scholarly journals Intrathymic nurse cell lymphocytes can induce a specific graft-versus-host reaction.

1990 ◽  
Vol 172 (2) ◽  
pp. 521-529 ◽  
Author(s):  
J Penninger ◽  
K Hála ◽  
G Wick
Keyword(s):  
T Cell ◽  
Peripheral Blood Lymphocytes ◽  
Graft Versus Host Reaction ◽  
Gamma Delta ◽  
Serial Transfer ◽  
Graft Versus Host ◽  
Alpha Beta ◽  
A Minor ◽  
Delta Cells ◽  
Gamma Delta Cells

Single chicken thymic nurse cells (TNC) placed onto the chorionallantoic membrane (CAM), showed that intra-TNC lymphocytes (TNC-L) possess a strong graft-versus-host reactivity (GVHR) in allogeneic MHC combinations. This reaction shows the morphological, phenotypic, and functional characteristics of a classical GVH reaction (GVHR). The induction of a GVHR was significantly higher for TNC-L as compared with thymocytes or peripheral blood lymphocytes (PBL). The specificity of the GVHR was shown by serial transfer experiments onto appropriate allogeneic and syngeneic secondary embryonic hosts. In immunofluorescence analyses with monoclonal antibodies (mAb) to the chicken alpha/beta and gamma/delta T cell receptors (TCR) and the CD3, CD4, and CD8 equivalents, an enrichment of CD3+/CD4+/CD8- and CD3+/CD-4-/CD8+, TCR-alpha/beta + and TCR- gamma/delta + cells was observed inside TNC as compared with extra-TNC thymocytes. A large proportion of CD4+ and/or CD8+ TCR- gamma/delta + cells were demonstrated inside TNC. A minor population among TCR- gamma/delta extra-TNC thymocytes also expressed CD4 and/or CD8 molecules. Based on functional tests and double staining experiments, we propose that CD4+/CD8+ thymocytes enter the TNC where they may undergo positive selection for MHC restriction and further differentiation to CD4 or CD8 single-positive cells. Taken together these data support the concept that TNC contribute a specialized thymic microenvironment for T cell differentiation and maturation.

scholarly journals Murine gamma/delta-expressing T cells affect alloengraftment via the recognition of nonclassical major histocompatibility complex class Ib antigens

Blood ◽  
1996 ◽  
Vol 87 (10) ◽  
pp. 4463-4472 ◽  
Author(s):  
BR Blazar ◽  
PA Taylor ◽  
JA Bluestone ◽  
DA Vallera
Keyword(s):  
T Cells ◽  
Major Histocompatibility Complex ◽  
T Cell ◽  
Graft Rejection ◽  
Gene Products ◽  
Gamma Delta ◽  
Histocompatibility Complex ◽  
Alpha Beta ◽  
Delta Cells ◽  
Gamma Delta Cells

T cells with antidonor specificities have been isolated from human recipients experiencing graft rejection after allogeneic bone marrow transplantation (BMT). Partial T-cell depletion of unrelated BM grafts with an anti- T-cell receptor (TCR) monoclonal antibody (MoAb) directed against the TCR alpha/beta heterodimer have shown that the incidence of graft-versus-host disease is low and that the incidence of durable engraftment is high. These studies suggest either that the number of residual TCR alpha/beta+ cells was sufficient to permit alloengraftment or that the preservation of cells other than TCR alpha/beta+ cells was beneficial for engraftment. With respect to the latter, one such candidate cell is the TCR gamma/delta+ T cell. Because no studies have specifically examined whether TCR gamma/delta+ cells might be capable of eliminating BM-derived hematopoietic cells, we established a new graft rejection model system in which transgenic (Tg) H-2d mice (termed G8), known to express gamma/delta heterodimers on high proportion of peripheral T cells, were used as BMT recipients. These Tg TCR gamma/delta+ cells respond vigorously to target cells that express the nonclassical major histocompatibility complex (MHC) class lb region gene products encoded in H-2T region of H-2T(b)+ strains. G8 Tg mice were used as recipients for C57BL/6 (B6: H-2(b); H-2T(b)) T-cell- depleted (TCD) donor BM. We show that G8 Tg (H-2(d), H-2T(d)) mice are potent mediators of B6 BM graft rejection and that the rejection process was inhibited by anti-TCR gamma/delta MoAbs. In contrast, BM from a B6 congenic strain that expresses the H-2T(a) allele, B6.A- Tl(a)/BoyEg, was readily accepted, suggesting that H-2T antigens on repopulating donor BM cells are the targets of host graft rejecting T cells that express the TCR gamma/delta heterodimer. PB chimerism studies were performed at > or = 1.5 months post-BMT using TCD BM from severe combined immunodeficient allogeneic donors, which is highly susceptible to rejection by the host. The addition of donor G8 TCR gamma/delta+ cells to TCD donor BM was shown to significantly increase alloengraftment in B6 recipients. These results show that (1) host TCR gamma/delta+ cells can reject repopulating donor cells, presumably by responding to nonclassical MHC class lb gene products expressed on BM- derived hematopoietic progenitor cells; and (2) donor TCR gamma/delta+ cells can facilitate the alloengraftment of rigorously TCD donor BM.

