http://hdl.handle.net/2268/103 Search this channel search http://orbi.ulg.ac.be/simple-search http://hdl.handle.net/2268/147839 Title: A novel mutation in the CUB sequence of matriptase-2 (TMPRSS6) is implicated in iron-resistant iron deficiency anaemia (IRIDA). <br/> <br/>Author, co-author: JASPERS, Aurélie; CAERS, Jo; LE GAC, Gerald; FEREC, Claude; BEGUIN, Yves; FILLET, Georges Fri, 03 May 2013 06:45:09 GMT http://hdl.handle.net/2268/147264 Title: Strongyloidiasis and Infective Dermatitis Alter Human T Lymphotropic Virus-1 Clonality in vivo. <br/> <br/>Author, co-author: Gillet, Nicolas; Cook, Lucy; Laydon, Daniel J.; Hlela, Carol; Verdonck, Kristien; Alvarez, Carolina; Gotuzzo, Eduardo; Clark, Daniel; Farre, Lourdes; Bittencourt, Achilea; Asquith, Becca; Taylor, Graham P.; Bangham, Charles R. M. <br/> <br/>Abstract: Human T-lymphotropic Virus-1 (HTLV-1) is a retrovirus that persists lifelong by driving clonal proliferation of infected T-cells. HTLV-1 causes a neuroinflammatory disease and adult T-cell leukemia/lymphoma. Strongyloidiasis, a gastrointestinal infection by the helminth Strongyloides stercoralis, and Infective Dermatitis associated with HTLV-1 (IDH), appear to be risk factors for the development of HTLV-1 related diseases. We used high-throughput sequencing to map and quantify the insertion sites of the provirus in order to monitor the clonality of the HTLV-1-infected T-cell population (i.e. the number of distinct clones and abundance of each clone). A newly developed biodiversity estimator called "DivE" was used to estimate the total number of clones in the blood. We found that the major determinant of proviral load in all subjects without leukemia/lymphoma was the total number of HTLV-1-infected clones. Nevertheless, the significantly higher proviral load in patients with strongyloidiasis or IDH was due to an increase in the mean clone abundance, not to an increase in the number of infected clones. These patients appear to be less capable of restricting clone abundance than those with HTLV-1 alone. In patients co-infected with Strongyloides there was an increased degree of oligoclonal expansion and a higher rate of turnover (i.e. appearance and disappearance) of HTLV-1-infected clones. In Strongyloides co-infected patients and those with IDH, proliferation of the most abundant HTLV-1(+) T-cell clones is independent of the genomic environment of the provirus, in sharp contrast to patients with HTLV-1 infection alone. This implies that new selection forces are driving oligoclonal proliferation in Strongyloides co-infection and IDH. We conclude that strongyloidiasis and IDH increase the risk of development of HTLV-1-associated diseases by increasing the rate of infection of new clones and the abundance of existing HTLV-1(+) clones. Tue, 23 Apr 2013 14:59:29 GMT http://hdl.handle.net/2268/147262 Title: Genome-wide Determinants of Proviral Targeting, Clonal Abundance and Expression in Natural HTLV-1 Infection. <br/> <br/>Author, co-author: Melamed, Anat; Laydon, Daniel J.; Gillet, Nicolas; Tanaka, Yuetsu; Taylor, Graham P.; Bangham, Charles R. M. <br/> <br/>Abstract: The regulation of proviral latency is a central problem in retrovirology. We postulate that the genomic integration site of human T lymphotropic virus type 1 (HTLV-1) determines the pattern of expression of the provirus, which in turn determines the abundance and pathogenic potential of infected T cell clones in vivo. We recently developed a high-throughput method for the genome-wide amplification, identification and quantification of proviral integration sites. Here, we used this protocol to test two hypotheses. First, that binding sites for transcription factors and chromatin remodelling factors in the genome flanking the proviral integration site of HTLV-1 are associated with integration targeting, spontaneous proviral expression, and in vivo clonal abundance. Second, that the transcriptional orientation of the HTLV-1 provirus relative to that of the nearest host gene determines spontaneous proviral expression and in vivo clonal abundance. Integration targeting was strongly associated with the presence of a binding site for specific host transcription factors, especially STAT1 and p53. The presence of the chromatin remodelling factors BRG1 and INI1 and certain host transcription factors either upstream or downstream of the provirus was associated respectively with silencing or spontaneous expression of the provirus. Cells expressing HTLV-1 Tax protein were significantly more frequent in clones of low abundance in vivo. We conclude that transcriptional interference and chromatin remodelling are critical determinants of proviral latency in natural HTLV-1 infection. Tue, 23 Apr 2013 14:57:29 GMT http://hdl.handle.net/2268/146349 Title: Diffuse large B-cell lymphomas of the waldeyer's ring frequently have a germinal center-like phenotype: a clinico-pathological study of 209 patients from the groupe d'étude des lymphomes de l'adulte (GELA). <br/> <br/>Author, co-author: de Leval, Laurence; Bonnet, Christophe; Copie-Bergman, C.; Seidel, Laurence; Baia, M; Brière, J.; Molina, T.; Fabiani, B.; Falini, B.; Gisselbrecht, C.; Thilly, H.; Albert, Adelin; Fillet, Georges; Gaulard, P. Mon, 08 Apr 2013 03:00:30 GMT http://hdl.handle.net/2268/146348 Title: In vitro ototoxicity of aminoglycosides and platin derivatives. A semi-automatic assay for sensory hair cell damage in explanted rat organ of corti. <br/> <br/>Author, co-author: Malgrange, B.; LEFEBVRE, Philippe; van de Water, T.R.; Bonnet, Christophe; Monville, F.; Rigo, J.