Benefits Of Cell Therapy Research Articles

Brain repair mechanisms after cell therapy for stroke.

Cell-based therapies hold great promise for brain repair after stroke. While accumulating evidence confirms the preclinical and clinical benefits of cell therapies, the underlying mechanisms by which they promote brain repair remain unclear. Here, we briefly review endogenous mechanisms of brain repair after ischaemic stroke and then focus on how different stem and progenitor cell sources can promote brain repair. Specifically, we examine how transplanted cell grafts contribute to improved functional recovery either through direct cell replacement or by stimulating endogenous repair pathways. Additionally, we discuss recently implemented preclinical refinement methods, such as preconditioning, microcarriers, genetic safety switches and universal (immune evasive) cell transplants, as well as the therapeutic potential of these pharmacologic and genetic manipulations to further enhance the efficacy and safety of cell therapies. By gaining a deeper understanding of post-ischaemic repair mechanisms, prospective clinical trials may be further refined to advance post-stroke cell therapy to the clinic.

Prognosis of hip osteonecrosis after cell therapy with a calculator and artificial intelligence: tenyear collapse-free survival prediction on three thousand and twenty one hips.

Several reports have identified prognostic factors for hip osteonecrosis treated with cell therapy, but no study investigated the accuracy of artificial intelligence method such as machine learning and artificial neural network (ANN) to predict the efficiency of the treatment. We determined the benefit of cell therapy compared with core decompression or natural evolution, and developed machine-learning algorithms for predicting tenyear collapse-free survival in hip osteonecrosis treated with cell therapy. Using the best algorithm, we propose a calculator for "prognosis hip osteonecrosis cell therapy (PHOCT)" accessible for clinical use. A total of 3145 patients with 5261 osteonecroses without collapses were included in this study, comprising 1321 (42%) men and 1824 (58%) women, with a median age of 34 (12-62) years. Cell therapy was the treatment for 3021 hips, core decompression alone for 1374 hips, while absence of treatment was the control group of 764 hips. First, logistic regression and binary logistic regression analysis were performed to compare results of the three groups at tenyears. Then an artificial neural network model was developed for tenyear collapse-free survival after cell therapy. The models' performances were compared. The algorithms were assessed by calibration, and performance, and with c-statistic as measure of discrimination. It ranges from 0.5 to 1.0, with 1.0 being perfect discrimination and 0.5 poor (no better than chance at making a prediction). Among the 3021 hips with cell therapy, 1964 hips (65%) were collapse-free survival at tenyears, versus 453 (33%) among those 1374 treated with core decompression alone, and versus 115 (15%) among 764 hips with natural evolution. We analyzed factors influencing the prediction of collapse-free period with classical statistics and artificial intelligence among hips with cell therapy. After selecting variables, a machine learning algorithm created a prognosis osteonecrosis cell therapy calculator (POCT). This calculator proved to have good accuracy on validation in these series of 3021 hip osteonecroses treated with cell therapy. The algorithm had a c-statistic of 0.871 suggesting good-to-excellent discrimination when all the osteonecroses were mixed. The c-statistics were calculated separately for subpopulations of categorical osteonecroses. It retained good accuracy, but underestimated tenyear survival in some subgroups, suggesting that specific calculators could be useful for some subgroups. This study highlights the importance of multimodal evaluation of patient parameters and shows the degree to which the outcome is modified by some decisions that are within a surgeon's control, as the number of cells to aspirate, the choice of injecting in both the osteonecrosis and the healthy bone, the choice between unilateral or bilateral injection, and the possibility to do a repeat injection. Many disease conditions and the heterogeneities of patients are causes of variation of outcome after cell therapy for osteonecrosis. Predicting therapeutic effectiveness with a calculator allows a good discrimination to target patients who are most likely to benefit from this intervention.

Exosomes and Biomaterials: In Search of a New Therapeutic Strategy for Multiple Sclerosis.

