Toll-Like Receptors 2 and 4 Are Involved in the Induction of Graft-Versus-Host-Disease in Mice.

Lipid A ◽

Host Disease ◽

Graft Versus Host ◽

Vitro Data ◽

In Vitro Data

Abstract BACKGROUND: Intestinal Graft-versus-Host disease is a frequent and often lethal complication after allogenic stem cell transplantation. Since NOD2 polymorphisms have been recognized as potential triggers of severe intestinal GvHD in humans, we have developed murine transplantation models to investigate the role of different pattern recognition receptors (PRR) in GvHD and GvL. Here we report our results on the role of TLR2 and TLR4 for the induction of GvHD. METHODS: Severity of GvHD in wildtype (wt) C57B/10 (H-2Db), TLR2−/−, TLR4−/−, and combined TLR2−/−TLR4−/− C57B/10 mice was investigated. Mice received treosulfan 2000 mg/kg from day -3 to -1 and cyclophosphamide 200 mg/kg day -1 prior to injection of 10×10^6 H-2Dd BM cells and 5×10^6 splenocytes (SC). Survival and GvHD score were assessed daily. Engraftment was determined every 2 weeks in pB and at the end of the experiments in bone marrow by flow cytometry. T cell alloreactivity in GvH direction was assessed by MLR using splenocytes as stimulators from PRR-deficient mice or wt as control and CFSE-staining as read-out. The relevance of PRR ligands for the enhancement of GvH alloreactivity was determined by addition of lipid A, lipopetides, or CpG. RESULTS: in vivo data: The transfer of 10×10^6 BMC + 5×10^6 SC induced a severe GvHD in all wt recipients, leading to death of 90% of the animals within 20 days. Recipient mice lacking either TLR2 or TLR4 showed only a slightly and not significantly decreased GvHD lethality. In recipients lacking both PPRs, i.e. TLR2 and TLR4, GvHD was generally milder and the majority (60%) of the animals survived until day 20 (p<0.05). However, the long term survival was not significantly improved. Differences in clinical severity of GvHD were confirmed histologically. In vitro data: Stimulation with cells from TLR2−/− and TLR4−/− mice resulted in a decreased alloreactivity in MLR. A median of 2% of Balb/c CD4+ T cells proliferated in response to C57B/10 stimulators. The addition of the TLR2 and TLR4 ligands lipopeptide, Lipid A and CpG significantly (p<0.05) increased the proliferation of CD4+ T cells in a specific manner more than twofold. CONCLUSION: Our in vivo and in vitro data consistantly show that bacterial components are involved in triggering GvH alloreactivity via different types of PPRs. Binding of bacterial substances to TLR2 and TLR4 leads to activation of the immune system and subsequent induction of GvHD. Our data provide an experimental basis for the development of strategies for modulation of the intestinal gut flora by selective gut decontamination and/or probiotic regimens to prevent GvHD in humans.

Microrna-191 Regulates T-Cell Clonal Expansion during Graft-Versus-Host Disease

Blood ◽

10.1182/blood-2019-130179 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 4433-4433

Author(s):

Chuanfeng Xiong ◽

Wei Huang ◽

Xiaoli Nie ◽

Ying Huang ◽

Yiqun Jiao ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Clonal Expansion ◽

