Domains of the TCR beta-chain required for early thymocyte development.

The T cell receptor beta (TCR beta) chain controls the developmental transition from CD4-CD8- to CD4+8+thymocytes. We show that the extracellular constant region and the transmembrane region, but not the variable domain or cytoplasmic tail of the TCR beta chain are required for this differentiation step. TCR beta mutant chains lacking the cytoplasmic tail can be found at the cell surface both in functional TCR/CD3 complexes and in a GPI-anchored monomeric form indicating that the cytoplasmic tail of the TCR beta chain functions as an ER retention signal. The concordance between cell surface expression of the mutant chains as TCR/CD3 complexes and their capacity to mediate thymocyte differentiation supports the CD3 mediated feedback model in which preTCR/CD3 complexes control the developmental transition from CD4-CD8- to CD4+CD8+thymocytes.

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A lysosomal targeting signal in the cytoplasmic tail of the beta chain directs HLA-DM to MHC class II compartments.

The Journal of Cell Biology ◽

10.1083/jcb.131.2.351 ◽

1995 ◽

Vol 131 (2) ◽

pp. 351-369 ◽

Cited By ~ 137

Author(s):

M S Marks ◽

P A Roche ◽

E van Donselaar ◽

L Woodruff ◽

P J Peters ◽

...

Keyword(s):

Cell Surface ◽

Immunoelectron Microscopy ◽

Cytoplasmic Tail ◽

Surface Expression ◽

Class Ii ◽

Cell Surface Expression ◽

Beta Chain ◽

Lysosomal Compartment ◽

Mhc Ii ◽

Alpha Beta

In human B cells, class II molecules of the major histocompatibility complex (MHC-II) accumulate in an endosomal/lysosomal compartment, the MIIC, in which they may encounter and bind peptides. An additional molecule required for MHC-II peptide binding, HLA-DM (DM), has also been localized to the MIIC. Neither the relationship of the MIIC to the endosomal system nor the mechanisms by which DM localizes to the MIIC are understood. To address these issues, DM localization was analyzed in cells that do or do not express MHC-II. DM alpha beta heterodimers were localized in transfected MHC-II-negative HeLa and NRK cells, in the absence of the MHC-II-associated invariant chain, to a prelysosomal/lysosomal compartment by immunofluorescence microscopy. To identify a potential targeting determinant, we analyzed the localization of a chimeric protein, T-T-Mb, in which the cytoplasmic tail of murine DM beta (Mb) was appended to the lumenal and transmembrane domains of a cell surface protein, Tac. Like intact DM, T-T-Mb was localized to a lysosomal compartment in HeLa and NRK cells, as judged by immunofluorescence and immunoelectron microscopy. T-T-Mb was rapidly degraded in this compartment by a process that was blocked by inhibitors of lysosomal proteolysis. The DM beta cytoplasmic tail also mediated internalization of anti-Tac antibody from the cell surface and delivery to lysosomes. Deletion from the DM beta cytoplasmic tail of the tyrosine-based motif, YTPL, resulted in cell surface expression of T-T-Mb and a loss of both degradation and internalization; alanine scanning mutagenesis showed that the Y and L residues were critical for these functions. Similarly, mutation of the same Y residue within full-length DM beta resulted in cell surface expression of DM alpha beta heterodimers. Lastly, T-T-Mb was localized by immunoelectron microscopy to the MIIC in a human B lymphoblastoid cell line. Our results suggest that a motif, YTPL, in the cytoplasmic tail of the beta chain of DM is sufficient for targeting either to lysosomes or to the MIIC.

