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Background Degenerative diseases are a major public health concern for the aging population and mesenchymal stem cells (MSCs) have great potential for treating many of these diseases. However, the quantity and quality of MSCs declines with aging, limiting the potential efficacy of autologous MSCs for treating the elderly population. Methods Human bone marrow (BM)-derived MSCs from young and elderly donors were obtained and characterized using standard cell surface marker criteria (CD73, CD90, CD105) as recommended by the International Society for Cellular Therapy (ISCT). The elderly MSC population was isolated into four subpopulations based on size and stage-specific embryonic antigen-4 (SSEA-4) expression using fluorescence-activated cell sorting (FACS), and subpopulations were compared to the unfractionated young and elderly MSCs using assays that evaluate MSC proliferation, quality, morphology, intracellular reactive oxygen species, β-galactosidase expression, and adenosine triphosphate (ATP) content. Results The ISCT-recommended cell surface markers failed to detect any differences between young and elderly MSCs. Here, we report that elderly MSCs were larger in size and displayed substantially higher concentrations of intracellular reactive oxygen species and β-galactosidase expression and lower amounts of ATP and SSEA-4 expression. Based on these findings, cell size and SSEA-4 expression were used to separate the elderly MSCs into four subpopulations by FACS. The original populations (young and elderly MSCs), as well as the four subpopulations, were then characterized before and after culture on tissue culture plastic and BM-derived extracellular matrix (BM-ECM). The small SSEA-4-positive subpopulation representing ~ 8% of the original elderly MSC population exhibited a “youthful” phenotype that was similar to that of young MSCs. The biological activity of this elderly subpopulation was inhibited by senescence-associated factors produced by the unfractionated parent population. After these “youthful” cells were isolated and expanded (three passages) on a “young microenvironment” (i.e., BM-ECM produced by BM cells from young donors), the number of cells increased ≈ 17,000-fold to 3 × 10 9 cells and retained their “youthful” phenotype. Conclusions These results suggest that it is feasible to obtain large numbers of high-quality autologous MSCs from the elderly population and establish personal stem cell banks that will allow serial infusions of “rejuvenated” MSCs for treating age-related diseases.

Introduction Bone marrow-derived mesenchymal stem cells (BM-MSCs) for clinical use should not be grown in media containing fetal bovine serum (FBS), because of serum-related concerns over biosafety and batch-to-batch variability. Previously, we described the preparation and use of a cell-free native extracellular matrix (ECM) made by bone marrow cells (BM-ECM) which preserves stem cell properties and enhances proliferation. Here, we compare colony-forming ability and differentiation of MSCs cultured on BM-ECM with a commercially available matrix (CELLstart™) and tissue culture plastic (TCP) under serum-free conditions. Methods Primary MSCs from freshly isolated bone marrow-derived mononuclear cells or passaged MSCs (P1) were grown in serum-containing (SCM) or serum-free (SFM) media on BM-ECM, CELLstart™, or TCP substrates. Proliferation, cell composition (phenotype), colony-forming unit replication, and bone morphogenetic protein-2 (BMP-2) responsiveness were compared among cells maintained on the three substrates. Results Proliferation of primary BM-MSCs was significantly higher in SCM than SFM, irrespectively of culture substrate, suggesting that the expansion of these cells requires SCM. In contrast, passaged cells cultured on BM-ECM or CELLstart™ in SFM proliferated to nearly the same extent as cells in SCM. However, morphologically, those on BM-ECM were smaller and more aligned, slender, and long. Cells grown for 7 days on BM-ECM in SFM were 20–40 % more positive for MSC surface markers than cells cultured on CELLstart™. Cells cultured on TCP contained the smallest number of cells positive for MSC markers. MSC colony-forming ability in SFM, as measured by CFU-fibroblasts, was increased 10-, 9-, and 2-fold when P1 cells were cultured on BM-ECM, CELLstart™, and TCP, respectively. Significantly, CFU-adipocyte and -osteoblast replication of cells grown on BM-ECM was dramatically increased over those on CELLstart™ (2X) and TCP (4-7X). BM-MSCs, cultured in SFM and treated with BMP-2, retained their differentiation capacity better on BM-ECM than on either of the other two substrates. Conclusions Our findings indicate that BM-ECM provides a unique microenvironment that supports the colony-forming ability of MSCs in SFM and preserves their stem cell properties. The establishment of a robust culture system, combining native tissue-specific ECM and SFM, provides an avenue for preparing significant numbers of potent MSCs for cell-based therapies in patients.

