1
|
Singh S, Banerjee S. Downregulation of HLA-ABC expression through promoter hypermethylation and downmodulation of MIC-A/B surface expression in LMP2A-positive epithelial carcinoma cell lines. Sci Rep 2020; 10:5415. [PMID: 32214110 PMCID: PMC7096436 DOI: 10.1038/s41598-020-62081-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 02/28/2020] [Indexed: 11/18/2022] Open
Abstract
Epstein Barr Virus (EBV) is a human herpesvirus, and has been reported to be associated with nasopharyngeal carcinoma, gastric carcinoma, Burkitt’s lymphoma and Hodgkin’s lymphoma. In most of the associated tumors, the virus remains in a latently infected state. During latency, EBV expresses Latent Membrane Protein 2A (LMP2A) along with few other genes. We previously showed that LMP2A causes downregulation of HLA-ABC surface expression in EBV associated gastric carcinomas. However, the mechanism that leads to this downregulation remain unclear. We therefore analyzed methylation-mediated regulation of HLA-ABC expression by LMP2A. Interestingly, according to the ‘missing self’ hypothesis, when there is a decrease in HLA-ABC surface expression, expression of NKG2D ligands’ must be upregulated to facilitate killing by Natural Killer (NK) cells. Analysis of NKG2D ligands’ expression, revealed downregulation of MIC-A/B surface expression in response to LMP2A. Furthermore, the role of Unfolded Protein Response (UPR) in the regulation of MIC-A/B surface expression in cells expressing LMP2A was also investigated. Protein Disulfide Isomerase (PDI) mediated inhibition of MIC-A/B surface expression was observed in LMP2A expressing cells. Our current findings provide new insights in LMP2A arbitrated dysregulation of host immune response in epithelial cell carcinomas.
Collapse
Affiliation(s)
- Shweta Singh
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Kolkata, India
| | - Subrata Banerjee
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Kolkata, India.
| |
Collapse
|
2
|
Grant M, Bollard CM. Developing T-cell therapies for lymphoma without receptor engineering. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2017; 2017:622-631. [PMID: 29222313 PMCID: PMC6142576 DOI: 10.1182/asheducation-2017.1.622] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
T-cell therapy has emerged from the bench for the treatment of patients with lymphoma. Responses to T-cell therapeutics are regulated by multiple factors, including the patient's immune system status and disease stage. Outside of engineering of chimeric antigen receptors and artificial T-cell receptors, T-cell therapy can be mediated by ex vivo expansion of antigen-specific T cells targeting viral and/or nonviral tumor-associated antigens. These approaches are contributing to enhanced clinical responses and overall survival. In this review, we summarize the available T-cell therapeutics beyond receptor engineering for the treatment of patients with lymphoma.
Collapse
Affiliation(s)
- Melanie Grant
- Center for Cancer and Immunology Research, Children’s National Health System, Washington, DC; and
| | - Catherine M. Bollard
- Center for Cancer and Immunology Research, Children’s National Health System, Washington, DC; and
- Departments of Pediatrics and Microbiology, Immunology, and Tropical Medicine, The George Washington University, Washington, DC
| |
Collapse
|
3
|
Developing T-cell therapies for lymphoma without receptor engineering. Blood Adv 2017; 1:2579-2590. [PMID: 29296911 DOI: 10.1182/bloodadvances.2017009886] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 09/14/2017] [Indexed: 12/19/2022] Open
Abstract
T-cell therapy has emerged from the bench for the treatment of patients with lymphoma. Responses to T-cell therapeutics are regulated by multiple factors, including the patient's immune system status and disease stage. Outside of engineering of chimeric antigen receptors and artificial T-cell receptors, T-cell therapy can be mediated by ex vivo expansion of antigen-specific T cells targeting viral and/or nonviral tumor-associated antigens. These approaches are contributing to enhanced clinical responses and overall survival. In this review, we summarize the available T-cell therapeutics beyond receptor engineering for the treatment of patients with lymphoma.
Collapse
|
4
|
Differential Recognition of Influenza A Viruses by M158-66 Epitope-Specific CD8+ T Cells Is Determined by Extraepitopic Amino Acid Residues. J Virol 2015; 90:1009-22. [PMID: 26537686 DOI: 10.1128/jvi.02439-15] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 10/29/2015] [Indexed: 12/13/2022] Open
Abstract
UNLABELLED Natural influenza A virus infections elicit both virus-specific antibody and CD4(+) and CD8(+) T cell responses. Influenza A virus-specific CD8(+) cytotoxic T lymphocytes (CTLs) contribute to clearance of influenza virus infections. Viral CTL epitopes can display variation, allowing influenza A viruses to evade recognition by epitope-specific CTLs. Due to functional constraints, some epitopes, like the immunodominant HLA-A*0201-restricted matrix protein 1 (M158-66) epitope, are highly conserved between influenza A viruses regardless of their subtype or host species of origin. We hypothesized that human influenza A viruses evade recognition of this epitope by impairing antigen processing and presentation by extraepitopic amino acid substitutions. Activation of specific T cells was used as an indication of antigen presentation. Here, we show that the M158-66 epitope in the M1 protein derived from human influenza A virus was poorly recognized compared to the M1 protein derived from avian influenza A virus. Furthermore, we demonstrate that naturally occurring variations at extraepitopic amino acid residues affect CD8(+) T cell recognition of the M158-66 epitope. These data indicate that human influenza A viruses can impair recognition by M158-66-specific CTLs while retaining the conserved amino acid sequence of the epitope, which may represent a yet-unknown immune evasion strategy for influenza A viruses. This difference in recognition may have implications for the viral replication kinetics in HLA-A*0201 individuals and spread of influenza A viruses in the human population. The findings may aid the rational design of universal influenza vaccines that aim at the induction of cross-reactive virus-specific CTL responses. IMPORTANCE Influenza viruses are an important cause of acute respiratory tract infections. Natural influenza A virus infections elicit both humoral and cellular immunity. CD8(+) cytotoxic T lymphocytes (CTLs) are directed predominantly against conserved internal proteins and confer cross-protection, even against influenza A viruses of various subtypes. In some CTL epitopes, mutations occur that allow influenza A viruses to evade recognition by CTLs. However, the immunodominant HLA-A*0201-restricted M158-66 epitope does not tolerate mutations without loss of viral fitness. Here, we describe naturally occurring variations in amino acid residues outside the M158-66 epitope that influence the recognition of the epitope. These results provide novel insights into the epidemiology of influenza A viruses and their pathogenicity and may aid rational design of vaccines that aim at the induction of CTL responses.
