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In Patients with Multiple Sclerosis CD8+ T Cell-Mediated HLA-A*0201-Restricted Cytotoxicity to Transaldolase Peptide 168 −176 in Patients with Multiple Sclerosis This information is current as Brian Niland, Katalin Banki, William E. Biddison and Andras of October 7, 2021. Perl J Immunol 2005; 175:8365-8378; ; doi: 10.4049/jimmunol.175.12.8365 http://www.jimmunol.org/content/175/12/8365 Downloaded from References This article cites 55 articles, 24 of which you can access for free at: http://www.jimmunol.org/content/175/12/8365.full#ref-list-1 Why The JI? Submit online. http://www.jimmunol.org/ • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication *average by guest on October 7, 2021 Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 2005 by The American Association of Immunologists All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. The Journal of Immunology CD8؉ T Cell-Mediated HLA-A*0201-Restricted Cytotoxicity to Transaldolase Peptide 168–176 in Patients with Multiple Sclerosis1 Brian Niland,*‡ Katalin Banki,*† William E. Biddison,§ and Andras Perl2*‡ Transaldolase (TAL) is expressed at selectively high levels in oligodendrocytes and targeted by autoreactive T cells of patients with multiple sclerosis (MS). Among 14 TAL peptides with predicted HLA-A2 binding, TAL 168–176 (LLFSFAQAV, TALpep) ex- hibited high affinity for HLA-A2. Prevalence of HLA-A2-restricted CD8؉ T cells specific for TALpep was increased in PBMC of HLA-A2؉ MS patients, as compared with HLA-A2؊ MS patients, HLA-A2؉ other neurological disease patients, and HLA-A2؉ healthy donors. HLA-A*0201/TALpep tetramers detected increased frequency of TAL-specific CD8؉ T cells, and precursor frequency of TAL-specific IFN-␥-producing T cells was increased in each of seven HLA-A2؉ MS patients tested. Stimulation by ؉ TALpep or rTAL of PBMC from HLA-A2 MS patients elicited killing of TALpep-pulsed HLA-A2-transfected HmyA2.1 lym- Downloaded from phoma cells, but not HLA-A3-transfected control HmyA3.1 targets. Without peptide pulsing of targets, HLA-A2-transfected, but not control MO3.13 oligodendroglial cells, expressing high levels of endogenous TAL, were also killed by CD8؉ CTL of MS patients, indicating recognition of endogenously processed TAL. TCR V␤ repertoire analysis revealed use of the TCR V␤14 gene by T cell lines (TCL) of MS patients generated via stimulation by TAL- or TALpep-pulsed APCs. All TAL-specific TCL-binding HLA-A*0201/TALpep tetramers expressed TCR V␤14 on the cell surface. Moreover, Ab to TCR V␤14 abrogated cytotoxicity by HLA-A2-restricted TAL-specific TCL. Therefore, TAL-specific CTL may serve as a novel target for therapeutic intervention in http://www.jimmunol.org/ patients with MS. The Journal of Immunology, 2005, 175: 8365–8378. ultiple sclerosis (MS)3 is considered to be an autoim- relapsing EAE have shown that different encephalitogenic mole- mune disease leading to progressive loss of oligoden- cules or epitopes within them are selected that are compatible with drocytes and demyelination in the CNS. In the acute the heterogeneity of the immune response in MS, suggesting that M ϩ ϩ stage of disease, lesions contain macrophages, CD4 and CD8 T disease initiation and relapse episodes are induced by different Ags cells, and Ig deposits, suggesting that the demyelination process is (13, 14). Although cell-mediated mechanisms may have a primary mediated by the immune system (1–4). The inflammatory picture role in EAE, augmentation of humoral immunity within the CNS by guest on October 7, 2021 of early lesions, which is followed by a progressive gliosis, also is a well-recognized feature of MS (15). A breakdown of the suggested that the pathological process may be initiated by infec- blood-brain barrier would allow Abs to enter the CNS and cause tious agents and then self-perpetuated by a cross-reactive autoim- demyelination by complement activation. In fact, complement may mune process (5–10). Although the Ag(s) driving this self-destruc- be directly involved in death of oligodendrocytes (16). Most efforts tive process in MS has not been identified (11), the importance of have been focused on myelin basic protein (MBP) and proteolipid myelin-derived Ags was demonstrated by their abilities to elicit an protein that make up as much as 30 and 50% of CNS myelin, MS-like demyelinating disease, experimental allergic encephalo- respectively (17, 18). T cell responses to MBP and proteolipid myelitis (EAE), in various animal models (12). protein, or another oligodendrocyte-specific protein myelin oligo- The major difficulties in applying the EAE model to MS stem dendrocyte protein (MOG), did not differ considerably between from a lack of