Search

Although high-dose therapy and autologous stem cell transplant combined with novel agents continues to be the hallmark of first-line treatment in newly diagnosed transplant-eligible multiple myeloma patients, the impact of tandem autologous or autologous/reduced-intensity allogeneic transplant for patients with extramedullary disease (EMD) and high-risk cytogenetics is not yet defined. Here, we analyzed clinical and cytogenetic data from 488 adult myeloma patients with EMD undergoing single autologous (n = 373), tandem autologous (n = 84), or autologous-allogeneic transplant (n = 31) between 2003 and 2015. At least 1 high-risk abnormality was present in 41% (n = 202), with del(17p) (40%) and t(4;14) (45%) the most frequent. More than 1 high-risk abnormality was found in 54%. High-risk cytogenetics showed worse 4-year overall survival (OS) and progression-free survival (PFS) of 54% and 29%, respectively, versus 78% and 49% for standard-risk cytogenetics (P < .001). Co-segregation of high-risk abnormalities did not seem to affect outcome. Regarding transplant regimen, OS and PFS were 70% and 43% for single autologous versus 83% and 52% for tandem autologous and 88% and 58% for autologous-allogeneic (P = .06 and P = .30). In multivariate analysis high-risk cytogenetics were associated with worse survival (hazard ratio [HR], 2.00; P = .003), whereas tandem autologous significantly improved outcome versus single autologous transplant (HRs, .46 and .64; P = .02 and P = .03). Autologous-allogeneic transplant did not significantly differ in outcome but appeared to improve survival, but results were limited because of small population (HR, .31). In conclusion, high-risk cytogenetics is frequently observed in newly diagnosed myeloma with EMD and significantly worsens outcome after single autologous, whereas a tandem autologous transplant strategy may overcome onset poor prognosis., (Copyright © 2019 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Strategies for relapse prevention after allogeneic transplantation in acute leukaemia are warranted. A registry-based matched-pair analysis evaluated the efficacy of prophylactic donor lymphocyte infusion (proDLI). Adults receiving proDLI in complete remission (CR) and controls were pair-matched for age, diagnosis, cytogenetics, stage, donor, gender, conditioning and T-cell depletion. Eighty-nine pairs were identified (median follow-up: 6.9 years). Within the entire cohort, no difference was observed. However, among patients with high-risk acute myeloid leukaemia (AML) (unfavourable cytogenetics and/or transplanted beyond first CR), proDLI recipients had improved overall survival (69.8% vs. 40.2% in controls, P = 0.027). ProDLI has moderate efficacy, but can contribute to improved outcome in high-risk AML., (© 2018 British Society for Haematology and John Wiley & Sons Ltd.)

Allogeneic stem cell transplantation (allo-SCT) can be a curative treatment for patients with a hematologic malignancy due to alloreactive T cell responses recognizing minor histocompatibility antigens (MiHA). Yet tumor immune escape mechanisms can cause failure of T cell immunity, leading to relapse. Tumor cells display low expression of costimulatory molecules and can up-regulate coinhibitory molecules that inhibit T cell functionality on ligation with their counter-receptors on the tumor-reactive T cells. The aim of this explorative study was to evaluate immune checkpoint expression profiles on T cell subsets and on cytomegalovirus (CMV)- and/or MiHA-reactive CD8 + T cells of allo-SCT recipients using a 13-color flow cytometry panel, and to correlate these expression patterns to clinical outcomes. MiHA-reactive CD8 + T cells exhibited an early differentiated CD27 ++ /CD28 ++ phenotype with low KLRG-1 and CD57 expression. These T cells also displayed increased expression of PD-1, TIM-3, and TIGIT compared with total effector memory T cells and CMV-specific CD8 + T cells in healthy donors and allo-SCT recipients. Remarkably, high coexpression of PD-1, TIGIT, and KLRG-1 on MiHA-reactive CD8 + T cells was associated with relapse after allo-SCT. Taken together, these findings indicate that MiHA-specific CD8 + T cells of relapsed patients have a distinctive coinhibitory expression signature compared with patients who stay in remission. This phenotype may serve as a potential monitoring tool in patients. Moreover, these findings suggest that PD-1 and TIGIT play important roles in regulating T cell-mediated tumor control, providing a rationale for immunotherapy with blocking antibodies to treat relapse after allo-SCT., (Copyright © 2017 The American Society for Blood and Marrow Transplantation. All rights reserved.)