Current efforts to find novel treatments that counteract multiple sclerosis (MS) have pointed toward immunomodulation and remyelination. Currently, cell therapy has shown promising potential to achieve this purpose. However, disadvantages such as poor survival, differentiation, and integration into the target tissue have limited its application. A series of recent studies have focused on the cell secretome, showing it to provide the most benefits of cell therapy. Exosomes are a key component of the cell secretome, participating in the transfer of bioactive molecules. These nano-sized vesicles offer many therapeutical advantages, such as the capacity to cross the blood-brain barrier, an enrichable cargo, and a customizable membrane. Moreover, integrating of biomaterials into exosome therapy could lead to new tissue-specific therapeutic strategies. In this work, the use of exosomes and their integration with biomaterials is presented as a novel strategy in the treatment of MS.

Cell Therapy: Types, Regulation, and Clinical Benefits.

Cell therapy practices date back to the 19th century and continue to expand on investigational and investment grounds. Cell therapy includes stem cell- and non–stem cell-based, unicellular and multicellular therapies, with different immunophenotypic profiles, isolation techniques, mechanisms of action, and regulatory levels. Following the steps of their predecessor cell therapies that have become established or commercialized, investigational and premarket approval-exempt cell therapies continue to provide patients with promising therapeutic benefits in different disease areas. In this review article, we delineate the vast types of cell therapy, including stem cell-based and non–stem cell-based cell therapies, and create the first-in-literature compilation of the different “multicellular” therapies used in clinical settings. Besides providing the nuts and bolts of FDA policies regulating their use, we discuss the benefits of cell therapies reported in 3 therapeutic areas—regenerative medicine, immune diseases, and cancer. Finally, we contemplate the recent attention shift toward combined therapy approaches, highlighting the factors that render multicellular therapies a more attractive option than their unicellular counterparts.

Autologous cell therapy in diabetes‑associated critical limb ischemia: From basic studies to clinical outcomes (Review)

Cell therapy is becoming an attractive alternative for the treatment of patients with no‑option critical limb ischemia (CLI). The main benefits of cell therapy are the induction of therapeutic angiogenesis and neovascularization that lead to an increase in blood flow in the ischemic limb and tissue regeneration in non‑healing cutaneous trophic lesions. In the present review, the current state of the art of strategies in the cell therapy field are summarized, focusing on intra‑operative autologous cell concentrates in diabetic patients with CLI, examining different sources of cell concentrates and their mechanisms of action. The present study underlined the detrimental effects of the diabetic condition on different sources of autologous cells used in cell therapy, and also in delaying wound healing capacity. Moreover, relevant clinical trials and critical issues arising from cell therapy trials are discussed. Finally, the new concept of cell therapy as an adjuvant therapy to increase wound healing in revascularized diabetic patients is introduced.

SRT1720 Pretreatment Promotes Mitochondrial Biogenesis of Aged Human Mesenchymal Stem Cells and Improves Their Engraftment in Postinfarct Nonhuman Primate Hearts.

Declined function of aged mesenchymal stem cells (MSCs) diminishes the benefits of cell therapy for myocardial infarction (MI). Our previous study has demonstrated that SRT1720, a specific SIRT1 activator, could protect aged human MSCs (hMSCs) against apoptosis. The purpose of the present study was to investigate the role of mitochondria in the antiapoptotic effects of SRT1720. In addition, we established a nonhuman primate MI model to evaluate cell engraftment of SRT1720-pretreated aged hMSCs (SRT1720-OMSCs). A hydrogen peroxide (H2O2)-induced apoptosis model was established in vitro to mimic MI microenvironment. Compared with vehicle-treated aged hMSCs (Vehicle-OMSCs), SRT1720-OMSCs showed alleviated apoptosis level, significantly decreased caspase-3 and caspase-9 activation, and reduced release of cytochrome c when subjected to H2O2 treatment. Mitochondrial contents were compared between young and aged hMSCs and our data showed that aged hMSCs had lower mitochondrial DNA (mtDNA) copy numbers and protein expression levels of components of the mitochondrial electron transport chain (ETC) than young hMSCs. Also, treatment with SRT1720 resulted in enhanced MitoTracker staining, increased mtDNA levels and expression of mitochondrial ETC components in aged hMSCs. Furthermore, SRT1720-OMSCs exhibited elevated mitochondrial respiratory capacity and higher mitochondrial membrane potential. In vivo study demonstrated that SRT1720-OMSCs had higher engraftment rates than Vehicle-OMSCs at 3 days after transplantation into the infarcted nonhuman primate hearts. Taken together, these results suggest that SRT1720 promotes mitochondrial biogenesis and function of aged hMSCs, which is involved in its protective effects against H2O2-induced apoptosis. These findings encourage further exploration of the optimization of aged stem cells function via regulating mitochondrial function.