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Allelic Exclusion in pTα-deficient Mice: No Evidence for Cell Surface Expression of Two T Cell Receptor (TCR)-β Chains, but Less Efficient Inhibition of Endogeneous Vβ→ (D)Jβ Rearrangements in the Presence of a Functional TCR-β Transgene

Journal of Experimental Medicine ◽

10.1084/jem.186.5.767 ◽

1997 ◽

Vol 186 (5) ◽

pp. 767-775 ◽

Cited By ~ 35

Author(s):

Anna Krotkova ◽

Harald von Boehmer ◽

Hans Jörg Fehling

Keyword(s):

T Cell ◽

Cell Surface ◽

T Cell Receptor ◽

Cell Receptor ◽

Surface Expression ◽

Cell Surface Expression ◽

Allelic Exclusion ◽

Thymocyte Development ◽

Β Chain ◽

Deficient Mice

Although individual T lymphocytes have the potential to generate two distinct T cell receptor (TCR)-β chains, they usually express only one allele, a phenomenon termed allelic exclusion. Expression of a functional TCR-β chain during early T cell development leads to the formation of a pre-T cell receptor (pre-TCR) complex and, at the same developmental stage, arrest of further TCR-β rearrangements, suggesting a role of the pre-TCR in mediating allelic exclusion. To investigate the potential link between pre-TCR formation and inhibition of further TCR-β rearrangements, we have studied the efficiency of allelic exclusion in mice lacking the pre-TCR-α (pTα) chain, a core component of the pre-TCR. Staining of CD3+ thymocytes and lymph node cells with antibodies specific for Vβ6 or Vβ8 and a pool of antibodies specific for most other Vβ elements, did not reveal any violation of allelic exclusion at the level of cell surface expression. This was also true for pTα-deficient mice expressing a functionally rearranged TCR-β transgene. Interestingly, although the transgenic TCR-β chain significantly influenced thymocyte development even in the absence of pTα, it was not able to inhibit fully endogeneous TCR-β rearrangements either in total thymocytes or in sorted CD25+ pre-T cells of pTα−/− mice, clearly indicating an involvement of the pre-TCR in allelic exclusion.

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The NITY motif of the beta-chain cytoplasmic domain is involved in stimulated internalization of the beta3 integrin A isoform

Journal of Cell Science ◽

10.1242/jcs.114.6.1101 ◽

2001 ◽

Vol 114 (6) ◽

pp. 1101-1113

Author(s):

M. Gawaz ◽

F. Besta ◽

J. Ylanne ◽

T. Knorr ◽

H. Dierks ◽

...

Keyword(s):

Steady State ◽

Cell Surface ◽

Molecular Mechanisms ◽

Chinese Hamster Ovary Cells ◽

Surface Expression ◽

Cytoplasmic Domain ◽

Cell Surface Expression ◽

Beta Chain ◽

Single Chain ◽

Beta3 Integrin

Beta3 integrin adhesion molecules play important roles in wound repair and the regulation of vascular development and three beta3 integrin isoforms (beta3-A, -B, -C) have been described so far. Surface expression of beta3 integrins is dynamically regulated through internalization of beta3 integrins, however, the molecular mechanisms are understood incompletely. To evaluate the role of the cytoplasmic domain of beta3 integrins for internalization, we have generated single chain chimeras with variant and mutated forms of beta3 cytoplasmic domains. Upon transient transfection into chinese hamster ovary cells, it was found that the beta3-A chimera had strongly reduced cell surface expression compared with the corresponding beta3-B, or beta3-C fusion proteins, or the tail-less constructs, whereas steady state levels of all chimeras were near identical. Studies employing cytoplasmic domain mutants showed that the NITY motif at beta3-A 756–759 is critical for plasma membrane expression of beta3-A. Furthermore, delivery of beta3-A to the cell surface was specifically modulated by the cytoplasmic protein beta3-endonexin, a previously described intracellular protein. Coexpression of the native, long form of beta3-endonexin, which does not interact with the beta3 tail, acted as a dominant negative inhibitor of beta3-A-internalization and enhanced steady-state surface expression of the beta3-A-chimera. Furthermore, anti-beta3 antibody-induced internalization of the native beta3 integrin (alpha(IIb)beta3 was dramatically reduced for the Tyr(759)-Ala substitution mutant (alpha(IIb)beta3) (Y759A) and expression of the long isoform of beta3-endonexin substantially decreased the internalization of wild-type alpha(IIb)beta3. Thus, the NITY motif of the beta-chain cytoplasmic domain is involved in stimulated internalization of the beta3 integrin A isoform and beta3-endonexin appears to couple the beta3-A isoform to a specific receptor-recycling pathway.