-M.; Staecker, H.; Moonen, Gustave <br/> <br/>Abstract: The ototoxic damage that drugs such as neomycin, kanamycin, colistin, cisplatin, transplatin and carboplatin cause on outer and inner hair cells in postnatal day 3 rat cochlear explants was investigated. Phalloidin-fluorescein conjugate-stained stereocilia bundles of sensory hair cells were quantified by video image analysis as a measurement of ototoxic effect. The video image quantification system established dose-response curves for ototoxic drugs (e.g. calculation of an IC50) and allowed comparisons between several ototoxins from the same family. This methodology provided the means to assess the efficacy of otoprotectant agents in preventing ototoxicity. Poly-l-aspartate (10-5M) and poly-l-glutamate (10-5M) protected auditory hair cells from neomycin (10-3M) toxicity while reduced glutathione (10-3M) provided protection against cisplatin (10-4M)-induced hair cell damage. Mon, 08 Apr 2013 03:00:08 GMT http://hdl.handle.net/2268/146260 Title: Diffuse large B-cell lymphoma of Waldeyer's ring has distinc clinicopathologic features: a GELA study. <br/> <br/>Author, co-author: de Leval, Laurence; Bonnet, Christophe; Copie-Bergman, C.; Seidel, Laurence; Baia, M.; Brière, J.; Molina, T.J.; Fabiani, B.; Petrella, T.; Bosq, J.; Gisselbrecht, C.; Siebert, R.; Tilly, H.; Haioun, C.; Fillet, Georges; Gaulard, P. <br/> <br/>Abstract: Background Diffuse large B-cell lymphomas (DLBCLs) arising in specific extranodal sites have peculiar clinicopathologic features. Patients and methods We analyzed a cohort of 187 primary Waldeyer's ring (WR) DLBCLs retrieved from GELA protocols using anthracyclin-based polychemotherapy. Results Most patients (92%) had stage I–II disease. A germinal center B-cell-like (GCB) immunophenotype was observed in 61%, and BCL2 expression in 55%, of WR DLBCLs. BCL2, BCL6, IRF4 and MYC breakpoints were observed in, respectively, 3 of 42 (7%), 9 of 36 (25%), 2 of 26 (8%) and 4 of 40 (10%) contributive cases. A variable follicular pattern was evidenced in 30 of 68 (44%) large biopsy specimens. The 5-year progression-free survival (PFS) and the overall survival (OS) of 153 WR DLBCL patients with survival information were 69.5% and 77.8%, respectively. The GCB immunophenotype correlated with a better OS (P = 0.0015), while BCL2 expression predicted a worse OS (P = 0.037), an effect overcome by the GCB/non-GCB classification. Compared with matched nodal DLBCLs, WR DLBCLs with no age-adjusted international prognostic index factor disclosed a better 5-year PFS rate (77.5% versus 70.7%; P = 0.03). Conclusions WR DLBCLs display distinct clinicopathologic features compared with conventional DLBCLs, with usual localized-stage disease, common follicular features and a high frequency of GCB immunophenotype contrasting with a low rate of BCL2 rearrangements. In addition, they seem to be associated with a better outcome than their nodal counterpart. Sun, 07 Apr 2013 03:00:34 GMT http://hdl.handle.net/2268/146145 Title: Association between Epstein-Barr virus and Hodgkin's lymphoma in Belgium: A pathological and virological study <br/> <br/>Author, co-author: Trimeche, M.; Bonnet, Christophe; Korbi, S.; Boniver, Jacques; de Leval, Laurence <br/> <br/>Abstract: The association between Epstein-Barr virus (EBV) and classical Hodgkin's lymphoma (cHL) varies according to the geographic location. In this work we sought to characterize EBV involvement in a series of 111 cHL cases diagnosed in Belgium. The overall prevalence of EBV infection detected by in situ hybridization in Reed-Sternberg cells was 33%. EBV positivity correlated with older age at diagnosis (454 years; p = 0.01), mixed cellularity subtype (p = 0.000001), male gender (p = 0.004) and tended to be associated with higher clinical stage (III/IV; p = 0.02). The molecular features of the virus in EBV-positive cHL were studied by comparison with a series of reactive tonsils. A 30-bp deletion within the LMP-1 gene was in 15/28 (53.6%) EBV-positive cHL cases, and in 41.7% of reactive tonsil samples. This variant did not correlate with any clinical or pathological feature. The EBV strain was type A in all cHL and reactive samples. Fri, 05 Apr 2013 03:02:56 GMT http://hdl.handle.net/2268/146144 Title: Simultaneous diagnosis of CLL and CML in a single patient with evidence for two different cell clones <br/> <br/>Author, co-author: Bonnet, Christophe; MENTEN, Catherine; LAMBERT, Frédéric; Gothot, André; Baron, Frédéric; CAERS, Jo; HERENS, Christian; Beguin, Yves Fri, 05 Apr 2013 03:02:46 GMT http://hdl.handle.net/2268/144745 Title: Production locale des antisérums de groupe sanguin ABO <br/> <br/>Author, co-author: Bamoleke Sefu, Anaclet; Tshiband-a-Tshish, Alphonse; Munlemvo Mavanga, Nana; Kiampa Malime, Philomène; Kazadi kabongo, Rigobert; Yuma Ramazani, Sylvain Wed, 13 Mar 2013 21:24:42 GMT http://hdl.handle.net/2268/144727 Title: Rapamycin prevents experimental sclerodermatous chronic graft-versus-host disease in mice <br/> <br/>Author, co-author: Belle, Ludovic; Binsfeld, Marilène; DUBOIS, Sophie; Hannon, Muriel; CAERS, Jo; Briquet, Alexandra; MENTEN, Catherine; Beguin, Yves; Humblet-Baron, Stéphanie; Baron, Frédéric <br/> <br/>Abstract: Background: The most widely used mice model of chronic graft-versus-host disease (cGvHD) is an MHC-matched bone marrow transplantation model of sclerodermatous cGvHD. A limitation of that model is that mortality is relatively low, making difficult to study the impact of potentially therapeutic compounds. Aims: To develop a more severe model of cGVHD and to assess the impact of Rapamycin administration in that model. Results: Lethally irradiated Balb/C mice were injected with 10x106 bone marrow cells and 70x106 splenocytes from B10.D2 donor mice. Twenty-one days later, all mice developed cGvHD. For the severe model, donor B10.D2 mice were injected with 0.5x106 splenocytes from Balb/C twenty-one days before transplantation. All mice from the severe model (n=8) died a median of 32 days while 3 of 7 mice in the classical model survived beyond day 52. Mean survival was decreased in the severe model compared to the classical model (32 days versus 37 days; p=0.0185). Recipient mice in the severe group experienced higher weight loss, hair loss and skin fi brosis. Numbers of T lymphocytes (231.9 ± 151.4 versus 951 ± 532.8; p=0.0032) and CD4+ T cells (63.25 ± 41.93 versus 135.0 ± 14.39; p=0.0018) per microliter of blood at day 21 were lower in the severe group than in the classical model. Moreover, number of regulatory T cells (Tregs) was decreased in the severe model (1.250 ± 0.8864 versus 8.000 ± 6.753; p=0.0151). We then investigated whether rapamycin administration could prevent GVHD in the severe model. All (n=8) mice treated with PBS (placebo) died a median of 32 days after transplantation, while 6 of 8 mice given 1 mg/kg/day i.p. rapamycin survived beyond day 52 (p=0.0012). Number of Tregs/μl was higher at day 21 in rapamycin-treated mice than in mice given PBS (2.000±1.195 versus 1.250±0.8864; p=0.0796). Moreover, number of naïve CD4+T (10.00±4.192 versus 30.25±5.185; p= 0.0089) and effector memory T cells (EMT) (30.67±3.180 versus 67.33±7.881; p= 0.0125) were higher in rapamycin mice. Finally, proliferation of EMT (assessed by fl ow cytometry using Ki-67) was higher in PBS than in rapamycin mice (45.28%±4.084 versus 31.90%± 2.003; p=0.0474). Conclusion: We have developed a mice model of severe cGVHD. Interestingly, rapamycin prevented death from cGVHD in that model, perhaps through in vivo expansion of Treg. Wed, 13 Mar 2013 15:50:21 GMT http://hdl.handle.net/2268/144726 Title: Impact of chronic graft-versus-host disease after reduced-intensity conditioning allogeneic stem cell transplantation for acute myeloid leukaemia: A report from the Acute Leukaemia Working Party of the European Group for Blood and Marrow Transplantation <br/> <br/>Author, co-author: Baron, Frédéric; Labopin, M.; Niederwieser, D.; Vigouroux, S.; Cornelissen, J.; Malm, C.; Vindelov, L.; Blaise, D.; Janssen, J.; Petersen, E.; Socie, G.; Nagler, A.; Rocha, V.; Mohty, M. <br/> <br/>Abstract: We investigated the impact of occurrence of GVHD on transplantation outcomes in a large cohort of AML pts given allogeneic PBSC after RIC conditioning. Data from 1859 AML pts in fi rst (n=1439) or second (n=420) CR transplanted between 2000 and 2009 following a RIC regimen at EBMT affi liated centres were analyzed. Pts were given PBSC from HLA-identical sibling (MRD, n=1208), or from HLA-matched unrelated donors (MUD, n=651). ATG was given in 269 (22%) MRD and in 267 (41%) MUD recipients, respectively, while 151 (13%) MRD and 165 (25%) MUD recipients received in-vivo T cell depletion with alemtuzumab. The impact of chronic GVHD (cGVHD) on outcomes was assessed using time-dependent multivariate Cox models and in a landmark analysis at 18 months after transplant. The 3-y cumulative incidence of cGVHD was 47%. Fifty-three percent of patients with cGVHD had extensive cGVHD, while the remaining 47% had limited cGVHD. In multivariate analyses, occurrence of grade II-IV aGVHD was associated with a lower risk of relapse (HR=0.8; P=0.04), a higher risk of chronic (HR=2.2; P<0.001) and extensive chronic GVHD (HR=2.8; P<0.001), a higher risk of NRM (HR=2.4 P<0.001), a worsened LFS (HR=1.3; P=0.01), and a worsened OS (HR=1.5; P<0.001). In multivariate time-dependent analyses, occurrence of limited cGVHD was associated