Host Disease ◽

Graft Versus Host ◽

Alloreactive T Cells

Allogeneic hematopoietic cell transplantation is a potentially curative treatment choice for a wide variety of hematological malignancies. However, graft-versus-host disease (GVHD), which is mediated by donor alloreactive T cells, limits the success of this procedure. Previous studies have demonstrated that several microRNAs (miRs) modulate graft-versus-host disease. miR-191 was previously reported to be able to support T cell survival after TCR stimulation. We hypothesize that miR191 regulates T cell response during GVHD. To test this hypothesis, we first studied miR-191 expression in alloreactive T cells. The result demonstrated that miR-191 was up-regulated in donor T cells isolated from murine GVHD recipients, suggesting that miR-191 may play a role in GVHD induction. We further studied the role of miR-191in GVHD using miR-191 deficient T cells (KO). Lethally irradiated (8.5 Gy) BALB/c mice were injected intravenously with 1×107 T cell-depleted bone marrow (TCDBM) cells along with 1×106 purified T cells from wild-type (WT) or KO mice, which are in C57BL/6 background. Interestingly, all recipients in the WT group died within 35 days after transplantation, while only one out of ten animals died in the KO group during an observation period of 56 days. Body weights and clinical scores were also improved in KO T cell recipients when compared with the WT controls. Similar results were also observed in a second GVHD model (C57BL/6→C3H/HeJ). To understand the mechanism by which miR-191 KO T cells have decreased ability to mediate GVHD, we first measured the ability of KO T cells to respond to alloantigens in vitro in a mixed lymphocytes reaction assay. Dramatically decreased alloresponse was observed with KO T cells as compared with WT T cells. Similarly, decreased clonal expansion was observed in KO T cells in vivo upon challenge with alloantigens as measured by bioluminescent imaging (Figure 1A). These results were further supported by data from a co-transfer experiment, in which equal numbers of WT and KO T cells were transplanted into the same GVHD recipient. At day7 after transplantation, KO T cells showed significantly reduced expansion in the spleen and liver compared with WT T cells. Reduced alloresponses mediated by KO T cells may not due to decreased proliferative capability directly as an in vivo carboxyfluorescein succinimidyl ester (CFSE) assay showed a comparable cell division between WT and KO T cells upon challenge with alloantigens. Rather, increased cell death is responsible for decreased alloresponse observed in KO T cells because dramatically increased number of dead cells was observed in KO group compared with WT group upon response to alloantigens in vitro and vivo. To determine the genes that are regulated by miR-191, we did a screening based on the prediction. Humans and mice share more than 100 predicted targets for miR-191. We chose top 20 of these targets for RT-qPCR screening. The result demonstrated that Taf5 was a target gene of miR-191. Expression of TAF5 protein was down-regulated in activated KO T cells when compared with the WT T cells. Finally, we investigated whether miR-191 KO T cells preserve graft-versus-leukemia effects. 1×106 T cells from WT or KO mice were transplanted into lethally irradiated BALB/c mice along with 1×107 TCDBM cells and 1×105 host-type BCL-1 cells. While all recipients that received only TCDBM and tumor cells developed lethal leukemia/lymphoma, none of WT and KO T cells recipients developed tumor. In conclusion, our findings reveal a critical role of miR-191 during GVHD process and demonstrate that miR-191 is a novel therapeutic target for GVHD. Figure 1 Disclosures No relevant conflicts of interest to declare.

Prevention of Transfusion-Associated Graft-Versus-Host Disease by Photochemical Treatment

Blood ◽

10.1182/blood.v93.9.3140 ◽

1999 ◽

Vol 93 (9) ◽

pp. 3140-3147 ◽

Cited By ~ 100

Author(s):

Joshua A. Grass ◽

Tamim Wafa ◽

Aaron Reames ◽

David Wages ◽

Laurence Corash ◽

...

Keyword(s):

T Cells ◽

Gamma Radiation ◽

Clinical Signs ◽

Peripheral Blood Cell ◽

Control Group ◽

Host Disease ◽

Abstract Photochemical treatment (PCT) with the psoralen S-59 and long wavelength ultraviolet light (UVA) inactivates high titers of contaminating viruses, bacteria, and leukocytes in human platelet concentrates. The present study evaluated the efficacy of PCT to prevent transfusion-associated graft-versus-host disease (TA-GVHD) in vivo using a well-characterized parent to F1 murine transfusion model. Recipient mice in four treatment groups were transfused with 108 splenic leukocytes. (1) Control group mice received syngeneic splenic leukocyte transfusions; (2) GVHD group mice received untreated allogeneic splenic leukocytes; (3) gamma radiation group mice received gamma irradiated (2,500 cGy) allogeneic splenic leukocytes; and (4) PCT group mice received allogeneic splenic leukocytes treated with 150 μmol/L S-59 and 2.1 J/cm2UVA. Multiple biological and clinical parameters were used to monitor the development of TA-GVHD in recipient mice over a 10-week posttransfusion observation period: peripheral blood cell levels, spleen size, engraftment by donor T cells, thymic cellularity, clinical signs of TA-GVHD (weight loss, activity, posture, fur texture, skin integrity), and histologic lesions of liver, spleen, bone marrow, and skin. Mice in the control group remained healthy and free of detectable disease. Mice in the GVHD group developed clinical and histological lesions of TA-GVHD, including pancytopenia, marked splenomegaly, wasting, engraftment with donor derived T cells, and thymic hypoplasia. In contrast, mice transfused with splenic leukocytes treated with (2,500 cGy) gamma radiation or 150 μmol/L S-59 and 2.1 J/cm2 UVA remained healthy and did not develop detectable TA-GVHD. Using an in vitro T-cell proliferation assay, greater than 105.1 murine T cells were inactivated by PCT. Therefore, in addition to inactivating high levels of pathogenic viruses and bacteria in PC, these data indicate that PCT is an effective alternative to gamma irradiation for prevention of TA-GVHD.

