Optimization of Mesenchymal Stromal Cell (MSC) Manufacturing Processes for a Better Therapeutic Outcome.

MSCs products as well as their derived extracellular vesicles, are currently being explored as advanced biologics in cell-based therapies with high expectations for their clinical use in the next few years. In recent years, various strategies designed for improving the therapeutic potential of mesenchymal stromal cells (MSCs), including pre-conditioning for enhanced cytokine production, improved cell homing and strengthening of immunomodulatory properties, have been developed but the manufacture and handling of these cells for their use as advanced therapy medicinal products (ATMPs) remains insufficiently studied, and available data are mainly related to non-industrial processes. In the present article, we will review this topic, analyzing current information on the specific regulations, the selection of living donors as well as MSCs from different sources (bone marrow, adipose tissue, umbilical cord, etc.), in-process quality controls for ensuring cell efficiency and safety during all stages of the manual and automatic (bioreactors) manufacturing process, including cryopreservation, the use of cell banks, handling medicines, transport systems of ATMPs, among other related aspects, according to European and US legislation. Our aim is to provide a guide for a better, homogeneous manufacturing of therapeutic cellular products with special reference to MSCs.

Efficacy and safety of intramuscular administration of allogeneic adipose tissue derived and expanded mesenchymal stromal cells in diabetic patients with critical limb ischemia with no possibility of revascularization: study protocol for a randomized controlled double-blind phase II clinical trial (The NOMA Trial).

BACKGROUND: Chronic lower limb ischemia develops earlier and more frequently in patients with type 2 diabetes mellitus. Diabetes remains the main cause of lower-extremity non-traumatic amputations. Current medical treatment, based on antiplatelet therapy and statins, has demonstrated deficient improvement of the disease. In recent years, research has shown that it is possible to improve tissue perfusion through therapeutic angiogenesis. Both in animal models and humans, it has been shown that cell therapy can induce therapeutic angiogenesis, making mesenchymal stromal cell-based therapy one of the most promising therapeutic alternatives. The aim of this study is to evaluate the feasibility, safety, and efficacy of cell therapy based on mesenchymal stromal cells derived from adipose tissue intramuscular administration to patients with type 2 diabetes mellitus with critical limb ischemia and without possibility of revascularization. METHODS: A multicenter, randomized double-blind, placebo-controlled trial has been designed. Ninety eligible patients will be randomly assigned at a ratio 1:1:1 to one of the following: control group (n = 30), low-cell dose treatment group (n = 30), and high-cell dose treatment group (n = 30). Treatment will be administered in a single-dose way and patients will be followed for 12 months. Primary outcome (safety) will be evaluated by measuring the rate of adverse events within the study period. Secondary outcomes (efficacy) will be measured by assessing clinical, analytical, and imaging-test parameters. Tertiary outcome (quality of life) will be evaluated with SF-12 and VascuQol-6 scales. DISCUSSION: Chronic lower limb ischemia has limited therapeutic options and constitutes a public health problem in both developed and underdeveloped countries. Given that the current treatment is not established in daily clinical practice, it is essential to provide evidence-based data that allow taking a step forward in its clinical development. Also, the multidisciplinary coordination exercise needed to develop this clinical trial protocol will undoubtfully be useful to conduct academic clinical trials in the field of cell therapy in the near future. TRIAL REGISTRATION: ClinicalTrials.gov NCT04466007 . Registered on January 07, 2020. All items from the World Health Organization Trial Registration Data Set are included within the body of the protocol.

Use of cryopreserved human amniotic membrane in the treatment of skin ulcers secondary to calciphylaxis.

Calciphylaxis is a rare condition characterized by skin ulceration and necrosis as a result of vascular calcification of the small and medium blood vessels of skin and subcutaneous tissues. It mainly occurs in patients with advanced chronic kidney disease and sometimes leads to complications with a fatal outcome. In this report, we describe the case of a 67-year-old male patient with end stage renal disease presenting painful skin ulcers on his lower limbs. The lesions had progressively grown and were associated to severe pain and decreased quality of life. The ulcers did not respond to conventional treatments and the patient underwent skin biopsy of these lesions obtaining anatomopathological findings compatible with calciphylaxis. In this report, we present an innovative treatment for skin ulcers secondary to calciphylaxis using cryopreserved amniotic membrane (AM) as a dressing in order to promote epithelialization of the wounds. After four applications, healing of the main ulcer and reduction in pain was achieved. In summary, applying cryopreserved AM probed to be a promising strategy to reduce pain and to enhance epithelialization and healing of chronic non-responsive ulcers in calciphylaxis.

Production via good manufacturing practice of exofucosylated human mesenchymal stromal cells for clinical applications.

