Androgen Modulates Thymopoiesis by Regulating Thymocyte Precursor Immigration.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1271-1271
Author(s):  
Kirsten M. Williams ◽  
Yu-Waye Chu ◽  
Ronald E. Gress
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Cd8 T Cells ◽  
Allogeneic Bone Marrow Transplantation ◽  
Allogeneic Bone ◽  
Male Mice ◽  
Recent Thymic Emigrants ◽  
Thymic Involution ◽  
Double Positive ◽  
Peripheral Cell

Abstract Impaired thymopoiesis contributes to immune deficiency in aging, AIDS, and following allogeneic bone marrow transplantation. However, little is known of the mechanisms of thymic regulation and the determinants of thymic function. Exogenous administration of testosterone and estrogen has been shown to accelerate thymic involution. Conversely, studies have demonstrated that castration of male mice resulted in increased thymic size and thymocyte number. We present data that thymic enlargement in castrated male mice is due to enhanced thymopoiesis. Comparing castrated post-pubertal male mice with age-matched control littermates, we found a statistically significant doubling of thymic weight, thymocyte number, and double-positive CD4+CD8+ thymocytes as early as eight days post-orchiectomy. Major thymocyte subsets defined as CD4− CD8−, CD4+CD8−, CD8+CD4− were also increased post castration and the ratio of subsets was unchanged suggesting that castration augmented overall thymic activity. This was further corroborated by a concomitant 4–6 fold increase in thymic T cell-receptor excision circles (TREC). Significantly, at one month post-castration, early thymic progenitors (Lin- CKIT hi CD44 hi) were increased threefold in the castrated cohort. The increase in thymic productivity led to a subsequent increase in peripheral cell populations, with a significant increase in splenic CD4+ and CD8+ T cells. The greatest proportion of this increase was due to naïve splenic CD4 and CD8 T cells total numbers as defined by CD44lo expression. Memory splenocytes, CD44hi CD4+ and CD8+ cells, were slightly increased as well. Additionally, there was an increase in the number of splenic recent thymic emigrants (RTE) as enumerated by TREC. Our data suggest that androgen withdrawal leads to an increase in thymopoiesis, as enumerated by a significant influx of ETPs, increased total thymic TREC, subsequent increases in single positive thymocytes, and increased peripheral recent thymic emigrants. Furthermore, the data suggest that a mechanism by which this occurs is through increased immigration of thymocyte precursors from the bone marrow into the thymus identifying this as a central point in thymic regulation.

scholarly journals Prediction of graft-versus-host disease by phenotypic analysis of early immune reconstitution after CD6-depleted allogeneic bone marrow transplantation

Blood ◽  
1993 ◽  
Vol 82 (7) ◽  
pp. 2216-2223 ◽  
Author(s):  
RJ Soiffer ◽  
R Gonin ◽  
C Murray ◽  
MJ Robertson ◽  
K Cochran ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Cd8 T Cells ◽  
Odds Ratio ◽  
Allogeneic Bone Marrow Transplantation ◽  
Allogeneic Bone Marrow ◽  
Allogeneic Bone ◽  
Cd8 Cells ◽  
Graft Versus Host ◽  
Marrow Infusion