Background Umbilical cord blood (UCB) not only contains hematopoietic stem cells (HSCs), but also non-hematopoietic stem cells (NHSCs) that are able to differentiate into a number of distinct cell types. Based on studies published to date, the frequency of NHSCs in UCB is believed to be very low. However, the isolation of these cells is primarily based on their adhesion to tissue culture plastic surfaces. Methods and results In the current study, we demonstrate that this approach overlooks some of the extremely immature NHSCs because they lack the ability to adhere to plastic. Using a native extracellular matrix (ECM), produced by bone marrow (BM) stromal cells, the majority of the UCB-NHSCs attached within 4 h. The colony-forming unit fibroblast frequency of these cells was 1.5 × 10 4 /10 8 mononuclear cells, which is at least 4000-fold greater than previously reported for UCB-NHSCs. The phenotype of these cells was fibroblast-like and different from those obtained by plastic adhesion; they formed embryonic body-like clusters that were OCT4-positive and expressed other human embryonic stem cell-related markers. Importantly, when implanted subcutaneously for 8 weeks into immunocompromised mice, these ECM-adherent and expanded NHSCs generated three germ layer-derived human tissues including muscle, fat, blood vessel, bone, gland, and nerve. Moreover, injection of these cells into muscle damaged by cryoinjury significantly accelerated muscle regeneration. Conclusions These results indicate that UCB may be a virtually unlimited source of NHSCs when combined with isolation and expansion on ECM. NHSCs may be a practical alternative to embryonic stem cells for a number of therapeutic applications.

Science outreach improves science literacy among the public and communication skills of scientists. However, despite the array of well-documented benefits, robust outreach efforts are often absent from communities which stand to benefit the most from these initiatives. Here, we introduce \"Science Fiesta,\" a graduate student-led outreach initiative which utilizes cultural traditions of South Texas as a vehicle to establish self-sustaining interactions between scientists and their local community. Event assessment surveys indicated that attendees found the event both fun and educational.  At the same time, graduate students who organized the event and participated in outreach reported that they strengthened a variety of professional skills important for their future careers. More importantly, the event had a substantial positive impact on enthusiasm for science outreach.  Both public attendees and graduate students reported that they were likely to participate in future science outreach events, even though a majority of both groups had not been previously involved in outreach efforts. Science Fiesta is a model for a highly effective graduate student-led outreach initiative that is capable of 1) improving public scientific literacy, 2) reinforcing graduate education and career development and 3) creating a culture of science engagement within local communities.

Science outreach improves science literacy among the public and communication skills of scientists. However, despite the array of well-documented benefits, robust outreach efforts are often absent from communities which stand to benefit the most from these initiatives. Here, we introduce \"Science Fiesta,\" a graduate student-led outreach initiative which utilizes cultural traditions of South Texas as a vehicle to establish self-sustaining interactions between scientists and their local community. Event assessment surveys indicated that attendees found the event both fun and educational.  At the same time, graduate students who organized the event and participated in outreach reported that they strengthened a variety of professional skills important for their future careers. More importantly, the event had a substantial positive impact on enthusiasm for science outreach.  Both public attendees and graduate students reported that they were likely to participate in future science outreach events, even though a majority of both groups had not been previously involved in outreach efforts. Science Fiesta is a model for a highly effective graduate student-led outreach initiative that is capable of 1) improving public scientific literacy, 2) reinforcing graduate education and career development and 3) creating a culture of science engagement within local communities.

BackgroundImmune checkpoint inhibitors (ICIs) to date have demonstrated limited activity in advanced ovarian cancer (OC). Folate receptor alpha (FRα) is overexpressed in the majority of OCs and presents an attractive target for a combination immunotherapy to potentially overcome resistance to ICI in OCs. The current study sought to examine clinical and immunologic responses to TPIV200, a multiepitope FRα vaccine administered with programmed death ligand 1 (PD-L1) inhibitor durvalumab in patients with advanced platinum-resistant OC.MethodsFollowing Simon two-stage phase II trial design, 27 patients were enrolled. Treatment was administered in 28-day cycles (intradermal TPIV200 and granulocyte-macrophage colony-stimulating factor (GM-CSF) for 6 cycles and intravenous durvalumab for 12 cycles). Primary endpoints included overall response rate and progression-free survival at 24 weeks. Translational parameters focused on tumor microenvironment, PD-L1 and FRα expression, and peripheral vaccine-specific immune responses.ResultsTreatment was well tolerated, with related grade 3 toxicity rate of 18.5%. Increased T cell responses to the majority of peptides were observed in all patients at 6 weeks (p<0.0001). There was one unconfirmed partial response (3.7%) and nine patients had stable disease (33.3%). Clinical benefit was not associated with baseline FRα or PD-L1 expression. One patient with prolonged clinical benefit demonstrated loss of FRα expression and upregulation of PD-L1 in a progressing lesion. Despite the low overall response rate, the median overall survival was 21 months (13.5–∞), with evidence of benefit from postimmunotherapy regimens.ConclusionsCombination of TPIV200 and durvalumab was safe and elicited robust FRα-specific T cell responses in all patients. Unexpectedly durable survival in this heavily pretreated population highlights the need to investigate the impact of FRα vaccination on the OC biology post-treatment.

