OS06.4A Identification of T cell receptors targeting ZFTA-RELA fusion-positive ependymoma

2021 ◽  
Vol 23 (Supplement_2) ◽  
pp. ii9-ii9
Author(s):  
N Kehl ◽  
M Friedrich ◽  
M Kilian ◽  
T Zheng ◽  
K Pajtler ◽  
...  

Abstract BACKGROUND The oncogenic gene fusion between ZFTA (formerly C11orf95) and RELA has in recent years been highlighted as oncogenic driver event ultimately leading to malignant transformation and progression of ependymoma. Representing a genetic hallmark in 17.6% of ependymomas, ZFTA-RELA fusion-positive tumors qualified as separate diagnostic entity in the 2016 revision of the WHO classification of CNS tumors. This tumor entity mainly occurs in pediatric patients and is characterized by poor prognosis and the lack of biology-driven therapy. RESULTS De novo prediction of putative gene fusion-derived neoepitopes in malignant CNS diseases yielded several potential candidates suitable for screening. Of these, vaccination of A2.DR1-transgenic major histocompatibility complex (MHC)-humanized mice with in silico compiled peptide vaccines encompassing the ZFTA-RELA fusion sequence elicited robust antigen-specific CD4+-restricted immune responses. We identified ZFTA-RELA-reactive T cell clones by multiplexed Interferon-γ / Interleukin-2 recall response. Single-cell VDJ-sequencing of reactive T cells demonstrated a highly clonal T cell receptor (TCR) repertoire and shared clonotypes among all vaccinated animals. Matching TCRα/β chains have been assembled from single-cell sequencing data and cloned for functional testing of neoepitope-reactive TCR-transgenic T cells in vitro as well as in vivo using a transposon system-based immunocompetent, MHC-humanized ZFTA-RELA fusion-positive ependymoma model. CONCLUSION Here we identify the oncogenic ZFTA-RELA gene fusion product as a novel tumor-specific neoepitope that is recognized by MHC class II-restricted TCRs. Therapeutic efficacy of TCR-transgenic cell therapy can be further investigated using an immunocompetent MHC-humanized mouse model of ZFTA-RELA fusion-positive ependymoma. Our findings provide initial evidence for neoepitope-specific immunotherapy in pediatric CNS tumors.

Blood ◽  
2006 ◽  
Vol 109 (8) ◽  
pp. 3325-3332 ◽  
Author(s):  
Anders Woetmann ◽  
Paola Lovato ◽  
Karsten W. Eriksen ◽  
Thorbjørn Krejsgaard ◽  
Tord Labuda ◽  
...  

AbstractBacterial toxins including staphylococcal enterotoxins (SEs) have been implicated in the pathogenesis of cutaneous T-cell lymphomas (CTCLs). Here, we investigate SE-mediated interactions between nonmalignant T cells and malignant T-cell lines established from skin and blood of CTCL patients. The malignant CTCL cells express MHC class II molecules that are high-affinity receptors for SE. Although treatment with SE has no direct effect on the growth of the malignant CTCL cells, the SE-treated CTCL cells induce vigorous proliferation of the SE-responsive nonmalignant T cells. In turn, the nonmalignant T cells enhance proliferation of the malignant cells in an SE- and MHC class II–dependent manner. Furthermore, SE and, in addition, alloantigen presentation by malignant CTCL cells to irradiated nonmalignant CD4+ T-cell lines also enhance proliferation of the malignant cells. The growth-promoting effect depends on direct cell-cell contact and soluble factors such as interleukin-2. In conclusion, we demonstrate that SE triggers a bidirectional cross talk between nonmalignant T cells and malignant CTCL cells that promotes growth of the malignant cells. This represents a novel mechanism by which infections with SE-producing bacteria may contribute to pathogenesis of CTCL.


1997 ◽  
Vol 185 (2) ◽  
pp. 219-230 ◽  
Author(s):  
Joaquín Madrenas ◽  
Luan A. Chau ◽  
Judy Smith ◽  
Jeffrey A. Bluestone ◽  
Ronald N. Germain