Abstract 13427: Extracellular Vesicles Improve Heart Function Without Inducing the Generation of New Cardiomyocytes

Introduction: Extracellular Vesicles (EV) recapitulate the benefits of cell therapy for heart repair. Their mechanism of action remains unsettled. Hypothesis: EV may contribute to heart repair by de novo cardiogenesis. Methods: To answer this question, we used 2 bi-transgenic mouse models: the fate-mapping MerCreMer/ZEG and the Mosaic Analysis With Double Markers (MADM). Myocardial infarction was induced by permanent coronary artery ligation. Those with a LVEF ≤ 45% were treated 3 weeks later with EV (from human iPS-derived cardiovascular progenitor cells; 10x10 9 particles) or PBS, injected under echo guidance in the peri-infarcted area (MerCreMer/ZEG: n=15/group and MADM: n=6/group). To track endogenous cardiomyocyte (CM) proliferation, we used EdU labeling in MerCreMer/ZEG delivered by osmotic pumps implanted for 7-10 days post-injection and biphoton microscopy in MADM models. Cardiac function was assessed 4-6 weeks after injection by echocardiography and MRI, blinded to treatment group. Hearts were then subjected to histological and transcriptomic analyses (qPCR and genome-wide microarray). Results: In PBS controls, EF remained stable over time in MerCreMer/ZEG mice and decreased from 34.5% ± 6.0% to 30.7% ± 7.5% in MADM mice by the end of the study. Conversely, EV injections increased EF from 32.1% ± 9.5% to 36.1% ± 7.45 % in MerCreMer/ZEG and from 36.2 %± 8.7% to 40.5% ± 8.9% in MADM mice. A significant difference in the change from baseline was found between EV and controls: 20.7% ± 10.5 % (p=0.048) and 28.0% ± 11.0 %, (p=0.045) for MerCreMer/ZEG and MADM groups, respectively. This improvement was confirmed by MRI in MerCreMer/ZEG mice (p=0.05). Improvement in EF was unrelated to the appearance of new CM, as shown by the absence of difference in TnT+/EdU+/GFP+ cell numbers and the lack of activation of the YAP/TAZ pathway between control and EV groups. However, EV reduced infarct size by 11.9% ± 5.75% (p=0.04), which was accompanied by decreased expression of 4 pro-fibrotic genes (Col1a2, Col3a1, Lox, Col1a2 by qPCR) in heart tissue and a 2.13X overexpression of the anti-fibrotic miRNA 133a-1 compared to controls (n=3/group; p=0.001). Conclusions: EV likely improve cardiac function by modulation of fibrosis rather than by de novo cardiogenesis.

Biothérapies pour les troubles de l’érection et la maladie de la Peyronie : ou en est-on ?

