Systemic Dysfunction of Osteoblast Differentiation in Adipose-Derived Stem Cells from Patients with Multiple Myeloma.

multiple myeloma; bone disease; osteogenesis; adipogenesis; adipose-derived stem cells; bone marrow; senescence; Dickkopf-related protein 1; systemic disease.

[In vitro generation of blood red cells from stem cells: a sketch of the future].

Human adult pluripotent stem cells, stem cells of embryonic origin and induced pluripotent stem cells (iPS) provide cellular sources for new promising regenerative medicine approaches. Because these cells can be patient-specific, they allow considering a personalized medicine appropriate to the diagnosis of each. The generation of cultured red blood cells (cRBC) derived from stem cells is emblematic of personalized medicine.

A novel micronucleus in vitro assay utilizing human hematopoietic stem cells.

The induction of micronucleated reticulocytes in the bone marrow is a sensitive indicator of chromosomal damage. Therefore, the micronucleus assay in rodents is widely used in genotoxicity and carcinogenicity testing. A test system based on cultured human primary cells could potentially provide better prediction compared to animal tests, increasing patient safety while also implementing the 3Rs principle, i.

Molecular signature of erythroblast enucleation in human embryonic stem cells.

While enucleation is a critical step in the terminal differentiation of human red blood cells, the molecular mechanisms underlying this unique process remain unclear. To investigate erythroblast enucleation, we studied the erythroid differentiation of human embryonic stem cells (hESCs), which provide a unique model for deeper understanding of the development and differentiation of multiple cell types. First, using a two-step protocol, we demonstrated that terminal erythroid differentiation from hESCs is directly dependent on the age of the embryoid bodies.

Caspase-3 is involved in the signalling in erythroid differentiation by targeting late progenitors.

A role for caspase activation in erythroid differentiation has been established, yet its precise mode of action remains elusive. A drawback of all previous investigations on caspase activation in ex vivo erythroid differentiation is the lack of an in vitro model producing full enucleation of erythroid cells. Using a culture system which renders nearly 100% enucleated red cells from human CD34(+) cells, we investigated the role of active caspase-3 in erythropoiesis.

[Red blood cell production for transfusion purposes. A stem cell ex vivo fate].

In vitro generation of red blood cells (RBC) makes sense in a context of recurrent shortage. It could be an interesting complementary source for "classic" transfusion products by combining the sufficiency of supply, homemade production of a particular phenotype of interest and reduced risk of infection. The question that arises is how to produce in vitro RBC? Here we retrace the steps that led to the production of functional RBC, from basic knowledge of in vivo erythropoiesis to in vitro generation of RBC from different sources of stem cells.

In vitro generated Rh(null) red cells recapitulate the in vivo deficiency: a model for rare blood group phenotypes and erythroid membrane disorders.

Lentiviral modification combined with ex vivo erythroid differentiation was used to stably inhibit RhAG expression, a critical component of the Rh(rhesus) membrane complex defective in the Rh(null) syndrome. The cultured red cells generated recapitulate the major alterations of native Rh(null) cells regarding antigen expression, membrane deformability, and gas transport function, providing the proof of principle for their use as model of Rh(null) syndrome and to investigate Rh complex biogenesis in human primary erythroid cells. Using this model, we were able to reveal for the first time that RhAG extinction alone is sufficient to explain ICAM-4 and CD47 loss observed on native Rh(null) RBCs.

Human induced pluripotent stem cells can reach complete terminal maturation: in vivo and in vitro evidence in the erythropoietic differentiation model.

Background: Human induced pluripotent stem cells offer perspectives for cell therapy and research models for diseases. We applied this approach to the normal and pathological erythroid differentiation model by establishing induced pluripotent stem cells from normal and homozygous sickle cell disease donors.

Design And Methods: We addressed the question as to whether these cells can reach complete erythroid terminal maturation notably with a complete switch from fetal to adult hemoglobin.

Human fetal liver: an in vitro model of erythropoiesis.