Characterization of in vitro antimurine thymocyte globulin–induced regulatory T cells that inhibit graft-versus-host disease in vivo

Blood ◽

10.1182/blood-2007-08-106526 ◽

2008 ◽

Vol 111 (3) ◽

pp. 1726-1734 ◽

Cited By ~ 36

Author(s):

Melanie C. Ruzek ◽

James S. Waire ◽

Deborah Hopkins ◽

Gina LaCorcia ◽

Jennifer Sullivan ◽

...

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Antithymocyte Globulin ◽

Mrna Level ◽

Regulatory Cells ◽

Host Disease ◽

Abstract Antithymocyte/antilymphocyte globulins are polyclonal antihuman T-cell antibodies used clinically to treat acute transplant rejection. These reagents deplete T cells, but a rabbit antihuman thymocyte globulin has also been shown to induce regulatory T cells in vitro. To examine whether antithymocyte globulin–induced regulatory cells might be functional in vivo, we generated a corresponding rabbit antimurine thymocyte globulin (mATG) and tested its ability to induce regulatory cells in vitro and whether those cells can inhibit acute graft-versus-host disease (GVHD) in vivo upon adoptive transfer. In vitro, mATG induces a population of CD4+CD25+ T cells that express several cell surface molecules representative of regulatory T cells. These cells do not express Foxp3 at either the protein or mRNA level, but do show suppressive function both in vitro and in vivo when adoptively transferred into a model of GVHD. These results demonstrate that in a murine system, antithymocyte globulin induces cells with suppressive activity that also function in vivo to protect against acute GVHD. Thus, in both murine and human systems, antithymocyte globulins not only deplete T cells, but also appear to generate regulatory cells. The in vitro generation of regulatory cells by anti-thymocyte globulins could provide ad-ditional therapeutic modalities for immune-mediated disease.

Host γd T cells Exacerbate Experimental Acute Graft-Versus-Host Disease through Activation of Host Antigen Presenting Cells.

Blood ◽

10.1182/blood.v104.11.3045.3045 ◽

2004 ◽

Vol 104 (11) ◽

pp. 3045-3045

Author(s):

Yoshinobu Maeda ◽

Pavan Reddy ◽

Chen Liu ◽

D. Keith Bishop ◽

James L.M. Ferrara

Keyword(s):