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LMP2-Specific TCR Gene Therapy for Hodgkin Lymphoma - Design of a Dominant TCR Construct for Immunotherapy.

Blood ◽

10.1182/blood.v110.11.2762.2762 ◽

2007 ◽

Vol 110 (11) ◽

pp. 2762-2762

Author(s):

Daniel P. Hart ◽

Sharyn Thomas ◽

Shao-an Xue ◽

Emma C. Morris ◽

Hans J. Stauss

Keyword(s):

T Cells ◽

Cell Surface ◽

Hodgkin Lymphoma ◽

Surface Expression ◽

Cell Surface Expression ◽

Beta Chain ◽

Antigen Specificity ◽

Human T Cells ◽

Beta Chain Genes ◽

Tcr Gene Therapy

Abstract Hodgkin lymphoma (HL) is the second most commonly diagnosed cancer in the 15–29 year old population. EBV-positive Hodgkin lymphoma typically demonstrates latency II antigen expression, characterised by loss of most EBV antigens except for the latent membrane protein (LMP) 1 and 2 and the EBNA-1 protein. LMP2 is expressed in Reed Sternberg cells and may serve as a target for antigen-specific immunotherapy. However, LMP2 is poorly immunogenic and it is often difficult to generate autologous LMP2-specific cytotoxic T lymphocytes (CTL) for adoptive immunotherapy. T cell receptor (TCR) gene transfer using retroviral vectors containing the TCR alpha and beta chain genes can reproducibly redirect the antigen specificity of a given population of T cells. Such an approach has been used here to generate LMP2-specific CTL independent of the immuno-competence of the patient. The goal of this study was to generate a retroviral TCR construct suitable for rapid and efficient production of LMP2-specific CTL. Retrovirally introduced TCRs compete with endogenous TCRs for a limited pool of CD3 molecules required for assembly of the TCR complex. Competition for CD3 molecules may limit surface expression of the introduced TCR resulting in a transduced T cell with poor functional avidity. In an attempt to generate a ‘highly competitive’ LMP2-TCR the following modifications were made to the retroviral vector construct: nucleotide sequences were codon optimised for efficient translation in human cells; the TCR chain constant regions were altered to contain murine sequences to enhance CD3 binding; and the TCR alpha and beta chain genes were linked by a self-cleaving 2A sequence from the porcine teschovirus to enhance equimolar expression of both TCR chains. The unmodified HLA-A2-restricted LMP2-specific TCR was poorly expressed in primary human T cells, suggesting that it competed inefficiently with endogenous TCR chains for cell surface expression. Very few CD8+Vβ13+ T cells were detectable after LMP2-TCR transduction (up to 2.5% of viable CD3+ T cells, as detected by FACs analysis using monoclonal anti-Vβ13 antibodies), which included 1.9% CD8+ T cells expressing endogenous Vβ13+ TCRs as quantified in mock-transduced control cells. Poor expression of the wild type LMP2-TCR was consistently observed in independent transduction experiments. However, transduction with the modified LMP2-TCR construct resulted in cell surface expression of the TCR in 55–65% viable CD3+ T cells. HLA-A2/LMP2 pentamer binding was demonstrated in 36–39% CD8+ CTL cells immediately post transduction. The transduced cells showed peptide-specific IFNγ and IL2 production and killed target cells displaying the LMP2 peptide. Of major importance, expression of the introduced LMP2-TCR completely suppressed the cell surface expression of almost the entire repertoire of endogenous TCR combinations, including ‘mis-paired’ TCRs in the transduced primary human T cells. ‘Mis-paired’ TCRs contain an introduced alpha chain paired with an endogenous beta chain and vice versa. The antigen specificity of such mispaired TCRs generated after transduction is unknown and could lead to unwanted side effects. The design of vectors containing modified TCR sequences, which produce ‘dominant’ TCRs may improve the efficacy of TCR gene therapy and reduce the risk of potential auto-reactivity of endogenous and ‘mis-paired’ TCR combinations. We have shown that LMP2-specific T cells can be readily generated by TCR gene transfer with minimal risk of autoreactivity.

