Pretransplantation Therapy with Hypomethylating Agents in Patients with Myelodysplastic Syndromes Receiving Reduced-Intensity Conditioning Regimens

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Human cytomegalovirus-specific CD4+ and CD8+ T-cell reconstitution in adult allogeneic hematopoietic stem cell transplant recipients and immune control of viral infection

Background Human cytomegalovirus infection is the most frequent viral complication in patients undergoing hematopoietic stem cell transplantation. We investigated the development of human cytomegalovirus-specific T cells in adult recipients of hematopoietic stem cell transplants. Design and Methods From May 2003 through October 2006 a total of 45 patients were monitored for human cytomegalovirus-specific T-cell reconstitution. Human cytomegalovirus-infected autologous dendritic cells were used as a stimulus to detect interferon-γ-producing human cytomegalovirus-specific CD8+ and CD4+ T cells during the first year after transplantation. Interleukin-2 production by specific T cells was also determined. ![Figure 1.][1] Figure 1. Probability of HCMV infection development and HCMV-specific CD4+ and CD8+ T-cell immunity reconstitution. A: cumulative incidence curves of HCMV infection according to donor (D) and recipient (R) HCMV-serostatus. B: cumulative incidence curves of HCMV infection and HCMV-specific CD8+ and CD4+ T-cell reconstitution (i.e. corresponding to a specific T-cell number greater than 0.4 cells/μL blood). C: cumulative incidence curves of HCMV-specific CD8+ T-cell reconstitution according to D/R HCMV-serostatus. D: cumulative incidence curves of HCMV-specific CD4+ T-cell reconstitution according to D/R HCMV-serostatus. Results Human cytomegalovirus infection was detected in the blood of 39/45 patients at a median of 29 days after transplantation. Human cytomegalovirus-specific T-cell reconstitution followed reactivation of latent human cytomegalovirus infection at a median time of about 2 months after transplantation. Only donor human cytomegalovirus-seronegativity and bone marrow as a stem cell source were found to delay specific T-cell reconstitution significantly. Levels of three CD8+ and one CD4+ human cytomegalovirus-specific T-cells/μL blood had a positive predictive value of around 80% for identifying patients able to control human cytomegalovirus infection spontaneously. Five patients who received high doses of steroids for treatment of graft-versus-host disease developed human cytomegalovirus infection requiring pre-emptive treatment despite high levels of interferon-γ-producing T cells in response to human cytomegalovirus. Specific interleukin-2 production was not detected in patients with human cytomegalovirus infection requiring treatment, while 90% of patients who spontaneously controlled human cytomegalovirus infection had T cells that produced interleukin-2 and interferon-γ. Conclusions Pre-transplant human cytomegalovirus infection of the recipient is a major factor driving human cytomegalovirus-specific immune reconstitution. Control of human cytomegalovirus infection likely requires the presence of both interferon-γ and interleukin-2 producing T cells. Corticosteroid treatment may favor active viral replication even in patients with specific T cells. [1]: pending:ye

Antithymocyte globulin for graft-versus-host disease prophylaxis in transplants from unrelated donors: 2 randomized studies from Gruppo Italiano Trapianti Midollo Osseo (GITMO)

Abstract One hundred nine patients with hematologic malignancies, undergoing bone marrow transplants (BMT) from unrelated donors, were randomized in 2 consecutive trials to receive or not to receive antithymocyte globulin (ATG) in the conditioning regimen, as follows: (A) 54 patients (median age, 28 years; 39% with advanced disease) were randomized to no ATG (n = 25) versus 7.5 mg/kg rabbit ATG (Thymoglobulin; Sangstat, Lyon, France) (n = 29) ; (B) 55 patients (median age, 31 years, 71% with advanced disease) were randomized to no ATG (n = 28) versus 15 mg/kg rabbit ATG (n = 27). Grade III-IV graft-versus-host disease (GVHD) was diagnosed in 36% versus 41% (P = .8) in the first and in 50% versus 11% (P = .001) in the second trial. Transplant-related mortality (TRM), relapse, and actuarial 3-year survival rates were comparable in both trials. In fact, despite the reduction of GVHD in the second trial, a higher risk for lethal infections (30% vs 7%; P = .02) was seen in the arm given 15 mg/kg ATG. Extensive chronic GVHD developed overall more frequently in patients given no ATG (62% vs 39%;P = .04), as confirmed by multivariate analysis (P = .03). Time to 50 × 109/L platelets was comparable in the first trial (21 vs 24 days; P = .3) and delayed in the ATG arm in the second trial (23 vs 38 days;P = .02). These trials suggest that (1) 15 mg/kg ATG before BMT significantly reduces the risk for grade III-IV acute GVHD, (2) this does not translate to a reduction in TRM because of the increased risk for infections, and (3) though survival is unchanged, extensive chronic GVHD is significantly reduced in patients receiving ATG

Reconstitution of Human Cytomegalovirus-Specific CD4+ T Cells is Critical for Control of Virus Reactivation in Hematopoietic Stem Cell Transplant Recipients but Does Not Prevent Organ Infection

