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In the Emilia-Romagna region of Italy, a unique Hub and Spoke model was adopted to recognize BRCA -related breast cancer (BC) patients. Characteristics and outcomes of tumors identified by this model will be presented. This multicenter retrospective cohort study involved patients diagnosed with BRCA -related BC identified in the Emilia-Romagna region between January 2000 and December 2013. Seven provinces collected data on patient and tumor characteristics; clinical and gene testing information were also registered. Comparisons between BRCA1 and BRCA2 BC were performed. To balance different variants to identify significant predictors of survival, an inverse probability of treatment weighting (IPTW) analysis on Cox regression was conducted. From 2000 to 2013, 284 BRCA -related BC were registered (171 BRCA1 , 110 BRCA2 , and 3 BRCA1 and BRCA2). BRCA1 were diagnosed at an earlier stage compared to BRCA2 (50.1 % vs 30 %, respectively, in stage I, P = 0.0015). BRCA2 patients underwent more up-front surgery (85 % vs. 74.9 %, P = 0.049) and less chemotherapy (69.1 % vs 88.9 %, P = 0.004) than BRCA1 patients. At 11.8 years median follow-up, BRCA1 patients developed more second contralateral BC (P = 0.09), while BRCA2 had more visceral relapses (P = 0.013). No differences in overall survival (OS) between BRCA1 and BRCA2 patients (P = 0.07) were found. An advantage in OS was independently seen for patients who underwent contralateral prophylactic mastectomy (P = 0.0001) and oophorectomy (P < 0.0001). In conclusion, adopting a homogeneous regional framework provides important information about prevention and treatment strategies of BRCA -related BC and suggests using maximal surgery to improve OS. [ABSTRACT FROM AUTHOR]

[Display omitted] • Endometrial cancer includes different histopathological subtypes and an increasing number of emerging molecular characterizations. • 5–10% of Endometrial cancers are hereditary, most of which occur within hereditary non-polyposis colorectal cancer syndrome or Lynch syndrome. • Endometrial cancer risk stratification and treatment selection are currently based on both histopathological and molecular criteria. • Prospective studies accounting for somatic and germline alterations of endometrial cancer are ongoing to optimize clinical management. Endometrial cancer (EC) incidence and mortality rates have been increasing, particularly among young females. Although more than 90% of ECs are sporadic, 5–10% are hereditary, a majority of which occurs within Hereditary Non-Polyposis Colorectal Cancer syndrome (HNPCC) or Lynch syndrome. The traditional histopathological classification differentiates EC between two main groups: type I (or endometrioid) and type II (including all other histopathological subtypes). However, this classification lacks reproducibility and does not account for the emerging molecular heterogeneity. In 2013, The Cancer Genome Atlas (TCGA) project proposed EC molecular classification defining four groups with different prognostic and predictive values and the current international guidelines are progressively establishing EC risk stratification and treatment based on both histopathological and molecular criteria. Our manuscript aims to summarize the current state of EC molecular characterizations, including germline alterations at the basis of hereditary EC predisposition, to discuss their clinical utility as prognostic and predictive markers. [ABSTRACT FROM AUTHOR]

The World Health Organization (WHO) assigns International Nonproprietary Names (INN) to pharmaceutical substances, including advanced therapy medicinal products, to ensure that each substance is globally recognized by a unique name. The majority of INN are published in the WHO Drug Information in accordance with the nomenclature rules of the International Union of Pure and Applied Chemistry. However, advanced therapy medicinal products, and in particular cell therapy and cell-based gene therapy substances, cannot be defined by such chemical nomenclature. Instead, they are published together with a textual definition paragraph to unambiguously describe their characteristics. These definitions are an integral part of the INN nomenclature system, and their presence contributes to pharmacovigilance and patient safety, as they help to distinguish regulated substances from cell-based interventions that have no INN and are marketed without regulatory oversight. Particular attention is therefore allocated to these descriptive paragraphs, as they form the basis for defining the uniqueness of a particular cell substance. This review describes the INN nomenclature system for cell-based substances and focuses on the progress made by the WHO INN Programme to develop and harmonize these definition paragraphs, which is reflected in a newly revised INN application form for cell therapy substances. [ABSTRACT FROM AUTHOR]

Abstract The Signature Series Symposium "Cellular Therapies for Orthopaedics and Musculoskeletal Disease Proven and Unproven Therapies—Promise, Facts and Fantasy" was held as a pre-meeting of the 26th International Society for Cellular Therapy (ISCT) annual congress in Montreal, Canada, May 2, 2018. This was the first ISCT program that was entirely dedicated to the advancement of cell-based therapies for musculoskeletal diseases. Cellular therapies in musculoskeletal medicine are a source of great promise and opportunity. They are also the source of public controversy, confusion and misinformation. Patients, clinicians, scientists, industry and government share a commitment to clear communication and responsible development of the field. Therefore, this symposium convened thought leaders from around the world in a forum designed to catalyze communication and collaboration to bring the greatest possible innovation and value to patients with musculoskeletal conditions. [ABSTRACT FROM AUTHOR]

The article discusses views of the 2015 International Society for Cellular Therapy (ISCT) on the issue of unproven cellular therapies for patients, which are not recognized on medical grounds.

Background aims. Mesenchymal stromal/stem cells (MSCs) can be isolated from human bone marrow (BM), expanded ex vivo and identified via numerous surface antigens. Despite the importance of these cells in regenerative therapy programs, it is unclear whether the cell membrane signature defining MSC preparations ex vivo is determined during culture or may reflect an in vivo counterpart. BM-MSC phenotype in vivo requires further investigation. Methods. To characterize cells in their natural BM environment, we performed multi-parametric immunohistochemistry on trabecular bone biopsy specimens from multiple donors and described cells by different morphology and micro-anatomic localization in relationship to a precise pattern of MSC antigen expression. Results. Microscopically examined high-power field marrow sections revealed an overlapping in vivo expression of antigens characterizing ex vivo expanded BM-MSCs, including CD 10, CD73, CD 140b, CD 146, GD2 and CD27 1. Expanding this panel to proteins associated with pluripotency, such as Oct4, Nanog and SSEA-4, we were able to identify different cellular populations in the human trabecular bone and BM expressing different progenitor cell markers. Conclusions. Targeting several multipotency and pluripotency markers, we found that the BM contains iden- tifiable and distinct progenitor cells further justifying their introduction for a wide range of applications in regenerative medicine. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the author discusses various reports within the issue on topics including the concept of unproven cellular therapy, parameters in cell manufacturing, and the regulatory landscape for cell-based product manufacturing.