Clinical trials of cell therapy for erectile dysfunction (ED) and Peyronie's disease (PD) were recently conducted after preclinical studies. The aims of this study are to give an update on biotherapy for ED and PD and to describe the regulatory framework for these therapies. A literature review was performed through PubMed and Clinical.trials.gov addressing cell therapy for ED and PD and using following keywords "erectile dysfunction", "Peyronie's disease", "stem cell", and "platelet-rich plasma". Preclinical studies in rodent models have shown the potential benefit of cell therapy for ED after radical prostatectomy or caused by metabolic diseases, and PD. The tissues used to obtain the therapeutic product were bone marrow, adipose tissue and blood (PRP, platelet-rich plasma). Mechanism of action was shown to be temporary and mainly paracrine. Four clinical trials were published concerning ED after radical prostatectomy and in diabetic patients and one for PD. Eleven clinical trials including three randomized trials are currently going on. Preclinical and preliminary clinical results suggested the possibility to improve spontaneous erectile function and response to pharmaceutical treatment in initially non-responder patients. This effect is mediated by an improvement of penile vascularization. A reduction of penile curvature without side effect was noted after injections into the plaque of PD patients. Most of these therapeutic strategies using autologous cells were considered as "Advanced Therapy Medicinal Products" with strict regulatory frameworks imposing heavy constraints, in particular in case of "substantial" modification of the cells. The regulatory framework remains unclear and more permissive for PRP and cell therapy processes with extemporaneous preparation/injection and no "substantial" modifications. First results on cell therapy for ED and PD are promising. The regulatory framework can significantly change according to cell preparations and origins leading to various constraints. This regulatory framework is crucial to consider for the choice of the procedure.

P1646Do Extracellular Vesicles repair chronic ischemic heart disease by replenishing the cardiomyocyte pool?

Abstract Introduction Extracellular Vesicles (EV) seem to mediate the benefits of cell therapy for ischemic heart failure. Although their mechanism of action remains poorly understood, one hypothesis is that they might trigger the generation of new cardiomyocytes. The doubly transgenic fate-mapping MerCreMer/ZEG mice model was thus used to distinguish whether these putative new cardiomyocytes originated from the division of preexisting ones (GFP+, Troponin T [TnT+], EdU+) or differentiated from endogenous progenitors, in which case they would stain positive for TnT+/EdU+ but negative for GFP. Methods Myocardial infarction was induced in 35 MerCreMer/ZEG mice by permanent occlusion of the left anterior descending coronary artery. Three weeks later, the surviving mice (n=18) with a left ventricular ejection fraction (LVEF) ≤45% received transcutaneous echo-guided injections in the peri-infarct myocardium of either EV (from 1.4 million human iPS-derived cardiovascular progenitor cells; 10 billion particles, n=9) or PBS (n=9); osmotic pumps were implanted to deliver EdU for 7 days in order to track the proliferation of new and native cardiomyocytes. Four-6 weeks after treatment all mice were evaluated by echocardiography (n=9 per group) and MRI (7 in each group), and then sacrificed for histological assessment, blindly. Results Based on echocardiography (MRI data pending), EV improved LVEF by 16% relative to baseline while a decrease of 4% was observed in the PBS group (p=0.46). The number of new cardiomyocytes (TnT+/EdU+/GFP+) did not significantly differ between the EV-treated hearts and the controls, and averaged 0.54% of the total heart cell content in infarct, peri-infarct and remote areas. However, EV treatment better preserved preexisting GFP+/WGA+/TnT+ cardiomyocytes in the peri-infarct area as their number was greater by 5.15% compared to PBS (32 sections analyzed for each mouse). Compared to the PBS control group, EV delivery was also associated with a 2.5% decrease in fibrosis, a reduction of infarct size by 14.9%, and an increase in angiogenesis in the peri-infarct area (with a between-group absolute difference of 71 capillaries, on the basis of isolectin staining). Conclusions EV secreted by iPS-derived cardiovascular progenitors improve the function of chronically infarcted hearts. Preservation of the existing cardiomyocyte pool and limitation of adverse remodeling and scarred tissue, likely favored by increased neoangiogenesis, are the main mechanisms mediated by the EV, while fate mapping allowed to exclude the generation of new cardiomyocytes.

Magnetic Iron Oxide Nanoparticle Labeling of Photoreceptor Precursors for Magnetic Resonance Imaging.

This study describes the methods and results of superparamagnetic iron oxide nanoparticle (SPION) labeling and magnetic resonance imaging (MRI) tracking of human embryonic stem cell-derived photoreceptor precursors transplanted into the subretinal space of Royal College of Surgeons rats. SPION labeling and MRI tracking provide information about the biodistribution of transplanted photoreceptor precursors, which is necessary for improving the functional benefits of cell therapy for degenerative retinal diseases.

Cell therapy for orofacial bone regeneration: A systematic review and meta-analysis.