with a lower risk of relapse (HR=0.7; P=0.05), comparable NRM (HR=1.4; P=0.16), comparable LFS (HR=0.9; P=0.29) and better OS (HR=0.5; P<0.001), while occurrence of extensive cGVHD was associated with a lower risk of relapse (HR=0.6; P=0.01), higher NRM (HR=3.2; P<0.001), a trend for worsened LFS (HR=1.3; P=0.06) and comparable OS (HR=0.9; P=0.34). In a landmark analysis in patients who were leukemia-free at 18 months after transplantation (n=776), 2-year relapse, NRM, LFS and OS were 16±2%, 2.5±1%, 82±2%, and 89±2%, respectively, in patients without cGVHD before the landmark time-point, versus 9±1% (P=0.001), 8±1% (P<0.001), 83±2% (P=0.65), and 86±2% (P=0.38), respectively, in patients with cGVHD before the landmark time-point. In conclusion, in this cohort of AML patients transplanted in remission, occurrence of cGVHD was associated with a lower risk of relapse that translated to better OS in patients with limited cGVHD but not in those with extensive cGVHD who experienced higher long term NRM. These results highlight the role of the GVT effect in RIC allo-SCT, but also the need for improving the prevention of severe cGVHD in pts receiving RIC allo-SCT. Wed, 13 Mar 2013 15:49:51 GMT http://hdl.handle.net/2268/144725 Title: Impact of alemtuzumab versus anti-thymocyte globulin after unrelated allogeneic stem cell transplantation with reduced-intensity conditioning as treatment for AML in CR1: a survey from the Acute Leukaemia Working Party of the EBMT <br/> <br/>Author, co-author: Baron, Frédéric; Labopin, M.; Mufti, G.; Arnold, R.; Craddock, C.; Bilger, K.; Kroger, N.; Nagler, A.; Mohty, M. <br/> <br/>Abstract: In vivo T cell depletion of the graft with anti-thymocyte globulin (ATG) or with alemtuzumab has been frequently used in the setting of RIC allo-SCT from unrelated donors. This survey compared allo-SCT outcomes between 364 AML patients in first CR given unrelated PBSC after chemotherapy-based RIC and given either ATG (n=213) or alemtuzumab (n=151) in the conditioning regimen. Alemtuzumab patients were more frequently given grafts from HLA-mismatched donors (30% versus 16% having at least 1/10 HLA-mismatch with their donor, P=0.005), and were conditioned more often with melphalan-based RIC (62%), while ATG recipients were more frequently conditioned with busulfan-based RIC (84%). Median time to neutrophil engraftment (>500 ANC) was 16 days in ATG recipients, versus 12 days in alemtuzumab recipients (P<0.001). The incidence of grade II-IV acute GVHD was 28% in ATG recipients (9 patients with grade IV) and 24% (NS) in alemtuzumab recipients (2 patients with grade IV). Two-year incidences of chronic GVHD, relapse and NRM were 45%, 23% and 14%, respectively, in ATG recipients, and 47% (NS), 25% (NS) and 25% (P=0.008), respectively, in alemtuzumab recipients. Two-year OS and LFS were 69% and 63%, respectively, in ATG recipients, versus 55% (P=0.003) and 51% (P=0.02), respectively, in alemtuzumab recipients. Death from infection occurred in 7% of ATG recipients, versus 12% of alemtuzumab recipients. When the analysis was restricted to the 210 patients given grafts from 10/10 HLA-matched unrelated donors, the use of alemtuzumab (n=64) remained signifi cantly associated with higher NRM (22% vs 9%, P=0.007), lower LFS (58% vs 69%, P=0.07), and lower OS (62% vs 74%, P=0.04). In multivariate analyses (performed in patients given grafts from 10/10 HLA-matched donors), in comparison to the use of ATG, the use of alemtuzumab was associated with higher NRM (HR=2.5, P=0.025), a statistically non-signifi cant but higher relapse rate (HR=1.7, P=0.18), and signifi cantly worse LFS (HR=0.5, P=0.013) and OS (HR=0.4, P=0.002). In summary, this homogeneous cohort of AML patients transplanted in fi rst CR and given PBSC grafts from unrelated donors, the use of alemtuzumab in comparison with ATG was associated with worse LFS and OS. Wed, 13 Mar 2013 15:49:25 GMT http://hdl.handle.net/2268/144724 Title: Co-transplantation of mesenchymal stem cells might mitigate acute GvHD without abrogating graftversus- tumour alloreactivity after allogeneic transplantation with non-myeloablative conditioning <br/> <br/>Author, co-author: Baron, Frédéric; WILLEMS, Evelyne; LECHANTEUR, Chantal; BAUDOUX, Etienne; Frere, P.; Vanbellinghen, JF.; Bruck, France; Gothot, André; HAFRAOUI, Kaoutar; Fillet, Georges; Beguin, Yves <br/> <br/>Abstract: Background: Results of nonmyeloablative HCT in pts with HLA-mismatched donors have been disappointing due to high incidence of graft rejection and severe acute GVHD. Recent studies have suggested that infusion of mesenchymal stem cells (MSC) the day of HCT might promote engraftment and prevent acute GVHD after myeloablative allogeneic HCT. However, some studies suggested that MSC co-infusion might abrogate graft-versus-host alloreactivity and graft-versus-tumor effects. This prompted us to investigate whether MSC infusion a few hours before HCT could allow nonmyeloablative HCT from HLA-mismatched donors to be performed safely (i.e. with a 100-day incidence of nonrelapse mortality < 35%). Methods: 20 patients with hematological malignancies were given MSC (1-2 x 10E6 cells/kg) from third party donors a few hours before PBSC from HLA-mismatched unrelated donors, after conditioning with 2 Gy TBI and fl udarabine 90 mg/m. Postgrafting immunosuppression included tacrolimus (day -3 to +180; tapered by day +365) and mycophenolate mofetil (tid days 0 to +42). HLA-compatibility was assessed at the HLA-A, -B, -C, -DRBI and DQBI loci: 13 pairs were mismatched for at least one HLA class I antigen (including 4 pairs who were also mismatched for 1 HLA-class II antigens (n=3) or 1 HLA-class I allele (n=1)), 1 pair was mismatched for 2 HLA class II alleles, while 6 pairs were mismatched for a single HLA class I (n=3) or HLA class II (n=3) alleles. Results: Median follow-up for surviving patients was 288 (range, 76-571) days. One patient with secondary AML had primary graft rejection, while the remaining 19 patients had sustained engraftment. Median donor T-cell chimerism levels on days 28, 100, 180 and 365 after HCT were 90%, 98%, 96%, and 98%, respectively. Grade II, III and IV acute GVHD were seen in 5, 2 and 1 patients, respectively, while 7 experienced NIH moderate/severe chronic GVHD. Three of 7 patients with measurable disease at transplantation achieved complete remission on days 41, 104 and 353 after HCT. Two patients died of nonrelapse causes on days 74 and 114 after HCT, while 3 died of disease progression. Projected 1-yr overall and progressionfree survivals were 77% and 61%, respectively. Conclusions: HLA-mismatched nonmyeloablative HCT with MSC co-infusion appeared to be safe, with MSC co-infusion possibly mitigating graft-versus-host alloreactivity without abrogating graft-versus-tumor effects. Survival is encouraging. Wed, 13 Mar 2013 15:47:56 GMT http://hdl.handle.net/2268/144723 Title: Assessing donor chimerism level among CD3 T, CD4 T, CD8 T, and NK cells predicts subsequent graft rejection, GVHD, and relapse after allogeneic HCT with nonmyeloablative conditioning <br/> <br/>Author, co-author: Baron, Frédéric; Storb, R.; Gooley, T.; Sandmaier, B.; Gisburne, S.; Shin, S.; Stroup, P.; Baker, J.; Maris, M.; Maloney, D.; Heimfeld, S.; Grumet, F.C.; Chauncey, T.; Blume, K.; Little, M.T. <br/> <br/>Abstract: We previously showed that low levels of day-14 CD3 T and NK (CD56) cells donor chimerism predicted graft rejection, whereas high levels of day-28 CD3 T-cell donor chimerism predicted acute graft-versus-host disease (GVHD) after HCT with nonmyeloablative conditioning. Here we investigate whether assessing chimerism levels among CD4 T cells and CD8 T cells, and also the absolute number of lymphocyte subsets of donor and host origins, would lend greater precision to our initial observations. We analyzed data from 157 patients receiving HCT after conditioning with 2 Gy TBI +/− fludarabine as treatment for AML (n= 22), ALL (n= 4), CML (n= 13), CLL (n= 19), MDS (n= 26), MM (n= 24), NHL (n= 30), HD (n= 14), RCC (n= 4), and WASP deficiency (n= 1). Postgrafting immunosuppression included MMF and CSP. A total of 97 patients received grafts from HLA-identical siblings, and 60 patients received grafts from HLA-matched unrelated donors. Lymphocyte subsets were isolated from peripheral blood by flow cytometry on days 14, 28, and 42. The proportion of cells of donor origin (chimerism levels) were assessed by VNTR-PCR and quantified by phosphor imaging. Eighteen patients (11%) had graft rejection. Day-14 donor chimerism levels< 50% among CD3 T (P =.0007), CD4 T (P =.03), and NK cells (P =.003) but not CD8 T cells predicted graft rejection. High absolute numbers of CD3 T (P =.002) and NK cells (P= .002) of host origin on day 14 were each associated with increased risks of graft rejection when treated as continuous linear variables. Grades 2, 3, and 4 acute GVHD were seen in 40%, 9%, and 5% of patients, respectively. High donor chimerism levels on day 14 among CD3 T (P= .02), CD4 T (P =.03), and CD8 T cells (P =.02) but not NK cells were each associated with increased risks of grades 2–4 acute GVHD. High absolute numbers of CD4 T (P =.04) and CD8 T cells (P =.04) of donor origin on days 14–42 were each associated with increased risks of grade 2–4 acute GVHD when treated as continuous linear variables, whereas high donor CD3 T (P= .002), CD8 T (P= .006), and NK cell (P= .002) chimerism levels from days 14–42 were associated with decreased risks of relapse. No statistically significant correlations between absolute numbers of donor cells and risks of relapse were found. These data suggest that assessing CD3, CD4, CD8, and NK cell donor chimerism levels and determining absolute numbers of CD3 and NK cells of host and donor origins are useful for predicting HCT outcomes after nonmyeloablative conditioning. Wed, 13 Mar 2013 15:47:16 GMT http://hdl.handle.net/2268/144697 Title: Impact of bone marrow-derived mesenchymal stromal cells on experimental xenogeneic graft-versus-host