Development of a potency assay for CD34 cell-based therapy.

We have previously shown that intracardiac delivery of autologous CD34 cells after acute myocardial infarction (AMI) is safe and leads to long term improvement. We are now conducting a multicenter, randomized, controlled Phase I/IIb study in post-AMI to investigate the safety and efficacy of intramyocardial injection of expanded autologous CD34 cells (ProtheraCytes) (NCT02669810). Here, we conducted a series of in vitro studies characterizing the growth factor secretion, exosome secretion, gene expression, cell surface markers, differentiation potential, and angiogenic potential of ProtheraCytes clinical batches to develop a potency assay.

Transforming Perspectives in Cardiac Cell Therapy: Hypothesis and Commentary Following Updated Results of a Pilot Study Investigating Very Long-Term Clinical Outcomes in Severe AMI Patients Following Trans-Epicardial Injection of Peripheral Blood CD34 Cells.

Ischemic heart attack is the leading cause of death worldwide. Ten percent of cases will die within an hour. Of the survivors, around 30% will have suffered a severe infarction which will lead to the irreparable destruction of 1 to 2 billion myocardial cells, causing an irreversible secondary heart failure with a poor prognosis in the short.

Deciphering the Cardiovascular Potential of Human CD34 Stem Cells.

Ex vivo monitored human CD34 stem cells (SCs) injected into myocardium scar tissue have shown real benefits for the recovery of patients with myocardial infarctions. They have been used previously in clinical trials with hopeful results and are expected to be promising for cardiac regenerative medicine following severe acute myocardial infarctions. However, some debates on their potential efficacy in cardiac regenerative therapies remain to be clarified.

Evaluation of expanded peripheral blood derived CD34+ cells for the treatment of moderate knee osteoarthritis.

Knee osteoarthritis (OA) is a degenerative joint disease of the knee that results from the progressive loss of articular cartilage. It is most common in the elderly and affects millions of people worldwide, leading to a continuous increase in the number of total knee replacement surgeries. These surgeries improve the patient's physical mobility, but can lead to late infection, loosening of the prosthesis, and persistent pain.

Industrialized GMP Production of CD34 Cells (ProtheraCytes®) at Clinical Scale for Treatment of Ischemic Cardiac Diseases Is Feasible and Safe.

Regenerative medicine now needs to pass a crucial turning point, from academic research to the market. Several sources/types of cells have been experimented with, more or less successfully. CD34 cells have demonstrated multipotent or even pluripotent capacities, making them good candidates for regenerative medicine, particularly for treating heart diseases.

Differential Expression of the Tetraspanin CD9 in Normal and Leukemic Stem Cells.

CD9 plays a crucial role in cellular growth, mobility, and signal transduction, as well as in hematological malignancy. In myeloid neoplasms, CD9 is involved in the altered interactions between leukemic and stromal cells. However, apart from its role in CD34 progenitors and myeloid and megakaryocytic differentiation, its function in normal and leukemic pluripotent cells has not yet been determined.

Key Success Factors for Regenerative Medicine in Acquired Heart Diseases.

Stem cell therapy offers a breakthrough opportunity for the improvement of ischemic heart diseases. Numerous clinical trials and meta-analyses appear to confirm its positive but variable effects on heart function. Whereas these trials widely differed in design, cell type, source, and doses reinjected, cell injection route and timing, and type of cardiac disease, crucial key factors that may favour the success of cell therapy emerge from the review of their data.

Design and Validation of an Automated Process for the Expansion of Peripheral Blood-Derived CD34 Cells for Clinical Use After Myocardial Infarction.

We previously demonstrated that intracardiac delivery of autologous peripheral blood-derived CD34 stem cells (SCs), mobilized by granulocyte-colony stimulating factor (G-CSF) and collected by leukapheresis after myocardial infarction, structurally and functionally repaired the damaged myocardial area. When used for cardiac indication, CD34 cells are now considered as Advanced Therapy Medicinal Products (ATMPs). We have industrialized their production by developing an automated device for ex vivo CD34 -SC expansion, starting from a whole blood (WB) sample.

