Study Of Mesenchymal Stromal Cells Research Articles

Therapy-Related Myeloid Neoplasm Has a Distinct Pro-Inflammatory Bone Marrow Microenvironment and Delayed DNA Damage Repair

Introduction: Therapy-related myeloid neoplasms (t-MN) are associated with extremely poor clinical outcomes in otherwise long-term cancer survivors. t-MN accounts for ~20% of cases of myeloid neoplasms and is expected to rise due to the increased use of chemotherapy/radiotherapy (CT/RT) and improved cancer survivorship. Historically, t-MN was considered a direct consequence of DNA damage induced in normal hematopoietic stem cells (HSC) by DNA damaging cytotoxics. However, these studies have largely ignored the bone marrow (BM) microenvironment and the effects of age and concurrent/previous cancers. Aim: We performed an exhaustive functional study of mesenchymal stromal cells (MSC) obtained from a comparatively large cohort of t-MN patients and carefully selected control populations to evaluate the long-term damage induced by cytotoxic therapy to BM microenvironment and its impact on malignant and normal haematopoiesis. Methods: Four different cohorts were used: (1) t-MN, in which myeloid malignancy occurred after CT/RT for a previous cancer (n=18); (2) patients with multiple cancer and in which a myeloid neoplasm developed following an independent cancer which was not treated with CT/RT (MC-MN; n=10); (3) primary MN (p-MN; n=7) untreated and without any prior cancer or CT/RT; (4) age-matched controls (HC; n=17). Morphology, proliferation, cellular senescence, differentiation potential and γH2AX DNA damage response was performed. Stem/progenitor supportive capacity was assessed by co-culturing haematopoietic stem cells on MSC feeder-layer in long-term culture initiating assay (LTC-IC). Cytokine measurements were performed using 38-plex magnetic bead panel (Millipore) and RNA sequencing libraries were prepared with Illumina TruSeq Total RNA protocol for 150bp paired-end sequencing on a NextSeq500 instrument. Functional enrichment analysis was performed using EnrichR software. Results: MSC cultured from t-MN patients were significantly different from HC, p-MN and MC-MN MSC according to multiple parameters. They exhibited aberrant morphology consisting of large, rounded and less adhesive cells compared to typical spindle-shaped morphology observed with controls. MSC from myeloid neoplasm also showed impaired proliferation, senescence, osteo- and adipogenic differentiation with t-MN MSC showing the greatest differences. DNA repair was dramatically impaired compared to p-MN and HC (Fig.1A). Importantly, these aberrant t-MN MSC were not able to support normal or autologous in vitro long-term haematopoiesis (Fig.1B). The biological characteristic and poor haematopoietic supportive capacity of MSC could be "cell-intrinsic" or driven by an altered paracrine inflammatory microenvironment. Interestingly, several inflammatory cytokines were higher in t-MN compared with marrow interstitial fluid obtained from p-MN patients (Fig.1Ci) and many of these including Fractalkine, IFNα2, IL-7 and G-CSF were also significantly higher in t-MN MSC conditional media (Fig.1Cii). Together, this data suggest that t-MN microenvironment is distinct from p-MN with paracrine production of pro-inflammatory milieu that may contribute to poor HSC supportive capacity. Preliminary whole transcriptome analysis revealed differential gene expression between t-MN and HC (Fig.1Di) and p-MN MSC. Importantly, the deregulated genes play critical role in cell cycle, DNA damage repair, and cellular senescence pathways explaining phenotypical characteristic of t-MN MSC (Fig.1Dii). Moreover CXCL12 expression, a key regulator of haematopoiesis, was significantly lower in t-MN compared to HC (p=0.002) and p-MN MSC (p=0.009), thus explaining poor HSC supportive capacity. The key difference between the p-MN, MC-MN and t-MN is prior exposure to CT/RT. To study this we obtained MSC from two t-MN patients for whom we had samples at the time of their primary cancer, post high-dose chemotherapy and at the time of t-MN. MSC displayed aberrant proliferation and differentiation capacity after high-dose cytotoxic therapy (2 to 4 years prior to developing t-MN) and remained aberrant at t-MN diagnosis (Fig.1E). Conclusions: BM-MSC from t-MN patients are significantly abnormal compared with age-matched controls and typical myeloid neoplasm. Importantly, prior CT/RT leads to long-term irreversible damage to the BM microenvironment which potentially contributes to t-MN pathogenesis. Disclosures Hughes: Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Hiwase:Novartis Australia: Research Funding.