disease <br/> <br/>Author, co-author: Bruck, France; Belle, Ludovic; LECHANTEUR, Chantal; de Leval, Laurence; Hannon, Muriel; DUBOIS, Sophie; CASTERMANS, Emilie; Humblet-Baron, Stéphanie; Rahmouni, Souad; Beguin, Yves; BRIQUET, Alexandra; Baron, Frédéric <br/> <br/>Abstract: Background aims. Graft-versus-host disease (GVHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation caused by donor T cells reacting against host tissues. Previous studies have suggested that mesenchymal stromal cells (MSCs) could exert potent immunosuppressive effects. Methods. The ability of human bone marrow derived MSCs to prevent xenogeneic GVHD in non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice and in NOD/SCID/interleukin-2Rg(null) (NSG) mice transplanted with human peripheral blood mononuclear cells (PBMCs) was assessed. Results. Injection of 200 106 human PBMCs intraperitoneally (IP) into sub-lethally (3.0 Gy) irradiated NOD/SCID mice also given anti-asialo GM1 antibodies IP 1 day prior and 8 days after transplantation induced lethal xenogeneic GVHD in all tested mice. Co-injection of 2 106 MSCs IP on day 0 did not prevent lethal xenogeneic GVHD induced by injection of human PBMCs. Similarly, injection of 30 106 human PBMCs IP into sub-lethally (2.5 Gy) irradiated NSG mice induced a lethal xenogeneic GVHD in all tested mice. Injection of 3 106 MSCs IP on days 0, 7, 14 and 21 did not prevent lethal xenogeneic GVHD induced by injection of human PBMCs. Conclusions. Injection of MSCs did not prevent xenogeneic GVHD in these two humanized mice models. Wed, 13 Mar 2013 12:49:51 GMT http://hdl.handle.net/2268/144696 Title: What is the role for donor NK cells after nonmyeloablative conditioning ? <br/> <br/>Author, co-author: Baron, Frédéric; Petersdorf, Effie; Sandmaier, Brenda; Gooley, Ted; Malkki, Mari; Maloney, David; Storb, Rainer <br/> <br/>Abstract: Background: The potential role of donor NK cells after nonmyeloablative conditioning for allogeneic hematopoietic cell transplantation (HCT) is not defined. We investigated the impact of the kinetics of donor NK cell engraftment as well as the impact of missing recipient KIR ligands and the number of donor inhibitory and activating KIR genes on HCT outcomes in 282 patients (153 with HLA-matched related donors and 129 with unrelated donors) conditioned with 2 Gy TBI +/– fludarabine. Postgrafting immunosuppression consisted of cyclosporine and mycophenolate mofetil. Diagnoses were hematological malignancies (n=274) or solid tumors (8). Methods: NK cells were isolated from peripheral blood by flow cytometry on days 14, 28 and 42 after HCT. The proportions of cells of donor and host origin were assessed by FISH or by VNTR-PCR. High-resolution HLA-typing was performed using oligonucleotide probe and/or direct sequencing methods. Donor KIR genotyping was performed using a commercial PCR-SSP kit (Invitrogen) following manufacturers protocol. Results: High numbers of T (P=0.01) and CD34+ (P=0.009) cells in the graft, as well as lower numbers of donor inhibitory KIR genes (P=0.01) were each associated with higher levels of donor NK cell chimerism. There was a suggestion of an association between lower numbers of activating KIR genes and higher CD56 chimerism, however this was not statistically significant. NK cell chimerism levels were comparable in patients who had all KIR ligands present vs. in those who were missing any ligand, and there was no association between the specific missing ligand and NK chimerism. A day-14 NK cell chimerism level of < 50% was associated with increased risks of graft rejection (P=.009). Modeling chimerism levels as a continuous linear variable, there was no association between NK cell chimerism levels on day 14 and occurrence of grade II-IV acute GVHD. In contrast, high levels of donor NK cell chimerism on days 14–42 were associated with a lower risk of relapse (P=0.006) and better progression-free survival (P=0.003) in time-dependent analyses. The qualitative associations between donor NK cell chimerism and graft rejection, GVHD, relapse or progression-free survival did not change after adjustment for the presence of recipient KIR ligands nor after adjustment for the number of donor inhibitory or activating KIR genes. Finally, the 3-year cumulative incidence of relapse was 42% in patients who have all ligand for donor NK cell KIR, versus 38% in patients who miss one or more ligand for donor NK cell KIR (adjusted hazard ratio = 1.05; 95% confidence interval 0.65–1.68; p=0.85). Conclusions: Robust engraftment of donor NK cells correlated with low risk of graft rejection, low risk of relapse and high progression-free survival but not with acute GVHD. The clinical importance of donor KIR inhibitory and activating genes on post-transplant donor NK chimerism merits further study. Footnotes Disclosure: Off Label Use: Fludarabine, Mycophenolate mofetil, Cyclosporine. Wed, 13 Mar 2013 12:48:31 GMT http://hdl.handle.net/2268/144695 Title: Impact of chronic graft-versus-host