Graft-versus-host disease (GVHD) is a major cause of morbidity and mortality following allogeneic bone marrow transplantation (BMT). Because GVHD is frequently refractory to treatment, the early identification of high-risk patients could have significant clinical value. To identify such patients, we examined early immunologic recovery in 136 patients with hematologic malignancies who received anti-T12 (CD6)-purged allogeneic bone marrow over a 9-year period. The majority of patients received marrow from HLA-matched sibling donors after ablation with cyclophosphamide and total body irradiation. No patients received any immune suppressive medications for GVHD prophylaxis. The fraction and absolute numbers of peripheral blood lymphocytes (PBL) expressing the CD3, CD4, CD8, and CD56 surface antigens were determined weekly by immunofluorescence analysis in patients beginning 8 to 14 days (week 2) after marrow infusion. Results in patients who did or did not subsequently develop GVHD post-BMT were compared. Within 2 weeks of marrow infusion, patients who developed grades 2–4 GVHD had significantly higher percentages and absolute numbers of CD8+ T cells and a lower fraction of CD56+ natural killer (NK) cells than individuals who remained free of GVHD. Thirty-five percent of patients whose PBL were greater than 25% CD8+ in the second posttransplant week developed GVHD, compared with only 3% of patients who had < or = 25% CD8+ cells (odds ratio 37.8; 95% confidence interval [CI] 4.1 to 397). A subgroup of patients at very high risk for GVHD could be identified based on the combined frequency of CD8+ T cells and NK cells in blood. Seventy-five percent of patients with greater than 25% CD8+ cells and < or = 45% CD56+ cells during week 2 post-BMT developed GVHD, compared with only 11% of the remaining patients (odds ratio 24.9; 95% CI, 5.3 to 117.0). None of the 23 patients with both less than 25% CD8+ cells and greater than 45% CD56+ cells in the second posttransplant week developed grades 2–4 GVHD. Our findings indicate that CD8+ T cells play an important role in the pathogenesis of GVHD in humans. Analysis of immune reconstitution early after BMT is useful in predicting the onset of GVHD and can help direct the implementation of treatment strategies before the appearance of clinical manifestations. Such interventions may decrease the morbidity and mortality associated with allogeneic BMT and ultimately improve overall survival.

scholarly journals Differential effects of donor T-cell cytokines on outcome with continuous bortezomib administration after allogeneic bone marrow transplantation

Blood ◽  
2008 ◽  
Vol 112 (4) ◽  
pp. 1522-1529 ◽  
Author(s):  
Kai Sun ◽  
Minghui Li ◽  
Thomas J. Sayers ◽  
Lisbeth A. Welniak ◽  
William J. Murphy
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Bone Marrow Transplantation ◽  
T Cell ◽  
Cd8 T Cells ◽  
Marrow Transplantation ◽  
Allogeneic Bone Marrow Transplantation ◽  
Allogeneic Bone Marrow ◽  
T Cell Subsets ◽  
Allogeneic Bone

Abstract Dissociating graft-versus-tumor (GVT) effect from acute graft-versus-host disease (GVHD) still remains a great challenge in allogeneic bone marrow transplantation (allo-BMT). Bortezomib, a proteasome inhibitor, has shown impressive efficacy as a single agent in patients with hematologic malignancies but can result in toxicity when administered late after allogeneic transplantation in murine models of GVHD. In the current study, the effects of T-cell subsets and their associated cytokines on the efficacy of bortezomib in murine allogeneic BMT were investigated. Increased levels of serum tumor necrosis factor-α (TNFα) and interferon-γ (IFNγ) were observed after allo-BMT and continuous bortezomib administration. Bortezomib-induced GVHD-dependent mortality was preventable by depletion of CD4+ but not CD8+ T cells from the donor graft. The improved survival correlated with markedly reduced serum TNFα but not IFNγ levels. Transfer of Tnf−/− T cells also protected recipients from bortezomib-induced GVHD-dependent toxicity. Importantly, prolonged administration of bortezomib after transplantation of purified CD8+ T cells resulted in enhanced GVT response, which was dependent on donor CD8+ T cell–derived IFNγ. These results indicate that decreased toxicity and increased efficacy of bortezomib in murine allo-BMT can be achieved by removal of CD4+ T cells from the graft or by inhibiting TNFα.

Blocking VIP Signaling during Allogeneic Bone Marrow Transplantation Separates the Graft Versus Leukemia from Graft Versus Host Disease Activity of Donor CD8 T-Cells

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1877-1877
Author(s):  
Jian-Ming Li ◽  
Christopher T Petersen ◽  
Jingxia Li ◽  
Cynthia R. Giver ◽  
Bruce R. Blazar ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Cd8 T Cells ◽  
Ex Vivo ◽  
Allogeneic Bone Marrow Transplantation ◽  
Tumor Burden ◽  
Cytolytic Activity ◽  
Allogeneic Bone ◽  
Donor Cells ◽  
Donor T Cells

