0000000000284992

AUTHOR

Shahrzad Bakhtiar

Long-Term Outcome of Preemptive Immunotherapy Based on Post-Transplant Chimerism and MRD Monitoring after Allogeneic Stem Cell Transplantation in Children with Acute Lymphoblastic Leukemia: A Single Center Experience

Abstract Introduction: Mixed chimerism (MC) and minimal residual disease (MRD) strongly predict risk for relapse in children with acute lymphoblastic leukemia (ALL) following allogeneic stem cell transplantation (allo-SCT). Preemptive immunotherapy (IT), e.g. withdrawal of immunosuppression (WD-IS) or donor lymphocyte infusion (DLI) guided by chimerism and MRD monitoring can prevent impending relapse in allo-SCT recipients. In this study we retrospectively analyzed chimerism and MRD monitoring and the effect of preemptive IT in all pts undergoing allo-SCT for ALL in our institution. Patients: Between January 2005 and July 2014, a total of 89 children and adolescents (median age 11.5; range …

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Characterization of the Clinical and Immunologic Phenotype and Management of 157 Individuals with 56 Distinct Heterozygous NFKB1 Mutations

Contains fulltext : 229571.pdf (Publisher’s version ) (Closed access) BACKGROUND: An increasing number of NFKB1 variants are being identified in patients with heterogeneous immunologic phenotypes. OBJECTIVE: To characterize the clinical and cellular phenotype as well as the management of patients with heterozygous NFKB1 mutations. METHODS: In a worldwide collaborative effort, we evaluated 231 individuals harboring 105 distinct heterozygous NFKB1 variants. To provide evidence for pathogenicity, each variant was assessed in silico; in addition, 32 variants were assessed by functional in vitro testing of nuclear factor of kappa light polypeptide gene enhancer in B cells (NF-κB) signaling. RESU…

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Pre-Emptive Immunotherapy for Clearance of Molecular Disease in Childhood Acute Lymphoblastic Leukemia after Transplantation

Abstract Monitoring of minimal residual disease (MRD) or chimerism may help guide pre-emptive immunotherapy (IT) with a view to preventing relapse in childhood acute lymphoblastic leukemia (ALL) after transplantation. Patients with ALL who consecutively underwent transplantation in Frankfurt/Main, Germany between January 1, 2005 and July 1, 2014 were included in this retrospective study. Chimerism monitoring was performed in all, and MRD assessment was performed in 58 of 89 patients. IT was guided in 19 of 24 patients with mixed chimerism (MC) and MRD and by MRD only in another 4 patients with complete chimerism (CC). The 3-year probabilities of event-free survival (EFS) were .69 ± .06 for …

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Treatment of relapse after allogeneic stem cell transplantation in children and adolescents with ALL: the Frankfurt experience

Therapy for post-transplant relapse of paediatric ALL is limited. Standardised curative approaches are not available. We hereby describe our local procedure in this life-threatening situation. A total of 101 ALL patients received their first allogeneic stem cell transplantation (SCT) in our institution. After relapse, our primary therapeutic goal was to cure the patient with high-dose chemotherapy or specific immunotherapy (HDCHT/SIT) followed by a second SCT from a haploidentical donor (transplant approach). If this was not feasible, low-dose chemotherapy and donor lymphocyte infusions (LDCHT+DLI) were offered (non-transplant approach). A total of 23 patients suffered a post-transplant rel…

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A PCR-Based Assay for the Detection of Langerhans-Cell Chimerism after Allogeneic Stem Cell Transplantation.

Abstract Early acute GVHD of the skin frequently occurs in patients after allogeneic hematopoietic stem cell transplantation. Although T cell depletion reduces the incidence and severity, it does not completely prevent skin GVHD. This leads to a prolonged need for immunosuppressive medication in a significant number of patients. For the induction of acute GVHD, the stimulation of donor T cells by residing host antigen presenting cells such as Langerhans cells of the skin (LCs) plays a central role. The absence of donor T cells after depletion, however, seems to hamper an early switch of LCs from host to donor origin. Therefore, the monitoring of LC chimerism is of great interest. We and oth…

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