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Related Collections Immunobiology Social Bookmarking                   What's this?  Previous Article  |  Table of Contents  |  Next Article  Blood, Vol. 95 No. 7 (April 1), 2000: pp. 2352-2355 IMMUNOBIOLOGY Granule exocytosis, and not the Fas/Fas ligand system, is the main pathway of cytotoxicity mediated by alloantigen-specific CD4+ as well as CD8+ cytotoxic T lymphocytes in humans Masaki Yasukawa, Hideki Ohminami, Junko Arai, Yoshihito Kasahara, Yasushi Ishida, and Shigeru Fujita From the First Department of Internal Medicine, Ehime University School of Medicine, Shigenobu, Ehime; Department of Pediatrics, Kanazawa University School of Medicine, Kanazawa, Ishikawa; and Department of Pediatrics, Ehime Prefectural Central Hospital, Matsuyama, Ehime, Japan.     Abstract Top Abstract Introduction Materials and methods Results Discussion References We investigated the cytotoxicity mechanisms of alloantigen-specific human CD4+ and CD8+ cytotoxic T lymphocytes (CTLs) using cells from family members with the Fas gene mutation. Alloantigen-specific CD4+ and CD8+ CTL bulk lines and clones were generated from 2 individuals by stimulation of their peripheral blood lymphocytes with allogeneic Fas/ or Fas+/ cell lines that were established from B-lymphocytes of a patient with Fas deficiency and her mother, respectively. Both CD4+ and CD8+ CTL bulk lines and clones directed against allogeneic HLA antigens exerted cytotoxicity against Fas/ and Fas+/ cells to almost the same degree. The cytotoxicity of CD4+ and CD8+ CTLs appeared to be Ca2+-dependent and was completely inhibited by concanamycin A, an inhibitor of perforin-mediated cytotoxicity. Messenger RNAs for the major mediators of CTL cytotoxicity, Fas ligand, perforin, and granzyme B were all detected in these CD4+ CTLs with the use of the reverse transcriptase polymerase chain reaction. The majority of CD4+ CTL clones that showed Fas-independent cytotoxicity were TH0, as determined by their cytokine production profile. These data, obtained with the use of a novel experimental system, clearly show that the main pathway of cytotoxicity mediated by alloantigen-specific human CD4+ as well as by CD8+ CTLs is granule exocytosis, and not the Fas/Fas ligand system. (Blood. 2000;95:2352-2355) © 2000 by The American Society of Hematology.     Introduction Top Abstract Introduction Materials and methods Results Discussion References There is no doubt that cytotoxic T lymphocytes (CTLs) directed against alloantigens play crucial roles in the development of graft rejection and graft-versus-host disease (GVHD) following organ transplantation. Therefore, understanding the cytotoxicity mechanisms of alloantigen-specific CTLs is essential in order to develop effective means of preventing rejection and GVHD. Two main pathways in CTL-mediated cytotoxicity, ie, granule exocytosis mediated by perforin/granzymes and the Fas/Fas ligand system, have been identified.1,2 The molecular mechanisms of CTL-mediated cytotoxicity have been studied extensively in murine systems with the use of various kinds of mutant and knockout mice, including Fas-mutant lpr,3 Fas ligand-mutant gld,4 perforin-deficient,5-8 and granzyme-deficient9 mice. These investigations have shown that CD8+ murine CTLs exert cytotoxicity mainly via granule exocytosis, whereas the main pathway of CD4+ murine CTL-mediated cytotoxicity is the Fas/Fas ligand system.10,11 In contrast to these recent advances in our understanding of the mechanisms of murine CTL-mediated cytotoxicity, the details of human CTL-mediated cytotoxicity are still obscure owing to the lack of a suitable experimental system. Recently, the presence of a disorder due to mutation of the Fas gene, the human counterpart of the lpr mouse, has been discovered.12-14 Since the function of Fas is completely abrogated in these patients, this disease is expected to provide useful materials for investigating the functions of Fas in humans. In the present study, we examined the cytotoxicity mechanisms of alloantigen-specific human CD4+ and CD8+ CTLs using cells from family members with the Fas gene mutation. The results showed that in contrast to murine CD4+ CTLs, the major pathway of alloantigen-specific human CD4+ CTLs appeared to be granule exocytosis, and not the Fas/Fas ligand system, the same as that of CD8+ CTLs.     