Mesenchymal stromal cells (MSCs) are polymorphic, adherent cells with the capability to stimulate tissue regeneration and modulate immunity. MSCs have been broadly investigated for potential therapeutic applications, particularly immunomodulatory properties, wound healing and tissue regeneration. The exact physiologic role of MSCs, however, remains poorly understood, and this gap in knowledge significantly impedes the rational development of therapeutic cells. Here, we considered interferon γ (IFN-γ) and tumor necrosis factor alpha (TNF-α), two cytokines likely encountered physiologically and commonly used in cell manufacturing. For comparison, we studied interleukin-10 (IL-10) (anti-inflammatory) and interleukin-4 (IL-4) (type 2 cytokine). We directly assessed the effects of these cytokines on bone marrow MSCs by comparing RNA Seq transcriptional profiles. Western blotting and flow cytometry were also used to evaluate effects of cytokine priming. The type 1 cytokines (IFN-γ and TNF-α) induced striking changes in gene expression and remarkably different profiles from one another. Importantly, priming MSCs with either of these cytokines did not increase variability among multiple donors beyond what is intrinsic to non-primed MSCs from different donors. IFN-γ–primed MSCs expressed IDO1 and chemokines that recruit activated T cells. In contrast, TNF-α–primed MSCs expressed genes in alternate pathways, namely PGE2 and matrix metalloproteinases synthesis, and chemokines that recruit neutrophils. IL-10 and IL-4 priming had little to no effect. Our data suggest that IFN-γ–primed MSCs may be a more efficacious immunosuppressive therapy aimed at diseases that target T cells (ie, graft-versus-host disease) compared with TNF-α–primed or non-primed MSCs, which may be better suited for therapies in other disease settings. These results contribute to our understanding of MSC bioactivity and suggest rational ex vivo cytokine priming approaches for MSC manufacturing and therapeutic applications. [ABSTRACT FROM AUTHOR]

Stem cells have important clinical and experimental potentials. Trophoblast stem (TS) cells possess the ability to differentiate into trophoblast subtypes in vitro and contribute to the trophoblast lineage in vivo. Suppressor of cytokine signaling 3 (50C53) is a negative regulator of cytokine signaling. Targeted disruption of SOCS3 revealed embryonic lethality on E12.5; it was caused by placental defect with enhanced leukemia inhibitory factor receptor signaling. A complementation of the wild-type (WT) placenta by using tetraploid rescue technique showed that the embryonic lethality in SOCS3-deficient embryo was due to the placental defect. Here we demonstrate that TS cells supplementation rescues placental defect in SOCS3-deficient embryos. In the rescued placenta, TS cells were integrated into the placental structure, and a substantial structural improvement was observed in the labyrinthine layer that was disrupted in the SOCS3-deficient placenta. Importantly, by supplying TS cells, living SOCS3-deficient embryos were detected at term. These results indicate a functional contribution of TS cells in the placenta and their potential application. [ABSTRACT FROM AUTHOR]

The proapoptotic protein tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is physiologically expressed by immune cells and performs regulatory functions in infections, autoimmune diseases and cancer, where it acts as a tumor suppressor. Adipose-derived mesenchymal stromal cells (AD-MSCs) also may play immunomodulatory roles in both primary and acquired immune responses. We have previously demonstrated the efficacy of an anticancer gene therapy based on AD-MSC engineered to secrete a soluble TRAIL variant (sTRAIL) against pancreatic cancer. However, the impact of AD-MSC sTRAIL on leukocyte subsets has been not yet considered also to predict a possible immunotoxicity profile in the clinical translation of this cell-based anticancer strategy. Monocytes, polymorphonuclear cells and T lymphocytes were freshly isolated from the peripheral blood of healthy donors. Immunophenotype and functional (DR4 and DR5) and decoy (DcR1 and DcR2) TRAIL receptors were tested by flow cytometry. The viability of white blood cells treated with sTRAIL released by gene-modified AD-MSC or co-cultured with AD-MSC sTRAIL was then evaluated by both metabolic assays and flow cytometry. In addition, cytokine profile in co-cultures was analyzed by multiplex enzyme-linked immunosorbent assay. Monocytes and polymorphonuclear cells showed high positivity for DR5 and DcR2, respectively, whereas T cells revealed negligible expression of all TRAIL receptors. Irrespective of TRAIL receptors' presence on the cell membrane, white blood cells were refractory to the proapoptotic effect displayed by sTRAIL secreted by gene-modified AD-MSC, and direct cell-to-cell contact with AD-MSC sTRAIL had negligible impact on T-cell and monocyte viability. Cytokine crosstalk involving interleukin 10, tumor necrosis factor alpha, and interferon gamma secreted by T lymphocytes and vascular endothelial growth factor A and interleukin 6 released by AD-MSC was highlighted in T-cell and AD-MSC sTRAIL co-cultures. In summary, this study demonstrates the immunological safety and thus the clinical feasibility of an anticancer approach based on AD-MSC expressing the proapoptotic molecule sTRAIL. [ABSTRACT FROM AUTHOR]

The article discusses the commercialization of unproven cell therapies and cell-based products which depends on regulation in pre- and post-marketing phases of product development.