Allogeneic stem cell transplantation (allo-SCT) with or without donor lymphocyte infusions (DLI) is the only curative option for several hematological malignancies. Unfortunately, allo-SCT is often associated with GvHD, and patients often relapse. We therefore aim to improve the graft-versus-tumor effect, without increasing the risk of GvHD, by targeting hematopoietic lineage-restricted and tumor-associated minor histocompatibility antigens using peptide-loaded dendritic cell (DC) vaccinations. In the present multicenter study, we report the feasibility, safety and efficacy of this concept. We treated nine multiple myeloma patients with persistent or relapsed disease after allo-SCT and a previous DLI, with donor monocyte-derived mHag-peptide-loaded DC vaccinations combined with a second DLI. Vaccinations were well tolerated and no occurrence of GvHD was observed. In five out of nine patients, we were able to show the induction of mHag-specific CD8 + T cells in peripheral blood. Five out of nine patients, of which four developed mHag-specific T cells, showed stable disease (SD) for 3.5-10 months. This study shows that mHag-based donor monocyte-derived DC vaccination combined with DLI is safe, feasible and capable of inducing objective mHag-specific T-cell responses. Future research should focus on further improvement of the vaccination strategy, toward translating the observed T-cell responses into robust clinical responses.

Background: Leukemia recurrence is a major cause of treatment failure after autologous stem cell transplantation for acute myeloid leukemia (AML). It usually occurs within the first 2 years after transplantation. The goal of the current retrospective study was to assess the follow-up of and characterize risk factors for outcome among patients who survived free of disease recurrence after this period., Methods: The analysis included 3567 adults (median age, 45 years) with AML who underwent autografting during the first (86% of patients) or second (14% of patients) complete remission between 1990 and 2008. The stem cell source was the bone marrow in 32% of patients or the peripheral blood in 68% of patients. The median follow-up was 6.9 years., Results: At 5 years and 10 years after transplantation, the probability of leukemia-free survival was 86% and 76%, respectively; the recurrence incidence was 11% and 16%, respectively; and the nonrecurrence mortality rate was 3% and 8%, respectively. The observed survival was decreased compared with the expected survival of the general European population. In a multivariate analysis, decreased probability of leukemia-free survival was demonstrated for patients who underwent peripheral blood autologous stem cell transplantation; had French-American-British subtypes M0, M6, or M7; and were of an older age. The same factors were found to be associated with an increased risk of disease recurrence. Nonrecurrence mortality was found to be affected by older age., Conclusions: The results of the current analysis indicate that late recurrences remain a major concern after autologous stem cell transplantation among patients with AML, indicating the need for close monitoring of minimal residual disease and additional leukemic control measures after transplantation. Cancer 2016;122:1880-7. © 2016 American Cancer Society., (© 2016 American Cancer Society.)

Allo-SCT followed by DLIs can establish long-term remissions in multiple myeloma (MM) patients. In many patients, however, the immunotherapeutic graft-versus-tumor (GVT) effect is moderate and not sustained, implying that immune suppression is mediated, among other factors, by regulatory T cells (Tregs) or myeloid-derived suppressor cells (MDSCs). Towards a better understanding and, eventually, manipulation of the immune-regulatory mechanisms in transplanted MM patients, we retrospectively sought a correlation between DLI outcome and circulating CD14(+) MDSCs, CD14(-) MDSCs and Tregs in 53 MM patients before their first DLI. We found significantly elevated frequencies of highly suppressive CD14(+) MDSCs, CD14(-) MDSCs and Tregs in pre-DLI samples from patients. Higher frequencies of Tregs, but not of MDSCs, were significantly associated with non-responsiveness to DLI. Furthermore, a lower frequency of Tregs predicted the development of chronic GVHD, which, in turn, displayed a high association with GVT. Elevated Treg frequencies before DLI were also associated with significantly shorter PFS and OS. Hence, our data reinforce the idea of active suppression of antitumor responses by Tregs in MM patients and therefore suggest that targeting patient Tregs before DLI may improve outcome of DLI.