disease (GVHD) after reduced intensity conditioning (RIC) allogeneic stem cell transplantation (allo-SCT) as treatment for acute myeloid leukemia (AML) : a survey from the Acute Leukemia Working Party of the EBMT <br/> <br/>Author, co-author: Baron, Frédéric; Labopin, Myriam; Niederwieser, Dietger; Milpied, Noel-Jean; Cornelissen, Jan; Malm, Claes; Vindelov, Lars; Blaise, Didier; Janssen, Jeroen; Petersen, Eefke; Socie, Gérard; Vanderson, Rocha; Nagler, Arnon; Mohty, Mohamad <br/> <br/>Abstract: The goal of RIC allo-SCT is to harness the graft-versus-leukemia (GVL) effect, while minimizing toxicities and the risk of GVHD. However, prior studies have shown a lower risk of relapse in AML patients (pts) who experienced chronic GVHD after RIC allo-SCT versus in those who did not. Here, we investigated the impact of occurrence of GVHD on transplantation outcomes in a large cohort of AML pts given allogeneic PBSC after RIC conditioning. Data from 1859 AML pts in first (n=1439) or second (n=420) CR transplanted between 2000 and 2009 following a RIC regimen at EBMT affiliated centres were analyzed. Pts were given PBSC from HLA-identical sibling (MRD, n=1208), or from HLA-matched unrelated donors (MUD, n=651). Median pt age at transplantation was 56 y (range, 18–77). 338 male pts were given grafts from female donors. RIC was based on low-dose TBI in 520 (28%) pts, while the remaining pts received chemotherapy-based RIC. ATG was given in 269 (22%) MRD and in 267 (41%) MUD recipients, respectively, while 151 (13%) MRD and 165 (25%) MUD recipients received in-vivo T cell depletion with alemtuzumab. The impact of chronic GVHD on relapse risk, non-relapse mortality (NRM), leukemia-free survival (LFS), and overall survival (OS) was assessed using time-dependent multivariate Cox models and in a landmark analysis at 18 months after transplant. Three-year incidences of relapse, NRM, LFS and OS were 34±1%, 15±1%, 51±2% and 60±2% in MRD recipients, respectively, and 34±2% (p=NS), 24±2% (P<0.001), 42±2% (P=0.001) and 47±2% (P=0.001) in MUD recipients, respectively. Grade II, III and IV acute GVHD were observed in 133 (11%), 61 (5%) and 30 (2%) MRD recipients and in 119 (18%), 41 (6%) and 24 (4%) MUD recipients, respectively. The 3-y cumulative incidence of chronic GVHD was 47%. Fifty-three percent of patients with chronic GVHD had extensive chronic GVHD, while the remaining 47% had limited chronic GVHD. In multivariate analyses, occurrence of grade II-IV acute GVHD was associated with a lower risk of relapse (HR=0.8; P=0.04), a higher risk of chronic (HR=2.2; P<0.001) and extensive chronic GVHD (HR=2.8; P<0.001), a higher risk of NRM (HR=2.4 P<0.001), a worsened LFS (HR=1.3; P=0.01), and a worsened OS (HR=1.5; P<0.001). In multivariate time-dependent analyses, occurrence of limited chronic GVHD was associated with a lower risk of relapse (HR=0.7; P=0.05), comparable NRM (HR=1.4; P=0.16), comparable LFS (HR=0.9; P=0.29) and better OS (HR=0.5; P<0.001), while occurrence of extensive chronic GVHD was associated with a lower risk of relapse (HR=0.6; P=0.01), higher NRM (HR=3.2; P<0.001), a trend for worsened LFS (HR=1.3; P=0.06) and comparable OS (HR=0.9; P=0.34). The median interval from transplantation to occurrence of chronic GVHD was 163 (range, 100–1545) days. To further assess the graft-versus-leukemia effect of chronic GVHD, we performed a landmark analysis in patients who were leukemia-free at 18 months after transplantation (n=776). Median follow-up from this landmark time-point was 24 (range, 0.1–112) months. Two-year relapse, NRM, LFS and OS were 16±2%, 2.5±1%, 82±2%, and 89±2%, respectively, in patients without chronic GVHD before the landmark time-point, versus 9±1% (P=0.001), 8±1% (P<0.001), 83±2% (P=0.65), and 86±2% (P=0.38), respectively, in patients with chronic GVHD before the landmark time-point.In conclusion, in this cohort of AML patients transplanted in remission, occurrence of chronic GVHD was associated with a lower risk of relapse that translated to better OS in patients with limited chronic GVHD but not in those with extensive chronic GVHD who experienced higher long term NRM, highlighting the need for long term prospective assessment of long term effects and quality of life in patients receiving RIC allo-SCT. Wed, 13 Mar 2013 12:47:54 GMT http://hdl.handle.net/2268/144694 Title: Kinetics of IL-7 and IL-15 Levels after Allogeneic Peripheral Blood Stem Cell Transplantation following Nonmyeloablative Conditioning <br/> <br/>Author, co-author: De Bock, Muriel; Fillet, Marianne; Hannon, Muriel; Seidel, Laurence; Merville, Marie-Paule; Gothot, André; Beguin, Yves; Baron, Frédéric <br/> <br/>Abstract: Background: We analysed kinetics of IL-7 and IL-15 levels in 70 patients given peripheral blood stem cells after nonmyeloablative conditioning. Methods: EDTA-anticoagulated plasma and serum samples were obtained before conditioning and about once per week after transplantation until day 100. Samples were aliquoted and stored at 280uC within 