Mesenchymal stromal/stem cells (MSCs) have been widely tested against many diseases, with more than 1000 registered clinical trials worldwide. Despite many setbacks, MSCs have been approved for the treatment of graft-versus-host disease and Crohn disease. However, it is increasingly clear that MSCs exert their therapeutic functions in a paracrine manner through the secretion of small extracellular vesicles (sEVs) of 50–200 nm in diameter. Unlike living cells that can persist long-term, sEVs are non-living and non-replicative and have a transient presence in the body. Their small size also renders sEV preparations highly amenable to sterilization by filtration. Together, acellular MSC-sEV preparations are potentially safer and easier to translate into the clinic than cellular MSC products. Nevertheless, there are inherent challenges in the development of MSC-sEV drug products. MSC-sEVs are products of living cells, and living cells are sensitive to changes in the external microenvironment. Consequently, quality control metrics to measure key identity and potency features of MSC-sEV preparations have to be specified during development of MSC-sEV therapeutics. The authors have previously described quantifiable assays to define the identity of MSC-sEVs. Here the authors discuss requirements for prospective potency assays to predict the therapeutic effectiveness of the drug substance in accordance with International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. Although potency assays should ideally reflect the mechanism of action (MoA), this is challenging because the MoA for the reported efficacy of MSC-sEV preparations against multiple diseases of diverse underlying pathology is likely to be complex and different for each disease and difficult to fully elucidate. Nevertheless, robust potency assays could be developed by identifying the EV attribute most relevant to the intended biological activity in EV-mediated therapy and quantifying the EV attribute. Specifically, the authors highlight challenges and mitigation measures to enhance the manufacture of consistent and reproducibly potent sEV preparations, to identify and select the appropriate EV attribute for potency assays despite a complex "work-in-progress" MoA and to develop assays likely to be compliant with regulatory guidance for assay validation. [Display omitted] [ABSTRACT FROM AUTHOR]

Mesenchymal stromal cells (MSCs) possess remarkable tumor tropism, making them ideal vehicles to deliver tumor-targeted therapeutic agents; however, their value in clinical medicine has yet to be realized. A barrier to clinical utilization is that only a small fraction of infused MSCs ultimately localize to the tumor. In an effort to overcome this obstacle, we sought to enhance MSC trafficking by focusing on the factors that govern MSC arrival within the tumor microenvironment. Our findings show that MSC chemoattraction is only present in select tumors, including osteosarcoma, and that the chemotactic potency among similar tumors varies substantially. Using an osteosarcoma xenograft model, we show that human MSCs traffic to the tumor within several hours of infusion. After arrival, MSCs are observed to localize in clusters near blood vessels and MSC-associated bioluminescence signal intensity is increased, suggesting that the seeded cells expand after engraftment. However, our studies reveal that a significant portion of MSCs are eliminated en route by splenic macrophage phagocytosis, effectively limiting the number of cells available for tumor engraftment. To increase MSC survival, we transiently depleted macrophages with liposomal clodronate, which resulted in increased tumor localization without substantial reduction in tumor-associated macrophages. Our data suggest that transient macrophage depletion will significantly increase the number of MSCs in the spleen and thus improve MSC localization within a tumor, theoretically increasing the effective dose of an anti-cancer agent. This strategy may subsequently improve the clinical efficacy of MSCs as vehicles for the tumor-directed delivery of therapeutic agents. [ABSTRACT FROM AUTHOR]

• In a cohort of patients with locally advanced Non-Small Cell Lung Cancer and associated Central Airways Obstruction interventional bronchoscopy as a part of an integrated treatment improved 1-year survival. • Interventional bronchoscopy reduced new hospitalizations, increased symptom-free interval and prevented atelectasis. • Genetic and anatomic phenotyping might identify patients who may gain life expectancy from the endoscopic intervention. Despite new therapeutic perspectives, the presence of central airways occlusion (CAO) in patients with locally advanced non-small cell lung cancer (NSCLC) is associated with poor survival. There is no clear evidence on the clinical impact of interventional bronchoscopy as a part of an integrated treatment to cure these patients. This retrospective cohort study was conducted in two teaching hospitals over a 10 years period (January 2010-January 2020) comparing patients with NSCLC at stage IIIB and CAO at disease onset treated with chemotherapy/radiotherapy (standard therapy-ST) with those receiving interventional bronchoscopy plus ST (integrated treatment-IT). Primary outcome was 1-year survival. The onset of respiratory events, symptoms-free interval, hospitalization, need for palliation, and overall mortality served as secondary outcomes. A total of 100 patients were included, 60 in the IT and 40 in the ST group. Unadjusted Kaplan-Meier estimates showed greater effect of IT compared to ST on 1-year survival (HR = 2.1 95%CI[1.1-4.8], p = 0.003). IT showed a significantly higher survival gain over ST in those patients showing KRAS mutation (7.6 VS 0.8 months,<0.0001), a lumen occlusion >65% (6.6 VS 2.9 months,<0.001), and lacking the involvement of left bronchus (7 VS 2.3 months,<0.0001). Compared to ST, IT also showed a favorable difference in terms of new hospitalizations (p = 0.03), symptom-free interval (p = 0.02), and onset of atelectasis (p = 0.01). In patients with NSCLC stage IIIB and CAO, additional interventional bronchoscopy might impact on 1-year survival. Genetic and anatomic phenotyping might allow identifying those patients who may gain life expectancy from the endoscopic intervention. [ABSTRACT FROM AUTHOR]

STATEMENT: The International Society for Cellular and Gene Therapies (ISCT) and the International Society for Extracellular Vesicles (ISEV) recognize the potential of extracellular vesicles (EVs, including exosomes) from mesenchymal stromal cells (MSCs) and possibly other cell sources as treatments for COVID-19. Research and trials in this area are encouraged. However, ISEV and ISCT do not currently endorse the use of EVs or exosomes for any purpose in COVID-19, including but not limited to reducing cytokine storm, exerting regenerative effects or delivering drugs, pending the generation of appropriate manufacturing and quality control provisions, pre-clinical safety and efficacy data, rational clinical trial design and proper regulatory oversight. [ABSTRACT FROM AUTHOR]

