Pathogenesis of an Infectious Mononucleosis-like Disease Induced by a Murine γ-Herpesvirus: Role for a Viral Superantigen?

The murine γ-herpesvirus 68 has many similarities to EBV, and induces a syndrome comparable to infectious mononucleosis (IM). The frequency of activated CD8+ T cells (CD62Llo) in the peripheral blood increased greater than fourfold by 21 d after infection of C57BL/6J (H-2b) mice, and remained high for at least a further month. The spectrum of T cell receptor usage was greatly skewed, with as many as 75% of the CD8+ T cells in the blood expressing a Vβ4+ phenotype. Interestingly, the Vβ4 dominance was also seen, to varying extents, in H-2k, H-2d, H-2u, and H-2q strains of mice. In addition, although CD4 depletion from day 11 had no effect on the Vβ4 bias of the T cells, the Vβ4+CD8+ expansion was absent in H-2IAb–deficient congenic mice. However, the numbers of cycling cells in the CD4 antibody–depleted mice and mice that are CD4 deficient as a consequence of the deletion of MHC class II, were generally lower. The findings suggest that the IM-like disease is driven both by cytokines provided by CD4+ T cells and by a viral superantigen presented by MHC class II glycoproteins to Vβ4+CD8+ T cells.

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Increased frequency of T cell receptor V alpha 12.1 expression on CD8+ T cells: evidence that V alpha participates in shaping the peripheral T cell repertoire.

Journal of Experimental Medicine ◽

10.1084/jem.174.3.639 ◽

1991 ◽

Vol 174 (3) ◽

pp. 639-648 ◽

Cited By ~ 52

Author(s):

H DerSimonian ◽

H Band ◽

M B Brenner

Keyword(s):

T Cells ◽

T Cell ◽

Gene Product ◽

T Cell Receptor ◽

Cd8 T Cells ◽

Peripheral Blood ◽

Cell Receptor ◽

Class I ◽

Class I Mhc ◽

Alpha Gene

The T cell receptor repertoire has a potential for vast diversity. However, this diversity is limited by the fact that the majority of thymocytes die as the repertoire is shaped by positive and negative selection events during development. Such thymic selection affecting TCR V beta gene segment usage has been demonstrated in the mouse. However, similar data has not been forthcoming in man, and little is known about the role of the TCR alpha chain in antigen/major histocompatibility complex (MHC) recognition in any species. Here, we used a monoclonal antibody recognizing the TCR V alpha 12.1 gene product to assess the expression of this gene in the peripheral blood of man. In most individuals tested, the percentage of cells expressing V alpha 12.1 was significantly higher in CD8+ T cells than in CD4+ T cells. That the V alpha gene product itself was responsible for this increased expression in CD8+ T cells was underscored by the lack of substantial skewing of V beta usage in the V alpha 12.1-bearing T cells. Moreover, the skewed expression of V alpha 12.1 was already present at birth, indicating that it was likely to be due to a developmental process rather than the result of exposure to environmental antigens. Based on the established role for CD8 in binding to class I MHC molecules, we suggest that increased expression of V alpha 12.1 on CD8+ T cells points to a role for TCR's using V alpha 12.1 in class I MHC/Ag recognition. These results indicate that V alpha gene usage in the peripheral blood of man is not random, and they support a role for V alpha as a participant in the self-MHC recognition process that shapes the TCR repertoire.

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OS12.4.A MHC class II-restricted transgenic T cell receptor therapy targeting mutant capicua transcriptional repressor in experimental gliomas

Neuro-Oncology ◽

10.1093/neuonc/noab180.048 ◽

2021 ◽

Vol 23 (Supplement_2) ◽

pp. ii15-ii15

Author(s):