One hypothesis seeking to explain the signaling and biological properties of T cell receptor for antigen (TCR) partial agonists and antagonists is the coreceptor density/kinetic model, which proposes that the pharmacologic behavior of a TCR ligand is largely determined by the relative rates of (a) dissociation of ligand from an engaged TCR and (b) recruitment of lck-linked coreceptors to this ligand-engaged receptor. Using several approaches to prevent or reduce the association of CD4 with occupied TCR, we demonstrate that consistent with this hypothesis, the biological and biochemical consequence of limiting this interaction is to convert typical agonists into partial agonist stimuli. Thus, adding anti-CD4 antibody to T cells recognizing a wild-type peptide–MHC class II ligand leads to disproportionate inhibition of interleukin-2 (IL-2) relative to IL-3 production, the same pattern seen using a TCR partial agonist/antagonist. In addition, T cells exposed to wild-type ligand in the presence of anti-CD4 antibodies show a pattern of TCR signaling resembling that seen using partial agonists, with predominant accumulation of the p21 tyrosine-phosphorylated form of TCR-ζ, reduced tyrosine phosphorylation of CD3ε, and no detectable phosphorylation of ZAP-70. Similar results are obtained when the wild-type ligand is presented by mutant class II MHC molecules unable to bind CD4. Likewise, antibody coligation of CD3 and CD4 results in an agonist-like phosphorylation pattern, whereas bivalent engagement of CD3 alone gives a partial agonist-like pattern. Finally, in accord with data showing that partial agonists often induce T cell anergy, CD4 blockade during antigen exposure renders cloned T cells unable to produce IL-2 upon restimulation. These results demonstrate that the biochemical and functional responses to variant TCR ligands with partial agonist properties can be largely reproduced by inhibiting recruitment of CD4 to a TCR binding a wild-type ligand, consistent with the idea that the relative rates of TCR–ligand disengagement and of association of engaged TCR with CD4 may play a key role in determining the pharmacologic properties of peptide–MHC molecule ligands. Beyond this insight into signaling through the TCR, these results have implications for models of thymocyte selection and the use of anti-coreceptor antibodies in vivo for the establishment of immunological tolerance.


1990 ◽  
Vol 171 (5) ◽  
pp. 1453-1467 ◽  
Author(s):  
C C Hughes ◽  
C O Savage ◽  
J S Pober

We have demonstrated that endothelial cells (EC) augment IL-2 production by PHA-stimulated PBMC or purified CD4+ T cells and that the increase is apparent both in the amount of soluble IL-2 secreted and in the level of specific mRNA detectable by Northern blot hybridization. The ability of EC to affect levels of IL-2 cannot be reproduced by soluble factors, including the cytokines IL-1, IL-6, IFN-gamma, or TNF, conditioned medium from resting EC or IL-1, IFN-gamma- or TNF-treated EC, or from resting PBMC + EC cultures. Separation of the EC and PBMC by a Transwell membrane demonstrated that cell contact was required for augmentation of IL-2 synthesis and that this effect was unlikely to be mediated by a short-lived soluble signal. The cell-cell interaction required the ligand pair CD2/LFA-3, since augmentation could be inhibited by antibodies to these structures. Antibodies to ICAM-1, LFA-1, CD4, and MHC class II were without effect. A contact-dependent pathway involving CD2/LFA-3 interactions also may be used by EC to augment IL-2 production from T cells stimulated more specifically through the TCR/CD3 complex with antibody OKT3. This pathway provides a proliferative advantage to T cells stimulated with OKT3 in the presence of EC and may also be involved in the proliferative response of resting T cells to allogeneic class II MHC-expressing EC. We propose that EC augmentation of T cell IL-2 synthesis may be critical in the ability of EC to elicit primary T cell antigen responses and may have consequences for the development of localized cell-mediated immune reactions.


Blood ◽  
2006 ◽  
Vol 108 (2) ◽  
pp. 600-608 ◽  
Author(s):  
Georgina H. Cornish ◽  
Linda V. Sinclair ◽  
Doreen A. Cantrell

Although interleukin 2 (IL-2) and IL-15 signal through the common gamma chain (γc) and through IL-2 receptor β–chain (CD122) subunits, they direct distinct physiologic and immunotherapeutic responses in T cells. The present study provides some insight into why IL-2 and IL-15 differentially regulate T-cell function by revealing that these cytokines are strikingly distinct in their ability to control protein synthesis and T-cell mass. IL-2 and IL-15 are shown to be equivalent mitogens for antigen-stimulated CD8+ T cells but not for equivalent growth factors. Antigen-primed T cells cannot autonomously maintain amino acid incorporation or de novo protein synthesis without exogenous cytokine stimulation. Both IL-2 and IL-15 induce amino acid uptake and protein synthesis in antigen-activated T cells; however, the IL-2 response is strikingly more potent than the IL-15 response. The differential action of IL-2 and IL-15 on amino acid uptake and protein synthesis is explained by temporal differences in signaling induced by these 2 cytokines. Hence, the present results show that cytokines that are equivalent mitogens can have different potency in terms of regulating protein synthesis and cell growth.