Materials and methods Top Abstract Introduction Materials and methods Results Discussion References Fas-deficient family members Detailed information about the family members with the Fas gene mutation investigated in the present study has been reported previously.15 A homozygous point mutation was present in the splicing acceptor site of intron 3 of the Fas gene of this patient (Fas/). This mutation results in the skipping of exon 4 and complete loss of surface Fas expression. The patient's parents were both heterozygous for the same Fas gene mutation (Fas+/). The HLA types of each donor were as follows: Fas/patient, A24/24, B48/48, Cw8/-, DRB1*0401/*0401; Fas+/ mother, A24/2, B48/35, Cw3/-, DRB1*0401/*08032; Fas+/+ unrelated donor M.Y., A26/31, B61/62, Cw3/-, DRB1*0901/*1406; Fas+/+ unrelated donor H.O., A24/24, B52/54, Cw1/-, DRB1*04051/*1502. Generation of alloantigen-specific CD4+ and CD8+ CTL bulk lines and clones To generate alloantigen-specific CTL bulk lines and clones, peripheral blood mononuclear cells (PBMCs) from 2 unrelated individuals were cocultured with a mitomycin C (MMC)-treated Epstein-Barr virus-transformed B-lymphoblastoid cell line (B-LCL) established from the patient's PBMCs, or from the mother's PBMCs, in RPMI 1640 medium (Gibco, Grand Island, NY) supplemented with 10% heat-inactivated human AB-type serum, as described previously.16 CD4+ and CD8+ T lymphocytes were isolated from PBMCs that had been stimulated with an allogeneic LCL for 6 days by means of magnetizable polystyrene beads coated with anti-CD4 and anti-CD8 monoclonal antibody (mAb) (DYNAL, Oslo, Norway), respectively. Uncloned CD4+ and CD8+ T lymphocytes were further cultured in RPMI 1640 medium supplemented with 10% human serum and interleukin (IL)-2, stimulated with the allogeneic LCL weekly 3 times, and then used as CTL bulk lines. Alloantigen-specific CD4+ and CD8+ CTL clones were established from PBMCs that had been stimulated with an allogeneic LCL by limiting dilution and had been continuously cultured in RPMI 1640 medium supplemented with 10% human serum and IL-2 with repeated stimulation by the allogeneic LCL, as described previously.17 Cytotoxic assays Cytotoxicity was examined by standard 5-hour 51Cr release assays using B-LCLs, which are sensitive to Fas-mediated cytotoxicity,18,19 and freshly isolated sheep erythrocyte rosette-nonforming (E) cells, ie, B lymphocytes and monocytes, as target cells, as described previously.20 In order to examine the Ca2+-dependency of CTL-mediated cytotoxicity, ethylene glycol-bis(-aminoethyl ether)-N, N, N', N'-tetraacetic acid (EGTA) (Sigma, St Louis, MO) was added to the assay wells at 2 mmol/L with 2 mmol/L MgCl2. In some experiments, concanamycin A (CMA) (Wako, Osaka, Japan) was added to assay wells at 10 nmol/L to inhibit perforin-mediated cytotoxicity.21 Treatment of the cells with EGTA and CMA showed no toxic effect, as determined by the trypan blue exclusion test and 51Cr release assay. Detection of cytolytic mediator messenger RNA expression Expression of the main mediators of cytolysis, including perforin, granzyme B, and Fas ligand, by T lymphocytes was examined by reverse transcriptase polymerase chain reaction (RT-PCR), as described previously.22 Total RNA was extracted from CTLs that had been stimulated with allogeneic LCLs 5 days earlier, and complementary DNA (cDNA) was synthesized with Moloney murine leukemia virus reverse transcriptase. Amplification of the cDNAs by PCR was performed for 35 cycles with the use of the following primers: perforin, 5'-ACCAGCAATGTGCATGTGTCTGTG-3' and 5'-GAAGGAGGCCGTCATCTTGTGCTT-3'; granzyme B, 5'-TGCAGGAAGATCGAAAGTGCG-3' and 5'-GAGGCATGCCATTGTTTCGTC-3'; Fas ligand, 5'-ATAGGATCCATGTTTCTGCTCTTCCACCTACAGAAGGA-3' and 5'-ATAGAATTCTGACCAAGAGA- GAGCTCAGATACGTTGAC-3'. The expected lengths of the amplified cDNAs for the cytolytic mediators were 459 base pairs (bp), 180 bp, and 506 bp for perforin, granzyme B, and Fas ligand, respectively. Cytokine production For the assays of cytokine production, 1 × 106 clone cells and 3 × 105 MMC-treated allogeneic LCLs were suspended in 2 mL RPMI 1640 medium supplemented with 10% fetal calf serum and cultured in 16-mm wells. After 72 hours, the supernatants were collected from each well and were assayed for the production of various cytokines by enzyme-linked immunosorbent assay (ELISA) (Endogen, Woburn, MA).     