We previously described the large-scale production of RBCs from hematopoietic stem cells (HSCs) of diverse sources. Our present efforts are focused to produce RBCs thanks to an unlimited source of stem cells. Human embryonic stem (ES) cells or induced pluripotent stem cell (iPS) are the natural candidates.

Proof of principle for transfusion of in vitro-generated red blood cells.

In vitro RBC production from stem cells could represent an alternative to classic transfusion products. Until now the clinical feasibility of this concept has not been demonstrated. We addressed the question of the capacity of cultured RBCs (cRBCs) to survive in humans.

Red blood cells from induced pluripotent stem cells: hurdles and developments.

Purpose Of Review: In the context of chronic blood supply difficulties, generating cultured red blood cells (cRBCs) in vitro after amplification of stem cells makes sense. This review will focus on the recent findings about the generation of erythroid cells from induced pluripotent stem (iPS) cells and deals with the hurdles and next developments that will occur.

Recent Findings: The most proliferative source of stem cells for generating cRBCs is the cord blood, but this source is limited in terms of hematopoietic stem cells and dependent on donations.

The impact of bleeding history, von Willebrand factor and PFA-100(®) on the diagnosis of type 1 von Willebrand disease: results from the European study MCMDM-1VWD.

The relationships between the Platelet Function Analyzer (PFA)-100 and von Willebrand factor (VWF) levels and bleeding score (BS) were evaluated within a multicentre project on Molecular and Clinical Markers for the Diagnosis and Management of type 1 von Willebrand disease (MCMDM-1VWD). PFA-100 closure time, either with epinephrine (EPI) or adenosine diphosphate (ADP)-cartridges, was measured in 107 index cases, 105 affected and 71 unaffected family members, and 79 healthy controls. By regression analysis VWF levels were strongly related to both closure times, with a non-linear progression.

Red blood cell generation from human induced pluripotent stem cells: perspectives for transfusion medicine.

Background: Ex vivo manufacture of red blood cells from stem cells is a potential means to ensure an adequate and safe supply of blood cell products. Advances in somatic cell reprogramming of human induced pluripotent stem cells have opened the door to generating specific cells for cell therapy. Human induced pluripotent stem cells represent a potentially unlimited source of stem cells for erythroid generation for transfusion medicine.

Unimpaired terminal erythroid differentiation and preserved enucleation capacity in myelodysplastic 5q(del) clones: a single cell study.

Background: Anemia is a characteristic of myelodysplastic syndromes, such as the rare 5q- syndrome, but its mechanism remains unclear. In particular, data are lacking on the terminal phase of differentiation of erythroid cells (enucleation) in myelodysplastic syndromes.

Design And Methods: We used a previously published culture model to generate mature red blood cells in vitro from human hematopoietic progenitor cells in order to study the pathophysiology of the 5q- syndrome.

Expression of 14 von Willebrand factor mutations identified in patients with type 1 von Willebrand disease from the MCMDM-1VWD study.

Background: Candidate von Willebrand factor (VWF) mutations were identified in 70% of index cases in the European study 'Molecular and Clinical Markers for the Diagnosis and Management of type 1 von Willebrand Disease'. The majority of these were missense mutations.

Objectives: To assess whether 14 representative missense mutations are the cause of the phenotype observed in the patients and to examine their mode of pathogenicity.

Selected Stro-1-enriched bone marrow stromal cells display a major suppressive effect on lymphocyte proliferation.

Mesenchymal stem cells (MSCs) have an immunosuppressive effect and can inhibit the proliferation of alloreactive T cells in vitro and in vivo. Cotransplantation of MSCs and hematopoietic stem cells (HSCs) from HLA-identical siblings has been shown to reduce the incidence of acute graft-vs.-host disease.

Leukemia inhibitory factor: Role in human mesenchymal stem cells mediated immunosuppression.

The interactions between mesenchymal stem cells (MSCs) and immune system are currently being explored. Leukemia inhibitory factor (LIF) is linked to regulatory transplantation tolerance. Our aim was to study the expression of LIF on human MSCs at both gene and protein level in mixed lymphocyte reaction (MSC/MLR), and its implication in MSC immunosuppressive effect.