Blood ◽  
2003 ◽  
Vol 101 (7) ◽  
pp. 2704-2710 ◽  
Author(s):  
Julia Y. S. Tsang ◽  
Jian Guo Chai ◽  
Robert Lechler

Antigen presentation by activated human and rat CD4+ T cells has long been known to induce hyporesponsiveness due to a combination of anergy and apoptosis. It has been assumed that no such phenomenon occurs in mice due to the inability of mouse T cells to synthesize major histocompatibility complex (MHC) class II molecules. There have been several recent descriptions of the transfer of molecules, including MHC molecules, from antigen-presenting cells (APCs) to T cells. Here, we describe the acquisition of MHC class II molecules by T-cell receptor (TCR)–transgenic T cells and T-hybridoma cells following culture with APCs. Acquisition was markedly enhanced by T-cell activation either due to cognate recognition of antigen or anti-CD3 activation. When activation was induced by antigen recognition, preferential acquisition of complexes of class II molecules displaying cognate peptide was observed; in contrast, following activation by anti-CD3 the acquisition of class II molecules was MHC unrestricted. T cells that had acquired MHC class II:peptide complexes were able to act as APCs and induced proliferation and interleukin-2 secretion by resting T cells. However, when activated T cells that had acquired MHC class II:peptide complexes engaged in T:T interactions, this led to an increase in apoptosis and the induction of hyporesponsiveness. These results raise the possibility that the acquisition of MHC class II:peptide complexes by T cells during an immune response may serve to limit clonal expansion, including that induced by alloantigen following tissue or stem cell transplantation.


1994 ◽  
Vol 179 (6) ◽  
pp. 1945-1956 ◽  
Author(s):  
D A Vignali ◽  
J L Strominger

Hen egg lysozyme 52-61-specific CD4+ T cells responded by interleukin 2 (IL-2) secretion to any peptide containing this epitope regardless of length of NH2- and COOH-terminal composition. However, CD4- variants could only respond to peptides containing the two COOH-terminal tryptophans at positions 62 and 63. Substitutions at these positions defined patterns of reactivity that were specific for individual T cells inferring a T cell receptor (TCR)-based phenomenon. Thus, the fine specificity of major histocompatibility complex (MHC)-peptide recognition by the TCR was dramatically affected by CD4 and the COOH-terminal peptide composition. Peptides that failed to induce IL-2 secretion in the CD4- variants nevertheless induced strong tyrosine phosphorylation of CD3 zeta. Thus, whereas the TCR still recognized and bound to the MHC class II-peptide complex resulting in protein phosphorylation, this interaction failed to induce effective signal transduction manifested by IL-2 secretion. This provides a clear example of differential signaling mediated by peptides known to be naturally processed. In addition, the external domains of CD4, rather than its cytoplasmic tail, were critical in aiding TCR recognition of all peptides derived from a single epitope. These data suggest that the nested flanking residues, which are present on MHC class II but not class I bound peptides, are functionally relevant.


2019 ◽  
Vol 39 (16) ◽  
Author(s):  
Debojit Bose ◽  
Alexander Neumann ◽  
Bernd Timmermann ◽  
Stefan Meinke ◽  
Florian Heyd

ABSTRACTT cells are nodal players in the adaptive immune response against pathogens and malignant cells. Alternative splicing plays a crucial role in T cell activation, which is analyzed mainly at later time points upon stimulation. Here we have discovered a 2-h time window early after stimulation where optimal splicing efficiency or, more generally, gene expression efficiency is crucial for successful T cell activation. Reducing the splicing efficiency at 4 to 6 h poststimulation significantly impaired murine T cell activation, which was dependent on the expression dynamics of the Egr1–Nab2–interleukin-2 (IL-2) pathway. This time window overlaps the time of peak IL-2de novotranscription, which, we suggest, represents a permissive time window in which decreased splicing (or transcription) efficiency reduces mature IL-2 production, thereby hampering murine T cell activation. Notably, the distinct expression kinetics of the Egr1–Nab2–IL-2 pathway between mouse and human render human T cells refractory to this vulnerability. We propose that the rational temporal modulation of splicing or transcription during peakde novoexpression of key effectors can be used to fine-tune stimulation-dependent biological outcomes. Our data also show that critical consideration is required when extrapolating mouse data to the human system in basic and translational research.