Collapse
|
5
|
Epstein-Barr virus latent membrane protein 2A mediated activation of Sonic Hedgehog pathway induces HLA class Ia downregulation in gastric cancer cells. Virology 2015; 484:22-32. [PMID: 26057149 DOI: 10.1016/j.virol.2015.05.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 05/05/2015] [Accepted: 05/11/2015] [Indexed: 12/12/2022]
Abstract
One of the immune evasion strategies manifested by malignant cells is the downregulation of the Human Leukocyte Antigen (HLA). HLA Class I (HLA- A, -B, -C) present endogenous peptides including viral and tumor antigens to cytotoxic T lymphocytes for immune mediated destruction. We have found the Epstein Barr Virus (EBV) Latent Membrane Protein 2A (LMP2A) to be responsible for this HLA downregulation in gastric cancer cells. Our results further indicate the Sonic Hedgehog pathway; primarily Gli1 to bring about the LMP2A mediated decrease in HLA expression.
Collapse
|
6
|
God JM, Zhao D, Cameron CA, Amria S, Bethard JR, Haque A. Disruption of HLA class II antigen presentation in Burkitt lymphoma: implication of a 47,000 MW acid labile protein in CD4+ T-cell recognition. Immunology 2014; 142:492-505. [PMID: 24628049 DOI: 10.1111/imm.12281] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 03/10/2014] [Accepted: 03/11/2014] [Indexed: 12/22/2022] Open
Abstract
While Burkitt lymphoma (BL) has a well-known defect in HLA class I-mediated antigen presentation, the exact role of BL-associated HLA class II in generating a poor CD4(+) T-cell response remains unresolved. Here, we found that BL cells are deficient in their ability to optimally stimulate CD4(+) T cells via the HLA class II pathway. This defect in CD4(+) T-cell recognition was not associated with low levels of co-stimulatory molecules on BL cells, as addition of external co-stimulation failed to elicit CD4(+) T-cell activation by BL. Further, the defect was not caused by faulty antigen/class II interaction, because antigenic peptides bound with measurable affinity to BL-associated class II molecules. Interestingly, functional class II-peptide complexes were formed at acidic pH 5·5, which restored immune recognition. Acidic buffer (pH 5·5) eluate from BL cells contained molecules that impaired class II-mediated antigen presentation and CD4(+) T-cell recognition. Biochemical analysis showed that these molecules were greater than 30,000 molecular weight in size, and proteinaceous in nature. In addition, BL was found to have decreased expression of a 47,000 molecular weight enolase-like molecule that enhances class II-mediated antigen presentation in B cells, macrophages and dendritic cells, but not in BL cells. These findings demonstrate that BL likely has multiple defects in HLA class II-mediated antigen presentation and immune recognition, which may be exploited for future immunotherapies.
Collapse
Affiliation(s)
- Jason M God
- Department of Microbiology and Immunology, Hollings Cancer Center, and Children's Research Institute, Medical University of South Carolina, Charleston, SC, USA
| | | | | | | | | | | |
Collapse
|
7
|
Destro F, Sforza F, Sicurella M, Marescotti D, Gallerani E, Baldisserotto A, Marastoni M, Gavioli R. Proteasome inhibitors induce the presentation of an Epstein-Barr virus nuclear antigen 1-derived cytotoxic T lymphocyte epitope in Burkitt's lymphoma cells. Immunology 2011; 133:105-14. [PMID: 21342184 DOI: 10.1111/j.1365-2567.2011.03416.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is generally expressed in all EBV-associated tumours and is therefore an interesting target for immunotherapy. However, evidence for the recognition and elimination of EBV-transformed and Burkitt's lymphoma (BL) cells by cytotoxic T lymphocytes (CTLs) specific for endogenously presented EBNA1-derived epitopes remains elusive. We confirm here that CTLs specific for the HLA-B35/B53-presented EBNA1-derived HPVGEADYFEY (HPV) epitope are detectable in the majority of HLA-B35 individuals, and recognize EBV-transformed B lymphocytes, thereby demonstrating that the GAr domain does not fully inhibit the class I presentation of the HPV epitope. In contrast, BL cells are not recognized by HPV-specific CTLs, suggesting that other mechanisms contribute to providing a full protection from EBNA1-specific CTL-mediated lysis. One of the major differences between BL cells and lymphoplastoid cell lines (LCLs) is the proteasome; indeed, proteasomes from BL cells demonstrate far lower chymotryptic and tryptic-like activities compared with proteasomes from LCLs. Hence, inefficient proteasomal processing is likely to be the main reason for the poor presentation of this epitope in BL cells. Interestingly, we show that treatments with proteasome inhibitors partially restore the capacity of BL cells to present the HPV epitope. This indicates that proteasomes from BL cells, although less efficient in degrading reference substrates than proteasomes from LCLs, are able to destroy the HPV epitope, which can, however, be generated and presented after partial inhibition of the proteasome. These findings suggest the use of proteasome inhibitors, alone or in combination with other drugs, as a strategy for the treatment of EBNA1-carrying tumours.
Collapse
Affiliation(s)
- Federica Destro
- Department of Biochemistry and Molecular Biology, University of Ferrara, Ferrara, Italy
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Burkitt lymphoma: pathogenesis and immune evasion. JOURNAL OF ONCOLOGY 2010; 2010. [PMID: 20953370 PMCID: PMC2952908 DOI: 10.1155/2010/516047] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 09/02/2010] [Indexed: 12/21/2022]
Abstract
B-cell lymphomas arise at distinct stages of cellular development and maturation, potentially influencing antigen (Ag) presentation and T-cell recognition. Burkitt lymphoma (BL) is a highly malignant B-cell tumor associated with Epstein-Barr Virus (EBV) infection. Although BL can be effectively treated in adults and children, leading to high survival rates, its ability to mask itself from the immune system makes BL an intriguing disease to study. In this paper, we will provide an overview of BL and its association with EBV and the c-myc oncogene. The contributions of EBV and c-myc to B-cell transformation, proliferation, or attenuation of cellular network and immune recognition or evasion will be summarized. We will also discuss the various pathways by which BL escapes immune detection by inhibiting both HLA class I- and II-mediated Ag presentation to T cells. Finally, we will provide an overview of recent developments suggesting the existence of BL-associated inhibitory molecules that may block HLA class II-mediated Ag presentation to CD4+ T cells, facilitating immune escape of BL.
