

Niklas Beyersdorf ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Mhc Class Ii ◽

T Cell Activation ◽

Lymphocytic Leukemia ◽

Leukemic Cells ◽

Activation Markers ◽

Cell Chronic Lymphocytic Leukemia

Abstract B cell chronic lymphocytic leukemia (B-CLL) is characterised by an accumulation of malignant B cells, and impaired humoral and cellular immune responses. Evasion strategies of leukemic cells appear to involve down-regulation of co-stimulatory molecules as well as increased resistance to apoptosis. Here we provide data supporting a novel concept to treat B-CLL with a humanized, superagonistic monoclonal antibody specific for CD28 (TGN1412). Superagonistic anti-CD28 antibodies have been shown to activate human T cells in vitro without requirement for engagement of the T cell antigen receptor (Luhder et al., J. Exp. Med. 2003. 197(8):955–66). Indicative of their activation, TGN1412-triggered T cells from healthy donors upregulate, among other activation markers, CD40L, that has been reported to promote anti-leukemic effects when ectopically expressed on B-CLL cells (Wierda et al., Blood. 2000. 96 (9): 2917–2924). In this report, the responses of PBMCs from B-CLL patients to soluble TGN1412 were examined. We show that in a dose-dependent fashion, polyclonal T cell activation was induced by TGN1412 including proliferation, cytokine production and induction of activation markers such as CD25, CD71, CD134 (Ox40), CTLA-4 (CD152) and CD154 (CD40L). Significantly, modulation of malignant B-CLL cells was also observed. MHC class II molecules (HLA-DR), CD95 and the co-stimulatory molecules CD80 and CD86, but not the proliferation marker Ki-67, were strongly up-regulated upon TGN1412 stimulation. These data suggested that improved antigen-presenting functions of B-CLL cells were induced by TGN1412. Accordingly, preliminary data indicate that B-CLL cells isolated from TGN1412 stimulated cultures induced enhanced proliferation of both allogeneic and autologous T cells, and importantly, TGN1412 activated T cells exhibited enhanced CTL-activity against B-CLL cells. In conclusion, our data suggest that TGN1412 induces polyclonal T cell expansion and activation as well as increased APC function of B-CLL cells. They imply that TGN1412 may have future therapeutic benefit for B-CLL patients.

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The Receptor for Hyaluronic Acid Mediated Motility (RHAMM/CD168) Is a Potential Target for Immunotherapy of Patients with B-Cell Chronic Lymphocytic Leukemia.

Blood ◽

10.1182/blood.v106.11.53.53 ◽

2005 ◽

Vol 106 (11) ◽

pp. 53-53 ◽

Cited By ~ 1

Author(s):

Krzysztof Giannopoulos ◽

Iwona Hus ◽

Li Li ◽

Agnieszka Bojarska-Junak ◽

Jochen Greiner ◽

...

Keyword(s):

T Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Mononuclear Cells ◽

Tissue Expression ◽

T Cell Response ◽

Lymphocytic Leukemia ◽

Leukemic Cells ◽

Peripheral Blood Mononuclear ◽

Cell Chronic Lymphocytic Leukemia

Abstract Definition of appropriate target antigens might open new avenues to antigen targeted immunotherapies for patients with B-cell chronic lymphocytic leukemia (B-CLL). We screened the mRNA expression of tumor associated antigens (TAAs), from the literature (fibromodulin, survivin, OFA-iLRP, BAGE, G250, MAGE1, PRAME, proteinase, Syntaxin, hTERT, WT-1), and TAAs defined earlier by serological analysis of cDNA expression libraries from leukemic cells (PINCH, HSJ2, MAZ, MPP11, RHAMM/CD168, NY-Ren60). Peripheral blood mononuclear cells from 43 B-CLL patients and 20 healthy volunteers (HVs) were examined by conventional and quantitative RT-PCR. mRNA of RHAMM/CD168, fibromodulin, syntaxin and NY-Ren60 was expressed in 55–90%, mRNA of HSJ2, MAZ and OFA-iLRP in 90–100% of the patients. No expression of WT-1, h-TERT, BAGE, G250, MAGE1 and survivin was observed. Low (2–20%) expression frequencies of MPP11, PINCH, PRAME and proteinase were detected. RHAMM/CD168, fibromodulin, PRAME and MPP11 showed expression in B-CLL patients, but not in HVs. Because of the exquisite tissue expression of RHAMM/CD168 and its high expression frequency in B-CLL patients even in early stages of disease, mixed lymphocyte peptide culture (MLPC), enzyme-linked immunosorbent spot (ELISPOT) and flow cytometry were performed for antigen specific T cells. In MLPC, RHAMM specific responses by CD8+HLA-A2/R3tetramer+CCR7-CD45RAhigh effector T cells were detected. Moreover, we observed an enhanced RHAMM/CD168 specific CD8+ T cell response after vaccination in one from four HLA-A2 positive B-CLL patients vaccinated with tumor cell lysate pulsed dendritic cells. Therefore, RHAMM/CD168 is an interesting candidate antigen for future immunotherapies in both ZAP-70 (+) and ZAP-70 (−) B-CLL patients.