Results Top Abstract Introduction Materials and methods Results Discussion References Cytotoxic activities of alloantigen-specific CD4+ and CD8+ CTL bulk lines and clones We established 3 CD4+ CTL bulk lines, 4 CD4+ CTL clones, 3 CD8+ CTL bulk lines, and 5 CD8+ CTL clones from PBMCs of an unrelated individual, M.Y., which had been stimulated with the Fas+/ LCL, and 3 CD4+ CTL bulk lines, 5 CD4+ CTL clones, 3 CD8+ CTL bulk lines, and 6 CD8+ CTL clones from M.Y.'s PBMCs, which had been stimulated with the Fas/ LCL. Similarly, 3 CD4+ CTL bulk lines, 5 CD4+ CTL clones, 3 CD8+ CTL bulk lines, and 4 CD8+ CTL clones were generated from PBMCs of an unrelated individual, H.O., which had been stimulated with the Fas+/ LCL, and 3 CD4+ CTL bulk lines, 5 CD4+ CTL clones, 3 CD8+ CTL bulk lines, and 4 CD8+ CTL clones were generated from H.O.'s PBMCs, which had been stimulated with the Fas/ LCL. We used B-LCLs and E cells (B lymphocytes and monocytes) as the target cells, since they express both HLA class I and HLA class II molecules, which are targets of alloantigen-specific CD8+ CTLs and CD4+ CTLs, respectively. The same cytotoxicity patterns were detected in all bulk lines and clones within each group, and representative data for CTL bulk lines and clones from each group are presented in Table 1. Both CD4+ and CD8+ CTLs showed cytotoxicity against allogeneic LCLs, which were used as stimulators, but not against autologous LCL. Since the cytotoxic activity of CD4+ CTL bulk lines and clones, and of CD8+ CTL bulk lines and clones, were inhibited by anti-HLA class II and anti-HLA class I framework mAb, respectively (data not shown), the cytotoxicity mediated by these CTLs seemed to be directed against allogeneic HLA antigens. The degrees of cytotoxicity mediated by CD4+ CTLs against Fas+/ and Fas/ target cells were almost the same. Similarly, CD8+ CTLs showed almost the same levels of cytotoxicity against Fas+/ and Fas/ target cells. These data strongly suggest that the cytotoxicity mediated by human CD4+ CTLs, as well as by CD8+ CTLs, is Fas-independent.                                View this table: [in this window] [in a new window]   Table 1. Cytotoxicity of alloantigen-specific CD4+ and CD8+ CTLs against allogeneic Fas+/ and Fas/ cells and autologous cells Expression of cytolytic mediators in alloantigen-specific CTL clones RT-PCR revealed that the main cytolytic mediators of CTLs, including perforin, granzyme B, and Fas ligand, were all expressed in all of the CD4+ and CD8+ CTL bulk lines and clones examined. Representative RT-PCR data are shown in Figure 1. Expression of both perforin and Fas ligand was confirmed by flow cytometry using anti-perforin and anti-Fas ligand mAbs (data not shown). View larger version (10K): [in this window] [in a new window]   Fig 1. Expression of cytolytic mediators in alloantigen-specific human CD4+ and CD8+ CTLs. Expression of messenger RNAs (mRNAs) for perforin, granzyme B, and Fas ligand was investigated by RT-PCR. The mRNAs were extracted from CD4+ clone #1-1 (lane 1), CD4+ clone #3-1 (lane 2), CD8+ clone #2-1 (lane 3), CD8+ clone #4-1 (lane 4), and a negative control B-cell line (lane 5). Lane M shows 100-bp ladder markers. Inhibition of cytotoxicity mediated by CD4+ and CD8+ alloantigen-specific CTL clones by EGTA and CMA It is well known that perforin-mediated cytotoxicity is Ca2+-dependent. As shown in Table 2, the cytotoxicity mediated by both CD4+ and CD8+ CTLs was inhibited completely by addition of the Ca2+-chelating agent EGTA, indicating that their cytotoxicity is Ca2+-dependent. In addition, the cytotoxicity mediated by both CD4+ and CD8+ CTLs appeared to be abrogated by the inhibitor of perforin-mediated cytotoxicity, CMA. These data show that the main pathways of cytotoxicity mediated by alloantigen-specific human CD4+ and CD8+ CTLs are both granule exocytosis.                                