The immature phenotype of human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) is a major limitation to the use of these valuable cells for pre-clinical toxicity testing and for disease modeling. Here we tested the hypothesis that human perinatal stem cell derived extracellular matrix (ECM) promotes hiPSC-CM maturation to a greater extent than mouse cell derived ECM. We refer to the human ECM as Matrix Plus (Matrix Plus) and compare effects to commercially available mouse ECM (Matrigel). hiPSC-CMs cultured on Matrix Plus mature functionally and structurally seven days after thaw from cryopreservation. Mature hiPSC-CMs showed rod-shaped morphology, highly organized sarcomeres, elevated cTnI expression and mitochondrial distribution and function like adult cardiomyocytes. Matrix Plus also promoted mature hiPSC-CM electrophysiological function and monolayers’ response to hERG ion channel specific blocker was Torsades de Pointes (TdP) reentrant arrhythmia activations in 100% of tested monolayers. Importantly, Matrix Plus enabled high throughput cardiotoxicity screening using mature human cardiomyocytes with validation utilizing reference compounds recommended for the evolving Comprehensive In Vitro Proarrhythmia Assay (CiPA) coordinated by the Health and Environmental Sciences Institute (HESI). Matrix Plus offers a solution to the commonly encountered problem of hiPSC-CM immaturity that has hindered implementation of these human based cell assays for pre-clinical drug discovery.

The repair of neuronal tissue is a challenging process due to the limited proliferative capacity of neurons. Neural stem cells (NSCs) can aid in the regeneration process of neural tissue due to their high proliferation potential and capacity to differentiate into neurons. The therapeutic potential of these cells can only be achieved if sufficient cells are obtained without losing their differentiation potential. Toward this end, an astrocyte-derived coating (HAc) was evaluated as a promising substrate to promote the proliferation of NSCs. Mass spectroscopy and scanning electron microscopy were used to characterize the HAc. The proliferation rate and the expression of stemness and differentiation markers in NSCs cultured on the HAc were evaluated and compared to the responses of these cells to commonly used coating materials including Poly-L-Ornithine (PLO), and a Human Induced Pluripotent Stem Cell (HiPSC)-based coating. The use of the HAc promotes the in vitro cell growth of NSCs. The expression of the stemness markers Sox2 and Nestin, and the differentiation marker DCX in the HAc group was akin to the expression of these markers in the controls. In summary, HAc supported the proliferation of NSCs while maintaining their stemness and neural differentiation potential.

Purpose Paclitaxel causes the paclitaxel-induced acute pain (PIAP) syndrome. Based on preclinical data, we hypothesized that the protein kinase C (PKC) iota inhibitor, auranofin (a gold salt used for other pain conditions), palliates this pain. Methods In a randomized, double-blinded manner, patients who had suffered this syndrome were assigned a one-time dose of auranofin 6 mg orally on day #2 of the chemotherapy cycle (post-paclitaxel) versus placebo. Patients completed the Brief Pain Inventory and a pain diary on days 2 through 8 and at the end of the cycle. The primary endpoint was pain scores, as calculated by area under the curve, in response to “Please rate your pain by circling the one number that best describes your pain at its worse in the last 24 hours.” Results Thirty patients were enrolled. For the primary endpoint, mean area under the curve of 55 units (standard deviation 19) and 61 units (standard deviation 22) were observed in auranofin-treated and placebo-exposed patients, respectively ( p  = 0.44). On day 8 and at the end of the cycle, pain scores in auranofin-treated patients were more favorable, although differences were not statistically significant. Conclusions In the dose schedule studied, auranofin did not palliate the PIAP syndrome, but delayed beneficial trends suggest further study for this indication.