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RHAMM/CD168 Is a Novel Leukemia Associated Antigen with Prognostic Value for Patients with B-Cell Chronic Lymphocytic Leukemia.

Blood ◽

10.1182/blood.v108.11.2773.2773 ◽

2006 ◽

Vol 108 (11) ◽

pp. 2773-2773

Author(s):

Krzysztof Giannopoulos ◽

Alexander Krober ◽

Anna Dmoszynska ◽

Jacek Rolinski ◽

Hartmut Dohner ◽

...

Keyword(s):

T Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Cd8 T Cells ◽

Mononuclear Cells ◽

Surrogate Marker ◽

Lymphocytic Leukemia ◽

Leukemic Cells ◽

Free Survival ◽

Cell Chronic Lymphocytic Leukemia

Abstract Background and Aims: Differential expression of molecules in patients with B-cell chronic lymphocytic leukemia (B-CLL) might define suitable targets for T cell based vaccines and/or antibody approaches. Methods: We assessed the mRNA expression of the tumor associated antigen (TAA) RHAMM/CD168 defined earlier by serological analysis of cDNA expression libraries (SEREX) from leukemic cells. Results: Peripheral blood mononuclear cells from 40 B-CLL patients and 20 healthy volunteers (HVs) were examined by quantitative RT-PCR. A leukemia-restricted expression of the antigen RHAMM/CD168 was observed in 39/40 B-CLL patients in contrast to the absence of its expression in HVs. To evaluate the immunogenicity of this novel LAA, mixed lymphocyte peptide cultures (MLPCs), followed by enzyme-linked immunosorbent spot (ELISPOT) and flow cytometry assays were performed to detect antigen-specific CD8+ T cells. RHAMM/CD168 specific responses by CD8+ HLA-A2/R3tetramer+CCR7-CD45RAhigh effector T cells were detected. As these CD8+ T cells contribute to the elimination of RHAMM+ CLL cells, we questioned whether expression of the antigen would be associated with a better survival. RHAMM/CD168 expression revealed to be higher in patients with unmutated IgVH status. RHAMM normalized against the housekeeping gene TATA binding protein (TBP), i.e. the RHAMM/TBP ratio was defined as a prognostic surrogate marker for B-CLL. B-CLL patients with a RHAMM/TBP ratio > 1.67 showed a significantly shorter treatment free survival (TFS) (Fig. 1). A tendency towards higher RHAMM/TBP expression ratios was observed in B-CLL cases with del11q. Conclusion: RHAMM/CD168 is a novel LAA in B-CLL patients, an antigen correlating with the clinical course of the disease. Therefore, we consider RHAMM/CD168 an interesting target for immunotherapy in early stage B-CLL patients, especially with worse prognosis (IgVH unmutated). Figure 1. Treatment-free-survival (TFS) according to RHAMM/TBP ratio Figure 1. Treatment-free-survival (TFS) according to RHAMM/TBP ratio

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Characterization of regulatory T cells in patients with B-cell chronic lymphocytic leukemia

Oncology Reports ◽

10.3892/or_00000059 ◽

1994 ◽

Cited By ~ 5

Author(s):

Giannopoulos

Keyword(s):

T Cells ◽

Chronic Lymphocytic Leukemia ◽

Regulatory T Cells ◽

B Cell ◽

Lymphocytic Leukemia ◽

Cell Chronic Lymphocytic Leukemia

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