3 hours after collection until measurement of cytokines. IL-7 and IL-15 levels were measured by ELISAs. Results: Median IL-7 plasma levels remained below 6 pg/L throughout the first 100 days, although IL-7 plasma levels were significantly higher on days 7 (5.1 pg/mL, P = 0.002), 14 (5.2 pg/mL, P,0.001), and 28 (5.1 pg/mL, P = 0.03) (but not thereafter) than before transplantation (median value of 3.8 pg/mL). Median IL-15 serum levels were significantly higher on days 7 (12.5 pg/mL, P,0.001), 14 (10.5 pg/mL, P,0.001), and 28 (6.2 pg/mL, P,0.001) than before transplantation (median value of 2.4 pg/mL). Importantly, IL-7 and IL-15 levels on days 7 or 14 after transplantation did not predict grade II–IV acute GVHD. Conclusions: These data suggest that IL-7 and IL-15 levels remain relatively low after nonmyeloablative transplantation, and that IL-7 and IL-15 levels early after nonmyeloablative transplantation do not predict for acute GVHD. Wed, 13 Mar 2013 12:47:05 GMT http://hdl.handle.net/2268/144678 Title: Graft-versus-tumor effects after allogeneic hematopoietic cell transplantation with nonmyeloablative conditioning <br/> <br/>Author, co-author: Baron, Frédéric; Maris, Michael; Sandmaier, Brenda; Storer, Barry; Sorror, Mohamed; diaconescu, Razvan; Woolfrey, Ann; Chauncey, Thomas; Flowers, Marry; Mielcarek, Marco; Maloney, David; Storb, Rainer <br/> <br/>Abstract: We have used a nonmyeloablative conditioning regimen consisting of 2 Gy total body irradiation +/– fludarabine, 30 mg/m²/day x 3 days, to condition elderly or ill patients (pts) with hematological malignancies for allogeneic hematopoietic cell transplantation (HCT). This approach relies almost exclusively on graft-versus-tumor (GVT) effects for control of malignancy. Here, we analyzed GVT effects in 322 pts with hematological malignancies given grafts from HLA-matched related (n=192) or unrelated (n=130) donors. Grades I, II, III and IV acute GVHD were seen in 26 (8.1%), 141 (43.8%), 34 (10.6%) and 11 (3.4%) pts, respectively. Extensive chronic GVHD was seen in 181 (56.2%) pts and of these, 64 (19.9%) cases had de novo chronic GVHD. Putative GVT effects were evaluated using time-dependent Cox regression models. Of the 221 pts with measurable disease at HCT, 126 (57%) achieved complete (n=98) or partial (n=28) remissions. Multivariate analysis identified chemosensitivity for B-cell malignancies (p=.02), and tandem autologous/allogeneic HCT (p=.04) as pre-transplant factors associated with higher probabilities of achieving complete remissions (CR) after HCT. After adjusting for these factors, acute GVHD of any grade was not found to be associated with an increased probability of achieving CR. There was a trend for a higher probability of achieving CR in pts with chronic GVHD (p=.07). Progression/relapse was observed in 108 pts. Multivariate analysis identified that lower disease-risk (p=.0004), tandem autologous/allogeneic HCT (p=.02) and adapted Charlson comorbidity index (CCI) score at transplant < 3 (p=.002) resulted in significantly decreased risk of progression/relapse. After correcting for these factors, extensive chronic GVHD was associated with a decreased risk of progression/relapse (p=.006). Pts with grade 1 acute GVHD tended to have less progression/relapse (p=.07). Conversely, grade II–IV acute GVHD did not significantly affect the risk of progression/relapse. Nonrelapse mortality was observed in 70 pts. Multivariate analysis showed that lower disease-risk (p=. 001), tandem autologous/allogeneic HCT (p=.002) and CCI score at transplant < 3 (p<.0001) significantly decreased nonrelapse mortality. After adjusting for these variables, grade II (p=.04) and grade III–IV (p<.0001) acute GVHD increased nonrelapse mortality while extensive chronic GVHD did not. The 3-year probability of progression-free survival (PFS) was 38.5%. In multivariate analysis, lower disease-risk (p<.0001), tandem autologous/allogeneic HCT (p=.0008) and CCI score at transplant < 3 (p<.0001) resulted in significantly better PFS. After adjusting for theses variables, grade 1 acute GVHD (p=.02) and chronic extensive GVHD (p=.003) were both associated with significantly better PFS, while grade III–IV acute GVHD (p<.0001) was associated with decreased PFS. In summary, chronic GVHD in pts given nonmyeloablative conditioning was associated with substantial GVT effects which led to improved PFS. Conversely, any potential GVT benefits from grade II–IV acute GVHD were offset by higher nonrelapse mortality resulting in worse PFS. Efforts should be directed at reducing the risk of grade II–IV acute GVHD while allowing de novo chronic GVHD for best PFS after allogeneic HCT with nonmyeloablative conditioning. Wed, 13 Mar 2013 10:26:28 GMT http://hdl.handle.net/2268/144659 Title: Utilisation de la transfusion par les services cliniques en 2011 en RD Congo : leçons à tirer <br/> <br/>Author, co-author: Kapinga, Suzanne; Kazadi, Rigobert; Munlemvo Mavanga, Nana; Misingi, Pacifique Tue, 12 Mar 2013 23:45:06 GMT