The objective of the present review was to answer the focused question: what is the effect of cell therapy in terms of orofacial bone regeneration compared to grafting with only biomaterial scaffolds and/or autogenous bone? Electronic databases were searched for relevant controlled clinical and pre-clinical (large-animal) studies. Separate meta-analyses of quantitative data regarding histological or radiographic new bone formation were performed. Forty-seven eligible clinical and 57 pre-clinical studies were included. Clinical studies were categorized based on the use of "minimally manipulated" whole tissues (e.g., bone marrow) or ex vivo expanded cells from "uncommitted" (bone marrow, adipose tissue) or "committed" sources (periosteum, bone). Based on limited and heterogeneous clinical evidence, implantation of cells (mostly whole bone marrow), in combination with biomaterial scaffolds results in bone regeneration which is (a) superior compared to implantation of scaffolds alone in sinus and horizontal ridge augmentation, and (b) comparable to autogenous bone in alveolar cleft repair. Although current evidence points to the benefits of cell therapy in certain clinical indications, it is unclear whether the use of ex vivo expanded cells, either uncommitted or committed, is superior to whole tissue fractions in terms of bone regeneration. The relatively larger effect sizes in favour of cell therapy observed in pre-clinical studies are diminished in clinical trials. Future controlled studies should include cost-effectiveness analyses to guide clinical decision-making.

Cell-Based Therapy in Cardiac Regeneration: An Overview.

Although pioneering preclinical research on the use of cell therapy for cardiac regeneration was conducted in the last quarter of the 20th century,1,2 a preponderance of advances have occurred in the 21st century, making this a relatively young field. In the first important clinical trial of cardiac cell therapy, begun in 2001, Menasche et al3 implanted autologous skeletal myoblasts into postinfarct scar at the time of coronary artery bypass surgery. Although the transplanted cells remained viable and exhibited contraction, they formed the nidus for serious ventricular tachyarrhythmias, which led to premature discontinuation of the trial. Despite this outcome, the trial energized the field, accelerating both preclinical and clinical research, albeit not with skeletal myoblasts. The extensive progress in cardiac regeneration is reviewed in this Compendium, and as occurs frequently in science, important observations have led to more questions and challenges (Table). View this table: Table. Important Challenges to Cell Therapy for Cardiac Regeneration Many cell types have been evaluated as candidates for cardiac regeneration. Among the earliest clinical trials, Zeiher’s group infused autologous bone marrow-derived progenitor cells into the coronary arteries of patients with acute,4 as well as healed myocardial infarction (MI)5 and reported improvements in left ventricular (LV) function. However, these results have not been fully confirmed by later studies, as pointed out in the review in the Compendium by Banarjee, Bolli, and Hare.6 Pittenger et al7 were among the first to direct attention to bone marrow-derived (stromal) mesenchymal stem cells (MSCs), emphasizing that these cells proliferated extensively in culture and suggesting that they could be attractive candidates for transplantation. In 2004, Chen et al8 reported that intracoronary infusion of autologous bone marrow-derived MSCs improved cardiac function. Zimmet and Hare pointed out that MSCs lack histocompatibility type II markers and elude rejection by …

Potential clinical benefits of cell therapy in coronary heart disease: an update.

Cell therapy is a central issue of regenerative medicine and is raising a growing interest in the scientific community, but its full therapeutic potential in coronary heart disease (CHD) has not been reached yet. Several different methods, cell types, delivery routes, and supporting techniques have been attempted and improved to elicit cardiac regeneration in CHD, but only some of them showed a really convincing potential for the use in clinical practice. Here we provide an update on approaches and clinical trials of cell therapy applied to CHD, which are ongoing or that have been realized in the last 5 years. Moreover, we discuss the evidence collected so far in favor or against the validity of stem cell therapy for CHD. In particular, we review and comment the recent advances in cell therapy applied to CHD, the most promising cell types, delivery strategies, biochemical and engineering techniques that have been adopted in this context.

A mechanistic roadmap for the clinical application of cardiac cell therapies.