VSELs Maintain their Pluripotency and Competence to Differentiate after Enhanced Ex Vivo Expansion.

The very small embryonic-like stem cells (VSELs) are known as a subset of adult pluripotent stem cells able to differentiate to all three germ layers. However, their small number and quiescence restrict the possibility of their use in cell therapy. In the present study, we first delineate different subpopulation of VSELs from human cord blood CD34+ cells to define their purity.

Human Very Small Embryonic-Like Stem Cells Are Present in Normal Peripheral Blood of Young, Middle-Aged, and Aged Subjects.

The purpose of our study was to determine whether the number of human very small embryonic-like stem cells (huVSELs) would vary depending on the age of humans. HuVSELs frequency was evaluated into the steady-state (SS) peripheral blood (PB) of healthy volunteers using flow cytometry analysis. Their numbers were compared with volunteers' age.

Residents learning ultrasound-guided catheterization are not sufficiently skilled to use landmarks.

Introduction: Ultrasound-guided (UG) technique is the recommended procedure for central venous catheterization (CVC). However, as ultrasound may not be available in emergency situations, guidelines also propose that physicians remain skilled in landmark (LM) placement. We conducted this prospective observational study to determine the learning curve of the LM technique in residents only learning the UG technique.

Selective aminopeptidase-N (CD13) inhibitors with relevance to cancer chemotherapy.

Aminopeptidase-N (APN/CD13) is highly expressed on the surface of numerous types of cancer cells and particularly on the endothelial cells of neoangiogenic vessels during tumourigenesis. This metallo-aminopeptidase has been identified as a potential target for cancer chemotherapy. In this work, we evaluated the efficacy of a novel series of benzosuberone analogues, which were previously reported to be highly potent, selective APN inhibitors with Ki values in the micromolar to sub-nanomolar range.

Identification and isolation from either adult human bone marrow or G-CSF-mobilized peripheral blood of CD34(+)/CD133(+)/CXCR4(+)/ Lin(-)CD45(-) cells, featuring morphological, molecular, and phenotypic characteristics of very small embryonic-like (VSEL) stem cells.

Objective: Recently, we demonstrated that normal human bone marrow (hBM)-derived CD34(+) cells, released into the peripheral blood after granulocyte colony-stimulating factor mobilization, contain cell subpopulations committed along endothelial and cardiac differentiation pathways. These subpopulations could play a key role in the regeneration of post-ischemic myocardial lesion after their direct intracardiac delivery. We hypothesized that these relevant cells might be issued from very small embryonic-like stem cells deposited in the BM during ontogenesis and reside lifelong in the adult BM, and that they could be mobilized into peripheral blood by granulocyte colony-stimulating factor.

Valvular heart disease associated with benfluorex therapy: results from the French multicentre registry.

Aims: The aim of this paper is to report clinical characteristics, consequences, echocardiographic features, and pathological findings encountered in patients suffering from valvular disease associated with benfluorex exposure in a multicentre French registry.

Methods And Results: Forty patients suffering from unexplained restrictive valvular disease with a previous exposition to benfluorex, a fenfluramine derivative, were identified from eight French university hospitals. Patients were mostly women (87.

Restrictive organic mitral regurgitation associated with benfluorex therapy.

Aims: To investigate the association between benfluorex use and organic restrictive mitral regurgitation (MR) in patients admitted to hospital for diagnostic work-up of MR of unclear aetiology.

Methods And Results: Among patients referred between 2003 and 2008 to our tertiary centre for diagnostic work-up of MR, we retrospectively identified 22 consecutive patients (65 +/- 12 years, 64% women) with restrictive organic MR of unclear aetiology. Using propensity scores, 22 out of 156 patients who underwent surgery for dystrophic MR due to flail leaflets during the same time period were matched for age, sex, height, body weight, and diabetes with the study population.

Long-term benefit of intracardiac delivery of autologous granulocyte-colony-stimulating factor-mobilized blood CD34+ cells containing cardiac progenitors on regional heart structure and function after myocardial infarct.