We investigated whether a young human leukocyte antigen (HLA)-matched unrelated donor (MUD) should be preferred as donor to an HLA-identical sibling (MRD) for older patients with myelodysplastic syndrome (MDS) (≥ 50 years) who underwent allogeneic stem cell transplantation (AHSCT). Outcomes of 719 MDS patients with a median age of 58 years (range, 50-73 years) who received AHSCT from related (n=555) or unrelated (n=164) donors between 1999 and 2008 and reported to the European Group for Blood and Marrow Transplantation were analyzed. The median donor age of the MRD was 56 years (range: 35-78), in contrast to 34 years (range: 19-64) for the MUDs. Influence of donor's age on survival was not observed for MRD (hazard ratio (HR): 1.01 (95% confidence interval (CI): 0.99-1.02), P=0.2), but there was a significant impact of MUD's age on outcome (HR: 1.03 (95% CI: 1.01-1.06); P=0.02). Transplantation from younger MUDs (<30 years) had a significant improved 5-year overall survival in comparison with MRD and older MUDs (>30 years): 40% vs 33% vs 24% (P=0.04). In a multivariate analysis, AHSCT from young MUD (<30 years) remained a significant factor for improved survival in comparison with MRD (HR: 0.65 (95% CI: 0.45-0.95), P=0.03), which should be considered in donor selection for older patients.

Allogeneic stem cell transplantation (SCT) is a potentially curative treatment for patients with hematologic malignancies. Its therapeutic effect is largely dependent on recognition of minor histocompatibility antigens (MiHA) by donor-derived CD8⁺ T cells. Therefore, monitoring of multiple MiHA-specific CD8⁺ T cell responses may prove to be valuable for evaluating the efficacy of allogeneic SCT. In this study, we investigated the use of the combinatorial encoding MHC multimer technique to simultaneously detect MiHA-specific CD8⁺ T cells in peripheral blood of SCT recipients. Feasibility of this approach was demonstrated by applying dual-color encoding MHC multimers for a set of 10 known MiHA. Interestingly, single staining using a fluorochrome- and Qdot-based five-color combination showed comparable results to dual-color staining for most MiHA-specific CD8⁺ T cell responses. In addition, we determined the potential value of combinatorial encoding MHC multimers in MiHA identification. Therefore, a set of 75 candidate MiHA peptides was predicted from polymorphic genes with a hematopoietic expression profile and further selected for high and intermediate binding affinity for HLA-A2. Screening of a large cohort of SCT recipients resulted in the detection of dual-color encoded CD8⁺ T cells following MHC multimer-based T cell enrichment and short ex vivo expansion. Interestingly, candidate MiHA-specific CD8⁺ T cell responses for LAG3 and TLR10 derived polymorphic peptides could be confirmed by genotyping of the respective SNPs. These findings demonstrate the potency of the combinatorial MHC multimer approach in the monitoring of CD8⁺ T cell responses to known and potential MiHA in limited amounts of peripheral blood from allogeneic SCT recipients.