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Regulation of thymocyte development through CD3. II. Expression of T cell receptor beta CD3 epsilon and maturation to the CD4+8+ stage are highly correlated in individual thymocytes.

Journal of Experimental Medicine ◽

10.1084/jem.178.6.1867 ◽

1993 ◽

Vol 178 (6) ◽

pp. 1867-1875 ◽

Cited By ~ 43

Author(s):

C N Levelt ◽

R Carsetti ◽

K Eichmann

Keyword(s):

Signal Transduction ◽

T Cell ◽

T Cell Receptor ◽

Alternative Hypothesis ◽

Cell Receptor ◽

Surface Expression ◽

Beta Chain ◽

Thymocyte Development ◽

Double Positive ◽

Highly Correlated

Recent studies have shown that maturation of CD4-8- double negative (DN) thymocytes to the CD4+8+ double positive (DP) stage is dependent on expression of the T cell receptor (TCR)-beta polypeptide. The exact mechanism by which the TCR-beta chain regulates this maturation step remains unknown. Previous experiments had suggested that in the presence of some TCR+ thymocytes, additional DN thymocytes not expressing a TCR-beta chain may be recruited to mature to the DP stage. The recent demonstration of an immature TCR-beta-CD3 complex on early thymocytes lead to the alternative hypothesis that signal transduction through an immature TCR-CD3 complex may induce maturation to the DP stage. In the latter case, maturation to the DP stage would depend on the expression of TCR-beta-CD3 in the same cell. We examined these two hypotheses by studying the expression of the intra- and extracellular CD3 epsilon, CD3 zeta, and TCR-beta polypeptides in intrathymic subpopulations during embryogenesis. CD3 epsilon and CD3 zeta were expressed intracellularly 2 and 1 d, respectively, before intracellular expression of the TCR-beta chain, potentially allowing immediate surface expression of an immature TCR-beta-CD3 complex as soon as functional rearrangement of a TCR-beta gene locus has been accomplished. Calcium mobilization could be induced by stimulation with anti-CD3 epsilon mAb as soon as intracellular TCR-beta was detectable, suggesting that a functional TCR-beta-CD3 complex is indeed expressed on the surface of early thymocytes. From day 17 on, most cells were in the DP stage, and over 95% of the DP cells expressed on the TCR-beta chain intracellularly. At day 19 of gestation, extremely low concentrations of TCR-beta chain and CD3 epsilon were detectable on the cell surface of nearly all thymocytes previously thought to be TCR-CD3 negative. These findings strongly support the hypothesis that maturation to the DP stage depends on surface expression of and subsequent signal transduction through an immature TCR-beta-CD3 complex and suggest that maturation to the DP stage by recruitment, if it occurs at all, is of minor relevance.

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Fc gamma RII/III and CD2 expression mark distinct subpopulations of immature CD4-CD8- murine thymocytes: in vivo developmental kinetics and T cell receptor beta chain rearrangement status.

Journal of Experimental Medicine ◽

10.1084/jem.177.4.1079 ◽

1993 ◽

Vol 177 (4) ◽

pp. 1079-1092 ◽

Cited By ~ 68

Author(s):

H R Rodewald ◽

K Awad ◽

P Moingeon ◽

L D'Adamio ◽

D Rabinowitz ◽

...