Background Aims: Starting from experimental data proposing hematopoietic stem cells as candidates for cardiac repair, we postulated that human peripheral blood (PB) CD34+ cells mobilized by hematopoietic growth-factor (G-CSF) would contain cell subpopulations capable of regenerating post-ischemic myocardial damages.

Methods: In a phase I clinical assay enrolling seven patients with acute myocardial infarct, we directly delivered to the injured myocardium autologous PB CD34+ cells previously mobilized by G-CSF, collected by leukapheresis and purified by immunoselection. In parallel, we looked for the eventual presence of cardiomyocytic and endothelial progenitor cells in leukapheresis products of these patients and controls, using flow cytometry, reverse transcription-quantitative (RTQ)-polymerase chain reaction (PCR), cell cultures and immunofluorescence analyzes.

Three-dimensional distribution patterns of CD34 antigen on nonactivated cord blood cells.

Circulating immature blood cells are inhomogeneous in most cytometric parameters, including CD34 expression. This surface antigen forms patches, and we studied their spatial distribution pattern by processing staggered and digitalized microscopical images; the number, fluorescence intensity, and volume were determined in randomly identified CD34-positive cord blood cells in suspension. Quantitative fluorescence analysis of individual CD34-labeled cells was performed after acquisition of microscopical images in high resolution by using a CCD camera and adjacent deconvolution.

Peripheral blood and BM CD34+ CD38- cells show better resistance to cryopreservation than CD34+ CD38+ cells in autologous stem cell transplantation.

Background: We and others have shown a critical role for CD34+ CD38- cells in hematopoietic recovery after autologous stem cell transplantation (ASCT), in particular for platelet reconstitution. Thus a routine assessment of CD34+ CD38- cells in freezing-thawing procedures for autografting could represent an important tool for predicting poor engraftment.

Methods: To compare the impact of cryopreservation on CD34+ CD38+ and CD34+ CD38- hematopoietic stem cell subsets, 193 autograft products collected in 84 patients with malignancies were assessed before controlled-rate cryopreservation in 10% DMSO and after thawing for autografting.

CD34+ cells and CD34+CD38- subset from mobilized blood show different patterns of adhesion molecules compared to those from steady-state blood, bone marrow, and cord blood.

As suggested previously, a down-regulation of some cellular adhesion molecules (CAMs) on CD34(+) hematopoietic progenitor cells (HPC) may contribute to their egress from bone marrow (BM) to peripheral blood (PB) by decreasing their adhesion to BM stromal cells. Besides counting the percentage of CAM-positive cells, we decided to define clearly the antigen density (AgD) of the CAM on mobilized- and steady-state CD34(+) HPC using QIFIKIT calibration beads. Five sources of cells were compared: PB and BM from normal donors (nPB, nBM) cord blood (CB), mobilized PB obtained from leukapheresis products (LKP), and mobilized BM (mBM) samples.

Human embryonic or adult stem cells: an overview on ethics and perspectives for tissue engineering.

Over the past few years, research on animal and human stem cells has experienced tremendous advances which are almost daily loudly revealed to the public on the front-page of newspapers. The reason for such an enthusiasm over stem cells is that they could be used to cure patients suffering from spontaneous or injuries-related diseases that are due to particular types of cells functioning incorrectly, such as cardiomyopathy, diabetes mellitus, osteoporosis, cancers, Parkinson's disease, spinal cord injuries or genetic abnormalities. Currently, these diseases have slightly or non-efficient treatment options, and millions of people around the world are desperately waiting to be cured.

Cell surface CD43 determination improves diagnostic precision in late B-cell diseases.

Panels of immunological markers are useful in refining diagnosis in view of certain variability between B-cell leukaemias. A statistical multivariate approach was used on 100 B leukaemias (preliminary sample) to explore the potential value of the combination of CD43, and the classical markers CD5, CD23, CD79b, FMC7, CD22 and surface immunoglobulin to differentiate chronic lymphoid leukaemia (CLL) from lymphoma (non-CLL). CD43 was highly effective (P < 0.