1989 ◽  
Vol 169 (3) ◽  
pp. 921-931 ◽  
Author(s):  
L C Eisenlohr ◽  
C J Hackett

The contribution of viral infectivity to the expression of MHC class II-restricted T cell determinants was studied. A murine I-Ed-restricted T cell hybridoma recognizing the neuraminidase (NA) glycoprotein of influenza PR8 virus was stimulated strongly by infectious virus but failed to recognize antigen introduced on noninfectious virions. Recognition correlated with the de novo synthesis of viral NA within infected APC. The effectiveness of infectious virus did not depend strictly upon the amount of NA present in cultures, since high NA concentrations could be achieved by addition of nonreplicative virus without being stimulatory for NA-specific T cells. Recognition of a determinant generated only when synthesized in murine host cells was ruled out, since, in high concentration, NA isolated from purified egg-grown virions, even if reduced and alkylated, was recognized by the T hybridoma clone. Isolated NA was recognized when added to pre-fixed APC, suggesting that this form of antigen was able to bypass the usual processing pathway of exogenous proteins. Data suggest that endogenously synthesized antigen may contribute most significantly to presentation of labile T cell determinants. In addition to NA, recognition of an I-Ed-restricted determinant of the influenza hemagglutinin (HA) molecule, shown previously to have a relatively short half-life on APC surfaces, was enhanced greatly by infectious virus. In contrast, T cell recognition of a more stably expressed I-Ed-restricted site of the same HA polypeptide was only marginally improved on infected APC.


Blood ◽  
2006 ◽  
Vol 109 (1) ◽  
pp. 244-252 ◽  
Author(s):  
Ellen Kreijveld ◽  
Hans J. P. M. Koenen ◽  
Luuk B. Hilbrands ◽  
Hans J. P. van Hooff ◽  
Irma Joosten

Abstract The induction of transplantation tolerance involves a T-cell–mediated process of immune regulation. In clinical transplantation, the use of immunosuppressive drugs that promote or facilitate this process would be highly desirable. Here, we investigated the tolerance-promoting potential of the immunosuppressive drug FK778, currently under development for clinical therapy. Using a human allogeneic in vitro model we showed that, upon T-cell receptor (TCR) triggering, FK778 induced a regulatory phenotype in CD4+CD25− T cells. Purified CD4+CD25− T cells primed in the presence of FK778 showed hyporesponsiveness upon restimulation with alloantigen in the absence of the drug. This anergic state was reversible by exogenous interleukin-2 (IL-2) and was induced independent of naturally occurring CD4+CD25+ regulatory T cells. Pyrimidine restriction was a crucial requirement for the de novo induction of regulatory activity by FK778. The FK778-induced anergic cells showed suppressor activity in a cell-cell contact–dependent manner; were CD25high, CD45RO+, CD27−, and CD62L−; and expressed cytotoxic T-lymphocyte–associated antigen-4 (CTLA-4), glucocorticoid-induced tumor necrosis factor receptor (GITR), and FoxP3. The cells revealed delayed p27kip1 degradation and enhanced phosphorylation of STAT3. In conclusion, the new drug FK778 shows tolerizing potential through the induction of a regulatory T-cell subset in CD4+CD25− T cells.


2020 ◽  
Author(s):  
Haitao Luo ◽  
Dechao Bu ◽  
Lijuan Shao ◽  
Yang Li ◽  
Liang Sun ◽  
...  

AbstractThe development of new therapeutic targets for cancer immunotherapies and the development of new biomarkers require deep understanding of T cells. To date, the complete landscape and systematic characterization of long noncoding RNAs (lncRNAs) in T cells in cancer immunity are lacking. Here, by systematically analyzing full-length single-cell RNA sequencing (scRNA-seq) data of more than 20,000 T cell libraries across three cancer types, we provide the first comprehensive catalog and the functional repertoires of lncRNAs in human T cells. Specifically, we developed a custom pipeline for de novo transcriptome assembly obtaining 9,433 novel lncRNA genes that increased the number of current human lncRNA catalog by 16% and nearly doubled the number of lncRNAs expressed in T cells. We found that a portion of expressed genes in single T cells were lncRNAs which have been overlooked by the majority of previous studies. Based on metacell maps constructed by MetaCell algorithm that partition scRNA-seq datasets into disjointed and homogenous groups of cells (metacells), 154 signature lncRNAs associated with effector, exhausted, and regulatory T cell states are identified, 84 of which are functionally annotated based on co-expression network, indicating that lncRNAs might broadly participate in regulation of T cell functions. Our findings provide a new point of view and resource for investigating the mechanisms of T cell regulation in cancer immunity as well as for novel cancer-immune biomarker development and cancer immunotherapies.


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