T Cells ◽

T Cell ◽

Mhc Class Ii ◽

Serum Levels ◽

Host Disease ◽

Graft Versus Host ◽

Full Intensity

Abstract Large numbers of T cells bearing γd T cell receptors are present in graft-versus-host disease (GVHD) target tissues. We investigated the potential role of host γd T cells during acute GVHD in a well-characterized GVHD model following full intensity conditioning (11 Gy TBI). BM and spleen T cells from BALB/c (H2d) donors were transplanted into wild type (wt) B6, aß T cell deficient B6 (aß −/−) or γd T cell deficient B6 (γd −/−) hosts. γd −/− hosts demonstrated significantly better day 35 survival (85%) than wt (40%) or aß−/− hosts (18%) (P<0.05). Reconstitution of γd −/− B6 hosts with B6 type γd T cells 24 hr prior to BMT restored lethal GVHD (50 % day 35 survival). In vivo, γd −/− B6 hosts demonstrated at least a five fold reduction in donor T cell expansion and cytokine production. In vitro, T cells proliferated less when co-cultured with allogeneic γd −/− dendritic cells (DCs) than with wt DCs (40,127 ± 1634 vs. 72,503 ± 1296, P<0.05). BM-derived DCs cultured with γd T cells caused greater proliferation of allogeneic T cells than DCs cultured with aß T cells (15.1 ± 21 x 104 vs. 5.1 ± 1.2 x 104, P<0.05). We next tested the effect of γd T cells on host DCs in vivo using a model system in which only the DCs injected prior to BMT expressed the alloantigen that stimulated the GVHD reaction. MHC Class II −/− B6 mice that had been depleted of γd T cells were given 11 Gy TBI and injected one day prior to BMT with B6 DCs that had been co-cultured either with γd T cells or with medium. On day 0 both groups of recipient mice were injected with BM plus splenic T cells from allogeneic bm12 donors. On day +5, CD4+ donor T cells expanded four times more in recipients of DCs co-cultured with γd T cells than in recipients of control DCs and serum levels of TNF-a were significantly higher (36.7 + 6.8 vs. 21.3 + 3.7 pg/ml, P<0.05). Together these data demonstrate that γd T cells amplify the stimulatory function of host DCs and increase the severity of GVHD, suggesting that a new therapeutic target for the prevention of the major BMT toxicity.

Donor Dual TCR T Cells Preferentially Expand and Mediate Pathologic Alloreactivity in Acute Graft Versus Host Disease

Blood ◽

10.1182/blood.v118.21.1972.1972 ◽

2011 ◽

Vol 118 (21) ◽

pp. 1972-1972

Author(s):

Gerald P. Morris ◽

Geoffrey L Uy ◽

David L Donermeyer ◽

Paul M Allen ◽

John F. DiPersio

Keyword(s):

T Cells ◽

T Cell ◽

Peripheral Blood ◽

Thymic Selection ◽

Cell Repertoire ◽

Host Disease ◽

Abstract Abstract 1972 The nature of the T cell repertoire mediating pathologic in vivo alloreactivity is an important question for understanding the development of acute graft-versus-host disease (aGvHD) following clinical allogeneic transplantation. We have previously demonstrated that the small proportion of T cells that naturally express 2 T cell receptors (TCR) as a consequence of incomplete TCRa allelic exclusion during thymic development contribute disproportionately to the alloreactive T cell repertoire, both in vitro and in vivo in a mouse model of graft versus host disease (GvHD) (J. Immunol., 182:6639, 2009). Here, we extend these findings to human biology, examining dual TCR T cells from healthy volunteer donors (n = 12) and patients who have undergone allogeneic hematopoietic stem cell transplantation (HSCT) (n = 19). Peripheral blood was collected at day 30 post-HSCT or at the time of presentation with symptomatic acute GvHD. Dual TCR T cells were measured in peripheral blood by pair-wise staining with 3 commercially-available and 2 novel TCRa mAbs. Dual TCR T cells were consistently and significantly expanded in patients with symptomatic aGvHD, representing 5.3±3.8 % of peripheral T cells, compared to 1.7±0.8 % of T cells in healthy controls (p < 0.005) (Figure 1). There was no correlation between dual TCR T cell frequency and GvHD severity. Furthermore, sequential analysis of peripheral blood in 2 patients demonstrated expansion of dual TCR T cells concurrent with the development of aGvHD (Figure 2). Dual TCR T cells from patients with symptomatic aGvHD demonstrated increased expression of CD69 as compared to T cells expressing a single TCR, indicative of preferential activation of dual TCR T cells during aGvHD. Similarly, dual TCR T cells isolated from patients with symptomatic aGvHD demonstrate increased production of IFN-g ex vivo, indicative of the ability to mediate pathogenic alloreactive responses. Dual TCR T cell clones isolated from healthy donors and patients post-HSCT by single cell FACS sorting demonstrate alloreactive responses against a range of allogeneic cell lines in vitro. We propose that the increased alloreactivity of dual TCR T cells results from the less stringent thymic selection for secondary TCR, and thus provides a link between thymic selection, the TCR repertoire, and alloreactivity. These findings may lead to simple ways of phenotypically identifying specific T cells predisposed to inducing aGvHD for subsequent examination of T cell repertoires and functional studies. Furthermore, these data suggest that dual TCR T cells represent a potential predictive biomarker for aGvHD and a potential target for selective T cell depletion in HSCT. Disclosures: No relevant conflicts of interest to declare.