Collapse
|
9
|
Rolén U, Freda E, Xie J, Pfirrmann T, Frisan T, Masucci MG. The ubiquitin C-terminal hydrolase UCH-L1 regulates B-cell proliferation and integrin activation. J Cell Mol Med 2010; 13:1666-1678. [PMID: 20187292 DOI: 10.1111/j.1582-4934.2008.00501.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The ubiquitin C-terminal hydrolase-L1 (UCH-L1) is a deubiquitinating enzyme that catalyses the hydrolysis of polyubiquitin precursors and small ubiquitin adducts. UCH-L1 has been detected in a variety of malignant and metastatic tumours but its biological function in these cells is unknown. We have previously shown that UCH-L1 is highly expressed in Burkitt's lymphoma (BL) and is up-regulated upon infection of B lymphocytes with Epstein-Barr virus (EBV). Here we show that knockdown of UCH-L1 by RNAi inhibits the proliferation of BL cells in suspension and semisolid agar and activates strong LFA-1-dependent homotypic adhesion. Induction of cell adhesion correlated with cation-induced binding to ICAM-1, clustering of LFA-1 into lipid rafts and constitutive activation of the Rap1 and Rac1 GTPases. Expression of a catalytically active UCH-L1 promoted the proliferation of a UCH-L1-negative EBV transformed lymphoblastoid cell line (LCL) and inhibited cell adhesion, whereas a catalytic mutant had no effect, confirming the requirement of UCH-L1 enzymatic activity for the regulation of these phenotypes. Our results identify UCH-L1 as a new player in the signalling pathways that promote the proliferation and invasive capacity of malignant B cells.
Collapse
Affiliation(s)
- Ulrika Rolén
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Elio Freda
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.,Current address: Department of Pediatrics, University of Rome, Tor Vergata, Rome, Italy
| | - Jianjun Xie
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.,Current address: Hematology Branch, Heart Lung and Blood Institute, Hatfield Clinical Research Center, NIH, Bethesda, MD, USA
| | - Thorsten Pfirrmann
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.,Current address: Wenner-Grens Institute for Cell Biology, Stockholm University, Stockholm, Sweden
| | - Teresa Frisan
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Maria G Masucci
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
10
|
Schlee M, Schuhmacher M, Hölzel M, Laux G, Bornkamm GW. c-MYC impairs immunogenicity of human B cells. Adv Cancer Res 2009; 97:167-88. [PMID: 17419945 DOI: 10.1016/s0065-230x(06)97007-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Deregulation of c-myc expression through chromosomal translocation is essential in the pathogenesis of Burkitt's lymphoma (BL). A characteristic feature of BL cells, compared to Epstein-Barr Virus (EBV)-immortalized B cells, is their lack of immunogenicity. To study the contribution of EBV genes and of the c-MYC protein to this phenotype, we have generated a conditional B cell system in which the viral proliferation program and expression of c-myc can be regulated independently of each other. In cells proliferating due to exogenous c-myc overexpression, the cell surface phenotype, the pattern of proliferation in single cell suspension, and the immunological characteristics of BL cells could be completely recapitulated. Yet, it had remained open whether nonimmunogenicity is the default phenotype when EBNA2 and LMP1 are switched off, or whether c-MYC actively contributes to immunosuppression. We provide evidence also for the latter by showing that c-MYC down-regulates genes of the NF-kappaB and interferon pathway in a dose-dependent fashion. c-MYC acts at at least two different levels, the level of interferon induction as well as at the level of action of type I and type II interferons on their respective target promoters. c-MYC does not block the interferon pathway completely, it shifts the balance and increases the threshold of interferon induction and action.
Collapse
Affiliation(s)
- Martin Schlee
- Institute of Clinical Molecular Biology and Tumor Genetics, GSF-National Research Center for Environment and Health, D-81377 München, Germany
| | | | | | | | | |
Collapse
|
11
|
Bornkamm GW. Epstein-Barr virus and the pathogenesis of Burkitt's lymphoma: more questions than answers. Int J Cancer 2009; 124:1745-55. [PMID: 19165855 DOI: 10.1002/ijc.24223] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Burkitt's lymphoma (BL) was first described as a clinical entity in children in Central Africa by Denis Burkitt in 1958. The particular epidemiological features of this tumor initiated the search for a virus as the causative agent and led to the discovery of Epstein-Barr virus (EBV) by Epstein and coworkers in 1964. It became apparent in the seventies and eighties that the tumor is not restricted to Central Africa, but occurs with lesser incidence all over the world (sporadic BL) and is also particularly frequent in HIV infected individuals, and that not all BL cases are associated with EBV: about 95% of the cases in Central Africa, 40 to 50% of the cases in HIV-infected individuals and 10 to 20% of the sporadic cases harbour the viral information and express at least one viral antigen (EBNA1) and a number of non-coding viral RNAs. In contrast, all BL cases regardless of their geographical origin exhibit one of three c-myc/Ig chromosomal translocations leading to the activation of the c-myc gene as a crucial event in the development of this disease. Although epidemiological evidence clearly points to a role of the virus in the African cases, the role of EBV in the pathogenesis of BL has remained largely elusive. This review summarizes current concepts and ideas how EBV might contribute to the development of BL in the light of the progress made in the last decade and discusses the problems of the experimental systems available to test such hypotheses.
Collapse
Affiliation(s)
- Georg W Bornkamm
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Clinical Molecular Biology and Tumor Genetics, München, Germany.
| |
Collapse
|
12
|
Gene expression predicts overall survival in paraffin-embedded tissues of diffuse large B-cell lymphoma treated with R-CHOP. Blood 2008; 112:3425-33. [PMID: 18544678 DOI: 10.1182/blood-2008-02-137372] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Gene expression profiling (GEP) on frozen tissues has identified genes predicting outcome in patients with diffuse large B-cell lymphoma (DLBCL). Confirmation of results in current patients is limited by availability of frozen samples and addition of monoclonal antibodies to treatment regimens. We used a quantitative nuclease protection assay (qNPA) to analyze formalin-fixed, paraffin-embedded tissue blocks for 36 previously identified genes (N = 209, 93 chemotherapy; 116 rituximab + chemotherapy). By qNPA, 208 cases were successfully analyzed (99.5%). In addition, 15 of 36 and 11 of 36 genes, representing each functional group previously identified by GEP, were associated with survival (P < .05) in the 2 treatment groups, respectively. In addition, 30 of 36 hazard ratios of death trended in the same direction versus the original studies. Multivariate and variable cut-off point analysis identified low levels of HLA-DRB (< 20%) and high levels of MYC (> 80%) as independent indicators of survival, together distinguishing cases with the worst prognosis. Our results solve a clinical research problem by demonstrating that prognostic genes can be meaningfully quantified using qNPA technology on formalin-fixed, paraffin-embedded tissues; previous GEP findings in DLBCL are relevant with current treatments; and 2 genes, representing immune escape and proliferation, are the common features of the most aggressive DLBCL.