BACKGROUND: The regenerative and immunomodulatory properties of human mesenchymal stromal cells (hMSCs) have raised great hope for their use in cell therapy. However, when intravenously infused, hMSCs fail to reach sites of tissue injury. Fucose addition in α(1,3)-linkage to terminal sialyllactosamines on CD44 creates the molecule known as hematopoietic cell E-/L-selectin ligand (HCELL), programming hMSC binding to E-selectin that is expressed on microvascular endothelial cells of bone marrow (BM), skin and at all sites of inflammation. Here we describe how this modification on BM-derived hMSCs (BM-hMSCs) can be adapted to good manufacturing practice (GMP) standards. METHODS: BM-hMSCs were expanded using xenogenic-free media and exofucosylated using α(1,3)-fucosyltransferases VI (FTVI) or VII (FTVII). Enforced fucosylation converted CD44 into HCELL, and HCELL formation was assessed using Western blot, flow cytometry and cell-binding assays. Untreated (unfucosylated), buffer-treated and exofucosylated BM-hMSCs were each analyzed for cell viability, immunophenotype and differentiation potential, and E-selectin binding stability was assessed at room temperature, at 4°C, and after cryopreservation. Cell product safety was evaluated using microbiological testing, karyotype analysis, and c-Myc messenger RNA (mRNA) expression, and potential effects on genetic reprogramming and in cell signaling were analyzed using gene expression microarrays and receptor tyrosine kinase (RTK) phosphorylation arrays. RESULTS: Our protocol efficiently generates HCELL on clinical-scale batches of BM-hMSCs. Exofucosylation yields stable HCELL expression for 48 h at 4°C, with retained expression after cell cryopreservation. Cell viability and identity are unaffected by exofucosylation, without changes in gene expression or RTK phosphorylation. DISCUSSION: The described exofucosylation protocol using xenogenic-free reagents enforces HCELL expression on hMSCs endowing potent E-selectin binding without affecting cell viability or native phenotype. This described protocol is readily scalable for GMP-compliant clinical production.

[Bacteraemia due to Escherichia coli producing extended-spectrum beta-lactamases (ESBL): clinical relevance and today's insights]. / Bacteriemias por Escherichia coli productor de betalactamasas de espectro extendido (BLEE): significación clínica y perspectivas actuales.

Antibiotic resistance is an old problem with new face as the rate of infections due to multidrug resistant bacteria is higher everyday and the number of new antibiotics to overwhelm the problem is becoming smaller. E. coli is the most frequent agent causing nosocomial or community-acquired bacteraemia being in our country 10% of them extended-spectrum beta-lactamases (ESBL) producing E. coli isolates. Nowadays the number of community- acquired or health-related infections caused by these ESBL producing E. coli is increasing. CTX-M has also become the most frequent ESBL compared to other enzymes. The role of these enzymes as a virulence factor increasing mortality in patients with bacteraemia due to E. coli is not well defined. The relevance of ESBL-E. coli seems to be related with the higher frequency of inadequate treatment and therefore the importance of identifying factors or features that might predict that the patient's infection is due to one of these isolates. In terms of prevention and control of infection measures, the role of patient's isolation is not clear but a proper prescription of antibiotics and antibiotic control policies are probably important to reduce the problem.

Large-volume-apheresis facilitates autologous transplantation of hematopoietic progenitors in poor mobilizer patients.

Given that pre-apheresis CD34(+) cell count (PA-CD34) predicts the apheresis' yield, a minimum of 5 to 20 PA-CD34/microl is required in many institutions to initiate cell collection. The aim of this study was to clarify whether large-volume-apheresis (LVA) could facilitate progenitor cell transplantation in patients with low PA-CD34. Apheresis was initiated in 226 patients, disregarding PA-CD34, at days: +5 in G-CSF, +10 in cyclophosphamide+G-CSF, and +15 to +20 in other chemotherapy+G-CSF mobilization, when leucocytes >2.5 x 10(9)/L. Four times the blood volume was processed. Patients were grouped according to their PA-CD34: >or=10/microl (group-A, n = 143); <10/microl but >or=5/microl (group-B, n = 40) and <5/microl (group-C, n = 43). No differences were found in diagnoses, gender, age, previous treatments or mobilization regimen between groups. Enough CD34(+) cells (>1.9 x 10(6)/kg) were obtained in 31 patients (72%) from group-C, although in this group two mobilizations were needed in 20 patients (46.5%), compared to 5 (3.5%) and 1 (2.5%) in groups A and B, respectively (P < 0.01). Evenly three apheresis or more were required in 28 patients (65.1%) from group-C, compared to 8 (5.6%) and 6 (15.0%) in groups A and B, respectively (P < 0.01). In conclusion LVA can facilitate autologous transplantation in poor-mobilizer-patients, low PA-CD34 should not be an inflexible exclusion factor.