G-CSF as immune regulator in T cells expressing the G-CSF receptor: implications for transplantation and autoimmune diseases

Blood ◽

10.1182/blood-2002-04-1200 ◽

2003 ◽

Vol 102 (2) ◽

pp. 734-739 ◽

Cited By ~ 130

Author(s):

Anke Franzke ◽

Wenji Piao ◽

Jörg Lauber ◽

Patricia Gatzlaff ◽

Christian Könecke ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

Autoimmune Diseases ◽

Bone Marrow Failure ◽

Host Disease ◽

Graft Versus Host ◽

Acute Graft

Abstract Results from experimental models, in vitro studies, and clinical data indicate that granulocyte colony-stimulating factor (G-CSF) stimulation alters T-cell function and induces Th2 immune responses. The immune modulatory effect of G-CSF on T cells results in an unexpected low incidence of acute graft-versus-host disease in peripheral stem cell transplantation. However, the underlying mechanism for the reduced reactivity and/or alloreactivity of T cells upon G-CSF treatment is still unknown. In contrast to the general belief that G-CSF acts exclusively on T cells via monocytes and dendritic cells, our results clearly show the expression of the G-CSF receptor in class I– and II– restricted T cells at the single-cell level both in vivo and in vitro. Kinetic studies demonstrate the induction and functional activity of the G-CSF receptor in T cells upon G-CSF exposure. Expression profiling of T cells from G-CSF–treated stem cell donors allowed identification of several immune modulatory genes, which are regulated upon G-CSF administration in vivo (eg, LFA1-α, ISGF3-γ) and that are likely responsible for the reduced reactivity and/or alloreactivity. Most importantly, the induction of GATA-3, the master transcription factor for a Th2 immune response, could be demonstrated in T cells upon G-CSF treatment in vivo accompanied by an increase of spontaneous interleukin-4 secretion. Hence, G-CSF is a strong immune regulator of T cells and a promising therapeutic tool in acute graft-versus-host disease as well as in conditions associated with Th1/Th2 imbalance, such as bone marrow failure syndromes and autoimmune diseases.

Inhibition of Graft-Versus-Host Disease (GVHD) by Histone Deacetylase Inhibitor (HDAC) SAHA Leads to Downregulation of STAT1 Activation.

Blood ◽

10.1182/blood.v106.11.1311.1311 ◽

2005 ◽

Vol 106 (11) ◽

pp. 1311-1311

Author(s):

Corinna Leng ◽

Cuiling Li ◽

Judy Ziegler ◽

Anna Lokshin ◽

Suzanne Lentzsch ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Histone Deacetylase ◽

Host Disease ◽

Graft Versus Host ◽

Tnf Α ◽

Ifn Γ

Abstract Histone deacetylase (HDAC) inhibitors have been shown to reduce development of graft versus host disease [GVHD] following allogeneic bone marrow transplantation [BMT]. Administration of the HDAC inhibitor suberonylanilide hydroxamic acid [SAHA] resulted in a significantly reduced GVHD-dependent mortality following fully MHC-mismatched allogeneic BMT. Median Survival Time (MST) for vehicle and SAHA-treated mice were 7.5 days and 38 days respectively. However, SAHA treatment did not affect T cell activation nor T cell expansion in vitro and in vivo as determined by MLR assays, phenotypic analysis of donor T cells with regard to expression of the CD25 activation antigen and calculation of donor CD4+ and CD8+ T cell numbers on days +3 and +6 post-BMT. Thus, SAHA treatment was not able to inhibit the strong upregulation of CD25 antigen on CD8+ T cells observed during induction of GVHD on days +3 and +6 post-BMT. We therefore focused on the effects of SAHA treatment on efferent immune effects including cytokine secretion and intracellular signaling events in vitro and in vivo following GVHD induction. SAHA treatment broadly inhibited lipopolysaccharide [LPS] and allo-antigen-induced cytokine/chemokine secretion in vitro like MIP-1-α, IP-10, IFN-γ, TNF-α and IL-6 and led also to a significant decrease in IFN-γ and TNF-α levels in vivo following induction of GVHD. Concomitantly, SAHA treatment inhibited phosphorylation of STAT1 and STAT3 in response to LPS and allo-activation in vitro. Furthermore, analysis of liver tissue and spleens from SAHA-treated animals with GVHD showed a significant decrease in phosphorylated STAT1. In contrast SAHA treatment had only moderate effects on p38 or ERK1,2 Mitogen-activated Protein Kinase (MAPK) pathway underscoring the relevance of the inhibition of the STAT1 pathway. In conclusion, GVHD is associated with a strong induction of phosphorylation of STAT1 in the liver and spleen and SAHA-dependent reduction of GVHD is associated with systemic and local inhibition of pSTAT1 and modulation of the inflammatory cytokine milieu during the efferent immune response.