Abstract Background: Separating graft versus leukemia (GvL) from graft versus host disease (GvHD) is a critical issue in allogeneic bone marrow transplantation (allo BMT) for malignant hematopoietic cancers. Vasoactive intestinal peptide (VIP) is capable of inducing tolerogenic dendritic cells (DC) from bone marrow progenitors that limit GvHD (Blood 2006 107:3787). We have published that use of donor mice deficient in VIP or pharmacological blockade of VIP-signaling both increased cellular anti-viral activity in murine allo BMT models of CMV infection (JI 2011 187:1057, Blood 2013 121:2347). We hypothesized that blockade of VIP could enhance GvL activity without increasing GvHD in recipients of allo BMT. Methods: We used the B10BR to B6 and B6 to B10BR murine allo BMT models, with luciferase-expressing C1498 acute myeloid leukemia and LBRM acute T-lymphoblastic lymphoma tumor cells, respectively, to study the effect of VIP-signaling on GvL and GvHD. Murine recipients of WT TCD-BM plus splenic allografts (5 x106 TCD-BM plus 0, 0.5, 1.0 and 3.0 x106 splenocytes) were treated with 7 daily s.c. injections of VIPhyb, a VIP antagonist, on d-1 to d+5 (early treatment) or d+6 to d+12 (late treatment), or PBS. Tumor cells were administered by i.v. injection one day before transplant (d-1), and tumor burden was monitored by bioluminescence imaging (BLI). Expression of activation immune cell markers, intracellular cytokines, and ex vivo cytolytic activity against tumor were measured by flow cytometry. TCR-β clono-types were analyzed by TCR-β CDR3 deep sequencing. Results: Recipients of VIP-KO donor cells and VIPhyb-treated recipients of WT donor cells did not have more GvHD than untreated recipients of equivalent numbers of splenocytes from WT donors. VIPhyb-treatment significantly increased survival of transplant tumor recipients in the B10.BR to B6 model with C1498 (2 replicate experiments, n= 10 in VIPhyb early-treatment, p<0.001; n=15 in VIPhyb late-treatment, p=0.005 vs. control, n=14; Figure 1A) and in the B6 to B10.BR model with LBRM (3 replicate experiments in 0.5 x 106 splenocyte dose, n=10, p =0.001 in VIP-KO, n=20, p=0.01 in VIPhyb-treatment, n=40 in control; Figure 1B). All recipients of TCD-BM alone died of tumors within 60 days post-BMT. VIPhyb-treatment, and transplantation of VIP-KO donor cells, led to significant decreases in tumor-burden as measured by BLI. Tumor-free recipients following VIPhyb treatment re-challenged with a 10x dose of LBRM had 100% survival compared with 40% survival among saline-treated recipients (p=0.009). Secondary transplantation of splenocytes from tumor-free VIPhyb-treated recipients resulted in 100% tumor-free survival compared with 30% survival among recipients of naive donor T cells (p=0.001). Splenic T cells, and cDC and pDC from VIPhyb-treated mice expressed lower levels of PD-1, and PD-L1, respectively, compared with saline-treated control (Figure 2). Donor T cells from leukemia-bearing mice treated with VIPhyb expressed higher-levels of ICOS and IFN-γ compared with T cells from saline-treated mice. Both cDC and pDC from VIPhyb-treated mice had increased expression of ICOS-L and MHC-II. Donor T-cells recovered from mice treated with VIPhyb had increased levels of granzyme B and enhanced cytolytic activity against tumor targets but not against non-tumor recipient-type splenocytes or third party splenocytes. Genetic or ex vivo depletion of donor NK cells or CD8+ T-cells abrogated the enhanced GvL activity seen with VIP antagonist-treatment. VIPhyb had no direct anti-proliferative activity against LBRM in vitro using a range of concentrations that exceeded predicted in vivo concentration. VIPhyb-treated transplant recipients had expansion of oligo-clonal T-cell subsets that conferred leukemia protection to secondary recipients and expressed distinct TCR-β sequences compared with T cells from donor or GvHD mice. Conclusions: Blocking VIP signaling enhanced GvL activity without increasing GvHD. Donor CD8+ T-cells and NK cells were indispensable for the enhanced GvL activity. The ability of VIP antagonist treatment to down-regulate PD-1/PD-L1 signaling and enhance adaptive cellular immunity is a novel approach to treat and prevent relapse in allo BMT. Figure 1. VIPhyb-treatment enhanced the GvL activity (5 x 106 TCD BM and 0.5 x 106 splenocytes from WT or VIP-KO donors) Figure 1. VIPhyb-treatment enhanced the GvL activity (5 x 106 TCD BM and 0.5 x 106 splenocytes from WT or VIP-KO donors) Figure 2. VIPhyb-treatment reduced expression of PD-1 on T cells and PD-L1 on DC Figure 2. VIPhyb-treatment reduced expression of PD-1 on T cells and PD-L1 on DC Disclosures No relevant conflicts of interest to declare.