View this table: [in this window] [in a new window]   Table 2. Inhibition of cytotoxicity mediated by alloantigen-specific CD4+ and CD8+ CTLs by EGTA and CMA Cytokine production by alloantigen-specific CD4+ CTL clones Alloantigen-specific CD4+ CTL clones were cultured with or without Fas+/ and Fas/ LCL, and the supernatants were analyzed for the production of IL-4, IL-10, and interferon (IFN)-. As shown in Table 3, the majority of CD4+ CTL clones secreted all of these cytokines after stimulation with allogeneic LCL. Some of the CD4+ CTL clones secreted IL-10 and IFN-, but not IL-4. Therefore, the majority of alloantigen-specific human CD4+ CTLs generated in the present study can be classified as TH0 type CD4+ T-cell clones, with coexisting TH1 clones.                                View this table: [in this window] [in a new window]   Table 3. Cytokine production by alloantigen-specific CD4+ CTL clones     Discussion Top Abstract Introduction Materials and methods Results Discussion References In contrast to the detailed data available on the cytolytic mechanisms of murine CTLs obtained previously with the use of various kinds of mutant and knockout mice, the mechanisms of cytotoxicity mediated by human CTLs are still obscure. Using a novel experimental system with cells from family members with the Fas gene mutation, which is considered to be the human counterpart of the lpr mouse mutation, we have clearly demonstrated that granule exocytosis, and not the Fas/Fas ligand system, is the main pathway of cytotoxicity mediated by alloantigen-specific human CD4+ as well as CD8+ CTLs. Cytotoxicity mediated by alloantigen-specific human CD4+ as well as CD8+ CTLs are Ca2+-dependent, since addition of the Ca2+-chelating agent EGTA to the assay medium resulted in complete abrogation of cytotoxicity. Although Fas-dependent cytotoxicity has been reported to be Ca2+-independent,23 subsequent studies have revealed that even though the interaction between Fas ligand and Fas is Ca2+-independent, T-cell receptor-dependent up-regulation of Fas ligand on the cell surface requires extracellular Ca2+.24 Therefore, it could not be concluded that cytotoxicity mediated by human CD4+ CTLs is Fas-independent on the basis of the results obtained from the experiments using EGTA. However, we could conclude that cytotoxicity mediated by alloantigen-specific human CD4+ CTLs is Fas-independent, since they lysed allogeneic Fas/ and Fas+/ target cells, which shared an HLA haplotype, to the same degree. In addition, the cytotoxicity mediated by the CD4+ CTLs was almost completely inhibited by treatment with a potent inhibitor of the perforin-based cytotoxic pathway, CMA. These data strongly suggest that the main pathway of alloantigen-specific human CD4+ CTL-mediated cytotoxicity is granule exocytosis and that the cytolytic mechanism of human CD4+ CTLs generated in vitro is basically identical to that of CD8+ CTLs. The present data seem to be somewhat different from the recent findings obtained with murine systems indicating that granule exocytosis is the main pathway for CD8+ CTL- and natural killer cell-mediated cytotoxicity, whereas most CD4+ CTLs exert their cytotoxicity through the Fas/Fas ligand system.10,11 In murine models of acute GVHD and graft rejection using granzyme B-deficient mice, it has been reported that granzyme B plays an important role in cytotoxicity mediated by CD8+ CTLs, but not by CD4+ CTLs.25 The possibility that perforin-dependent cytotoxicity is restricted to some limited CD4+ populations is unlikely, since all alloantigen-specific CD4+ CTL bulk lines and clones examined showed Fas-independent cytotoxicity, and we have reported recently that herpes simplex virus-specific human CD4+ CTLs also exert antigen-specific and HLA class II-restricted cytotoxicity through Fas-independent mechanisms.16 In addition, we have recently found that cytotoxicity mediated by peptide-specific human CD4+ CTL clones is also Fas-independent (unpublished data). To clarify the subtype of CD4+ CTL clones generated in the present