Superagonistic CD28 stimulation of allogeneic T cells protects from acute graft-versus-host disease

Blood ◽

10.1182/blood-2009-04-218248 ◽

2009 ◽

Vol 114 (20) ◽

pp. 4575-4582 ◽

Cited By ~ 28

Author(s):

Niklas Beyersdorf ◽

Xin Ding ◽

Thomas Hünig ◽

Thomas Kerkau

Keyword(s):

T Cells ◽

Hematologic Malignancies ◽

Therapeutic Window ◽

Host Disease ◽

Graft Versus Host ◽

Acute Graft ◽

Stimulation Of

Abstract Acute graft-versus-host disease (aGVHD) often precludes successful immunotherapy of hematologic malignancies with allogeneic T cells. Therefore, we investigated the effect of immunomodulatory superagonistic anti-CD28 monoclonal antibodies (CD28-SA) on the capacity of allogeneic T cells to mediate both aGVHD and the protective graft-versus-tumor (GVT) response. In vivo pretreatment of donor C57BL/6 mice or short-term in vitro culture of donor lymph node cells with a CD28-SA efficiently protected BALB/c recipient mice from aGVHD. This protection strongly relied on the presence of CD28-SA–activated CD4+ CD25+ Foxp3+ regulatory T cells in the donor T-cell inoculum. With respect to the GVT response, CD28-SA–prestimulated T cells were still as potent in clearing lymphoma cells as were T cells without CD28-SA preactivation. Taken together, our data suggest that CD28-SA stimulation of bulk leukocyte cultures in vitro markedly increases the therapeutic window for adoptive immunotherapy with allogeneic T cells in vivo.

Role of MMP-13 in Graft-Versus-Host Disease

Blood ◽

10.1182/blood-2019-127703 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 1928-1928

Author(s):

Hui-Hui Ma ◽

Jing Fu ◽

Suzanne Lentzsch ◽

Markus Y Mapara

Keyword(s):