M Kilian ◽

M Friedrich ◽

K Sanghvi ◽

E Green ◽

S Pusch ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Receptor ◽

Mhc Class Ii ◽

Transcriptional Repressor ◽

Cell Receptor ◽

Class Ii ◽

Therapeutic Interventions ◽

Humanized Mice ◽

Adoptive Therapy

Abstract BACKGROUND Glioma subtypes are classified according to their characteristic mutations and show a high degree of resistance to standard therapeutic interventions such as radiotherapy and alkylating chemotherapy. Some of these characteristic mutations have shown to generate immunogenic neoepitopes that can be targeted with immunotherapy. 70% of oligodendrogliomas carry capicua transcriptional repressor (CIC) inactivating mutations. RESULTS In a screen for potential immunogenic glioma neoepitopes we identified recurrent CIC hotspot mutations at position 215 (CICR215W/Q) expressed in a subset of oligodendrogliomas as an immunogenic major histocompatibility complex (MHC) class II-restricted neoepitopes. Peptide-based vaccination of MHC-humanized mice resulted in the generation of robust mutation-specific T cell responses against CICR215W/Q, restricted to MHC class II. Droplet-based single cell T cell receptor (TCR) sequencing from CICR215W-specific T cell lines enabled retrieval of MHC class II-restricted CICR215W-reactive TCRs. By retroviral transduction of T cells, we established a flow cytometry-based testing platform of retrieved TCRs and were able to show the top reactive TCR against CICR215W to be shared between individual mice. Using a newly developed glioma model in MHC-humanized mice induced by CRISPR-based delivery of tumor suppressor targeting guide RNAs, we show that adoptive intraventricular transfer of CICR215W-specific TCR-transgenic T cells exert anti-tumor responses against CICR215W-expressing syngeneic gliomas. CONCLUSION The integration of immunocompetent MHC-humanized orthotopic glioma models in the discovery of shared immunogenic glioma neoepitopes facilitates the identification and preclinical testing of HLA-restricted neoepitope-specific TCRs for locoregional TCR-transgenic T cell adoptive therapy.

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A T Cell Receptor Signaling Mutant Reveals Two Distinct Populations of IL-17 Producing CD4+ T Cells

Blood ◽

10.1182/blood.v118.21.186.186 ◽

2011 ◽

Vol 118 (21) ◽

pp. 186-186

Author(s):

Jiyeon S Kim ◽

Jennifer E Smith-Garvin ◽

Martha S Jordan ◽

Gary A Koretzky

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Receptor ◽

Mhc Class Ii ◽

Cd4 T Cells ◽

Th17 Cells ◽

Critical Role ◽

Cell Receptor ◽

Class Ii ◽

Interleukin 17

Abstract Abstract 186 Interleukin-17 (IL-17) producing CD4+ T cells (Th17 cells) are essential for immune responses in mucosal and epithelial sites which are the first line of host defense. Th17 cells play a critical role in the pathogenesis of many inflammatory and autoimmune diseases, and the role of IL-17 and Th17 cells in cancer has recently become the focus of extensive investigation. Most studies to date have focused on elucidating the cell extrinsic requirements for differentiation of Th17 cells from naïve CD4+ T cells in peripheral effector sites. Here we report an unconventional population of Th17 cells, “natural Th17 cells” (nTh17), that acquire effector function during development in the thymus, thereby distinguishing them from conventional Th17 cells which require antigen encounter and differentiation in the periphery. We show that these nTh17 cells are present and indeed develop in the thymus using fetal thymic organ culture. nTh17 cells express surface markers consistent with an innate and/or activated phenotype and their development is dependent on selection by MHC class II in the thymus. Yet unlike conventional CD4+ T cells, MHC class II expression on thymic cortical epithelium is not sufficient for their development, rather expression on medullary epithelium is necessary. In addition, T cell receptor (TCR) repertoire analysis of nTh17 cells revealed unique characteristics in TCR gene usage compared to conventional Th17 cells. A mouse model with a mutation in the TCR signaling protein SLP76 (SLP76 Y145F mice) further highlights the difference between the two distinct Th17 populations. SLP76 Y145F mice have increased numbers of nTh17 cells in the thymus compared to wild-type mice. However, peripheral naïve CD4+ T cells from these mice showed severely defective IL-17 production when cultured in vitro under conditions promoting Th17 cell differentiation. This defect was reflected in vivo as CD4+ T cells in the small intestinal lamina propria of SLP76 Y145F mice fail to produce IL-17. Using mixed radiation bone marrow chimeras, we found that the aberrant Th17 phenotype in the thymus and periphery of SLP76 Y145F mice is cell-intrinsic. Finally, adoptive transfer of purified nTh17 cells into RAG-deficient host mice revealed preferential homing of nTh17 cells to thymus and lung compared to other comparison/competitive populations that were co-transferred. Taken together, our data suggest a distinct population of Th17 cells that have characteristics of innate lymphocytes that function at the interface between innate and adaptive immunity. Understanding the biology of nTh17 cells will provide insight into the recently identified Th17 cells in human thymi and umbilical cord blood. Disclosures: No relevant conflicts of interest to declare.