Collapse
|
13
|
Schlee M, Hölzel M, Bernard S, Mailhammer R, Schuhmacher M, Reschke J, Eick D, Marinkovic D, Wirth T, Rosenwald A, Staudt LM, Eilers M, Baran-Marszak F, Fagard R, Feuillard J, Laux G, Bornkamm GW. C-myc activation impairs the NF-kappaB and the interferon response: implications for the pathogenesis of Burkitt's lymphoma. Int J Cancer 2007; 120:1387-95. [PMID: 17211884 DOI: 10.1002/ijc.22372] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Deregulation of the proto-oncogene c-myc is a key event in the pathogenesis of many tumors. A paradigm is the activation of the c-myc gene by chromosomal translocations in Burkitt lymphoma (BL). Despite expression of a restricted set of Epstein-Barr viral (EBV) antigens, BL cells are not recognized by antigen-specific cytotoxic T cells (CTLs) because of their inability to process and present HLA class I-restricted antigens. In contrast, cells of EBV-driven posttransplant lymphoproliferative disease (PTLD) are recognized and rejected by EBV-specific CTLs. It is not known whether the poor immunogenicity of BL cells is due to nonexpression of viral antigens, overexpression of c-myc, or both. To understand the basis for immune recognition and escape, we have compared the mRNA expression profiles of BL and EBV-immortalized cells (as PTLD model). Among the genes expressed at low level in BL cells, we have identified many genes involved in the NF-kappaB and interferon response that play a pivotal role in antigen presentation and immune recognition. Using a cell line in which EBNA2 and c-myc can be regulated at will, we show that c-MYC negatively regulates STAT1, the central player linking the Type-I and Type-II interferon response. Switching off c-myc expression leads to STAT1 induction through a direct and indirect mechanism involving induction of Type-I interferons. c-MYC thus masks an interferon-inducing activity in these cells. Our findings imply that immune escape of tumor cells is not only a matter of in vivo selection but may be additionally promoted by activation of a cellular oncogene.
Collapse
Affiliation(s)
- Martin Schlee
- Institute of Clinical Molecular Biology and Tumor Genetics, GSF-National Research Center for Environment and Health, München, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Luczyński W, Kowalczuk O, Iłendo E, Stasiak-Barmuta A, Krawczuk-Rybak M. Upregulation of antigen-processing machinery components at mRNA level in acute lymphoblastic leukemia cells after CD40 stimulation. Ann Hematol 2007; 86:339-45. [PMID: 17285277 DOI: 10.1007/s00277-007-0256-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Accepted: 01/10/2007] [Indexed: 11/30/2022]
Abstract
The development of immunotherapy in hematologic malignancies has been observed in the last few years. One of the approaches is the use of cancer vaccines based on leukemia-derived dendritic cells (DC). Recent studies from our laboratory and other laboratories have shown that CD40 stimulation improves leukemia cells immunogenicity and generates an antitumor immune response. The design of future cancer vaccines requires the knowledge concerning the function of dendritic cells including antigen processing. The aim of our present study was the assessment of antigen-processing machinery (APM) components in acute lymphoblastic leukemia (ALL) cells before and after CD40 stimulation at messenger RNA (mRNA) level. Twenty-five children with ALL were enrolled into the study. Leukemic cells were stimulated (or not) with CD40L and IL-4. Elements of the antigen-processing machinery (MB1, LMP2, LMP7, LMP10, TAP1, TAP2, calnexin, calreticulin, tapasin, ERp57, zeta, delta) were determined by real-time PCR technique. The expression of important costimulatory and adhesion molecules considered as DC markers (CD40, CD54, CD80, CD83, CD86) were determined at the mRNA (PCR) and protein (flow cytometry) levels. The following are the results of our study: (1) We noted an upregulation of all costimulatory and adhesion molecules at the mRNA and protein levels in ALL cells after the culture; (2) the significant rise in expression of nearly all APM components after CD40 stimulation was observed. This confirms specific stimulation of the antigen-processing system in ALL cells by CD40L. Future work should focus on the clinical significance of these findings for immunotherapy in leukemias.
Collapse
Affiliation(s)
- Włodzimierz Luczyński
- Department of Pediatric Oncology, Medical University of Białystok, Bialystok, Poland.
| | | | | | | | | |
Collapse
|
15
|
Guerreiro-Cacais AO, Uzunel M, Levitskaya J, Levitsky V. Inhibition of heavy chain and beta2-microglobulin synthesis as a mechanism of major histocompatibility complex class I downregulation during Epstein-Barr virus replication. J Virol 2006; 81:1390-400. [PMID: 17108039 PMCID: PMC1797541 DOI: 10.1128/jvi.01999-06] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The mechanisms of major histocompatibility complex (MHC) class I downregulation during Epstein-Barr virus (EBV) replication are not well characterized. Here we show that in several cell lines infected with a recombinant EBV strain encoding green fluorescent protein (GFP), the virus lytic cycle coincides with GFP expression, which thus can be used as a marker of virus replication. EBV replication resulted in downregulation of MHC class II and all classical MHC class I alleles independently of viral DNA synthesis or late gene expression. Although assembled MHC class I complexes, the total pool of heavy chains, and beta2-microglobulin (beta2m) were significantly downregulated, free class I heavy chains were stabilized at the surface of cells replicating EBV. Calnexin expression was increased in GFP+ cells, and calnexin and calreticulin accumulated at the cell surface that could contribute to the stabilization of class I heavy chains. Decreased expression levels of another chaperone, ERp57, and TAP2, a transporter associated with antigen processing and presentation, correlated with delayed kinetics of MHC class I maturation. Levels of both class I heavy chain and beta2m mRNA were reduced, and metabolic labeling experiments demonstrated a very low rate of class I heavy chain synthesis in lytically infected cells. MHC class I and MHC class II downregulation was mimicked by pharmacological inhibition of protein synthesis in latently infected cells. Our data suggest that although several mechanisms may contribute to MHC class I downregulation in the course of EBV replication, inhibition of MHC class I synthesis plays the primary role in the process.
Collapse
Affiliation(s)
- Andre Ortlieb Guerreiro-Cacais
- IRIS Center for Strategic Research, Department of Microbiology, Tumor and Cell Biology, Cancer Centrum Karolinska, Karolinska Institute, Stockholm, Sweden
| | | | | | | |
Collapse
|
16
|
Dutta N, Gupta A, Mazumder DNG, Banerjee S. Down-regulation of locus-specific human lymphocyte antigen class I expression in Epstein-Barr virus-associated gastric cancer: implication for viral-induced immune evasion. Cancer 2006; 106:1685-93. [PMID: 16541432 DOI: 10.1002/cncr.21784] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND To understand whether the association between Epstein-Barr Virus (EBV) and gastric cancer (GC) has any role in loss of surface expression of human lymphocyte antigen (HLA) class I, the authors analyzed locus-specific transcriptional expression of HLA-A, HLA-B, HLA-C, and HLA-E along with other HLA-associated molecules (beta2-microglobulin [beta2M], cellular latent membrane protein [LMP], and transporter associated with antigen presentation [TAP]) in EBV-associated, primary GC (EBVaGC) and EBV-negative GC (EBVnGC) tissues. METHODS Approximately 20 EBVaGC tissues and 40 EBVnGC tissues and their corresponding normal tissues were used in the study. The presence of EBV in GC was established by EBV-encoded small RNA in situ hybridization analysis and BamHI W polymerase chain reaction (PCR) analysis. Transcriptional expression of viral LMP2A and several HLA class I genes were analyzed by reverse transcriptase (RT)-PCR. Surface expression levels of HLA class I proteins in cancer samples along with their normal counterparts also were quantified by flow cytometry. RESULTS The RT-PCR data suggested selective down-regulation of the HLA-A/HLA-B locus along with over-expression of HLA-E transcripts in EBVaGC (P < .05). This was confirmed further by the flow-cytometric studies using antibodies to HLA-ABC and HLA-E. Among the accessory molecules, LMP7 transcript was down-regulated in a number of EBVaGC tissues compared with EBVnGC. CONCLUSIONS The current results suggested that the establishment of EBV latent infection in gastric tissues allows malignant cells to avoid the immune surveillance of both cytotoxic T-lymphocytes and natural killer cells by regulating the differential expression of HLA class I molecules.