Keyword(s):

T Cell ◽

T Cell Receptor ◽

Fetal Development ◽

Cell Receptor ◽

Surface Expression ◽

Cell Surface Expression ◽

Immunoglobulin Gene ◽

Beta Chain ◽

Double Positive ◽

Alpha Beta

We have recently identified a dominant wave of CD4-CD8- (double-negative [DN]) thymocytes in early murine fetal development that express low affinity Fc gamma receptors (Fc gamma RII/III) and contain precursors for Ti alpha/beta lineage T cells. Here we show that Fc gamma RII/III is expressed in very immature CD4low single-positive (SP) thymocytes and that Fc gamma RII/III expression is downregulated within the DN subpopulation and before the CD3-CD8low SP stage in T cell receptor (TCR)-alpha/beta lineage-committed thymocytes. DN Fc gamma RII/III+ thymocytes also contain a small fraction of TCR-gamma/delta lineage cells in addition to TCR-alpha/beta progenitors. Fetal day 15.5 DN TCR-alpha/beta lineage progenitors can be subdivided into three major subpopulations as characterized by cell surface expression of Fc gamma RII/III vs. CD2 (Fc gamma RII/III+CD2-, Fc gamma RII/III+CD2+, Fc gamma RII/III-CD2+). Phenotypic analysis during fetal development as well as adoptive transfer of isolated fetal thymocyte subpopulations derived from C57B1/6 (Ly5.1) mice into normal, nonirradiated Ly5.2 congenic recipient mice identifies one early differentiation sequence (Fc gamma RII/III+CD2(-)-->Fc gamma RII/III+CD2(+)-->Fc gamma RII/III-CD2+) that precedes the entry of DN thymocytes into the CD4+CD8+ double-positive (DP) TCRlow/- stage. Unseparated day 15.5 fetal thymocytes develop into DP thymocytes within 2.5 d and remain at the DP stage for > 48 h before being selected into either CD4+ or CD8+ SP thymocytes. In contrast, Fc gamma RII/III+CD2- DN thymocytes follow this same developmental pathway but are delayed by approximately 24 h before entering the DP compartment, while Fc gamma RII/III-CD2+ display accelerated development by approximately 24 h compared with total day 15.5 thymocytes. Fc gamma RII/III-CD2+ are also more developmentally advanced than Fc gamma RII/III+CD2- fetal thymocytes with respect to their TCR beta chain V(D)J rearrangement. At day 15.5 in gestation, beta chain V(D)J rearrangement is mostly, if not entirely, restricted to the Fc gamma RII/III-CD2+ subset of DN fetal thymocytes. Consistent with this analysis in fetal thymocytes, > 90% of adult thymocytes derived from mice carrying a disrupting mutation at the recombination-activating gene 2 locus (RAG-2-/-) on both alleles are developmentally arrested at the DN CD2- stage. In addition, there is a fivefold increase in the relative percentage of thymocytes expressing Fc gamma RII/III in TCR and immunoglobulin gene rearrangement-incompetent homozygous RAG-2-/- mice (15% Fc gamma RII/III+) versus rearrangement-competent heterozygous RAG-2+/- mice (< 3% Fc gamma RII/III+). Thus, Fc gamma RII/III expression defines an early DN stage preceding V beta(D beta)I beta rearrangement, which in turn is followed by surface expression of CD2. Loss of Fc gamma RII/III and acquisition of CD2 expression characterize a late DN stage immediately before the conversion into DP thymocytes.

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Independent association of T cell receptor beta and gamma chains with CD3 in the same cell.

Journal of Experimental Medicine ◽

10.1084/jem.166.2.595 ◽

1987 ◽

Vol 166 (2) ◽

pp. 595-600 ◽

Cited By ~ 21

Author(s):

F Koning ◽

W L Maloy ◽

D Cohen ◽

J E Coligan

Keyword(s):

Cell Surface ◽

Cell Line ◽

T Cell Receptor ◽

Cell Receptor ◽

Beta Chain ◽

Gamma Chain ◽

Chain Complexes ◽

T Cell Receptor Beta ◽

Independent Association ◽

Receptor Beta

We have demonstrated that the PEER cell line, which expresses a CD3-associated TCR gamma chain on the cell surface, synthesizes TCR beta chain intracellularly. A percentage of this TCR beta chain associates with the CD3 complex intracellularly. These results indicate that TCR beta and gamma chains can be synthesized by one cell line, and that these chains can independently associate with the CD3 complex. However, the results argue against the formation of TCR beta gamma chain complexes in this cell line.