The relative contribution of human cytomegalovirus (HMCV)-specific CD4(+) and CD8(+) T cells to the control of HCMV infection in hematopoietic stem cell transplant (HSCT) recipients is still controversial. HCMV reactivation and HCMV-specific CD4(+) and CD8(+) T cell reconstitution were monitored for 1 year in 63 HCMV-seropositive patients receiving HSCT. HCMV reactivation was detected in all but 2 patients. In 20 of 63 (31.7%) patients (group 1) HCMV infection resolved spontaneously, whereas 32 of 63 (50.8%) patients (group 2) controlled the infection after a single short-course of pre-emptive therapy and the remaining 9 (14.3%) patients (group 3) suffered from relapsing episodes of HCMV infection, requiring multiple courses of antiviral therapy. The kinetics and magnitude of HCMV-specific CD8(+) T cell reconstitution were comparable among the 3 groups, but HCMV-specific CD4(+) T cells were lower in number in patients requiring antiviral treatment. HCMV-seronegative donors, as well as unrelated donors (receiving antithymocyte globulin) and acute graft-versus-host disease (GVHD) were associated with both delayed HCMV-specific CD4(+) T cell reconstitution and severity of infection. Conversely, these risk factors had no impact on HCMV-specific CD8(+) T cells. Eight patients with previous GVHD suffered from HCMV gastrointestinal disease, although in the presence of HCMV-specific CD4(+) and CD8(+) systemic immunity and undetectable HCMV DNA in blood. Reconstitution of systemic HCMV-specific CD4(+) T cell immunity is required for control of HCMV reactivation in adult HSCT recipients, but it may not be sufficient to prevent late-onset organ localization in patients with GVHD. HCMV-specific CD8(+) T cells contribute to control of HCMV infection, but only after HCMV-specific CD4(+) T cell reconstitution

Allogeneic hsct with reduced intensity conditioning regimens in high risk patients with myelofibrosis

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A Modified Post-Transplant Cyclophosphamide Regimen, for Unmanipulated Haploidentical Marrow Transplantation, in Acute Myeloid Leukemia: A Multicenter Study

Abstract We report a modified post-transplant cyclophosphamide (PT-CY) regimen, for unmanipulated haploidentical marrow transplants, in 150 patients with acute myeloid leukemia (AML). All patients received a myeloablative regimen, cyclosporine A (CsA) on day 0, mycophenolate on day +1, and PT-CY 50 mg/kg on days +3 and +5. The median age was 51 (range, 17–74) years, 51 (34%) patients had active disease at transplant, and the median follow-up of surviving patients 903 (range, 150-1955) days. The cumulative incidence (CI) of engraftment, acute graft-versus-host disease (GVHD) grade II to IV, and moderate/severe chronic GVHD was 92%, 17%, and 15%, respectively. The 4-year CI of transplant-related mortality (TRM) and relapse was 20% and 24%, respectively. Four-year survival for remission patients was 72% (74% versus 67% fo

Incidence, Risk Factors and Outcome of Pre-engraftment Gram-Negative Bacteremia after Allogeneic and Autologous Hematopoietic Stem Cell Transplantation: An Italian Prospective Multicenter Survey

Background Gram-negative bacteremia (GNB) is a major cause of illness and death after hematopoietic stem cell transplantation (HSCT), and updated epidemiological investigation is advisable. Methods We prospectively evaluated the epidemiology of pre-engraftment GNB in 1118 allogeneic HSCTs (allo-HSCTs) and 1625 autologous HSCTs (auto-HSCTs) among 54 transplant centers during 2014 (SIGNB-GITMO-AMCLI study). Using logistic regression methods. we identified risk factors for GNB and evaluated the impact of GNB on the 4-month overall-survival after transplant. Results The cumulative incidence of pre-engraftment GNB was 17.3% in allo-HSCT and 9% in auto-HSCT. Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa were the most common isolates. By multivariate analysis, variables associated with GNB were a diagnosis of acute leukemia, a transplant from a HLA-mismatched donor and from cord blood, older age, and duration of severe neutropenia in allo-HSCT, and a diagnosis of lymphoma, older age, and no antibacterial prophylaxis in auto-HSCT. A pretransplant infection by a resistant pathogen was significantly associated with an increased risk of posttransplant infection by the same microorganism in allo-HSCT. Colonization by resistant gram-negative bacteria was significantly associated with an increased rate of infection by the same pathogen in both transplant procedures. GNB was independently associated with increased mortality at 4 months both in allo-HSCT (hazard ratio, 2.13; 95% confidence interval, 1.45-3.13; P <.001) and auto-HSCT (2.43; 1.22-4.84; P =.01). Conclusions Pre-engraftment GNB is an independent factor associated with increased mortality rate at 4 months after auto-HSCT and allo-HSCT. Previous infectious history and colonization monitoring represent major indicators of GNB. Clinical Trials registration NCT02088840