Secretome studies of mesenchymal stromal cells (MSCs) isolated from three tissue sources reveal subtle differences in potency

Human mesenchymal stromal cells (MSCs) are currently the leading candidate for cell-based therapeutics. While the use of MSCs in transplantation therapies is widely expanding, still, there is a lot of scope for better understanding of the mechanisms underlying their effects. We have generated MSCs from pre- and post-natal human tissue sources such as Wharton's jelly (WJ), stem cells from human exfoliated deciduous teeth (SHED), and bone marrow (BM). We then expanded, banked, and characterized them based on morphology, growth kinetics, senescence, immunophenotype, gene expression, and secretion of growth factors. Although the immunophenotype was very similar across MSCs from the three types of donor tissues, they showed minor variations in their growth kinetics. Further, a higher percentage of senescent cells were observed in BM-MSCs than in WJ-MSCs and SHED. Gene expression analysis showed the increased expression of INF-γ, PDGFA, VEGF, IL10, and SDF in SHED over WJ-MSC and BM-MSC. Comparative secretome profiling by ELISA demonstrated the presence of FGF-2, IL-10, PDGF, SDF-1, Ang-1, TGF-β3, HGF, INF-γ, VEGF, and IL-6 in cell culture supernatants. Based on our findings, WJ-MSC and SHED appear more potent than BM-MSC for managing inflammation, immunomodulation, angiogenesis, fibrosis, and scarring. Due to widespread application of MSCs in cell replacement therapy, these subtle differences need to be taken into consideration while designing stem cell-based clinical trials.

A Scoping Review of Registered Clinical Trials of Cellular Therapy for COVID-19 and a Framework for Accelerated Synthesis of Trial Evidence-FAST Evidence.

The urgent need for safe and effective treatments for COVID-19 has fueled the launch of many parallel complex studies of cellular therapies with small to modest enrolment projections. By pooling data from multiple studies that are similar, we can increase the ability to achieve sufficient power to determine effectiveness more quickly through meta-analysis. A scoping review of registered clinical trials using cell-based interventions for COVID-19 was conducted to identify candidate studies for meta-analysis that could support an accelerated regulatory review. ClinicalTrials.gov and WHO International Clinical Trials Registry Platform were searched April 23, 2020. Trials were included if they utilized cell or cell-derived products to treat or prevent COVID-19. Fifty-four registered cellular therapy trials were identified and included for analysis. Studies of mesenchymal stromal cells (MSCs; 41 studies; 1129 subjects projected to receive cells) and natural killer (NK) cells (5 studies; 135 projected to received cells) were observed most commonly. A subset of studies are controlled (34 studies, or 63%), including 27 studies of MSCs and 3 of NK cells. While heterogeneity in study design exists, the cumulative projected enrolment of patients from similar studies appears sufficient to allow the detection of meaningful differences in clinically important outcomes such as mortality, admission to intensive care and need for mechanical ventilation by September 2020—sooner than any individual study could determine effectiveness. MSCs are the predominant cell type in registered trials for severe or critical COVID-19 and represent the most promising candidates for future meta-analysis. Sufficient pooled sample size to detect clinically important reductions in multiple outcomes, including mortality, is anticipated by September 2020, but may require accessing supplementary data to align outcome reporting. Regulatory approval, funding and implementation by cell manufacturing partners will be accelerated by our framework for rapid meta-analysis.

Update on mesenchymal stromal cell studies in organ transplant recipients.

Mesenchymal stromal cells (MSC) have been proposed as a novel cell therapy for immune-mediated diseases, including solid organ transplantation. Here, we provide an overview of recent preclinical and clinical studies in solid organ transplantation using MSC immunomodulatory therapy. MSC have been tested successfully in models of corneal and lung transplantation, suggesting that either the programmed cell death protein 1/programmed death ligand 1 pathway or the generation of intermediary immune-regulatory monocyte-macrophage population are the main mechanisms of the protolerogenic effect of MSC. In clinical transplantation, allogeneic MSC from bone marrow or umbilical cord have been evaluated in kidney and lung transplantation with an excellent safety profile. Recent data from kidney transplant patients given autologous bone marrow-MSC enrolled in our phase 1 study demonstrated a good long term safety profile. Extensive immunomonitoring of this initial cohort provided evidence of the development of a protolerogenic environment in some MSC-treated patients. One of these patients has been weaned off immunosuppression successfully. The available clinical studies in kidney, liver and lung transplantation indicate that autologous and allogeneic MSC therapy from different sources are safe. Now it's time to focus on well-designed efficacy clinical trials, possibly including extensive immunomonitoring.

131 Phase I/II efficacy and safety study of mesenchymal stromal cells in recessive dystrophic epidermolysis bullosa

131 Phase I/II efficacy and safety study of mesenchymal stromal cells in recessive dystrophic epidermolysis bullosa

Pathogenesis of Acute Respiratory Distress Syndrome.

Acute respiratory distress syndrome (ARDS) is a syndrome of acute respiratory failure caused by noncardiogenic pulmonary edema. Despite five decades of basic and clinical research, there is still no effective pharmacotherapy for this condition and the treatment remains primarily supportive. It is critical to study the molecular and physiologic mechanisms that cause ARDS to improve our understanding of this syndrome and reduce mortality. The goal of this review is to describe our current understanding of the pathogenesis and pathophysiology of ARDS. First, we will describe how pulmonary edema fluid accumulates in ARDS due to lung inflammation and increased alveolar endothelial and epithelial permeabilities. Next, we will review how pulmonary edema fluid is normally cleared in the uninjured lung, and describe how these pathways are disrupted in ARDS. Finally, we will explain how clinical trials and preclinical studies of novel therapeutic agents have further refined our understanding of this condition, highlighting, in particular, the study of mesenchymal stromal cells in the treatment of ARDS.