At the end of January 2020, a novel betacoronavirus, known as severe acute respiratory syndrome coronavirus 2, progressively spread in Italy. Patients with cancer are considered more prone to infections because of the immunosuppressive status due to both malignancy and anticancer treatments. From the first Italian government restrictions (23rd February), Modena Cancer Center adopted practical health vigilance recommendations to minimise the risk of exposure to the virus without overlooking cancer management. From 23rd February to 31st March 2020, 1257 patients on active anticancer treatment for oncological or haematological malignancies attended our institution. All the staff activities were rescheduled following our practical coronavirus disease 2019 (COVID-19) guideline. During this period, we have tallied 9 cases of COVID-19 infection (0.71%) in patients with cancer and 3 cases (1.66%) in health workers. The mortality rate of our patients with cancer was 22%, consistent with the data reported in the literature. In conclusion, following our practical health vigilance recommendations, physicians should be confident in maintaining life-saving anticancer treatment without exceedingly increasing the risk of nosocomial COVID-19 infection. The high rate of mortality suggested that all patients on active anticancer treatment with flu-like symptoms have to be carefully screened for COVID-19 infection. • Owing to the coronavirus disease 2019 (COVID-19) spread, Modena Cancer Center adopted some health recommendations. • Of the patients with cancer on active treatment, 0.71% had COVID-19 infection. • Of the Modena Cancer Center health workers, 1.66% experienced COVID-19 infection. • We propose to apply our health vigilance recommendations in all cancer centres. [ABSTRACT FROM AUTHOR]

Abstract Objectives Mesenchymal stromal/stem cells have immunosuppressive functions. Our previous results demonstrated that one of the players of this immunomodulation can be ascribed to the Human Leukocyte Antigen-G. HLA-G, a non classical HLA class I antigen, is involved in immune tolerance during pregnancy, organ transplantation, autoimmune and inflammatory diseases. In this study we wanted to verify whether human endometrial decidual tissue derived (EDT)-MSC could express HLA-G. Additionally we assessed the permissivity to Human Herpesvirus infections, using HSV-1 as a model, and the possible effect on EDT-MSC immunosuppressive functions towards peripheral blood mononuclear cell (PBMC) proliferation. Methods We analyzed immune-inhibitory functions and HLA-G expression in human EDT-MSC before and after HSV-1 infection. Results We observed that EDT-MSC express HLA-G molecules, that partly are responsible for the immune-inhibitory functions of EDT-MSC towards PBMC proliferation. EDT-MSC are permissive for a productive infection by HSV-1, that decreases HLA-G expression and affects EDT-MSC immune-inhibitory functions. Conclusions We demonstrate that EDT-MSC are susceptible to HSV-1 infection, that reduces HLA-G expression and their immune-inhibitory function. These data could have a clinical implication in the use of EDT-MSC as an immunosuppressant, in particular in steroid-refractory GvHD after allogeneic hematopoietic stem cell transplantation and in autoimmune diseases. [ABSTRACT FROM AUTHOR]

Abstract Cell and gene therapies (CGTs) are progressively entering into clinical practice in different parts of the world. The International Society for Cell & Gene Therapy (ISCT), a global scientific society, has been committed since 1992 to supporting and developing knowledge on clinical applications of CGTs. Considering the number of products that have been progressively approved and, in some cases, withdrawn in recent years, the ISCT would like to present a brief annual report on CGTs with marketing authorization (MA) in different regions. This article reflects the dynamic momentum around authorized CGTs coinciding with the parallel increase of unproven approaches where cells are delivered without appropriate and rigorous scientific and regulatory assessment and authorization. This is intended to be a living document with a yearly update linked to a dedicated section of the ISCT website for faster adjustments. The aim is to ultimately inform, by periodic snapshots, the scientific community, healthcare stakeholders and patient associations on authorized CGT products as a way to increase communication around the approved therapeutic approaches charged with heightened expectations. [ABSTRACT FROM AUTHOR]

Fibrosis is shared in multiple diseases with progressive tissue stiffening, organ failure and limited therapeutic options. This unmet need is also due to the lack of adequate pre-clinical models to mimic fibrosis and to be challenged novel by anti-fibrotic therapeutic venues. Here using bioprinting, we designed a novel 3D model where normal human healthy fibroblasts have been encapsulated in type I collagen. After stimulation by Transforming Growth factor beta (TGFβ), embedded cells differentiated into myofibroblasts and enhanced the contractile activity, as confirmed by the high level of α − smooth muscle actin (αSMA) and F-actin expression. As functional assays, SEM analysis revealed that after TGFβ stimulus the 3D microarchitecture of the scaffold was dramatically remolded with an increased fibronectin deposition with an abnormal collagen fibrillar pattern. Picrius Sirius Red staining additionally revealed that TGFβ stimulation enhanced of two logarithm the collagen fibrils neoformation in comparison with control. These data indicate that by bioprinting technology, it is possible to generate a reproducible and functional 3D platform to mimic fibrosis as key tool for drug discovery and impacting on animal experimentation and reducing costs and time in addressing fibrosis. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Background Osteosarcoma (OS) is the most frequent pediatric malignant bone tumor. OS patients have not seen any major therapeutic progress in the last 30 years, in particular in the case of metastatic disease, which requires new therapeutic strategies. The pro-apoptotic cytokine Tumor necrosis factor (TNF)–Related Apoptosis Inducing Ligand (TRAIL) can selectively kill tumor cells while sparing normal cells, making it a promising therapeutic tool in several types of cancer. However, many OS cell lines appear resistant to recombinant human (rh)TRAIL-induced apoptosis. We, therefore, hypothesized that TRAIL presentation at the membrane level of carrier cells might overcome this resistance and trigger apoptosis. Methods To address this, human adipose mesenchymal stromal cells (MSCs) transfected in a stable manner to express membrane-bound full-length human TRAIL (mbTRAIL) were co-cultured with several human OS cell lines. Results This induced apoptosis by cell-to-cell contact even in cell lines initially resistant to rhTRAIL. In contrast, mbTRAIL delivered by MSCs was not able to counteract tumor progression in this OS orthotopic model. Discussion This was partly due to the fact that MSCs showed a potential to support tumor development. Moreover, the expression of mbTRAIL did not show caspase activation in adjacent tumor cells. [ABSTRACT FROM AUTHOR]