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Protein Phosphatase 2A Isotypes Regulate Cell Surface Expression of the T Cell Receptor

Experimental and Clinical Immunogenetics ◽

10.1159/000049084 ◽

2001 ◽

Vol 18 (1) ◽

pp. 24-33 ◽

Cited By ~ 5

Author(s):

Jens Peter H. Lauritsen ◽

Charlotte Menné ◽

Jesper Kastrup ◽

Jes Dietrich ◽

Carsten Geisler

Keyword(s):

T Cell ◽

Cell Surface ◽

T Cell Receptor ◽

Protein Phosphatase ◽

Protein Phosphatase 2A ◽

Cell Receptor ◽

Surface Expression ◽

Cell Surface Expression ◽

Phosphatase 2A

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Interleukin 2 receptor gamma chain expression on resting and activated lymphoid cells.

Journal of Experimental Medicine ◽

10.1084/jem.180.1.241 ◽

1994 ◽

Vol 180 (1) ◽

pp. 241-251 ◽

Cited By ~ 76

Author(s):

T Nakarai ◽

M J Robertson ◽

M Streuli ◽

Z Wu ◽

T L Ciardelli ◽

...

Keyword(s):

T Cells ◽

Cell Surface ◽

Nk Cells ◽

Interleukin 2 ◽

Surface Expression ◽

Cell Surface Expression ◽

Beta Chain ◽

Gamma Chain ◽

Affinity Receptor ◽

Low Levels

The interleukin 2 receptor (IL-2R) is known to be comprised of at least three genetically distinct subunits termed alpha, beta, and gamma. These chains can be expressed individually or in various combinations resulting in distinct receptors with different affinities for IL-2. In contrast to alpha and beta, the cell surface expression of the gamma chain protein previously has not been well-characterized. To examine cell surface expression of IL-2R gamma on hematopoietic cells, we developed two new monoclonal antibodies (mAbs) specific for this protein. Both 1A11 (immunoglobulin [IgG1]) and 3G11 (IgM) specifically reacted with murine cells transfected with IL-2R gamma cDNA, and immunoprecipitation studies indicated that both antibodies precipitated a protein of approximately 62-65 kD. Scatchard analysis of IL-2 binding to murine cells transfected with cDNA-encoding combinations of IL-2R components demonstrated that neither beta nor gamma chain bind IL-2 with measurable affinity, but coexpression of both beta and gamma is sufficient to form an intermediate affinity receptor. In the absence of gamma chain, beta chain interacts with alpha chain to form a "pseudo-high" affinity receptor. In contrast, gamma chain does not appear capable of interacting with alpha in the absence of beta chain. Thus, gamma chain appears to interact only with beta, but beta chain is capable of interacting with both alpha and gamma. Using the newly developed mAbs to examine cell surface expression by immunofluorescence, resting T cells were found to express low levels of gamma chain without detectable alpha or beta. Early after mitogen stimulation, T cells expressed higher levels of alpha, beta, and gamma. However, at later time points, T cells expressed alpha and gamma in marked excess over beta. Thus, formation of high affinity IL-2R on activated T cells was primarily limited by beta chain expression. In contrast, resting natural killer (NK) cells constitutively expressed IL-2R beta without detectable alpha or gamma. After activation with either IL-2 or IL-12, expression of both alpha and gamma transiently increased and then returned to very low levels. Expression of functional IL-2R on resting and activated NK cells, therefore, appeared to be primarily limited by the expression of gamma chain. IL-2 binding studies with resting NK cells confirmed the results of immunofluorescence studies indicating the presence of very low numbers of intermediate affinity (beta gamma) receptors for IL-2 on these cells.(ABSTRACT TRUNCATED AT 400 WORDS)

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