scholarly journals A role for interleukin 4 in the differentiation of mature T cell receptor gamma/delta + cells from human intrathymic T cell precursors.

1990 ◽  
Vol 172 (2) ◽  
pp. 439-446 ◽  
Author(s):  
A Bárcena ◽  
M L Toribio ◽  
L Pezzi ◽  
C Martínez
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Critical Role ◽  
Cell Receptor ◽  
Interleukin 4 ◽  
Gamma Delta ◽  
Consistent Finding ◽  
Delta Cells ◽  
Gamma Delta Cells

We have analyzed the effect of human recombinant interleukin 4 (rIL-4) on the growth and differentiation of human intrathymic pre-T cells (CD7+2+1-3-4-8-). We describe that this population of T cell precursors proliferates in response to rIL-4 (in the absence of mitogens or other stimulatory signals) in a dose-dependent way. The IL-4-induced proliferation is independent of the IL-2 pathway, as it cannot be inhibited with an anti-IL-2 receptor alpha chain antibody. In our culture conditions, rIL-4 also promotes the differentiation of pre-T cells into phenotypically mature T cells. Although both CD3/T cell receptor (TCR)-alpha/beta + and CD3-gamma/delta + T cells were obtained, the preferential differentiation into TCR-gamma/delta + cells was a consistent finding. These results suggest that, in addition to IL-2, IL-4 plays a critical role in promoting growth and differentiation of intrathymic T cell precursors at early stages of T cell development.

scholarly journals Differential effects of interleukin-15 and interleukin-2 on differentiation of bipotential T/natural killer progenitor cells.

1996 ◽  
Vol 184 (2) ◽  
pp. 325-336 ◽  
Author(s):  
G Leclercq ◽  
V Debacker ◽  
M de Smedt ◽  
J Plum
Keyword(s):  
Nk Cells ◽  
Progenitor Cells ◽  
Cell Number ◽  
Gamma Delta ◽  
Fetal Thymus ◽  
Low Concentrations ◽  
Alpha Beta ◽  
High Concentrations ◽  
Delta Cells ◽  
Gamma Delta Cells