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Amino acid residues that flank core peptide epitopes and the extracellular domains of CD4 modulate differential signaling through the T cell receptor.

Journal of Experimental Medicine ◽

10.1084/jem.179.6.1945 ◽

1994 ◽

Vol 179 (6) ◽

pp. 1945-1956 ◽

Cited By ~ 68

Author(s):

D A Vignali ◽

J L Strominger

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Receptor ◽

Mhc Class Ii ◽

Interleukin 2 ◽

Cell Receptor ◽

Class Ii ◽

Peptide Epitopes ◽

Differential Signaling ◽

Effective Signal

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.

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T cell receptor-major histocompatibility complex class II interaction is required for the T cell response to bacterial superantigens.

Journal of Experimental Medicine ◽

10.1084/jem.180.5.1921 ◽

1994 ◽

Vol 180 (5) ◽

pp. 1921-1929 ◽

Cited By ~ 28

Author(s):

N Labrecque ◽

J Thibodeau ◽

W Mourad ◽

R P Sékaly

Keyword(s):

T Cells ◽

Major Histocompatibility Complex ◽

T Cell ◽

T Cell Receptor ◽

Mhc Class Ii ◽

Cell Receptor ◽

Class Ii ◽

Beta Chain ◽

Major Histocompatibility ◽

Histocompatibility Complex

Bacterial and retroviral superantigens (SAGs) stimulate a high proportion of T cells expressing specific variable regions of the T cell receptor (TCR) beta chain. Although most alleles and isotypes bind SAGs, polymorphisms of major histocompatibility complex (MHC) class II molecules affect their presentation to T cells. This observation has raised the possibility that a TCR-MHC class II interaction can occur during this recognition process. To address the importance of such interactions during SAG presentation, we have used a panel of murine T cell hybridomas that respond to the bacterial SAG Staphylococcal enterotoxin B (SEB) and to the retroviral SAG Mtv-7 when presented by antigen-presenting cells (APCs) expressing HLA-DR1. Amino acid substitutions of the putative TCR contact residues 59, 64, 66, 77, and 81 on the DR1 beta chain showed that these amino acids are critical for recognition of the SAG SEB by T cells. TCR-MHC class II interactions are thus required for T cell recognition of SAG. Moreover, Mtv-7 SAG recognition by the same T cell hybridomas was not affected by these mutations, suggesting that the topology of the TCR-MHC class II-SAG trimolecular complex could be different from one TCR to another and from one SAG to another.

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Antagonist Peptide Selects Thymocytes Expressing a Class II Major Histocompatibility Complex–restricted T Cell Receptor into the CD8 Lineage

Journal of Experimental Medicine ◽

10.1084/jem.188.6.1083 ◽

1998 ◽

Vol 188 (6) ◽

pp. 1083-1089 ◽

Cited By ~ 16

Author(s):

Ariane Volkmann ◽

Thomas Barthlott ◽

Siegfried Weiss ◽

Ronald Frank ◽

Brigitta Stockinger

Keyword(s):

T Cells ◽

Major Histocompatibility Complex ◽

Cell Differentiation ◽

T Cell ◽

T Cell Receptor ◽

Mhc Class Ii ◽

Cell Receptor ◽

Class Ii ◽

T Cell Differentiation ◽

Histocompatibility Complex

CD4/CD8 lineage decision is an important event during T cell maturation in the thymus. CD8 T cell differentiation usually requires corecognition of major histocompatibility complex (MHC) class I by the T cell receptor (TCR) and CD8, whereas CD4 T cells differentiate as a consequence of MHC class II recognition by the TCR and CD4. The involvement of specific peptides in the selection of T cells expressing a particular TCR could be demonstrated so far for the CD8 lineage only. We used mice transgenic for an MHC class II-restricted TCR to investigate the role of antagonistic peptides in CD4 T cell differentiation. Interestingly, antagonists blocked the development of CD4+ cells that normally differentiate in thymus organ culture from those mice, and they induced the generation of CD8+ cells in thymus organ culture from mice impaired in CD4+ cell development (invariant chain–deficient mice). These results are in line with recent observations that antagonistic signals direct differentiation into the CD8 lineage, regardless of MHC specificity.

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