study, we examined their cytokine production profile. It appeared that the vast majority of CD4+ CTL clones generated were classified as TH0-type clones, and some CD4+ CTL clones secreted TH1-type cytokines. Although the relationship between the cytokine production profile and cytolytic pathway of CD4+ CTLs is unknown, the culture conditions of our experimental system might have favored the generation of TH0 CTLs, which predominantly follow the granule exocytosis pathway. Therefore, further study is necessary to clarify the cytolytic pathway of human CD4+ CTLs, which infiltrate various organs and exert cytotoxicity in vivo. Although the mechanisms of graft rejection and GVHD are complex, CTLs directed against alloantigens undoubtedly play crucial roles in these serious problems associated with organ transplantation. Recent studies have shown that in addition to CD8+ CTLs, CD4+ CTLs are also important for induction of graft rejection and GVHD.18,26,27 Thus, the present data indicate that we need to focus on the CTL granule exocytosis mechanism as well as the Fas/Fas ligand system when considering the development of novel methods for protection against alloreactivity.     Footnotes Submitted August 5, 1999; accepted December 8, 1999. Supported by grants from the Ministry of Education, Science, Sports and Culture of Japan; the Mochida Foundation for Medical and Pharmaceutical Research; the Inamori Foundation; the Suzuken Memorial Foundation; and the Naito Foundation. Reprints: Masaki Yasukawa, The First Department of Internal Medicine, Ehime University School of Medicine, Shigenobu, Ehime 791-0295, Japan; e-mail: yasukawa{at}m.ehime-u.ac.jp. The publication costs of this article were defrayed in part by page charge payment. Therefore, and solely to indicate this fact, this article is hereby marked "advertisement" in accordance with 18 U.S.C. section 1734.     References Top Abstract Introduction Materials and methods Results Discussion References 1. Henkart PA. Lymphocyte-mediated cytotoxicity: two pathways and multiple effector molecules. Immunity. 1994;1:343[Medline] [Order article via Infotrieve]. 2. Kägi D, Ledermann B, Bürki K, Zinkernagel RM, Hengartner H. Molecular mechanisms of lymphocyte-mediated cytotoxicity and their role in immunological protection and pathogenesis in vivo. Annu Rev Immunol. 1996;14:207[Medline] [Order article via Infotrieve]. 3. Watanabe-Fukunaga R, Brannan CI, Copeland NG, Jenkins NA, Nagata S. Lymphoproliferation disorder in mice explained by defects in Fas antigen that mediates apoptosis. Nature. 1992;356:314[Medline] [Order article via Infotrieve]. 4. Takahashi T, Tanaka M, Brannan CI, et al. Generalized lymphoproliferative disease in mice, caused by a point mutation in the Fas ligand. Cell. 1994;76:969[Medline] [Order article via Infotrieve]. 5. Kägi D, Vignaux F, Ledermann B, et al. Fas and perforin pathways as major mechanisms of T cell-mediated cytotoxicity. Science. 1994;265:528[Abstract/Free Full Text]. 6. Lowin B, Hahne M, Mattmann C, Tschopp J. Cytolytic T-cell cytotoxicity is mediated through perforin and Fas lytic pathways. Nature. 1994;370:650[Medline] [Order article via Infotrieve]. 7. Walsh CM, Matloubian M, Liu C-C, et al. Immune function in mice lacking the perforin gene. Proc Natl Acad Sci U S A. 1994;91:10,854[Abstract/Free Full Text]. 8. Kojima H, Shinohara N, Hanaoka S, et al. Two distinct pathways of specific killing revealed by perforin mutant cytotoxic T lymphocytes. Immunity. 1994;1:357[Medline] [Order article via Infotrieve]. 9. Simon MM, Hausmann M, Tran T, et al. In vitro- and ex vivo-derived cytolytic leukocytes from granzyme A × B double knockout mice are defective in granule-mediated apoptosis but not lysis of target cells. J Exp Med. 1997;186:1781[Abstract/Free Full Text]. 10. Kägi D, Ledermann B, Bürki K, et al. Cytotoxicity mediated by T cells and natural killer cells is greatly impaired in perforin-deficient mice. Nature. 1994;369:31[Medline] [Order article via Infotrieve]. 11. Stalder T, Hahn S, Erb P. Fas antigen is the major target molecule for CD4+ T cell-mediated cytotoxicity. J Immunol. 1994;152:1127[Abstract]. 