Bipotential T/natural killer (NK) progenitor cells are destined to differentiate mainly into T cell receptor (TCR) alpha beta and TCR gamma delta cells in a thymic microenvironment, whereas extrathymically they selectively develop into NK cells. The exact environmental conditions that are required for differentiation into these three leukocyte populations are largely unknown. In this report, we have investigated and compared the effect of interleukin (IL)-15 and IL-2 in this process. The IL-15 receptor is composed of the gamma and beta chains of the IL-2 receptor (IL-2R gamma and IL-2R beta) and of a specific alpha chain (IL-15R alpha). Here, it is shown that IL-15 mRNA is mainly expressed in thymic epithelial stromal cells, whereas IL-2 mRNA is exclusively expressed in thymocytes. IL-2R beta-expressing cells were present in the fetal thymus with a CD25-CD44+Fc gamma R+HSA-/low TCR- phenotype, which is characteristic of progenitor cells. These cells also expressed IL-15R alpha messenger RNA. Sorted IL-2R beta + TCR- cells differentiated into TCR alpha beta and TCR gamma delta cells after transfer to alymphoid thymic lobes, whereas culture of the same sorted cells in cell suspension in the presence of IL-15 resulted in the generation of functional NK cells. This shows that IL-2R beta +TCR- cells of the fetal thymus contain bipotential T/NK progenitors. Addition of low concentrations of IL-15 to fetal thymic organ culture (FTOC) resulted in an increase of all T cell subpopulations. The largest expansion occurred in the TCR gamma delta compartment. In contrast, low concentrations of IL-2 did not result in a higher total cell number and did not induce outgrowth of TCR gamma delta cells. High concentrations of IL-15 blocked TCR alpha beta development and shifted differentiation towards NK cells. Differentiation towards TCR gamma delta cells still proceeded. High concentrations of IL-2 similarly induced development into NK cells, but the cell number was fourfold lower than in IL-15 cultures. Importantly, blocking of IL-2R alpha in IL-2-treated FTOC resulted in a drastic increase in cell number, indicating that IL-2R alpha negatively regulates cell expansion. Collectively, these experiments provide direct evidence that IL-15 and IL-2 differentially affect the differentiation of bipotential T/NK progenitors.

scholarly journals Involvement of the interleukin 2 pathway in the rearrangement and expression of both alpha/beta and gamma/delta T cell receptor genes in human T cell precursors.

1988 ◽  
Vol 168 (6) ◽  
pp. 2231-2249 ◽  
Author(s):  
M L Toribio ◽  
A de la Hera ◽  
J Borst ◽  
M A Marcos ◽  
C Márquez ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Interleukin 2 ◽  
Cell Receptor ◽  
Beta Chain ◽  
Gamma Delta ◽  
Human T Cell ◽  
Alpha Beta ◽  
A Minor

In this report, we have undertaken the phenotypic, functional and molecular characterization of a minor (less than 5%) subpopulation of adult thymocytes regarded as the earliest intrathymic T-cell precursors. Pro-T cells were immunoselected and shown to express different hematopoietic cell markers (CD45, CD38, CD7, CD5) and some activation-related molecules (4F2, Tr, HLA class II), but lack conventional T cell antigens (CD2-1-3-4-8-). TCR-gamma RNA messages are already expressed at this early ontogenic stage, while alpha and beta chain TCR genes remain in germline configuration. In vitro analyses of the growth requirements of pro-T cells demonstrated the involvement of the IL-2 pathway in promoting their proliferation and differentiation into CD3+ CD4+ or CD8+ mature thymocytes. Moreover, during the IL-2-mediated maturation process rearrangements and expression of both alpha and beta chain TCR genes occurred, and resulted in the acquisition of alpha/beta as well as gamma/delta (either disulphide-linked or non-disulphide-linked) heterodimeric TCR among the pro-T cell progeny.

scholarly journals Constitutive expression of a groEL-related protein on the surface of human gamma/delta cells.

1990 ◽  
Vol 172 (6) ◽  
pp. 1857-1860 ◽  
Author(s):  
W Jarjour ◽  
L A Mizzen ◽  
W J Welch ◽  
S Denning ◽  
M Shaw ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Stress Proteins ◽  
Stress Protein ◽  
Constitutive Expression ◽  
Target Antigen ◽  
Exact Nature ◽  
Gamma Delta ◽  
Delta Cells ◽  
Gamma Delta Cells

Rabbit antibodies to hsp58 (P1), the human homologue of the Escherichia coli stress protein groEL, react specifically in indirect immunofluorescence and complement-dependent microcytoxicity experiments with a cell surface antigen expressed constitutively by T cell lines bearing gamma/delta receptors. This anti-hsp58-reactive antigen is not demonstrable on T cells that express alpha/beta receptors or on various cells that lack T cell receptors. Certain evidence was obtained to suggest that the target antigen on the surface of gamma/delta T cells is a approximately 77-kD protein distinct from intracellular hsp58 and known members of the hsp70 stress protein family. While the exact nature and significance of this anti-hsp58-reactive protein remain to be determined, these data may help to clarify the roles of groEL-related stress proteins and gamma/delta cells that recognize groEL homologous in immunologic defense against infection and in autoimmune disease.