identification of relevant autoantigen(s). Studies on MS patients and control donors (11). Although oral vaccination with a predefined inducing Ag may successfully prevent and treat disease in animal models (19), a similar approach with MBP in 30 *Department of Medicine, †Department of Pathology, and ‡Department of Microbi- ology and Immunology, State University of New York, College of Medicine, Syra- patients with MS led to no significant clinical improvement (20). cuse, NY 13210; and §Neuroimmunology Branch, National Institute of Neurological Molecular mimicry, i.e., cross-reactivity between self Ags and Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 viral proteins, has been implicated in the initiation of autoimmu- Received for publication August 5, 2005. Accepted for publication September nity and MS. Based on homology to retroviral sequences, a novel 26, 2005. autoantigen, partially encoded by a retrotransposon and selectively The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance expressed in oligodendrocytes at high levels (21), was identified as with 18 U.S.C. Section 1734 solely to indicate this fact. human transaldolase (TAL) (22). TAL is a key enzyme of the 1 This work was supported in part by Grants RO1 DK 49221 from the National pentose phosphate pathway (PPP). Although glucose is largely me- Institutes of Health and RG 2466 from the National Multiple Sclerosis Society. tabolized through the glycolytic pathway and the tricarboxylic acid 2 Address correspondence and reprint requests to Dr. Andras Perl, Department of cycle, the significance of PPP in the brain has long been estab- Medicine, State University of New York, 750 East Adams Street, Syracuse, NY 13210. E-mail address: [email protected] lished. During brain development, PPP provides NADPH for the biosynthesis of lipids (23). The latter is particularly important at 3 Abbreviations used in this paper: MS, multiple sclerosis; AEC, 3-amino-9-ethyl- ␤ ␤ carbazole; 2m, 2-microglobulin; EAE, experimental allergic encephalomyelitis; the period of active myelination (24, 25). The overall activity of 125 ␤ 125 ␤ FSC, forward scatter; HC, healthy control; I- 2m, I-labeled 2m; MBP, myelin PPP in the brain declines 5-fold from birth to maturity (26). Al- basic protein; MOG, myelin oligodendrocyte protein; MS, multiple sclerosis; OND, other neurological disease; PPP, pentose phosphate pathway; SSC, side scatter; TAL, though under normal conditions only as little as 1% of the glucose transaldolase; TALpep, TAL peptide 168–176; TCL, T cell line. enters the PPP (27), at times of rapid myelination up to 60% of the Copyright © 2005 by The American Association of Immunologists, Inc. 0022-1767/05/$02.00 8366 TAL-SPECIFIC CD8ϩ T CELL CYTOTOXICITY IN MS glucose is metabolized via the PPP (28). Involvement of PPP in TAL- or TALpep-pulsed APC derived from autologous PBMC or myelination provided a physiological explanation for the high EBV-transformed B cells expressed TCR V␤14 on their cell sur- level of TAL in oligodendrocytes (21–29). PPP also plays an es- face. Pretreatment of TCL lines with TCR V␤14 mAb abrogated sential role in neutralization of oxygen radicals, and elevated levels their cytotoxicity against HLA-A2-transfected Hmy A2.1 or of TAL expression increase susceptibility to apoptosis signals MO3.13 cells, suggesting that TAL-specific CTL may serve as a (30–32). Effector phase of the demyelination process in MS is therapeutic target to prevent oligodendrocyte destruction in pa- thought to be mediated by reactive oxygen intermediates. Intrale- tients with MS. sional CTLs produce TNF-␤, which, in turn, induces apoptosis, an oxidative stress-mediated programmed cell death, of oligodendro- Materials and Methods cytes (33). The Fas receptor/ligand system has also been impli- Patient and control cells cated in death of oligodendrocytes (34, 35). Thus, oligodendro- Fourteen patients with MS, eight patients with OND, and eight HC donors cyte-specific expression of TAL is possibly linked to production of were investigated (Table I). Patients with MS were diagnosed according to large amounts of lipids, as a major component of myelin and vul- the criteria of Poser et al. (42). PBMC were isolated from heparinized nerability of the vast network of myelin sheaths to oxygen radicals. venous blood on Ficoll-Hypaque gradient and resuspended in RPMI 1640 Immunohistochemical studies of postmortem brain sections re- medium supplemented with 10% heat-inactivated FBS, 2 mM L-glutamine, 100 U/ml penicillin, 100 ␮g/ml streptomycin, and 0.25 mg/ml amphoter- vealed decreased staining by MBP- and TAL-specific Abs in MS icin B, and cultured in a humidified atmosphere with 5% CO2 at 37°C.
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