scholarly journals Prediction of graft-versus-host disease by phenotypic analysis of early immune reconstitution after CD6-depleted allogeneic bone marrow transplantation

Blood ◽  
1993 ◽  
Vol 82 (7) ◽  
pp. 2216-2223 ◽  
Author(s):  
RJ Soiffer ◽  
R Gonin ◽  
C Murray ◽  
MJ Robertson ◽  
K Cochran ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Cd8 T Cells ◽  
Odds Ratio ◽  
Allogeneic Bone Marrow Transplantation ◽  
Allogeneic Bone Marrow ◽  
Allogeneic Bone ◽  
Cd8 Cells ◽  
Graft Versus Host ◽  
Marrow Infusion

Abstract Graft-versus-host disease (GVHD) is a major cause of morbidity and mortality following allogeneic bone marrow transplantation (BMT). Because GVHD is frequently refractory to treatment, the early identification of high-risk patients could have significant clinical value. To identify such patients, we examined early immunologic recovery in 136 patients with hematologic malignancies who received anti-T12 (CD6)-purged allogeneic bone marrow over a 9-year period. The majority of patients received marrow from HLA-matched sibling donors after ablation with cyclophosphamide and total body irradiation. No patients received any immune suppressive medications for GVHD prophylaxis. The fraction and absolute numbers of peripheral blood lymphocytes (PBL) expressing the CD3, CD4, CD8, and CD56 surface antigens were determined weekly by immunofluorescence analysis in patients beginning 8 to 14 days (week 2) after marrow infusion. Results in patients who did or did not subsequently develop GVHD post-BMT were compared. Within 2 weeks of marrow infusion, patients who developed grades 2–4 GVHD had significantly higher percentages and absolute numbers of CD8+ T cells and a lower fraction of CD56+ natural killer (NK) cells than individuals who remained free of GVHD. Thirty-five percent of patients whose PBL were greater than 25% CD8+ in the second posttransplant week developed GVHD, compared with only 3% of patients who had < or = 25% CD8+ cells (odds ratio 37.8; 95% confidence interval [CI] 4.1 to 397). A subgroup of patients at very high risk for GVHD could be identified based on the combined frequency of CD8+ T cells and NK cells in blood. Seventy-five percent of patients with greater than 25% CD8+ cells and < or = 45% CD56+ cells during week 2 post-BMT developed GVHD, compared with only 11% of the remaining patients (odds ratio 24.9; 95% CI, 5.3 to 117.0). None of the 23 patients with both less than 25% CD8+ cells and greater than 45% CD56+ cells in the second posttransplant week developed grades 2–4 GVHD. Our findings indicate that CD8+ T cells play an important role in the pathogenesis of GVHD in humans. Analysis of immune reconstitution early after BMT is useful in predicting the onset of GVHD and can help direct the implementation of treatment strategies before the appearance of clinical manifestations. Such interventions may decrease the morbidity and mortality associated with allogeneic BMT and ultimately improve overall survival.