scholarly journals Selective outgrowth of CD45RO+ V gamma 9+/V delta 2+ T-cell receptor gamma/delta T cells early after bone marrow transplantation

Blood ◽  
1991 ◽  
Vol 78 (7) ◽  
pp. 1875-1881 ◽  
Author(s):  
D van der Harst ◽  
A Brand ◽  
SA van Luxemburg-Heijs ◽  
YM Kooij-Winkelaar ◽  
FE Zwaan ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Mononuclear Cells ◽  
Cell Receptor ◽  
Gamma Delta T Cells ◽  
Gamma Delta ◽  
Delta Cells ◽  
Selective Outgrowth ◽  
Gamma Delta Cells

Before and after bone marrow transplantation (BMT) for hematologic malignancies, peripheral blood mononuclear cells from 10 patients were obtained. The relative and absolute numbers of CD3+ T-cell receptor gamma delta+ (TCR gamma delta+) cells, as defined by the reaction of monoclonal antibodies (MoAbs) directed against CD3 and the TCR gamma delta (anti-TCR gamma delta-1), were determined. Before transplantation, eight of nine patients tested had less than 10% CD3+TCR gamma delta+ cells. Consistent increased numbers of gamma delta cells up to eightfold the pretransplant level can be seen in four of nine patients tested within the first 4 months after BMT. The large majority of early posttransplant gamma delta and alpha beta T cells express the CD45RO antigen, which is usually expressed on “memory” cells only. The V-region usage of the TCR gamma delta+ T cells was analyzed using fresh mononuclear cells and MoAbs against known V gamma and V delta regions. For more detailed analysis, CD3+TCR gamma delta+ cells were sorted and cultured in bulk and cloned. Using fresh cells and bulk cultures, mainly V gamma 9+V delta 1-V delta 2+ cells were found during engraftment. Only after 6 weeks post-BMT, V gamma 9-V delta 1+V delta 2- cells appear. Analysis of the V gamma and V delta usage at the clonal level confirmed the observation that early after BMT only V gamma 9+V delta 2+ cells are present, whereas gamma delta T- cell clones expressing other gamma delta TCR phenotypes can only be detected 4 to 6 weeks post-BMT. The predominance of V gamma 9+ cells during early engraftment could be explained by several mechanisms: (A) sequential rearrangements during T-cell development, leading to an early wave of V gamma 9+ cells, or (B) selective outgrowth of preexisting V gamma 9+V delta 2+CD45RO+ TCR gamma delta cells in the bone marrow graft, possibly as a result of antigen driven expansion due to exposure to environmental antigens.

scholarly journals Lethal murine graft-versus-host disease induced by donor gamma/delta expressing T cells with specificity for host nonclassical major histocompatibility complex class Ib antigens

Blood ◽  
1996 ◽  
Vol 87 (2) ◽  
pp. 827-837 ◽  
Author(s):  
BR Blazar ◽  
PA Taylor ◽  
A Panoskaltsis-Mortari ◽  
TA Barrett ◽  
JA Bluestone ◽  
...  
Keyword(s):  
T Cells ◽  
Gene Products ◽  
Mhc Class Ib ◽  
Gamma Delta ◽  
Graft Versus Host ◽  
Histocompatibility Complex ◽  
Delta Cell ◽  
Delta Cells ◽  
Class Ib ◽  
Gamma Delta Cells

