Superior Graft-versus-Leukemia Effect Associated with Transplantation of Haploidentical Compared with HLA-Identical Sibling Donor Grafts for High-Risk Acute Leukemia: An Historic Comparison
ABSTRACT The outcomes of an historic comparison of 117 consecutive, high-risk, acute leukemia patients undergoing hematopoietic stem cell transplantation (HSCT) from HLA-mismatched/haploidentical donors (HID, n = 81) or HLA-identical sibling donors (ISD, n = 36) without the use of in vitro T cell depletion (TCD), between the period of January 2005 and April 2009 were compared. Full engraftment was achieved in 98% of patients in the HID group and 97% in the ISD group. The cumulative incidences of grades II-IV acute graft-versus-host disease (aGVHD) in the HID and ISD cohorts were 49% and 24%, respectively (P = .014) with a relative risk (RR) of 2.99 (1.25-7.21) (P = .014). The incidence of chronic GVHD (cGVHD) did not differ significantly between the 2 cohorts. The 2-year cumulative incidence of relapse was significantly lower in HID (26%) than in ISD patients (49%) (P = .008). The 2-year cumulative incidence of nonrelapse mortality (NRM) was comparable in recipients of HID (34%) and ISD grafts (38%) (P = .85). The 3-year probability of overall survival (OS) was higher in HID patients (42%) than in ISD (20%) (P = .048) patients. Our comparisons suggest that HID transplants can achieve a stronger graft-versus-leukemia (GVL) effect than ISD for high-risk acute leukemia patients.
Conference Paper: A 10-bit pipelined ADC for high speed, low power applications[Show abstract] [Hide abstract]
ABSTRACT: A pipelined ADC is presented in which the key component, the comparator, is designed using a latch structure which decreases the settling time and minimizes static power dissipation. Offset errors caused by device mismatch are cancelled using an autozeroing technique. The gain cell and subtractor is designed using a differential mode source follower to maximize the speed and minimize the power consumption and die area. The automatic gain calibration scheme is addressed. The circuit implementation enables operation at a 20 MHz sampling rate with only 25 mW average power dissipation. It achieves 10-bit resolution with the die area being less than 0.8 mm<sup>2</sup> in a 0.8 μm technologySignals, Systems & Computers, 1997. Conference Record of the Thirty-First Asilomar Conference on; 12/1997
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ABSTRACT: Haploidentical stem cell transplantation is an attractive form of transplantation because of the immediate donor availability, ease of stem cell procurement, and the possibility to further collect donor cells for cellular therapy. Historically, maintaining T cells in the graft has been associated with very high rates of graft-versus-host-disease (GVHD), whereas T cell-depleted haploidentical transplantation has been limited by a higher incidence of graft rejection and nonrelapse mortality related to infectious complications as a result of delayed immune reconstitution posttransplantation. Recent approaches have attempted to eliminate the alloreactive T cells to prevent GVHD posttransplantation. Administration of high-dose cyclophosphamide early posttransplantation in combination with tacrolimus and mycophenolate mofetil has produced engraftment and GVHD rates similar to HLA-matched sibling transplants, suggesting that the most important barriers against successful haploidentical transplantation can be overcome. Future directions should focus on optimizing conditioning regimens for different diseases and prevention of disease relapse posttransplantation.Biology of blood and marrow transplantation: journal of the American Society for Blood and Marrow Transplantation 08/2011; 18(3):372-80. DOI:10.1016/j.bbmt.2011.08.001 · 3.35 Impact Factor
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ABSTRACT: Hematopoietic stem cell transplantation provides the only potential curative option in many patients with hematological malignancies. Finding a suitably matched donor in a timely manner is often difficult. However, most patients have a partially HLA-mismatched (HLA-haploidentical) first-degree relative readily available. Historically, HLA-haploidentical bone marrow transplantation (BMT) has been considered extremely high risk due to high rates of life-threatening graft-versus-host disease (GVHD) and non-relapse mortality (NRM). Modifications of the stem cell graft, such as T-cell depletion, have resulted in poor rates of engraftment. We have recently completed a phase II clinical trial of nonmyeloablative HLA-haploidentical hematopoietic BMT followed by post-transplantation high-cyclophosphamide. High-dose cyclophosphamide has been shown to create immunogenic tolerance by specifically killing activated mature T-cells. As a result, alloreactive T-cells in the donor graft are selectively destroyed thereby decreasing the incidence of severe GVHD. As well, host-versus-graft reactive T-cells are also selectively eliminated thereby increasing rates of engraftment. Among 210 patients with hematological malignancies receiving nonmyeloablative, HLA-haploidentical BMT with post-transplantation cyclophosphamide, the rate of sustained donor cell engraftment has been 87%. The cumulative incidence of grade 2-4 acute GVHD is 27%, grade 3-4 acute GVHD is 5% and chronic GVHD is 15%. Interestingly, increasing HLA disparity between donor and recipient was not associated with increasing incidence of GVHD or decreased event-free survival. Nonmyeloablative haploidentical stem cell transplantation with post-transplantation cyclophosphamide seems to be a promising, potentially curative, option for patients with hematological malignancies who either lack an HLA-matched related or unrelated donor, or in whom a myeloablative preparative regimen is contraindicated due to significant co-morbidities or history of extensive pre-treatment.Best practice & research. Clinical haematology 09/2011; 24(3):359-68. DOI:10.1016/j.beha.2011.05.001 · 2.55 Impact Factor