Acute toxicity study of Mesenchymal Stromal cells derived from Wharton’s Jelly in mouse by intravenous and subcutaneous route

Acute toxicity study of Mesenchymal Stromal cells derived from Wharton’s Jelly in mouse by intravenous and subcutaneous route

In Vivo Effects of Mesenchymal Stromal Cells in Two Patients With Severe Acute Respiratory Distress Syndrome

Mesenchymal stromal cells (MSCs) have been investigated as a treatment for various inflammatory diseases because of their immunomodulatory and reparative properties. However, many basic questions concerning their mechanisms of action after systemic infusion remain unanswered. We performed a detailed analysis of the immunomodulatory properties and proteomic profile of MSCs systemically administered to two patients with severe refractory acute respiratory distress syndrome (ARDS) on a compassionate use basis and attempted to correlate these with in vivo anti-inflammatory actions. Both patients received 2×10(6) cells per kilogram, and each subsequently improved with resolution of respiratory, hemodynamic, and multiorgan failure. In parallel, a decrease was seen in multiple pulmonary and systemic markers of inflammation, including epithelial apoptosis, alveolar-capillary fluid leakage, and proinflammatory cytokines, microRNAs, and chemokines. In vitro studies of the MSCs demonstrated a broad anti-inflammatory capacity, including suppression of T-cell responses and induction of regulatory phenotypes in T cells, monocytes, and neutrophils. Some of these in vitro potency assessments correlated with, and were relevant to, the observed in vivo actions. These experiences highlight both the mechanistic information that can be gained from clinical experience and the value of correlating in vitro potency assessments with clinical effects. The findings also suggest, but do not prove, a beneficial effect of lung protective strategies using adoptively transferred MSCs in ARDS. Appropriate randomized clinical trials are required to further assess any potential clinical efficacy and investigate the effects on in vivo inflammation. This article describes the cases of two patients with severe refractory adult respiratory syndrome (ARDS) who failed to improve after both standard life support measures, including mechanical ventilation, and additional measures, including extracorporeal ventilation (i.e., in a heart-lung machine). Unlike acute forms of ARDS (such in the current NIH-sponsored study of mesenchymal stromal cells in ARDS), recovery does not generally occur in such patients.

The formation of calcium phosphate coatings by pulse laser deposition on the surface of polymeric ferroelectric

This work analyses the properties of calcium phosphate coatings obtained by pulsed laser deposition on the surface of the ferroelectric polymer material. Atomic force and scanning electron microscopy studies demonstrate that, regardless of the type of sputtering target, the calcium phosphate coatings have a multiscale rough surface that is potentially capable of promoting the attachment and proliferation of osteoblasts. This developed surface of the coatings is due to its formation mainly from a liquid phase. The chemical and crystalline composition of the coatings depends on the type of sputtering target used. It was shown that, regardless of the type of sputtering target, the crystalline structure of the ferroelectric polymer material does not change. Cell viability and adhesion studies of mesenchymal stromal cells on the coatings were conducted using flow cytometry and fluorescent microscopy. These studies indicated that the produced coatings are non-toxic.

Effect of growth media and serum replacements on the proliferation and differentiation of adipose-derived stem cells

Studies of mesenchymal stromal cells (MSC) from BM and adipose tissue have demonstrated similar differentiation potentials along the adipo-, osteo- and chondrogenic lineages. While most clinical trials have been performed using BM-derived MSC, the focus is shifting toward the use of stem cells derived from fat tissue. The aim of the current investigation was to define optimal culture conditions that would facilitate clinical use of adipose-derived stem cells (ASC). Different types and concentrations of serum replacers and basal media were tested with respect to the optimal expansion and subsequent differentiation of primary human ASC. The effect of initial seeding density on the growth of ASC was also determined. While several of the serum replacements proved to be clearly inferior to fetal calf serum (FCS) in promoting ASC growth, the knockout serum replacement (KOSR) had expansion properties similar to those of FCS. However, with respect to the capacity to support adipo-, osteo- and chondrogenic differentiation, KOSR proved to be less consistent than FCS. Among the media formulations, modified Eagle medium alpha supported a significantly faster cell expansion than the other basal media while still maintaining the full differentiation potential of ASC. Regarding the plating density most favorable for rapid expansion, we found that initial plating densities ranging from 100 to 200 cell/cm(2) resulted in significantly shorter doubling times than plating densities both below and above that range. Identification of the optimal basal medium and serum replacer, together with the most favorable plating density, will facilitate cell-based and tissue-engineering applications employing ASC in pre-clinical and clinical settings.