Although T-cell receptor (TCR) alpha/beta expressing cells have a well- known role in graft-versus-host disease (GVHD) generation, the role of TCR gamma/delta expressing cells in this process has remained unclear. To elucidate the potential function of TCR gamma/delta cells in GVHD, we have used transgenic (Tg) H-2d mice (termed G8) that express gamma/delta heterodimers on a high proportion of peripheral T cells. In vitro, G8 Tg gamma/delta T cells proliferate to and kill C57BL/6 (B6) (H-2b) which express gene products (T10b and T22b) from the nonclassical major histocompatibility complex (MHC) class Ib H-2T region. The infusion of G8 Tg (H-2Td) TCR gamma/delta cells into lethally irradiated [900 cGy total body irradiation (TBI)] B6 (H-2b) mice resulted in the generation of lethal GVHD characterized histologically by destruction of the spleen, liver, lung, and colon. Lethal GVHD was prevented by the injection of anti-TCR gamma/delta monoclonal antibodies. Immunohistochemical analysis of B6 recipients post-bone marrow transplantation (BMT) confirmed that G8 Tg TCR gamma/delta cells infiltrated GVHD target tissues (skin, liver, colon, and lung) and were absent in recipients treated with anti-TCR gamma/delta monoclonal antibodies (MoAbs) but not anti-CD4 plus anti- CD8 MoAbs. In contrast, injection of TCR gamma/delta+ cells into irradiated (900 cGy TBI) B6.A-TIaa BoyEg mice that do not express either T10b or T22b did not induce lethal GVHD. Similarly, in a different GVHD system in which sublethal irradiation without bone marrow (BM) rescue was used, B6 but not B6.A-TIaa/BoyEg mice were found to be susceptible to TCR gamma delta+ cell mediated GVHD-induced lethality characterized by an aplasia syndrome. These results demonstrate that TCR gamma/delta cells have the capacity to cause acute lethal GVHD in mice and suggest that nonclassical MHC class Ib gene products expressed on GVHD target organs are responsible for G8 Tg TCR gamma/delta+ cell mediated lethality.

scholarly journals Selective outgrowth of CD45RO+ V gamma 9+/V delta 2+ T-cell receptor gamma/delta T cells early after bone marrow transplantation

Blood ◽  
1991 ◽  
Vol 78 (7) ◽  
pp. 1875-1881 ◽  
Author(s):  
D van der Harst ◽  
A Brand ◽  
SA van Luxemburg-Heijs ◽  
YM Kooij-Winkelaar ◽  
FE Zwaan ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Mononuclear Cells ◽  
Cell Receptor ◽  
Gamma Delta T Cells ◽  
Gamma Delta ◽  
Delta Cells ◽  
Selective Outgrowth ◽  
Gamma Delta Cells

Abstract Before and after bone marrow transplantation (BMT) for hematologic malignancies, peripheral blood mononuclear cells from 10 patients were obtained. The relative and absolute numbers of CD3+ T-cell receptor gamma delta+ (TCR gamma delta+) cells, as defined by the reaction of monoclonal antibodies (MoAbs) directed against CD3 and the TCR gamma delta (anti-TCR gamma delta-1), were determined. Before transplantation, eight of nine patients tested had less than 10% CD3+TCR gamma delta+ cells. Consistent increased numbers of gamma delta cells up to eightfold the pretransplant level can be seen in four of nine patients tested within the first 4 months after BMT. The large majority of early posttransplant gamma delta and alpha beta T cells express the CD45RO antigen, which is usually expressed on “memory” cells only. The V-region usage of the TCR gamma delta+ T cells was analyzed using fresh mononuclear cells and MoAbs against known V gamma and V delta regions. For more detailed analysis, CD3+TCR gamma delta+ cells were sorted and cultured in bulk and cloned. Using fresh cells and bulk cultures, mainly V gamma 9+V delta 1-V delta 2+ cells were found during engraftment. Only after 6 weeks post-BMT, V gamma 9-V delta 1+V delta 2- cells appear. Analysis of the V gamma and V delta usage at the clonal level confirmed the observation that early after BMT only V gamma 9+V delta 2+ cells are present, whereas gamma delta T- cell clones expressing other gamma delta TCR phenotypes can only be detected 4 to 6 weeks post-BMT. The predominance of V gamma 9+ cells during early engraftment could be explained by several mechanisms: (A) sequential rearrangements during T-cell development, leading to an early wave of V gamma 9+ cells, or (B) selective outgrowth of preexisting V gamma 9+V delta 2+CD45RO+ TCR gamma delta cells in the bone marrow graft, possibly as a result of antigen driven expansion due to exposure to environmental antigens.

scholarly journals Selection of rabbit CD4- CD8- T cell receptor-gamma/delta cells by in vitro transformation with human T lymphotropic virus-I.