Interleukin-15 enhances immune reconstitution after allogeneic bone marrow transplantation

Blood ◽  
2005 ◽  
Vol 105 (2) ◽  
pp. 865-873 ◽  
Author(s):  
Onder Alpdogan ◽  
Jeffrey M. Eng ◽  
Stephanie J. Muriglan ◽  
Lucy M. Willis ◽  
Vanessa M. Hubbard ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Bone Marrow Transplantation ◽  
T Cell ◽  
Cd8 T Cells ◽  
Marrow Transplantation ◽  
Immune Reconstitution ◽  
Allogeneic Bone Marrow Transplantation ◽  
Allogeneic Bone ◽  
Interleukin 15

AbstractInterleukin-15 (IL-15) is a γ-common cytokine that plays an important role in the development, survival, and proliferation of natural killer (NK), NK T, and CD8+ T-cells. We administered IL-15 to recipients of an allogeneic bone marrow transplantation (allo BMT) to determine its effects on immune reconstitution. Posttransplantation IL-15 administration significantly increased donor-derived CD8+ T (mostly CD122+CD44+CD8+ T-cells), NK, and NK T-cells at day +28 in young and old recipients of allo BMT. This was associated with enhanced T-cell and NK-cell function. IL-15 stimulated homeostatic proliferation of donor CD8+ T-cells in recipients of carboxyfluorescein diacetate succinimidyl ester–labeled donor T-cell infusions. Posttransplantation IL-15 administration also resulted in a decrease in apoptotic CD8+ T-cells, an increase in Bcl-2–expressing CD8+ T-cells, and an increase in the fraction of Ki67+ proliferative NK and CD8+ T-cells in recipients of allo BMT. IL-15 did not exacerbate graft-versus-host disease (GVHD) in recipients of T-cell–depleted BMT but could aggravate GVHD in some cases in recipients of a T-cell–repleted BMT. Finally, we found that IL-15 administration could enhance graft-versus-leukemia activity. In conclusion, IL-15 can be administered safely to recipients of a T-cell–depleted allo BMT to enhance CD8+ T, NK, and NK T-cell reconstitution.

An Essential Role for STAT1 Signaling in Regulation of Donor CD4+ T Cell Dependent Acute Graft Versus Host Disease (GVHD) Following Allogeneic Bone Marrow Transplantation (BMT).

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3551-3551
Author(s):  
Huihui Ma ◽  
Caisheng Lu ◽  
Judith Ziegler ◽  
Suzanne Lentzsch ◽  
Markus Y. Mapara
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Research Funding ◽  
Allogeneic Bone Marrow Transplantation ◽  
Treg Cells ◽  
Allogeneic Bone ◽  
Target Tissue

Abstract Abstract 3551 Poster Board III-488 We have previously demonstrated that activation of STAT1 and STAT3 in target tissue and secondary lymphoid organs belong to the earliest events during induction of GVHD. Using STAT1-gene-deficient (STAT1KO) mice we tested the role of donor STAT1 in fully MHC-mismatched (129Sv[H2b] to BALB/c [H2d]) and MHC-matched minor histocompatibility antigen (mHA)-mismatched strain combinations (129Sv[H2b] to B6[H2b]). GVHD was induced lethal irradiation and transplantation of allogeneic donor bone marrow cells and whole spleen cells. GVHD in the MHC-mismatched model is primarily CD4 dependent. Induction of GVHD was associated with activation of STAT1 and significant expansion of activated STAT1 expressing CD4+ and CD8+ T cells as assessed by analysis of STAT1 Tyr701 phosphorylation using phosphoflow staining. Using STAT1KO whole splenocytes we were able to show that lack of STAT1 significantly inhibited development of GVHD in both major and mHA mismatched recipients with significantly extended median survival times (MST) and lower GVHD morbidity. Protection against GVHD in recipients of STAT1KO splenocytes was associated with significant contraction of CD8+ T cells, but expansion of CD4 T cells on days +3 and +6 post-BMT in the MHC-mismatched setting. Most importantly, we observed a significant expansion of CD4+CD25+ FOXP3+ Treg cells in recipients of STAT1KO splenocytes. Lack of STAT1 in donor splenocytes resulted in a significantly attenuated and skewed systemic inflammatory response on day +6 post-BMT as demonstrated by significantly reduced IFN-g levels 508pg/ml vs 84.pg/ml (p<0.05), but significantly increased IL-4 (p=0.003), IL-5 (p=0.007) and IL-17 (p=0.03) levels. IL-6 levels were also increased with a trend towards statistical significance (p=0.08). In vitro studies demonstrated that STAT1KO CD8+ T cells produced much less IFN-g upon combined engagement of TCR and costimulation, but that this decrease in IFN-g secretion could be rescued if cells were simultaneously cultured under Th1 conditions (ie in the presence of IL-12 and anti-IL4 antibody). In contrast, lack of STAT1 completely inhibited the differentiation of naïve CD4+ T cells to IFN-g -producing cells upon TCR commitment and this capacity was also severely impaired under Th1 conditions. Furthermore, we observed a significantly reduced number of CXCR3−expressing CD4+ T cells in recipients of STAT1 KO splenocytes. In parallel to the afore-mentioned observations, tissue samples from BMT mice on day +3 and day +6 showed significantly less inflammation in liver and gut in recipients of STAT1 KO splenocytes compared to wild type cells. These data indicate that donor STAT1 is important for the induction of acute GVHD and that attenuation of GVHD in the absence of STAT1 involves expansion of Treg cells, perturbation of T cell polarization and subsequent reduced expression of the chemokine receptor CXCR3 on donor T cells leading to impaired target organ infiltration. Disclosures: Lentzsch: Celgene: Consultancy, Research Funding; cephalon: Consultancy, Research Funding. Mapara:Genzyme: Membership on an entity's Board of Directors or advisory committees; Resolvyx: Consultancy, Honoraria, Research Funding; Gentium: Stock Ownership.