Collapse
Affiliation(s)
- Nirmal Dutta
- Biophysics Division, Saha Institute of Nuclear Physics, Kolkata, India
| | | | | | | |
Collapse
|
17
|
Comoli P, Rooney C. Treatment of Epstein–Barr Virus Infections: Chemotherapy, Antiviral Therapy, and Immunotherapy. EPSTEIN-BARR VIRUS 2006. [DOI: 10.3109/9781420014280.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
18
|
Vitalis TZ, Zhang QJ, Alimonti J, Chen SS, Basha G, Moise A, Tiong J, Tian MM, Choi KB, Waterfield D, Jeffries A, Jefferies WA. Using the TAP component of the antigen-processing machinery as a molecular adjuvant. PLoS Pathog 2005; 1:e36. [PMID: 16389301 PMCID: PMC1323471 DOI: 10.1371/journal.ppat.0010036] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2005] [Accepted: 10/25/2005] [Indexed: 11/19/2022] Open
Abstract
We hypothesize that over-expression of transporters associated with antigen processing (TAP1 and TAP2), components of the major histocompatibility complex (MHC) class I antigen-processing pathway, enhances antigen-specific cytotoxic activity in response to viral infection. An expression system using recombinant vaccinia virus (VV) was used to over-express human TAP1 and TAP2 (VV-hTAP1,2) in normal mice. Mice coinfected with either vesicular stomatitis virus plus VV-hTAP1,2 or Sendai virus plus VV-hTAP1,2 increased cytotoxic lymphocyte (CTL) activity by at least 4-fold when compared to coinfections with a control vector, VV encoding the plasmid PJS-5. Coinfections with VV-hTAP1,2 increased virus-specific CTL precursors compared to control infections without VV-hTAP1,2. In an animal model of lethal viral challenge after vaccination, VV-hTAP1,2 provided protection against a lethal challenge of VV at doses 100-fold lower than control vector alone. Mechanistically, the total MHC class I antigen surface expression and the cross-presentation mechanism in spleen-derived dendritic cells was augmented by over-expression of TAP. Furthermore, VV-hTAP1,2 increases splenic TAP transport activity and endogenous antigen processing, thus rendering infected targets more susceptible to CTL recognition and subsequent killing. This is the first demonstration that over-expression of a component of the antigen-processing machinery increases endogenous antigen presentation and dendritic cell cross-presentation of exogenous antigens and may provide a novel and general approach for increasing immune responses against pathogens at low doses of vaccine inocula.
Collapse
Affiliation(s)
- Timothy Z Vitalis
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Qian-Jin Zhang
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Judie Alimonti
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Susan S Chen
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Genc Basha
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alex Moise
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jacqueline Tiong
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Mei Mei Tian
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kyung Bok Choi
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Douglas Waterfield
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Oral Biology, Faculty of Dentistry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andy Jeffries
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Wilfred A Jefferies
- The Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- * To whom correspondence should be addressed. E-mail:
| |
Collapse
|
19
|
Abstract
Epstein-Barr virus (EBV), a human herpesvirus associated with lymphoid and epithelial cell tumors, encodes several proteins that exploit the ubiquitin-proteasome system to regulate latency and allow the persistence of infected cells in immunocompetent hosts. Further modifications of ubiquitin-dependent proteolysis by activated cellular oncogenes contribute to malignant transformation. A detailed understanding of these processes may lead to the development of new therapeutic strategies for EBV-associated cancers.
Collapse
Affiliation(s)
- Maria G Masucci
- Microbiology and Tumor Biology Center, Karolinska Institutet, Box 280, S-171 77 Stockholm, Sweden.
| |
Collapse
|
20
|
Muris JJF, Meijer CJLM, Cillessen SAGM, Vos W, Kummer JA, Bladergroen BA, Bogman MJJT, MacKenzie MA, Jiwa NM, Siegenbeek van Heukelom LH, Ossenkoppele GJ, Oudejans JJ. Prognostic significance of activated cytotoxic T-lymphocytes in primary nodal diffuse large B-cell lymphomas. Leukemia 2003; 18:589-96. [PMID: 14712286 DOI: 10.1038/sj.leu.2403240] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Clinical outcome in diffuse large B-cell lymphoma (DLBCL) remains unpredictable, despite the identification of clinical prognostic parameters. Here, we investigated in pretreatment biopsies of 70 patients with DLBCL whether numbers of activated cytotoxic T-lymphocytes (CTLs), as determined by the percentage of CD3-positive lymphocytes with granzyme B (GrB) expression, have similar prognostic value as found earlier in Hodgkin's lymphoma and anaplastic large-cell lymphoma and whether loss of major histocompatibility complex (MHC)-I molecules or expression of the GrB antagonist protease inhibitor 9 (PI9) may explain immune escape from CTL-mediated cell death. Independent of the International Prognostic Index (IPI), the presence of >/=15% activated CTLs was strongly associated with failure to reach complete remission, with a poor progression-free and overall survival time. Downregulation of MHC-I light- and/or heavy-chain expression was found in 41% of interpretable cases and in 19 of 56 interpretable cases PI9 expression was detected. We conclude that a high percentage of activated CTLs is a strong, IPI independent, indicator for an unfavorable clinical outcome in patients with primary nodal DLBCL. Although in part of DLBCL expression of PI9 and loss of MHC-I expression was found, providing a possible immune-escape mechanism in these cases, no correlation with clinical outcome was found.