Background aims Numerous cellular models have been developed to investigate calcification for regenerative medicine applications and for the identification of therapeutic targets in various complications associated with age-related diseases. However, results have often been contradictory due to specific culture conditions, cell type ontogeny and aging status. Human platelet lysate (hPL) has been recently investigated as valuable alternative to fetal bovine serum (FBS) in cell culture and bone regeneration. A parallel comparison of how all these multiple factors may converge to influence mineralization has yet to be reported. Methods To compare mineralization of human mesenchymal cell types known to differ in extracellular matrix calcification potency, bone marrow–derived mesenchymal stromal cells and dermal fibroblasts from neonatal and adult donors, at both low and high passages, were investigated in an ex vivo experimental model by supplementing the osteogenic induction medium with FBS or with hPL. Four commercial hPL preparations were profiled by liquid chromatography/electrospray ionization quadrupole time-of-flight spectrometry, and mineralization was visualized by von Kossa staining and quantified by morphometric evaluations after 9, 14 and 21 days of culture. Results Data demonstrate that (i) commercial hPL preparations differ according to mass spectra profiles, (ii) hPL variously influences mineral deposition depending on cell line and possibly on platelet product preparation methods, (iii) donor age modifies mineral deposition in the presence of the same hPL and (iv) reduced in vitro proliferative capacity affects osteogenic induction and response to hPL. Conclusion Despite the standardized procedures applied to obtain commercial hPL, this study highlights the divergent effects of different preparations and emphasizes the importance of cellular ontology, donor age and cell proliferative capacity to optimize the osteogenic induction capabilities of mesenchymal stromal cells and design more effective cell-based therapeutic protocols. [ABSTRACT FROM AUTHOR]

Background Systemic infusion of mesenchymal stromal cells (MSCs) has been shown to induce acute acceleration of growth velocity in children with osteogenesis imperfecta (OI) despite minimal engraftment of infused MSCs in bones. Using an animal model of OI we have previously shown that MSC infusion stimulates chondrocyte proliferation in the growth plate and that this enhanced proliferation is also observed with infusion of MSC conditioned medium in lieu of MSCs, suggesting that bone growth is due to trophic effects of MSCs. Here we sought to identify the trophic factor secreted by MSCs that mediates this therapeutic activity. Methods To examine whether extracellular vesicles (EVs) released from MSCs have therapeutic activity, EVs were isolated from MSC conditioned medium by ultracentrifugation. To further characterize the trophic factor, RNA or microRNA (miRNA) within EVs was depleted by either ribonuclease (RNase) treatment or suppressing miRNA biogenesis in MSCs. The functional activity of these modified EVs was evaluated using an in vitro chondrocyte proliferation assay. Finally, bone growth was evaluated in an animal model of OI treated with EVs. Results We found that infusion of MSC-derived EVs stimulated chondrocyte proliferation in the growth plate, resulting in improved bone growth in a mouse model of OI. However, infusion of neither RNase-treated EVs nor miRNA-depleted EVs enhanced chondrocyte proliferation. Conclusion MSCs exert therapeutic effects in OI by secreting EVs containing miRNA, and EV therapy has the potential to become a novel cell-free therapy for OI that will overcome some of the current limitations in MSC therapy. [ABSTRACT FROM AUTHOR]

Despite years of extensive investigation, the cellular origin of heterotopic ossification (HO) has not been fully elucidated. We have previously shown that circulating bone marrow-derived osteoblast progenitor cells, characterized by the immunophenotype CD45 −/CD44 +/CXCR4 +, contributed to the formation of heterotopic bone induced by bone morphogenetic protein (BMP)-2. In contrast, other reports have demonstrated the contribution of CD45 + hematopoietic derived cells to HO. Therefore, in this study, we developed a novel triple transgenic mouse strain that allows us to visualize CD45 + cells with red fluorescence and mature osteoblasts with green fluorescence. These mice were generated by crossing CD45-Cre mice with Z/RED mice that express DsRed, a variant of red fluorescent protein, after Cre-mediated recombination, and then crossing with Col2.3GFP mice that express green fluorescent protein (GFP) in mature osteoblasts. Utilizing this model, we were able to investigate if hematopoietic derived cells have the potential to give rise to mature osteoblasts. Analyses of this triple transgenic mouse model demonstrated that DsRed and GFP did not co-localize in either normal skeletogenesis, bone regeneration after fracture, or HO. This indicates that in these conditions hematopoietic derived cells do not differentiate into mature osteoblasts. Interestingly, we observed the presence of previously unidentified DsRed positive bone lining cells (red BLCs) which are derived from hematopoietic cells but lack CD45 expression. These red BLCs fail to produce GFP even under in vitro osteogenic conditions. These findings indicate that, even though both osteoblasts and hematopoietic cells are developmentally derived from mesoderm, hematopoietic derived cells do not contribute to osteogenesis in fracture healing or HO. [ABSTRACT FROM AUTHOR]