Bone Marrow ◽

T Cells ◽

Dendritic Cells ◽

Research Funding ◽

Host Disease ◽

Graft Versus Host ◽

Donor T Cells

Matrix metalloproteinases (MMPs) have been initially recognized for their role in degradation of extracellular matrix (ECM) and collagen remodeling. However, MMPs have been shown to play a crucial role in inflammation, tumor cell invasion, adaptive and innate immunity. Acute and chronic Graft versus Host Disease (GVHD) are characterized by distinctive histopathological features involving tissue infiltration with donor cells, tissue damage and remodeling. We therefore hypothesized that GVHD-associated organ damage may involve MMPs. We have now identified a novel immunomodulatory function for MMP-13 (alternatively called collagenase-3)and have uncovered a previously unknown role of MMP-13 in regulating GVHD.To address the function of MMP-13 in GVHD we first assesed the effect of MMP-13 on alloresponses in vitro. Using fully Major Histocompatibility Complex (MHC)-mismatched standard mixed lymphocyte reaction we demonstated that antigen presentig cells (APC) from B6.MMP-13-/-(H2b) mice led to signifcantly enhanced antigen-driven activation and proliferation of Carboxyfluorescein succinimidyl ester (CFSE)-labeled Balb/c responder splenocytes. Thus, MMP-13 deficiency in either splenocytes or bone marrow-derived dendritic cells used as stimulators resulted in enhanced proliferation, activation and IFN-gproduction in the allo-reactive lymphocyte responders. Similarly, exogenous MMP13 reduced proliferation of responder T cells as determined tested by CFSEdilution (CFSEloof CD4+T cells from 62.3% decreased to 40.6%, CFSEloof CD8+T cells from 74.1% down to 47.9%). We next assessed the impact of MMP-13 in vivousing fully MHC-mismatched rodent acute GVHD models. To study the role of host-derived MMP-13 we induced GVHD in B6.MMP-13-/-or B6.WT recipient mice following lethal TBI (1075 rad) using splenic T cells from Balb/cdonors. We observed signifcantly accelerated GVHD-related mortality (Median Survival Time 7 vs. 47 days post-transplant, p<0.05) in MMP-13-deficient recipients. Most importantly, donor T cells expanded more vigorously in the secondary lymphoid organs (Spleen and mesenteric lymphnoodes) of MMP13-/-compared to wildtype recipient mice (e.g. spleen: absolute donor CD4+Tcells 1.5x104± 7.3 x 103 (WT) vs. 5.83 x104±1.65 x104[MMP-13-/-] and CD8+5.5 x104± 3.8 x104(WT) vs 3.4 x105±1.4 x105[MMP-13-/-], p<0.01). Enhanced donor lymphocyte expansion was further confirmed by bioluminescence imaging. To further delineate the underlying mechanisms, we analyzed the effects of MMP-13deficiency and exogenous MMP-13 on maturation of mouse bone marrow derived-dendritic cells (BMDC) and macrophages in vitro. We noted decreased expression of inhibitory molecules PD-L1 and PD-1H on GM-CSF/LPS cultured BMDC. Similarly, bone marrow-derived MMP-13-/-macrophages also showed reduced PD-L1 and PD-1H expression upon LPS stimulation when compared to their WT counterparts. In summary we posit that recipient myeloid cell-derived MMP-13 mitigates GVHD and limits donor T cell expansion. Further studies are warranted to determine how MMP-13 suppresses expansion of donor T cells and impacts Graft-versus-Leukemia responses. Disclosures Lentzsch: Caelum Biosciences: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Bayer: Consultancy; Janssen: Consultancy; Takeda: Consultancy; Abbvie: Consultancy; Clinical Care Options: Speakers Bureau; Sanofi: Consultancy, Research Funding; Multiple Myeloma Research Foundation: Honoraria; International Myeloma Foundation: Honoraria; Karyopharm: Research Funding; Columbia University: Patents & Royalties: 11-1F4mAb as anti-amyloid strategy; Proclara: Consultancy; BMS: Consultancy.

Protection from graft-versus-host disease by HIV-1 envelope protein gp120-mediated activation of human CD4+CD25+ regulatory T cells

Blood ◽

10.1182/blood-2009-02-206730 ◽

2009 ◽

Vol 114 (6) ◽

pp. 1263-1269 ◽

Cited By ~ 55

Author(s):

Christian Becker ◽

Christian Taube ◽

Tobias Bopp ◽

Christoph Becker ◽

Kai Michel ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Regulatory T Cells ◽

Immune Responses ◽

Adenosine Monophosphate ◽

Host Disease ◽

AbstractNaturally occurring CD4+CD25+ regulatory T cells (Tregs) represent a unique T-cell lineage that is endowed with the ability to actively suppress immune responses. Therefore, approaches to modulate Treg function in vivo could provide ways to enhance or reduce immune responses and lead to novel therapies. Here we show that the CD4 binding human immunodeficiency virus-1 envelope glycoprotein gp120 is a useful and potent tool for functional activation of human Tregs in vitro and in vivo. Gp120 activates human Tregs by binding and signaling through CD4. Upon stimulation with gp120, human Tregs accumulate cyclic adenosine monophosphate (cAMP) in their cytosol. Inhibition of endogeneous cAMP synthesis prevents gp120-mediated Treg activation. Employing a xenogeneic graft versus host disease model that has been shown to be applicable for the functional analysis of human Tregs in vivo, we further show that a single dose of gp120 is sufficient to prevent lethal graft versus host disease and that the tolerizing effect of gp120 is strictly dependent on the presence of human Tregs and their up-regulation of cAMP upon gp120-mediated activation. Our findings demonstrate that stimulation via the CD4 receptor represents a T-cell receptor–independent Treg activating pathway with potential to induce immunologic tolerance in vivo.