Peripheral blood used as a source of stem cells for transplantation (PBSCT) is known to exert stronger immune-mediated effects compared with BM (BMT). We decided to retrospectively analyze the impact of stem cell source on the OS of CML patients who relapsed after either matched related donor PBSCT (N=168) or BMT (N=216) and were treated with donor lymphocyte infusions (DLI). Univariate analysis revealed a lower probability of OS after DLI in patients relapsing after PBSCT vs BMT (66% vs 79% at 5 years, P=0.013). However, a multivariate Cox analysis did not reveal any significant impact of PBSCT as a risk factor for decreased OS for patients transplanted in first chronic phase (CP1; hazard ratio (HR) 1.036, 95% confidence interval (CI) 0.619-1.734). A statistical interaction term suggested that the impact of stem cell source on OS after DLI was different for those transplanted in advanced phases (negative impact of previous PBSCT-HR 2.176, 95% CI 0.930-5.091). In summary, the stem cell source does not affect the OS of CML patients who underwent PBSCT in CP1, relapsed and were treated with DLI. However, when the patients were transplanted in advanced phases, previous PBSCT seems to negatively affect OS after DLI compared with BMT. [ABSTRACT FROM AUTHOR]

Recently, we demonstrated that reduced intensity conditioning (RIC) followed by partial T-cell-depleted SCT creates a platform for inducing the graft-versus-myeloma effect by adjuvant immunotherapy. Here, we evaluated mHA-specific T-cell responses in a multiple myeloma (MM) patient who was treated with RIC-SCT followed by donor lymphocyte infusion (DLI) and subsequent recipient DC vaccination. We isolated a mHA-specific CTL clone with the capacity to target MM tumor cells from this patient experiencing long-term CR. This CTL clone recognizes an HLA-A3-restricted mHA and mediates killing of both primary MM cells and the MM-cell line U266, while BM-derived fibroblasts are not recognized. CTL-specific T-cell receptor (TCR) transcripts could be detected by quantitative PCR analysis in both peripheral blood and BM during tumor remission. Interestingly, a strong increase of CTL-specific TCR transcripts at the BM tumor site was observed following DLI and recipient DC vaccination, while the TCR signal in peripheral blood decreased. These findings illustrate that the approach of partial T-cell-depleted RIC-SCT followed by post-transplantation immunotherapy induces mHA-specific T-cell responses targeting MM tumor cells. [ABSTRACT FROM AUTHOR]

Natural killer (NK) cells have an important function in the anti-tumor response early after stem cell transplantation (SCT). As part of a prospective randomized phase III study, directly comparing the use of CD3+/CD19+-depleted peripheral blood stem cell (PBSC) harvests with CD34+-selected PBSC harvests in allogeneic human leukocyte antigen-matched SCT, we here show that the use of CD3+/CD19+-depleted PBSC grafts leads to early NK cell repopulation and reconstitution of the CD56dim and CD56bright NK cell subsets, with concomitant high cytolytic capacity. In the CD34 group, this process took significantly longer. Moreover, in the CD3/19 group after reconstitution, a higher percentage of killer immunoglobulin-like receptor-positive NK cells was found. Although similar percentages of CD94-positive NK cells were found in both groups, in the CD34 group, almost all expressed the inhibitory CD94:NKG2A complex, whereas in the CD3/19 group, the inhibitory CD94:NKG2A and the activating CD94:NKG2C complex were equally distributed. This preferential development of NKG2C-expressing NK cells in the CD3/19 group was paralleled by a loss of NKG2A-mediated inhibition of NK cell degranulation. These results show that the use of CD3+/CD19+-depleted grafts facilitates strong NK cell cytolytic responses directly after SCT, and the rapid emergence of an NK cell receptor phenotype that is more prone to activation. [ABSTRACT FROM AUTHOR]