Collapse
MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Female
- Genes, MHC Class I/physiology
- Humans
- Lymph Nodes/immunology
- Lymph Nodes/pathology
- Lymphocyte Activation
- Lymphoma, B-Cell/immunology
- Lymphoma, B-Cell/pathology
- Lymphoma, B-Cell/therapy
- Lymphoma, Large B-Cell, Diffuse/immunology
- Lymphoma, Large B-Cell, Diffuse/pathology
- Lymphoma, Large B-Cell, Diffuse/therapy
- Male
- Microtubule Proteins
- Middle Aged
- Neoplasm Staging
- Phosphoproteins/metabolism
- Prognosis
- Stathmin
- Survival Rate
- T-Lymphocytes, Cytotoxic/immunology
- Treatment Outcome
Collapse
Affiliation(s)
- J J F Muris
- Department of Clinical Pathology, Vrije Universiteit Medical Center, Amsterdam, The Netherlands
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
|
22
|
Swaminathan S. Molecular biology of Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus. Semin Hematol 2003. [DOI: 10.1016/s0037-1963(03)70002-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
23
|
Gavioli R, Vertuani S, Masucci MG. Proteasome inhibitors reconstitute the presentation of cytotoxic T-cell epitopes in Epstein-Barr virus-associated tumors. Int J Cancer 2002; 101:532-8. [PMID: 12237893 DOI: 10.1002/ijc.10653] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
EBV-infected cells and EBV-associated tumors may evade CTL recognition by defective antigen processing, resulting in poor presentation of CTL epitopes. Since the proteasome is the major source of MHC class I-presented peptides, we analyzed the effect of proteasome inhibitors on the expression of surface HLA class I and the generation of EBV-derived CTL epitopes presented by the HLA-A2 and HLA-A11 alleles. Treatment with covalent and reversible inhibitors of the proteasome partially reduced the total and allele-specific expression of surface HLA class I in EBV-carrying LCLs. HLA-A2 expression was also decreased by treatment with leupeptin and bestatin, while HLA-A11 expression was affected by treatment with phenanthroline. Despite their general inhibitory effect on HLA class I expression, all proteasome inhibitors tested enhanced the presentation of 2 subdominant HLA-A2 epitopes from EBV LMP1 and LMP2, while the presentation of the immunodominant HLA-A11-restricted epitope from EBNA4 was inhibited by MG132 and lactacystin and increased by ZL(3)VS. Treatment with ZL(3)VS restored the presentation of endogenously expressed EBNA4 in 1 HLA-A11-positive BL cell line. These findings suggest that specific inhibitors of the proteasome may be used to increase the antigenicity of virus-infected and malignant cells that are per se inefficient at generating particular CTL target epitopes.
Collapse
Affiliation(s)
- Riccardo Gavioli
- Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden
| | | | | |
Collapse
|
24
|
Staege MS, Lee SP, Frisan T, Mautner J, Scholz S, Pajic A, Rickinson AB, Masucci MG, Polack A, Bornkamm GW. MYC overexpression imposes a nonimmunogenic phenotype on Epstein-Barr virus-infected B cells. Proc Natl Acad Sci U S A 2002; 99:4550-5. [PMID: 11917131 PMCID: PMC123685 DOI: 10.1073/pnas.072495599] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lymphoblastoid cell lines, generated by immortalization of normal B cells by Epstein-Barr virus (EBV) in vitro, have strong antigen-presenting capacity, are sensitive to EBV-specific cytotoxic T cells, and are highly allostimulatory in mixed lymphocyte culture. By contrast, EBV-positive Burkitt lymphoma (BL) cells are poor antigen presenters, are not recognized by EBV-specific cytotoxic T cells, and are poorly allostimulatory, which raises the question of whether immunological pressure exerted during BL pathogenesis in vivo has selected for a 'nonimmunogenic' tumor phenotype. The present work addresses this question by examining the immunogenicity/antigenicity of cell lines, generated by conversion of a conditionally immortalized lymphoblastoid cell line to permanent growth independent of EBV-latent proteins by introduction of a constitutively active or tetracycline-regulated c-myc gene (A1 and P493-6 cells, respectively). Compared with its parental lymphoblastoid cell line, A1 cells showed many of the features of the nonimmunogenic BL phenotype, namely poor allostimulatory activity, poor antigen-presenting function associated with impaired proteasomal activity, down-regulation of peptide transporter, reduced HLA class I expression, and an inability to present endogenously expressed EBV-latent proteins to cytotoxic T cells. P493-6 cells, when grown in the presence of estrogen with the exogenous c-myc gene switched off, were strongly immunogenic. The cells had lost their immunogenic potential, however, when grown on a c-myc-driven proliferation program in the absence of estrogen. Deregulation of c-myc, a step central to the development of uncontrolled BL cell growth in vivo, can thus impose a nonimmunogenic phenotype on proliferating human B cells in the absence of any immune pressure.
Collapse
Affiliation(s)
- Martin S Staege
- Institut für Klinische Molekularbiologie und Tumorgenetik, GSF-Forschungszentrum für Umwelt und Gesundheit, Marchioninistrasse 25, D-81377 München, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Addo MM, Rosenberg ES. Cellular immune responses in transplantation-associated chronic viral infections. Transpl Infect Dis 2002; 4:31-40. [PMID: 12123424 DOI: 10.1034/j.1399-3062.2002.00006.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Viral pathogens are important causes of morbidity following transplantation. Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections represent two major viral complications in transplant recipients. Recent advances in methodology have led to a better understanding of host immune responses directed against chronic viral infections. We review the nature of antiviral immunity involved in control of CMV and EBV. Viral mechanisms of immune evasion and immunotherapeutic strategies in the transplantation setting will also be addressed.
Collapse
Affiliation(s)
- M M Addo
- Partners AIDS Research Center, Massachusetts General Hospital, Chalestown, Massachussetts 02114, USA
| | | |
Collapse
|
26
|
Hallermalm K, Seki K, Wei C, Castelli C, Rivoltini L, Kiessling R, Levitskaya J. Tumor necrosis factor-alpha induces coordinated changes in major histocompatibility class I presentation pathway, resulting in increased stability of class I complexes at the cell surface. Blood 2001; 98:1108-15. [PMID: 11493458 DOI: 10.1182/blood.v98.4.1108] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It is demonstrated that similar to interferon gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha) induces coordinated changes at different steps of the major histocompatibility complex (MHC) class I processing and presentation pathway in nonprofessional antigen-presenting cells (APCs). TNF-alpha up-regulates the expression of 3 catalytic immunoproteasome subunits--LMP2, LMP7, and MECL-1--the immunomodulatory proteasome activator PA28 alpha, the TAP1/TAP2 heterodimer, and the total pool of MHC class I heavy chain. It was also found that in TNF-alpha--treated cells, MHC class I molecules reconstitute more rapidly and have an increased average half-life at the cell surface. Biochemical changes induced by TNF-alpha in the MHC class I pathway were translated into increased sensitivity of TNF-alpha--treated targets to lysis by CD8(+) cytotoxic T cells, demonstrating improved presentation of at least certain endogenously processed MHC class I--restricted peptide epitopes. Significantly, it was demonstrated that the effects of TNF-alpha observed in this experimental system were not mediated through the induction of IFN-gamma. It appears to be likely that TNF-alpha--mediated effects on MHC class I processing and presentation do not involve any intermediate messengers. Collectively, these data demonstrate the existence of yet another biologic activity exerted by TNF-alpha, namely its capacity to act as a coordinated multi-step modulator of the MHC class I pathway of antigen processing and presentation. These results suggest that TNF-alpha may be useful when a concerted up-regulation of the MHC class I presentation machinery is required but cannot be achieved by IFN-gamma. (Blood. 2001;98:1108-1115)
Collapse
Affiliation(s)
- K Hallermalm
- Cancer Centrum Karolinska, Karolinska Institutet, Stockholm, Sweden
| | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus that is associated with a variety of malignancies. In vivo infection of B lymphocytes is initially associated with the broad expression of immunodominant viral latency genes and proliferation of infected cells. Ultimately, a viral reservoir is established in resting B cells with restricted expression of viral latency genes and no expression of immunodominant viral genes. Among the tumours associated with EBV that are relevant to a consideration of EBV in HIV-associated malignancies are posttransplant lymphoproliferative disease, Burkitt's lymphoma (BL) and Hodgkin's disease (HD). BL carries whereas EBV in only a minority of cases whereas HD in patients infected with HIV is virtually always EBV-associated. EBV-directed T cell therapies have proven effective in posttransplant lymphomas in bone marrow transplantation patients. In patients with HIV infection, primary central nervous system (CNS) and immunoblastic lymphomas show similarities with posttransplant lymphoproliferative disease. EBV detection studies in cerebrospinal fluid are useful diagnostically in primary CNS lymphoma. T cell therapies may be useful in the treatment of EBV-associated lymphomas. Thus, a better understanding of the relationship between EBV and these tumours will not only help to clarify their pathogenesis, but may facilitate the development of new diagnostic and therapeutic strategies.