Mesenchymal stromal cells (MSCs) as a pharmaceutical for ailments characterized by pathogenic autoimmune, alloimmune and inflammatory processes now cover the spectrum of early- to late-phase clinical trials in both industry and academic sponsored studies. There is a broad consensus that despite different tissue sourcing and varied culture expansion protocols, human MSC-like cell products likely share fundamental mechanisms of action mediating their anti-inflammatory and tissue repair functionalities. Identification of functional markers of potency and reduction to practice of standardized, easily deployable methods of measurements of such would benefit the field. This would satisfy both mechanistic research as well as development of release potency assays to meet Regulatory Authority requirements for conduct of advanced clinical studies and their eventual registration. In response to this unmet need, the International Society for Cellular Therapy (ISCT) addressed the issue at an international workshop in May 2015 as part of the 21st ISCT annual meeting in Las Vegas. The scope of the workshop was focused on discussing potency assays germane to immunomodulation by MSC-like products in clinical indications targeting immune disorders. We here provide consensus perspective arising from this forum. We propose that focused analysis of selected MSC markers robustly deployed by in vitro licensing and metricized with a matrix of assays should be responsive to requirements from Regulatory Authorities. Workshop participants identified three preferred analytic methods that could inform a matrix assay approach: quantitative RNA analysis of selected gene products; flow cytometry analysis of functionally relevant surface markers and protein-based assay of secretome.We also advocate that potency assays acceptable to the Regulatory Authorities be rendered publicly accessible in an "open-access" manner, such as through publication or database collection. [ABSTRACT FROM AUTHOR]

The article discusses the challenges associated with generating data on unproven cell therapies, such as selection of a characterized cell type, technical aspects of cell isolation, and the pre-clinical disease models.

Background aims. Mesenchymal stromal cells (MSCs) have been applied to patients in cell therapy for various diseases. Recently, we introduced a novel MSC separation filter device which could yield approximately 2.5-fold more MSCs from bone marrow in a closed system compared with the conventional open density gradient centrifugation method. MSCs isolated with these two methods were phenotypically similar and met the criteria defining human MSC proposed by the International Society for Cellular Therapy. However, these criteria do not reflect the functional capacity of MSCs. It has been shown that the donor, source, isolation method, culture condition and cryopreservation of MSCs have potential to alter their therapeutic efficacy. To determine the equivalency of MSCs isolated by these two methods, we compared their genomic profiles as an index of their biologic potential and evaluated their growth promoting potential as an index of function. Methods. The gene expression profiles of human MSCs isolated from 5 healthy donors with two distinct methods were obtained from microarray analyses. The functional activity of freshly expanded/cryopreserved MSCs from these two isolation methods was evaluated using an in vitro chondrocyte proliferation assay. Results. Freshly expanded MSCs isolated by these two methods were found to exhibit similar gene expression profiles and equivalent therapeutic effects, while freshly thawed, cryopreserved MSCs lacked all measureable therapeutic activity. Conclusions. The MSC separation device generates genomically and functionally equivalent MSCs compared with the conventionally isolated MSCs, although freshly thawed, cryopreserved MSCs, isolated by either method, are devoid of activity in our bioassay. [ABSTRACT FROM AUTHOR]

CD271 is the low-affinity neurotrophin (p75NTR) receptor that belongs to the tumor necrosis factor receptor superfamily. Because in human epidermis, CD271 is predominantly expressed in transit-amplifying (TA) cells, we evaluated the role of this receptor in keratinocyte differentiation and in the transition from keratinocyte stem cells (KSCs) to progeny. Calcium induced an upregulation of CD271 in subconfluent keratinocytes, which was prevented by CD271 small interfering RNA. Furthermore, CD271 overexpression provoked the switch of KSCs to TA cells, whereas silencing CD271 induced TA cells to revert to a KSC phenotype, as shown by the expression of β1-integrin and by the increased clonogenic ability. CD271+ keratinocytes sorted from freshly isolated TA cells expressed more survivin and keratin 15 (K15) compared with CD271− cells and displayed a higher proliferative capacity. Early differentiation markers and K15 were more expressed in the skin equivalent generated from CD271+ TA than from those derived from CD271− TA cells. By contrast, late differentiation markers were more expressed in skin equivalents from CD271− than in reconstructs from CD271+ TA cells. Finally, skin equivalents originated from CD271− TA cells displayed a psoriatic phenotype. These results indicate that CD271 is critical for keratinocyte differentiation and regulates the transition from KSCs to TA cells. [ABSTRACT FROM AUTHOR]

The authors discuss the issues on hospital exemption (HE) clause for advanced therapy medicinal products (ATMPs) regulation in Europe. Topics discussed include clinical trials (CT) for ATMPs, application and different HE interpretation in European countries including Netherlands, Finland and Germany, and affected stakeholders' concerns.

Most triple-negative breast cancers (TNBCs) exhibit gene expression patterns associated with epithelial-to-mesenchymal transition (EMT), a feature that correlates with a propensity for metastatic spread. Overexpression of the EMT regulator Slug is detected in basal and mesenchymal-type TNBCs and is associated with reduced E-cadherin expression and aggressive disease. The effects of Slug depend, in part, on the interaction of its N-terminal SNAG repressor domain with the chromatin-modifying protein lysine demethylase 1 (LSD1); thus, we investigated whether tranylcypromine [also known as trans-2-phenylcyclopropylamine hydrochloride (PCPA) or Parnate], an inhibitor of LSD1 that blocks its interaction with Slug, suppresses the migration, invasion, and metastatic spread of TNBC cell lines. We show here that PCPA treatment induces the expression of E-cadherin and other epithelial markers and markedly suppresses migration and invasion of TNBC cell lines MDA-MB-231 and BT-549. These effects were phenocopied by Slug or LSD1 silencing. In two models of orthotopic breast cancer, PCPA treatment reduced local tumor growth and the number of lung metastases. In mice injected directly in the blood circulation with MDA-MB-231 cells, PCPA treatment or Slug silencing markedly inhibited bone metastases but had no effect on lung infiltration. Thus, blocking Slug activity may suppress the metastatic spread of TNBC and, perhaps, specifically inhibit homing/colonization to the bone. [ABSTRACT FROM AUTHOR]