Single nucleotide polymorphisms (SNPs) in the NOD2 gene have significant impact on both treatment-related mortality (TRM) and acute GVHD (aGVHD) in haematopoietic stem cell transplantation (HSCT). The effect of these polymorphisms when using T-cell-depleted grafts has been poorly studied. We retrospectively analysed NOD2 polymorphisms in a cohort of 85 patients and donors who received an HLA-identical sibling partially T-cell-depleted HSCT (0.5 × 106 CD3+ T cells per kg) following idarubicin-containing conditioning regimens. NOD2 polymorphisms were present in 14 of 85 (16.5%) of patients and 18 of 85 (21%) of donors. The risk of severe aGVHD (grade III–IV) and the 1-year TRM was significantly higher in the presence of NOD2 polymorphisms (hazard ratio (HR) 6.0, P=0.02 for severe aGVHD and HR 3.3, P=0.02 for TRM, respectively) and was most prominent in cases where patient and donor both had a polymorphism (HR 10.5, P=0.002 and HR 3.9, P=0.002). There was also a trend towards increased risk of bacteraemia due to coagulase-negative staphylococci in patients with an NOD2 polymorphism. We conclude that NOD2 polymorphism screening should be used to optimize donor selection and antimicrobial prophylaxis to reduce the occurrence of aGVHD and TRM following allogeneic HSCT. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the role of pre-emptive donor lymphocyte infusion (pDLI) after partial T-cell-depleted allogeneic SCT in patients with multiple myeloma (MM). A cohort of 24 MM patients was treated with partial T-cell-depleted myeloablative SCT between December 1997 and April 2002. These patients were intended to receive pDLI after SCT. The overall response rate after SCT was 83% (20 of 24 patients) with 10 patients (42%) in complete remission (CR). Transplant-related mortality within 1 year after SCT was 29%. Thirteen patients (54%) received pDLI and four patients in partial remission reached CR. GVHD>grade I after pDLI developed in 4 out of 13 patients (30%). Four patients received therapeutic DLI, without preceding pDLI. Eleven patients (46%) are alive, with a median follow-up of 67 months (range, 48–100 months). Seven of these patients (29%) are in continuous CR (CCR), which was confirmed by a negative patient-specific IgH PCR in four patients. All seven patients in CCR received pDLI. Although myeloablative SCT in MM induces high toxicity, we show that the concept of T-cell depletion followed by pDLI is promising and needs to be investigated in a reduced-intensity conditioning setting.Bone Marrow Transplantation (2007) 40, 355–359; doi:10.1038/sj.bmt.1705742; published online 11 June 2007 [ABSTRACT FROM AUTHOR]

Using red cell phenotyping (RCP) and/or cytogenetics (CYT) we identified 19 patients with persisting mixed chimerism (MC) among 231 patients transplanted with partially T cell-depleted stem cell grafts from HLA-identical siblings. Persisting MC is defined as MC for more than 2 years in patients without any evidence of relapse. Median leukemia-free survival in these patients was 150 (range, 50-218) months. Diagnoses were ALL (n = 10); AML (n = 2); CML (n = 2); NHL (n = 2); MDS (n = 1); MM (n = 1) and SAA (n = 1). Purpose of this study was the longterm follow-up of MC and definition of patterns of chimerism in the various subsets of PBMCs and granulocytes. Using a PCRSTR technique CD3[sup +]/CD4[sup +] (T4 lymphocytes), CD3[sup +]/CD8[sup +] (T8 lymphocytes), CD45[sup +]/CD19[sup +] (B lymphocytes), CD45[sup +]/CD14[sup +] (monocytes), CD45[sup +]/CD15[sup +] (granulocytes) and CD3[sup -]/CD56[sup +] (NKcells) were analyzed. The majority of patients with persisting MC were conditioned with a less intensive conditioning regimen and had little GVHD. Sequential monitoring of the chimerism resulted in a group of patients (n = 7) with very slow transient mixed chimerism that resulted in complete DC after median 7 years. Another nine patients had a relatively high percentage of persisting autologous cells for a median of 12 years and in three patients we observed a stable low percentage of autologous cells. Only two out of 19 patients (AML-CR1, CML-CP1) relapsed during follow-up. Both patients had a relatively high percentage of autologous cells. Chimerism in granulocytes and PBMC subsets was analyzed at a median of 8 years after SCT in nine patients. In five patients mixed chimerism simultaneously detected by RCP and CYT was associated with MC in all subsets. Within each individual patient the percentages of donor and recipient cells were very different between the different subsets. Two CML-CP1 patients were mixed chimera in only two subsets and in one patient these... [ABSTRACT FROM AUTHOR]