scholarly journals Clonally Expanded CD8+ T cells in Allogeneic Bone Marrow Transplantation

2008 ◽  
Vol 59 (6) ◽  
pp. 635-636
Author(s):  
T. M. Kollgaard ◽  
S. Reker ◽  
S. L. Petersen ◽  
T. N. Masmas ◽  
L. L. Vindelov ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Bone Marrow Transplantation ◽  
Cd8 T Cells ◽  
Marrow Transplantation ◽  
Allogeneic Bone Marrow Transplantation ◽  
Allogeneic Bone Marrow ◽  
Allogeneic Bone

scholarly journals Keratinocyte growth factor enhances DNA plasmid tumor vaccine responses after murine allogeneic bone marrow transplantation

Blood ◽  
2009 ◽  
Vol 113 (7) ◽  
pp. 1574-1580 ◽  
Author(s):  
Robert R. Jenq ◽  
Christopher G. King ◽  
Christine Volk ◽  
David Suh ◽  
Odette M. Smith ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Keratinocyte Growth Factor ◽  
Allogeneic Bone Marrow Transplantation ◽  
Allogeneic Bone ◽  
Effector Cells ◽  
Cd8 Cells ◽  
T Cell Reconstitution ◽  
Dna Plasmid

Abstract Keratinocyte growth factor (KGF), which is given exogenously to allogeneic bone marrow transplantation (allo-BMT) recipients, supports thymic epithelial cells and increases thymic output of naive T cells. Here, we demonstrate that this improved T-cell reconstitution leads to enhanced responses to DNA plasmid tumor vaccination. Tumor-bearing mice treated with KGF and DNA vaccination have improved long-term survival and decreased tumor burden after allo-BMT. When assayed before vaccination, KGF-treated allo-BMT recipients have increased numbers of peripheral T cells, including CD8+ T cells with vaccine-recognition potential. In response to vaccination, KGF-treated allo-BMT recipients, compared with control subjects, generate increased numbers of tumor-specific CD8+ cells, as well as increased numbers of CD8+ cells producing interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α). We also found unanticipated benefits to antitumor immunity with the administration of KGF. KGF-treated allo-BMT recipients have an improved ratio of T effector cells to regulatory T cells, a larger fraction of effector cells that display a central memory phenotype, and effector cells that are derived from a broader T-cell–receptor repertoire. In conclusion, our data suggest that KGF can function as a potent vaccine adjuvant after allo-BMT through its effects on posttransplantation T-cell reconstitution.

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