Abstract: Transplantation of bone marrow cells leads to engraftment of osteopoietic and hematopoietic progenitors. We sought to determine whether the recently described transient expansion of the host osteoblastic niche after marrow radioablation promotes engraftment of both osteopoietic and hematopoietic progenitor cells. Mice infused with marrow cells 24 hours after total body irradiation (TBI) demonstrated significantly greater osteopoietic and hematopoietic progenitor chimerism than did mice infused at 30 minutes or 6 hours. Irradiated mice with a lead shield over 1 hind limb showed greater hematopoietic chimerism in the irradiated limb than in the shielded limb at both the 6- and 24-hour intervals. By contrast, the osteopoietic chimerism was essentially equal in the 2 limbs at each of these intervals, although it significantly increased when cells were infused 24 hours compared with 6 hours after TBI. Similarly, the number of donor phenotypic long-term hematopoietic stem cells was equivalent in the irradiated and shielded limbs after each irradiation-to-infusion interval but was significantly increased at the 24-hour interval. Our findings indicate that a 24-hour delay in marrow cell infusion after TBI facilitates expansion of the endosteal osteoblastic niche, leading to enhanced osteopoietic and hematopoietic engraftment. [Copyright &y& Elsevier]

Background aims. Adipose tissue is a rich and very convenient source of cells for regenerative medicine therapeutic approaches. However, a characterization of the population of adipose-derived stromal and stem cells (ASCs) with the greatest therapeutic potential remains unclear. Under the authority of International Federation of Adipose Therapeutics and International Society for Cellular Therapy, this paper sets out to establish minimal definitions of stromal cells both as uncultured stromal vascular fraction (SVF) and as an adherent stromal/stem cells population. Methods. Phenotypic and functional criteria for the identification of adipose-derived cells were drawn from the literature. Results. In the SVF, cells are identified phenotypically by the following markers: CD45-CD235a-CD31-CD34+. Added value may be provided by both a viability marker and the following surface antigens: CD 13, CD73, CD90 and CD 105. The fibroblastoid colony-forming unit assay permits the evaluation of progenitor frequency in the SVF population. In culture, ASCs retain markers in common with other mesenchymal stromal/stem cells (MSCs), including CD90, CD73, CD 105, and CD44 and remain negative for CD45 and CD31. They can be distinguished from bone-marrow-derived MSCs by their positivity for CD36 and negativity for CD 106. The CFU-F assay is recommended to calculate population doublings capacity of ASCs. The adipocytic, chondroblastic and osteoblastic differentiation assays serve to complete the cell identification and potency assessment in conjunction with a quantitative evaluation of the differentiation either biochemically or by reverse transcription polymerase chain reaction. Conclusions. The goal of this paper is to provide initial guidance for the scientific community working with adipose-derived cells and to facilitate development of international standards based on reproducible parameters. [ABSTRACT FROM AUTHOR]

Bone marrow transplantation (BMT) can give rise to donor-derived osteopoiesis in mice and humans; however, the source of this activity, whether a primitive osteoprogenitor or a transplantable marrow cell with dual hematopoietic and osteogenic potential, has eluded detection. To address this issue, we fractionated whole BM from mice according to cell surface immunophenotype and assayed the hematopoietic and osteopoietic potentials of the transplanted cells. Here, we show that a donor marrow cell capable of robust osteopoiesis possesses a surface phenotype of c-Kit+ Lin− Sca-1+ CD34−/lo, identical to that of the long-term repopulating hematopoietic stem cell (LTR-HSC). Secondary BMT studies demonstrated that a single marrow cell able to contribute to hematopoietic reconstitution in primary recipients also drives robust osteopoiesis and LT hematopoiesis in secondary recipients. These findings indicate that LTR-HSC can give rise to progeny that differentiate to osteoblasts after BMT, suggesting a mechanism for prompt restoration of the osteoblastic HSC niche following BM injury, such as that induced by clinical BMT preparative regimens. An understanding of the mechanisms that regulate this differentiation potential may lead to novel treatments for disorders of bone as well as methods for preserving the integrity of endosteal hematopoietic niches. [ABSTRACT FROM AUTHOR]

Background aims. Mesenchymal stromal cells (MSCs) have been studied as cell therapy to treat a vast array of diseases. In clinical MSC production, the isolated cells must undergo extensive ex vivo expansion to obtain a sufficient dose of MSCs for the investigational treatment. However, extended tissue culture is fraught with potential hazards, including contamination and malignant transformation. Changes of gene expression with prolonged culture may alter the therapeutic potential of the cells. Increasing the recovery of MSCs from the freshly harvested bone marrow allowing for less ex vivo expansion would represent a major advance in MSC therapy. Methods. Human bone marrow cells from eight healthy donors were processed using a marrow filter device and, in parallel, using buoyant density centrifugation by two independent investigators. The initial nucleated cell recovery and the final yield, immunophenotype and trilineage differentiation potential of second-passage MSCs were examined. Results. The marrow filter device generated significantly greater initial cell recovery requiring less investigator time and resulted in approximately 2.5-fold more MSCs after the second passage. The immunophenotype and differentiation potential of MSCs isolated using the two methods were equivalent and consistent with the defining criteria. The two independent investigators generated comparable results. Conclusions. This novel filter device is a fast, efficient and reliable system to isolate MSCs and should greatly expedite pre-clinical and clinical investigations of MSC therapy. [ABSTRACT FROM AUTHOR]

Abstract: Mise en abyme meaning “placed into abyss or infinite recurrence” is an apt paradigm for the relentless growth of sarcoma cells. Its alternative meaning, “self-reflexive embedding” fits the central role attributed to cancer stem cells (CSCs). Diversely sourced and defined, mesenchymal stem cells (MSCs) may be the cells of sarcoma origin, evolve a CSC phenotype and/or contribute to tumor growth through inherent qualities for homing, neovascularization, paracrine cross-feeding, microvesicle secretion, cell fusion, entosis and immune modulation. Exploiting these qualities, MSC expressing modified forms of the TNF-related apoptosis-inducing ligand (Apo2L/TRAIL) are being developed to complement more conventional radiation and chemotherapy. [Copyright &y& Elsevier]

