Fully automated, clinical-grade bone marrow processing: a single-centre experience.

BACKGROUND: Clinical grade processing of harvested bone marrow is required in various clinical situations, particularly in the management of ABO mismatching in allogeneic haematopoietic stem cell transplantation (HSCT) and in regenerative medicine. MATERIAL AND METHODS: We report a single-centre experience using a fully automated, clinical grade, closed system (Sepax, Biosafe, Switzerland). From 2003 to 2015, 125 procedures were performed in our laboratory, including buffy-coat production for HSCT (n=58), regenerative medicine in an orthopaedic setting (n=54) and density-gradient separation in a trial for treatment of critical limb ischaemia (n=13). RESULTS: Buffy coat separation resulted in a median volume reduction of 85% (range, 75-87%), providing satisfactory red blood cell depletion (69%, range 30-88%) and a median recovery of CD34 cells of 96% (range, 81-134%) in the setting of allogeneic HSCT. Significantly greater volume reduction (90%; range, 90-92%) and red blood cell depletion (88%; range, 80-93%) were achieved by the new SmartRedux software released for Sepax2, validated in the last eight allogeneic HSCT. The density gradient separation programme resulted in complete red blood cell depletion associated with high CD34 recovery (69%; range, 36-124%). No reactions related to the quality of the product were reported. Time to engraftment following allogeneic HSCT was in the normal range. No cases of microbiological contamination related to the manipulation were reported. DISCUSSION: Clinical grade, automated bone marrow manipulation with Sepax was shown to be effective, giving operator-independent results and could be used for a broad range of clinical applications.

Kinetics of the use of cryopreserved autologous stem cell grafts: a GITMO-SIDEM survey.

BACKGROUND AIMS: Hematopoietic stem cell cryopreservation significantly contributed to autologous stem cell transplantation (ASCT). Cryopreserved stem cell units (SCU) are expected to be used soon after harvesting for most purposes, but, in a number of cases, they remain stored for some time, creating an increasing load for SCU depositories. Disposal policies vary widely in each center, and the existing guidelines are insufficient. METHODS: We conducted a survey of seven Gruppo Italiano Trapianto di Midollo Osseo centers to investigate the outcome of SCU harvested from January 2005 to December 2009 for ASCT. The data from 1603 collections were gathered, for a total of 5822 SCU. RESULTS: In our cohort, 79% of patients collected >5 × 106 CD34+ cells/kg, and 3.4% collected <2 × 106 CD34+ cells/kg. Up to 21% of all the patients and 42% of those with acute leukemia did not undergo reinfusion, and 37% of the cryopreserved SCU were excess, resulting from patients not reinfusing or partially reinfusing. Less than one-third of the excess SCU was disposed, and the major causes of disposal were death and, in a minority of cases, withdrawal of the indication for ASCT. In our analysis, very few first reinfusions occurred after 2 years, and those after 5 years were exceptional. Through the use of a multivariate analysis, we sought to identify the risk factors for collection non-use, independent of the centers' policies. Non-use of SCU was significantly associated with patients with acute leukemia, collections of <2 × 106 CD34/kg and lower age groups. CONCLUSIONS: These data serve as a valid basis to support rational recommendations for cost-effective storage and disposal of SCU.

Bone marrow-derived mesenchymal stem cells from early diffuse systemic sclerosis exhibit a paracrine machinery and stimulate angiogenesis in vitro.

OBJECTIVE: To characterise bone marrow-derived mesenchymal stem cells (MSCs) from patients with systemic sclerosis (SSc) for the expression of factors implicated in MSC recruitment at sites of injury, angiogenesis and fibrosis. The study also analysed whether the production/release of bioactive mediators by MSCs were affected by stimulation with cytokines found upregulated in SSc serum and tissues, and whether MSCs could modulate dermal microvascular endothelial cell (MVEC) angiogenesis. METHODS: MSCs obtained from five patients with early severe diffuse SSc (SSc-MSCs) and five healthy donors (H-MSCs) were stimulated with vascular endothelial growth factor (VEGF), transforming growth factor ß (TGFß) or stromal cell-derived factor-1 (SDF-1). Transcript and protein levels of SDF-1 and its receptor CXCR4, VEGF, TGFß(1) and receptors TßRI and TßRII were evaluated by quantitative real-time PCR, western blotting and confocal microscopy. VEGF, SDF-1 and TGFß(1) secretion in culture supernatant was measured by ELISA. MVEC capillary morphogenesis was performed on Matrigel with the addition of MSC-conditioned medium. RESULTS: In SSc-MSCs the basal expression of proangiogenic SDF-1/CXCR4 and VEGF was significantly increased compared with H-MSCs. SSc-MSCs constitutively released higher levels of SDF-1 and VEGF. SDF-1/CXCR4 were upregulated after VEGF stimulation and CXCR4 redistributed from the cytoplasm to the cell surface. VEGF was increased by SDF-1 challenge. VEGF, TGFß and SDF-1 stimulation upregulated TGFß(1), TßRI and TßRII in SSc-MSCs. TßRII redistributed from the cytoplasm to focal adhesion contacts. SSc-MSC-conditioned medium showed a greater proangiogenic effect on MVECs than H-MSCs. Experiments with blocking antibodies showed that MSC-derived cytokines were responsible for this potent proangiogenic effect. CONCLUSION: SSc-MSCs constitutively overexpress and release bioactive mediators/proangiogenic factors and potentiate dermal MVEC angiogenesis.