Collapse
Affiliation(s)
- R F Ambinder
- Division of Hematologic Malignancies, Department of Oncology, and Viral Oncology Program, Comprehensive Cancer Center, Johns Hopkins University School of Medicine, 1650 Orleans Street, Baltimore, MD 21231, USA.
| |
Collapse
|
28
|
Zhang QJ, Chen SS, Saari CA, Massuci MG, Tufaro F, Jefferies WA. Evidence of selective processing of immunodominant epitopes in virally infected cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:4513-21. [PMID: 10779752 DOI: 10.4049/jimmunol.164.9.4513] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recent advances in clarifying the molecular mechanisms involved in Ag processing and presentation have relied heavily on the use of somatic cell mutants deficient in proteasome subunits, TAP transporter, and cell surface expression of MHC class I molecules. Of particular interest currently are those mutants that lack specific protease activity involved in the generation of antigenic peptides. It is theoretically possible that deficiencies of this nature could selectively prevent the cleavage of certain peptide bonds and thus generate only a subset of antigenic peptides. Gro29/Kb cell line is derived from the wild-type murine Ltk- cell line. This cell line is one example of a mutant that lacks specific protease activities. This deficiency manifests itself in an inability to generate a subset of immunodominant peptide epitopes derived from vesicular stomatitis virus and herpes simplex virus. This in turn leads to a general inability to present these viral epitopes to cytotoxic T lymphocytes (CTL). These studies describe a unique Ag processing deficiency and provide new insight into the role of proteasome-independent proteases in MHC class I-restricted peptide generation.
Collapse
Affiliation(s)
- Q J Zhang
- Biotechnology Laboratory and Biomedical Research Centre, Medical Genetics and Zoology, University of British Columbia, Vancouver, Canada
| | | | | | | | | | | |
Collapse
|
29
|
Frisan T, Donati D, Cervenak L, Wilson J, Masucci MG, Bejarano MT. CD40 cross-linking enhances the immunogenicity of Burkitt's-lymphoma cell lines. Int J Cancer 1999; 83:772-9. [PMID: 10597194 DOI: 10.1002/(sici)1097-0215(19991210)83:6<772::aid-ijc13>3.0.co;2-g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Epstein-Barr-virus (EBV)-positive Burkitt's-lymphoma (BL) cell lines are not recognized by EBV-specific T cells, due to their non-immunogenic phenotype and restricted expression of latent EBV genes. We tested whether triggering of CD40 can alter the phenotype of the tumor cells with regard to: (i) expression of surface markers, (ii) expression of viral antigens, (iii) presentation of endogenous antigens to MHC-class-1 restricted cytotoxic T lymphocytes (CTLs), (iv) stimulatory capacity in allogeneic mixed-lymphocyte cultures (MLCs), (v) sensitivity to natural-killer (NK)-cell-mediated lysis. Co-culture of EBV-positive BL cells with CD40-ligand-transfected L cells induced up-regulation of CD54 and CD80 but did not affect the expression of viral genes. In spite of significant up-regulation of TAP1 and TAP2, and increased expression of MHC class 1, the BL cells remained unable to present endogenously expressed viral antigens to EBV-specific CTL. However, the up-regulation of adhesion and co-stimulatory molecules was associated with increased stimulatory capacity in MLC and enhanced sensitivity to NK cells. These findings indicate that, while inducing only a modest phenotype shift, cross-linking of CD40 under physiologic conditions may selectively enhance the sensitivity of BL cells to anti-tumor immune responses.
Collapse
MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 2
- ATP Binding Cassette Transporter, Subfamily B, Member 3
- ATP-Binding Cassette Transporters/genetics
- Antigens, CD/immunology
- Burkitt Lymphoma/immunology
- CD40 Antigens/immunology
- Cross-Linking Reagents
- Cysteine Endopeptidases/genetics
- Cytotoxicity, Immunologic
- Gene Expression Regulation, Neoplastic
- Gene Expression Regulation, Viral
- Herpesvirus 4, Human/genetics
- Herpesvirus 4, Human/immunology
- Histocompatibility Antigens Class I/genetics
- Humans
- Killer Cells, Natural/immunology
- Ligands
- Multienzyme Complexes/genetics
- Proteasome Endopeptidase Complex
Collapse
Affiliation(s)
- T Frisan
- Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden
| | | | | | | | | | | |
Collapse
|
30
|
Avoiding Immunity and Apoptosis: Manipulation of the Host Environment by Herpes Simplex Virus and Epstein-Barr Virus. ACTA ACUST UNITED AC 1998. [DOI: 10.1006/smvy.1997.0144] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
31
|
Frisan T, Levitsky V, Polack A, Masucci MG. Phenotype-Dependent Differences in Proteasome Subunit Composition and Cleavage Specificity in B Cell Lines. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.160.7.3281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
We have compared the subunit composition and enzymatic activity of purified 26S proteasomes from Burkitt’s lymphoma (BL) cells and in vitro EBV-transformed lymphoblastoid cell lines (LCLs) of normal B cell origin. Low expression of the IFN-γ-regulated β low molecular mass polypeptide (Lmp)2, Lmp7, and MECL-1 was demonstrated in a panel of seven BL lines that express the germinal center cell phenotype of the original tumor. Coexpression of Lmp2 and Lmp7 with the constitutively expressed subunits δ and MB1 was demonstrated in the BL lines by immunoprecipitation and two-dimensional gel fractionation of the 20S proteasomes. Coexpression of these subunits correlated with reduced levels of chymotrypsin- and trypsin-like activities detected by the cleavage of fluorogenic substrates. Down-regulation of Lmp2 and Lmp7 and decreased chymotrypsin- and trypsin-like activities were also observed in purified proteasomes from a c-myc-transfected subline of the ER/EB2–5 LCL that has adopted a BL-like phenotype. A synthetic peptide analogue of the immunodominant epitope from the EBV nuclear Ag 4 (E4416–424Y) was cleaved by proteasomes from BLs and A1, while proteasomes from LCLs were inactive. Cleavage of the E4416–424Y peptide was not affected by treatment of the BL cells with IFN-γ despite both significant up-regulation of Lmp2 and Lmp7 and reconstitution of chymotrypsin and trypsin-like activities against fluorogenic substrates to LCL-like levels. The results demonstrate that B cell lines representing different stages of B cell activation and differentiation express proteasomes with different subunit compositions and enzymatic activity. This may result in the generation of a distinct set of endogenous peptides and influence the immunogenicity of these cells.