12. Rieux-Laucat FR, Deist FL, Hivroz C, et al. Mutations in Fas associated with human lymphoproliferative syndrome and autoimmunity. Science. 1995;268:1347[Abstract/Free Full Text]. 13. Fisher GH, Rosenberg FJ, Straus SE, et al. Dominant interfering Fas gene mutations impair apoptosis in a human autoimmune lymphoproliferative syndrome. Cell. 1995;81:935[Medline] [Order article via Infotrieve]. 14. Nagata S. Human autoimmune lymphoproliferative syndrome, a defect in the apoptosis-inducing Fas receptor: a lesson from the mouse model. J Hum Genet. 1998;43:2[Medline] [Order article via Infotrieve]. 15. Kasahara Y, Wada T, Niida Y, et al. Novel Fas (CD95/APO-1) mutations in infants with a lymphoproliferative disorder. Int Immunol. 1998;10:195[Abstract/Free Full Text]. 16. Yasukawa M, Ohminami H, Yakushijin Y, et al. Fas-independent cytotoxicity mediated by human CD4+ CTL directed against herpes simplex virus-infected cells. J Immunol. 1999;162:6100[Abstract/Free Full Text]. 17. Yasukawa M, Inatsuki A, Kobayashi Y. Helper activity in antigen-specific antibody production mediated by CD4+ human cytotoxic T cell clones directed against herpes simplex virus. J Immunol. 1988;140:3419[Abstract]. 18. Nishimura M, Uchida S, Mitsunaga S, et al. Characterization of T-cell clones derived from peripheral blood lymphocytes of a patient with transfusion-associated graft-versus-host disease: Fas-mediated killing by CD4+ and CD8+ cytotoxic T-cell clones and tumor necrosis factor beta production by CD4+ T-cell clones. Blood. 1997;89:1440[Abstract/Free Full Text]. 19. Gagnon SJ, Ennis FA, Rothman AL. Bystander target cell lysis and cytokine production by dengue virus-specific human CD4+ cytotoxic T-lymphocyte clones. J Virol. 1999;73:3623[Abstract/Free Full Text]. 20. Yasukawa M, Inatsuki A, Horiuchi T, Kobayashi Y. Functional heterogeneity among herpes simplex virus-specific human CD4+ T cells. J Immunol. 1991;146:1341[Abstract]. 21. Kataoka T, Shinohara N, Takamiya H, et al. Concanamycin A, a powerful tool for characterization and estimation of contribution of perforin- and Fas-based lytic pathways in cell-mediated cytotoxicity. J Immunol. 1996;156:3678[Abstract]. 22. Yasukawa M, Ohminami H, Kaneko S, et al. CD4+ cytotoxic T-cell clones specific for bcr-abl b3a2 fusion peptide augment colony formation by chronic myelogenous leukemia cells in a b3a2-specific and HLA-DR-restricted manner. Blood. 1998;92:3355[Abstract/Free Full Text]. 23. Rouvier E, Luciani MF, Golstein P. Fas involvement in Ca2+-independent T cell-mediated cytotoxicity. J Exp Med. 1993;177:195[Abstract/Free Full Text]. 24. Lowin B, Mattman C, Hahne M, Tschopp J. Comparison of Fas (Apo-1/CD95)- and perforin-mediated cytotoxicity in primary T lymphocytes. Int Immunol. 1996;8:57[Abstract/Free Full Text]. 25. Graubert TA, Russell JH, Ley TJ. The role of granzyme B in murine models of acute graft-versus-host disease and graft rejection. Blood. 1996;87:1232[Abstract/Free Full Text]. 26. Friedman T, Shimizu A, Smith RN, et al. Human CD4+ T cells mediate rejection of porcine xenografts. J Immunol. 1999;162:5256[Abstract/Free Full Text]. 27. Faber LM, van Luxemburg-Heijis SAP, Veenhof WFJ, Willemze R, Falkenburg JHF. Generation of CD4+ cytotoxic T-lymphocyte clones from a patient with severe graft-versus-host disease after allogeneic bone marrow transplantation: implication for graft-versus-leukemia reaction. Blood. 1995;86:2821[Abstract/Free Full Text]. © 2000 by The American Society of Hematology.   CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this? This article has been cited by other articles: T. A. Haigh, X. Lin, H. Jia, E. P. Hui, A. T. C. Chan, A. B. Rickinson, and G. S. Taylor EBV Latent Membrane Proteins (LMPs) 1 and 2 as Immunotherapeutic Targets: LMP-Specific CD4+ Cytotoxic T Cell Recognition of EBV-Transformed B Cell Lines J. Immunol., February 1, 2008; 180(3): 1643 - 1654. [Abstract] [Full Text] [PDF] A. Hombach, H. Kohler, G. Rappl, and H. Abken Human CD4+ T Cells Lyse Target Cells via Granzyme/Perforin upon Circumvention of MHC Class II Restriction by an Antibody-Like Immunoreceptor J. Immunol., October 15, 2006; 177(8): 5668 - 5675. 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