1993 ◽  
Vol 178 (4) ◽  
pp. 1337-1345 ◽  
Author(s):  
S Sawasdikosol ◽  
B F Hague ◽  
T M Zhao ◽  
F S Bowers ◽  
R M Simpson ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Lines ◽  
Cell Receptor ◽  
Gamma Delta ◽  
T Lymphotropic Virus ◽  
T Cell Lines ◽  
Delta Cells ◽  
Selection Of ◽  
Gamma Delta Cells

In vitro transformation of rabbit peripheral blood mononuclear cells (PBMC) with human T lymphotropic virus-I (HTLV)-infected human or rabbit cells resulted in CD4- CD8- cell lines, some of which caused acute leukemia when injected into rabbits. Structural analyses of the proviruses from cell lines with diverse pathogenic effects provided no clear correlation with lethality. The rabbit lines were provisionally designated T cells because they express interleukin 2R (IL-2R) and CD5 and lack surface immunoglobulin, but none express functional T cell receptor (TCR) alpha or beta transcripts. A more detailed characterization of the HTLV-I-infected cells was required to determine cell lineage and its potential influence on pathogenic consequences. Probes for rabbit TCR gamma and delta genes were derived and used to detect gamma and delta TCR RNA transcripts, identifying the in vitro transformed lines as gamma/delta T cells. CD4+ and CD8+ lines were derived from PBMC of HTLV-I-infected rabbits and CD4+ TCR-alpha/beta HTLV-I lines were derived from rabbit thymus, eliminating the possibility that the HTLV-I isolates used here transform only CD4- CD8- TCR-gamma/delta cells. The percentage of gamma/delta cells in rabbit PBMC is relatively high (23% in adult rabbits); this with diminution of CD4+ and CD8+ cells in IL-2-supplemented PBMC or thymocyte cultures may account for selection of rabbit HTLV-I-infected gamma/delta T cell lines in vitro. The availability of well-characterized T cell lines with diverse in vivo effects in the rabbit HTLV-I disease model allows evaluation of roles played by cell type in HTLV-I-mediated disease.

scholarly journals Human lymphocytes bearing T cell receptor gamma/delta are phenotypically diverse and evenly distributed throughout the lymphoid system.

1989 ◽  
Vol 169 (4) ◽  
pp. 1277-1294 ◽  
Author(s):  
V Groh ◽  
S Porcelli ◽  
M Fabbi ◽  
L L Lanier ◽  
L J Picker ◽  
...  
Keyword(s):  
T Cell ◽  
Human Lymphocytes ◽  
Cell Receptor ◽  
The Body ◽  
Lymphoid Tissues ◽  
Gamma Delta ◽  
Cell Repertoire ◽  
Delta Cells ◽  
Small Subpopulation ◽  
Gamma Delta Cells

A direct quantitative and phenotypic cytofluorographic analysis of TCR-gamma/delta+ lymphocytes as well as an immunohistologic study of their tissue distribution and microanatomy was made possible by the availability of two mAbs (anti-TCR-delta 1 and anti-C gamma M1) specific for framework determinants on human TCR gamma and delta chains, respectively. TCR-gamma/delta+ lymphocytes, ranging between greater than 0.5 and 16% of CD3+ cells, were found in fetal and postnatal thymus, fetal and adult peripheral lymphoid organs, and adult peripheral blood. While TCR-gamma/delta+ lymphocytes comprised a small subpopulation of T cells (mean, approximately 4%) occasionally greater than 10-16% of CD3+ cells expressed TCR-gamma/delta. Virtually all TCR-gamma/delta+ thymocytes/lymphocytes expressed CD7, CD2, and CD5 but were heterogeneous with respect to their expression of CD1, CD4, CD8, CD28, CD11b, CD16, and Leu-7. Human TCR-gamma/delta+ cells populate both organized lymphoid tissues (thymus, tonsil, lymphnode, and spleen) as well as the gut- and skin-associated lymphoid systems at similar frequencies without obvious tropism for epithelial microenvironments. TCR-gamma/delta+ lymphocytes tend to be located within a given organ wherever TCR-alpha/beta+ lymphocytes are found. This study shows that TCR-gamma/delta+ lymphocytes constitute a small but numerically important, phenotypically diverse T cell population distributed throughout the body. These results support the concept that TCR-gamma/delta+ cells comprise a distinct, functionally heterogeneous, mature T cell sublineage that may substantially broaden the T cell repertoire at all immunologically relevant sites.

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