Collapse
Affiliation(s)
- Teresa Frisan
- *Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden; and
| | - Victor Levitsky
- *Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden; and
| | - Axel Polack
- †Istitut für Klinische Molekularbiologie und Tumorgenetik, Gesellschaft für Strahlung und Umweltforschung-Forschungszentrum für Umwelt und Gesundheit, Munich, Germany
| | - Maria G. Masucci
- *Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden; and
| |
Collapse
|
32
|
Mukherjee S, Trivedi P, Dorfman DM, Klein G, Townsend A. Murine cytotoxic T lymphocytes recognize an epitope in an EBNA-1 fragment, but fail to lyse EBNA-1-expressing mouse cells. J Exp Med 1998; 187:445-50. [PMID: 9449725 PMCID: PMC2212114 DOI: 10.1084/jem.187.3.445] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Major histocompatibility complex class I-restricted cytotoxic T lymphocytes (CTLs) specific for epitopes within eight of the nine Epstein Barr Virus (EBV)-encoded latency-associated proteins have been recovered from EBV-infected human subjects by restimulation of lymphocytes in vitro. However, human class I-restricted CTL responses capable of recognizing EBNA-1 expressing cells were not detected in these studies. We have raised a murine CTL line that recognizes an epitope within EBNA-1 by immunizing mice with a vaccinia virus encoding a COOH-terminal EBNA-1 fragment. This novel CTL line was used to investigate whether the epitope (positions 509-517 in EBNA-1, presented through Kd) was presented to CTL by mouse cells expressing full-length EBNA-1 or a deletion mutant of EBNA-1, lacking the Glycine-Alanine (Gly-Ala)-rich region. Cells expressing full-length EBNA-1 are not lysed by the CTL line, whereas cells expressing the Gly-Ala deletion mutant are recognized. These results suggest that epitopes from full-length EBNA-1 are poorly presented, and that the Gly-Ala-rich region is responsible for this phenomenon. The inefficient presentation of EBNA-1-derived epitopes may explain the absence or rarity of EBNA-1-specific CTLs in vivo, a strategy that may allow EBV to maintain persistence within the immunocompetent host without being eliminated by CTLs.
Collapse
Affiliation(s)
- S Mukherjee
- Molecular Immunology Group, Institute for Molecular Medicine, John Radcliffe Hospital, Headington, Oxford, OX39DU, United Kingdom
| | | | | | | | | |
Collapse
|
33
|
Abstract
Respiratory infection of BALB/c mice with the murine gammaherpesvirus 68 (MHV-68) induces the clonal expansion of virus-specific cytotoxic T-lymphocyte (CTL) precursors (CTLp) in the regional, mediastinal lymph nodes (MLN). Some of these CTLps differentiate to become fully functional CTL effectors, which can be detected in both the lymphoid tissue and in the site of pathology in the lung. Though the lymph nodes and spleen harbor substantial populations of latently infected B cells for life, the level of virus-specific CTL activity decreases rapidly in all sites. The CD8+ CTLp numbers fall to background levels in the MLN within several months of the termination of the productive phase of MHV-68 infection in the respiratory epithelium but are maintained at relatively low frequency in the spleen. The continued presence of a gamma interferon-producing, MHV-68-specific CD4+ set can also be demonstrated in cultured spleen cells. The virus-specific immunoglobulin G (IgG) response is slow to develop, with serum neutralizing antibody and enzyme-linked immunosorbent assay titers continuing to rise for several months. The level of total serum IgG increases dramatically within 2 weeks of infection, probably as a consequence of polyclonal B-cell activation, and remains high. The immune response profile is clearly influenced by the persistence of this DNA virus.
Collapse
Affiliation(s)
- P G Stevenson
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
| | | |
Collapse
|
34
|
Ben-Shahar S, Cassouto B, Novak L, Porgador A, Reiss Y. Production of a specific major histocompatibility complex class I-restricted epitope by ubiquitin-dependent degradation of modified ovalbumin in lymphocyte lysate. J Biol Chem 1997; 272:21060-6. [PMID: 9261108 DOI: 10.1074/jbc.272.34.21060] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Peptide epitopes presented through class I major histocompatability complex (MHC class I) on the cell surface, are generated by proteolytic processing of protein-antigens in the cytoplasm. The length and amino acid sequence determine whether a given peptide can fit into the peptide binding groove of class I heavy chain molecules and subsequently be presented to the immune system. The mode of action of the processing pathway is therefore of great interest. To study the processing mechanism of MHC class I-restricted intracellular antigens, we reconstituted the proteolytic processing of a model antigen in a cell-free system. Incubation of oxidized and urea-treated OVA in lymphocyte lysate resulted in partial degradation of the antigen. Degradation of the antigen depended on the presence of ATP. Addition of methylated ubiquitin abolished the reaction which was then restored by addition of an excess of native ubiquitin, indicating that the breakdown of the antigen in lymphocyte lysate is mediated by the ubiquitin proteolytic system. Upon incubation of modified OVA in lymphocyte lysate, a specific antigenic peptide was generated. The peptide was recognized by cytotoxic T lymphocytes directed against OVA-derived, H-2Kb-restricted peptide (SIINFEKL), and by a monoclonal antibody that recognizes cell-bound Kb-SIINFEKL complexes. Formation of the peptide epitope depended on the presence of ATP and ubiquitin. These results indicate that proteolytic processing of modified OVA is carried out by the ubiquitin-mediated degradation system. The experimental system described provides a tool to analyze the molecular mechanisms underlying the generation of specific, MHC class I-restricted peptide epitopes.
Collapse
Affiliation(s)
- S Ben-Shahar
- Department of Biochemistry, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | | | | | | | | |
Collapse
|