Identification of type 1 von Willebrand disease patients with reduced von Willebrand factor survival by assay of the VWF propeptide in the European study: molecular and clinical markers for the diagnosis and management of type 1 VWD (MCMDM-1VWD).

The decreased survival of von Willebrand factor (VWF) in plasma has been implicated as a mechanism in a subset of type 1 von Willebrand disease (VWD) patients. We have previously reported that the ratio of plasma levels of VWF and its propeptide (VWFpp) can be used to identify patients with reduced VWF survival. In this study, we report the assay of VWFpp and VWF:Ag in 19 individuals recruited from 6 European centers within the MCMDM-1VWD study.

Detailed von Willebrand factor multimer analysis in patients with von Willebrand disease in the European study, molecular and clinical markers for the diagnosis and management of type 1 von Willebrand disease (MCMDM-1VWD).

Background: Type 1 von Willebrand disease (VWD) is a congenital bleeding disorder characterized by a partial quantitative deficiency of plasma von Willebrand factor (VWF) in the absence of structural and/or functional VWF defects. Accurate assessment of the quantity and quality of plasma VWF is difficult but is a prerequisite for correct classification.

Objective: To evaluate the proportion of misclassification of patients historically diagnosed with type 1 VWD using detailed analysis of the VWF multimer structure.

Response to desmopressin is influenced by the genotype and phenotype in type 1 von Willebrand disease (VWD): results from the European Study MCMDM-1VWD.

We have prospectively evaluated the biologic response to desmopressin in 77 patients with type 1 von Willebrand disease (VWD) enrolled within the Molecular and Clinical Markers for the Diagnosis and Management of type 1 VWD project. Complete response to desmopressin was defined as an increase of both ristocetin cofactor activity (VWF:RCo) and factor VIII coagulant activity (FVIII:C) to 50 IU/dL or higher and partial response as VWF:RCo or FVIII:C lower than 50 IU/dL after infusion, but at least 3-fold the basal level. Complete response was observed in 83% of patients; partial in 13%; and no response in 4%.

Mesenchymal stem cell abnormalities in patients with multiple myeloma.

Osteolytic bone lesions are common in patients with multiple myeloma (MM), a clonal plasma cell disorder, and result from increased osteoclastic bone resorption and decreased osteoblastic bone formation. Because mesenchymal stem cells (MSCs) are committed towards cells of the osteoblast lineage, we compared the in vitro characteristics of MSCs from the bone marrow of 18 MM patients (MM-MSCs) and eight normal donors (ND-MSCs). MM-MSCs displayed deficient growth that could be explained in part by the reduced expression of several growth factor receptors on the surface of MM-MSCs compared with ND-MSCs.

Immunosuppressive effects of mesenchymal stem cells: involvement of HLA-G.

Introduction: Mesenchymal stem cells (MSCs) possess unique immunomodulatory properties. They are able to suppress allogenic T-cell response and modify maturation of antigen-presenting cells. Their role in the treatment of severe graft versus host disease has been reported.

Identification of IL-10 and TGF-beta transcripts involved in the inhibition of T-lymphocyte proliferation during cell contact with human mesenchymal stem cells.

Mesenchymal stem cells (MSC) inhibit the response of allogeneic T lymphocytes in culture. Because the mechanisms of this effect may differ according to the existence of cell contact, we investigated the differences in gene expression of inhibitory molecules during MSC-T lymphocyte coculture when cell contact does and does not occur. Human MSC and T lymphocytes were cultured together in standard and transwell cultures.

Mutational analysis of the von Willebrand factor gene in type 1 von Willebrand disease using conformation sensitive gel electrophoresis: a comparison of fluorescent and manual techniques.

Two versions of conformation sensitive gel electrophoresis, fluorescent (F-CSGE) and manual (M-CSGE) techniques, were compared for mutation analysis of the von Willebrand factor gene. 56 PCRs were used to amplify all 52 exons of the gene in seven type 1 von Willebrand disease cases, plus a healthy control. One hundred and ninety-two samples were analyzed on each F-CSGE gel, compared with 40 on M-CSGE.