Human mesenchymal stromal cells preserve their stem features better when cultured in the Dulbecco's modified Eagle medium.

BACKGROUND AIMS: The human mesenchymal stromal cell (hMSC), a type of adult stem cell with a fibroblast-like appearance, has the potential to differentiate along the mesenchymal lineage and also along other cell lineages. These abilities make hMSC a promising candidate for use in regenerative medicine. As the hMSC represents a very rare population in vivo, in vitro expansion is necessary for any clinical use. hMSC characterization is commonly carried out through the expression of specific markers and by the capability of differentiating toward at least adipo-, osteo- and chondrocytic lineages. Commitment processes also result in significant changes in the ultrastructure in order to acquire new functional abilities; however, few studies have dealt with the ultrastructural characteristics of hMSC according to the time of incubation and type of media. METHODS: The immunophenotype, functional characteristics and ultrastructural features of bone marrow (BM) hMSC cultured in two different media were investigated. The media chosen were Iscove's modified Dulbecco's medium (IMDM) and the Dulbecco's modified Eagle medium (DMEM). The latter has been recommended recently by two international transplantation and cytotherapy societies, the International Society of Cellular Therapy (ISCT) and European Group for Blood and Bone Marrow Transplantation (EBMT), for hMSC expansion for clinical applications. RESULTS AND CONCLUSIONS: The present results indicate that culture conditions greatly influence hMSC ultrastructural features, proliferation, growth and differentiation. In particular, our findings demonstrate that DMEM preserves the hMSC stem features better. Furthermore, the results obtained in IMDM suggest that a small size does not always correlate with conditions of cell immaturity and a greater proliferative potential.

Autologous mesenchymal stem cells foster revascularization of ischemic limbs in systemic sclerosis: a case report.

BACKGROUND: Mesenchymal stem cells can differentiate into endothelial cells and participate in angiogenesis in adults. In experimental models of acute myocardial infarction, mesenchymal stem cells led to the recovery of cardiac function through the formation of a new vascular network. OBJECTIVE: To describe treatment with intravenous infusions of expanded autologous mesenchymal stem cells in 1 patient with critical limb ischemia due to systemic sclerosis. DESIGN: Case report. SETTING: The rheumatology unit at the University of Florence, Florence, Italy. PATIENT: A woman, aged 34 years, with systemic sclerosis who developed acute gangrene of the upper and lower limbs. INTERVENTION: 3 intravenous pulses of expanded autologous mesenchymal stem cells. MEASUREMENTS: Angiography, skin histopathology, and immunohistochemistry. RESULTS: Areas of necrotic skin were reduced after the first mesenchymal stem-cell infusion. After the third infusion, angiography showed revascularization of the patient's extremities. Skin section analysis revealed cell clusters with tubelike structures, and angiogenic factors were strongly expressed. LIMITATION: Causality cannot be established by a single case. CONCLUSION: In patients with systemic sclerosis who have severe peripheral ischemia, intravenous infusion of expanded autologous mesenchymal stem cells may foster the recovery of the vascular network, restore blood flow, and reduce skin necrosis. PRIMARY FUNDING SOURCE: Fondazione Cassa di Risparmio di Pistoia e Pescia (partial funding).

High recovery of mesenchymal progenitor cells with non-density gradient separation of human bone marrow.

BACKGROUND AIMS: Bone marrow (BM) is the most used source of hemopoietic stem cells (HSC) and mesenchymal stromal cells (MSC) in both hematologic settings and regenerative medicine. We compared the feasibility and reproducibility of two gravity separation techniques, with or without the use of a density gradient, in terms of both hematopoietic and mesenchymal human BM progenitors. METHODS: A total of 16 BM samples was processed to obtain mononuclear cells (MNC) and buffy coats (BC). The efficiency of the two procedures was evaluated by recovery of white blood cells (WBC), MNC and CD34(+) cells, clonogenic assays, red blood cell (RBC) depletion, cell viability, expression of embryonic transcriptional regulators and MSC assessment. RESULTS: The two procedures yielded a comparable recovery of HSC. Non-density gradient separation (NDGS) of BM resulted in four times higher MSC recovery and higher expression of embryonic stem cell markers (Nanog and Sox2) compared with density-gradient separation (DGS). MSC derived from both procedures was comparable in terms of phenotype, differentiation and proliferation potential. CONCLUSIONS: NDGS is less time consuming, provides a better MSC enrichment and appears to be a suitable cell preparation method for clinical applications.

Differences in mesenchymal stem cell cytokine profiles between MS patients and healthy donors: implication for assessment of disease activity and treatment.

MSCs have been proposed as possible treatment in MS: In this study MSCs obtained from 10 MS patients and 6 healthy donors (HD) were compared in terms of phenotypical and functional characteristics. We show that MSCs isolated from MS and HD differ significantly for IP10 production. Therefore, although MSCs isolated from MS patients exhibit the same properties of HD MSCs in terms of proliferation, phenotype, in vitro differentiation, TLR expression, immunosuppressive ability, inhibition of DC differentiation and activation, the use of autologous MSCs in cell therapy of autoimmune diseases should be submitted to attentive evaluation and treatment.