Search results for "Stem cell transplantation"

SARS-CoV-2 vaccine response and rate of breakthrough infection in patients with hematological disorders

2022

Abstract Background The clinical efficacy of SARS-CoV-2 vaccines according to antibody response in immunosuppressed patients such as hematological patients has not yet been established. Patients and methods A prospective multicenter registry-based cohort study conducted from December 2020 to December 2021 by the Spanish transplant and cell therapy group was used to analyze the relationship of antibody response at 3–6 weeks after full vaccination (2 doses) with breakthrough SARS-CoV-2 infection in 1394 patients with hematological disorders. Results At a median follow-up of 165 days after complete immunization, 37 out of 1394 (2.6%) developed breakthrough SARS-CoV-2 infection at median of 77 …

Consequence of Histoincompatibility beyond GvH-Reaction in Cytomegalovirus Disease Associated with Allogeneic Hematopoietic Cell Transplantation: Cha…

2021

Hematopoietic cell (HC) transplantation (HCT) is the last resort to cure hematopoietic malignancies that are refractory to standard therapies. Hematoablative treatment aims at wiping out tumor cells as completely as possible to avoid leukemia/lymphoma relapse. This treatment inevitably co-depletes cells of hematopoietic cell lineages, including differentiated cells that constitute the immune system. HCT reconstitutes hematopoiesis and thus, eventually, also antiviral effector cells. In cases of an unrelated donor, that is, in allogeneic HCT, HLA-matching is performed to minimize the risk of graft-versus-host reaction and disease (GvHR/D), but a mismatch in minor histocompatibility antigens …

Re-examining the relationship between active cytomegalovirus (CMV) infection and acute graft-versus-host disease in allogeneic stem cell transplant r…

2015

Cell quality evaluation with gene expression analysis of spheroids (3D) and adherent (2D) adipose stem cells.

2021

Adipose stem cells (ASCs) represent a reliable source of stem cells with a widely demonstrated potential in regenerative medicine and tissue engineering applications. New recent insights suggest that three-dimensional (3D) models may closely mimic the native tissue properties; spheroids from adipose derived stem cells (SASCs) exhibit enhanced regenerative abilities compared with those of 2D models. Stem cell therapy success is determined by “cell-quality”; for this reason, the involvement of stress signals and cellular aging need to be further investigated. Here, we performed a comparative analysis of genes connected with stemness, aging, telomeric length and oxidative stress, in 3D and 2D …

Dynamics of Torque Teno virus plasma DNAemia in allogeneic stem cell transplant recipients

2017

Abstract Background Torque Teno virus (TTV) plasma DNA load directly correlate with the level of immunosuppresion in different clinical settings. It is uncertain whether this may be the case in allogeneic hematopoietic stem cell transplant recipients (allo-HSCT). Objectives We characterized the dynamics of TTV DNAemia in patients undergoing T-cell replete allo-SCT. Study design Retrospective single-center observational study including 72 allo-HSCT patients. Plasma TTV DNA loads were quantified before initiating the conditioning regimen and at different time-points after transplant by real-time PCR. White blood cells (WBC) and absolute lymphocyte counts (ALC) were measured by flow cytometry.…

Matching for the MICA-129 polymorphism is beneficial in unrelated hematopoietic stem cell transplantation.

2016

Major histocompatibility complex class I polypeptide-related sequence A (MICA) is a highly polymorphic ligand of the activating NKG2D receptor on natural killer (NK) cells, γδ-T cells, and NKT cells. MICA incompatibilities have been associated with an increased graft-versus-host disease (GVHD) incidence, and the MICA-129 (met/val) dimorphism has been shown to influence NKG2D signaling in unrelated hematopoietic stem cell transplantation (uHSCT). We investigated the effect of MICA matching on survival after uHSCT. We sequenced 2172 patients and their respective donors for MICA. All patients and donors were high-resolution HLA-typed and matched for 10/10 (n = 1379), 9/10 (n = 636), or 8/10 (n…

Aspergilosis invasora en el paciente con enfermedad oncohematológica

2018

Invasive aspergillosis is the most common invasive fungal infection in patients with acute hematological malignancies or treated with hematopoietic stem cell transplantation due to the marked alteration of the physiological mechanisms of antifungal immunity that takes place in these situations. For this reason, antifungal prophylaxis has a relevant role in these patients. The introduction of new antifungal agents has motivated the updating of recommendations for prophylaxis and treatment in different guidelines. The objectives of this chapter are a brief review of the mechanisms of immunity against fungi, the definition of risk for developing an invasive fungal infection and an update of th…

Bone regeneration in the stem cell era: safe play for the patient?

2017

The past decade has seen outstanding scientific progress in the field of stem cell (SC) research and clinical application. SCs are convenient both technically and biologically: they are easy to find and to culture and they can differentiate in virtually all tissues and even in whole organs. Induced pluripotent stem cells (iPSs) are a type of pluripotent SC generated in vitro directly from mature cells through the introduction of key transcription factors. The use of iPSs, however tantalizing, poses serious safety concerns because of their genomic instability. Recently, it has been suggested that the main mechanism of SC action relies on paracrine signals. Therefore, the secretome would be p…

Influence of different types of pulp treatment during isolation in the obtention of human dental pulp stem cells

2016

Background: Different methods have been used in order to isolate dental pulp stem cells. The aim of this study was to study the effect of different types of pulp treatment during isolation, under 3% O 2 conditions, in the time needed and the efficacy for obtaining dental pulp stem cells. Material and Methods: One hundred and twenty dental pulps were used to isolate dental pulp stem cells treating the pulp tissue during isolation using 9 different methods, using digestive, disgregation, or mechanical agents, or combining them. The cells were positive for CD133, Oct4, Nestin, Stro-1, CD34 markers, and negative for the hematopoietic cell marker CD-45, thus confirming the presence of mesenchyma…

HLA-DPB1 mismatch alleles represent powerful leukemia rejection antigens in CD4 T-cell immunotherapy after allogeneic stem-cell transplantation.

2016

Refractory or relapsed acute myeloid leukemia (AML) represents a frequent complication after allogeneic hematopoietic stem-cell transplantation (HSCT). We show herein that primary in vitro stimulation of CD45RA-selected CD4 T cells of stem-cell donors with 10/10 HLA-matched AML blasts results in expansion of cytolytic T-lymphocytes (CTL) that almost all recognize HLA-DPB1 mismatch alleles, which clinically occur in up to 80% of donor-patient pairs. Primary AML blasts were found to strongly express HLA-DPB1, whereas fibroblasts and keratinocytes used as surrogate target cells for graft-versus-host disease did express HLA-DPB1 only upon IFN-γ pre-treatment. Since patients' AML blasts are rare…