Objective: Transplantable osteoprogenitors, as well as hematopoietic progenitors, reside in bone marrow. We previously reported the first clinical trial of bone marrow transplantation (BMT) for a genetic disorder of bone, osteogenesis imperfecta. Although the patients demonstrated striking clinical benefits after transplantation, measured osteopoietic engraftment was low and did not seem to be durable. Therefore, we sought an animal model, which closely reflects the clinical experience, to facilitate development of strategies to improve the efficiency of osteoprogenitor engraftment after BMT. Materials and Methods: We transplanted unfractionated bone marrow cells from green fluorescent protein−transgenic mice into lethally irradiated recipients in four combinations of inbred mouse strains: from C57BL/6 into C57BL/6 (C-C), from C57BL/6 into FVB/N (C-F), from FVB/N into C57BL/6 (F-C), and from FVB/N into FVB/N (F-F). At 2 weeks after transplantation, we assessed donor hematopoietic and osteopoietic engraftment by flow cytometry, using a novel mean fluorescence assay, and by immunohistochemical staining for green fluorescent protein. Results: Hematopoietic reconstitution by donor cells was complete in all four combinations. Although osteopoietic engraftment of the transplanted cells was also documented in all the four groups, the magnitude of osteopoietic engraftment differed markedly among the strains where F-F > C-F > F-C > C-C. Conclusion: Our findings indicate that the genetic background of inbred mouse strains affects efficiency of osteopoietic engraftment after BMT. Thus, the murine strain must be considered when comparing experimental outcomes. Moreover, comparing the genetic variation among murine strains may lend insight into the factors governing osteopoietic differentiation of transplanted marrow cells. [ABSTRACT FROM AUTHOR]

The article discusses the characteristics of unproven cellular therapies, including the vague scientific rationale to suggest the potential efficacy of the treatment, insufficient data on safety profile, and lack of a standardized approach to confirm consistency in cell manufacturing.

Objective: Based on the recognition that marrow contains progenitors for bone as well as blood, we undertook the first trial of bone marrow transplantation (BMT) for a genetic disorder of bone, osteogenesis imperfecta. While we documented striking clinical benefit soon after transplantation, the measured level of osteopoietic engraftment was low. To improve the efficacy of BMT for bone disorders, we sought to gain insight into the cellular mechanism of engraftment of transplantable marrow osteoprogenitors. Materials and Methods: We transplanted unfractionated bone marrow harvested from green fluorescent protein-transgenic FVB/N mice into lethally irradiated FVB/N recipients. At 3 weeks posttransplantation, we assessed hematopoietic engraftment by flow cytometry and osteopoietic engraftment by immunohistochemical staining for the green fluorescent protein. Results: We show that engraftment of transplantable marrow osteoprogenitors is saturable with a maximal engraftment of about 15% of all bone cells in the epiphysis and metaphysis of the femur at 3 weeks after transplantation. The number of engrafting sites is not up- or downregulated in response to initial progenitor cell engraftment, and there is no evidence for clonal succession of osteopoietic differentiation of engrafted progenitors. Conclusions: Our findings indicate that the capacity for initial osteopoietic engraftment after BMT is limited and “megadose” stem cell transplantation is unlikely to enhance engraftment. Thus, novel strategies to foster osteopoietic chimerism must be developed. [Copyright &y& Elsevier]

PDAC is the fourth leading cause of cancer death and it is characterized by a mortality rate higher than 90% (Malvezzi et al., 2014). Despite the progress in the use of improved diagnostic methods and development of novel targeted therapies, the overall survival rate has not improved over the last decade with a 5-year survival rate settled around 8% (Siegel et al., 2016). This poor clinical outcome is partially due to a pronounced desmoplastic stromal reaction characterized by a large amount of extracellular matrix and tumour associated fibroblasts (TAF). This highly fibrotic stroma makes an important contribution to PDAC development, progression and drug resistance (Becker et al., 2013; Xu et al., 2014). Since years, we have been developing a gene-therapy strategy based on adipose derived mesenchymal stromal cells (AD-MSC) to deliver the novel variant of the potent anti-cancer agent TRAIL (sTRAIL) (Spano et al., 2019; Rossignoli et al. 2019). Gene modified AD-MSC delivering sTRAIL can reshape the PDAC microenvironment inducing tumour cell apoptosis (Spano et al. 2019). Starting from this concept, we here challenged the gene therapy approach in combination with standard anti-PDAC agents, such as Gemcitabine&Nab/Paclitaxel, as pre-requisite for a phase I/II clinical trial. By a three-dimensional (3D) in vitro platform combining tumor cells and primary TAF isolated from human PDAC specimens, we recreated in vitro a 3D tumor cell culture mimicking the in vivo tumor. This 3D model allows to generate proof-of-concept data for the trio combination GEM&Nab/PTX and AD-MSC sTRAIL in order to support the rationale of this combinatory approach in PDAC patients. Using three PDAC cell lines, with different sensitivity to chemotherapeutics and TRAIL, we represented the tumor complexity and the possible variability of clinical scenario. Our results demonstrated a relevant cytotoxic impact exerted by AD-MSC sTRAIL both alone or in combination with GEM&Nab/PTX against TAF and PDAC cells. The synergistic effect between GEM&Nab/PTX and AD-MSC sTRAIL has been further demonstrated in an orthotopic mouse model, in which mice bearing pancreatic cancer received 2 weekly doses of chemotherapeutics followed by AD-MSC sTRAIL intra tumoral eco-guided injections. These in vitro and in vivo data demonstrated a powerful potential of combining a gene therapy approach with chemotherapy and suggesting the transferability of an anticancer MSC-based approach in patients affected by PDAC. [ABSTRACT FROM AUTHOR]