The development of cells for regenerative therapy has encountered many pitfalls on its path to clinical translation. In cardiology, clinical studies of heart-targeted cell therapies began two decades ago, yet progress towards reaching an approved product has been slow. In this Perspective, I provide an overview of recent cardiac cell therapies, with a focus on the hurdles limiting the translation of cell products from research laboratories to clinical practice. By focusing on heart failure as a target indication, I argue that strategies for overcoming limitations in clinical translation require an increasing emphasis on mechanism-supported efficacy, rather than on phenomenological observations. As research progresses from cells to paracrine mechanisms to defined factors, identifying those defined factors that are involved in achieving superior therapeutic efficacy will better inform the use of cells as therapeutic candidates. The next generation of cell-free biologics may provide the benefits of cell therapy without the intrinsic limitations of whole-cell products.

Exosome-Mediated Benefits of Cell Therapy in Mouse and Human Models of Duchenne Muscular Dystrophy.

SummaryGenetic deficiency of dystrophin leads to disability and premature death in Duchenne muscular dystrophy (DMD), affecting the heart as well as skeletal muscle. Here, we report that clinical-stage cardiac progenitor cells, known as cardiosphere-derived cells (CDCs), improve cardiac and skeletal myopathy in the mdx mouse model of DMD. Injection of CDCs into the hearts of mdx mice augments cardiac function, ambulatory capacity, and survival. Exosomes secreted by human CDCs reproduce the benefits of CDCs in mdx mice and in human induced pluripotent stem cell-derived Duchenne cardiomyocytes. Surprisingly, CDCs and their exosomes also transiently restored partial expression of full-length dystrophin in mdx mice. The findings further motivate the testing of CDCs in Duchenne patients, while identifying exosomes as next-generation therapeutic candidates.

Concise Review: Is Cardiac Cell Therapy Dead? Embarrassing Trial Outcomes and New Directions for the Future.

Stem cell therapy is a promising strategy for tissue regeneration. The therapeutic benefits of cell therapy are mediated by both direct and indirect mechanisms. However, the application of stem cell therapy in the clinic is hampered by several limitations. This concise review provides a brief introduction into stem cell therapies for ischemic heart disease. It summarizes cell‐based and cell‐free paradigms, their limitations, and the benefits of using them to target disease. stem cells translational medicine 2018;7:354–359

Platelet-rich plasma-derived scaffolds increase the benefit of delayed mesenchymal stromal cell therapy after severe traumatic brain injury

BackgroundCell therapy using mesenchymal stromal cells (MSCs) offers new perspectives in the treatment of traumatic brain injury (TBI). The aim of the present study was to assess the impact of platelet-rich plasma scaffolds (PRPS) as support of MSCs in a delayed phase after severe TBI in rats. MethodsTBI was produced by weight-drop impact to the right cerebral hemisphere. Two months after TBI, four experimental groups were established; saline, PRPS, MSCs in saline, or MSCs in PRPS was transplanted into the area of brain lesion through a small hole. All groups were evaluated in the course of the following 12 months after therapy and the animals were then humanely killed. ResultsOur results showed that a greater functional improvement was obtained after the administration of MSCs in PRPS compared with the other experimental groups. DiscussionPRPS enhanced the benefit of cell therapy with MSCs to treat chronic brain damage in rats that suffered a severe TBI. The present findings suggest that the use of intralesional MSCs supported in PRPS may be a strategy of tissue engineering for patients with established neurological severe dysfunction after a TBI.

Protein-engineered hydrogels enhance the survival of induced pluripotent stem cell-derived endothelial cells for treatment of peripheral arterial disease.

A key feature of peripheral arterial disease (PAD) is damage to endothelial cells (ECs), resulting in lower limb pain and restricted blood flow. Recent preclinical studies demonstrate that the transplantation of ECs via direct injection into the affected limb can result in significantly improved blood circulation. Unfortunately, the clinical application of this therapy has been limited by low cell viability and poor cell function. To address these limitations we have developed an injectable, recombinant hydrogel, termed SHIELD (Shear-thinning Hydrogel for Injectable Encapsulation and Long-term Delivery) for cell transplantation. SHIELD provides mechanical protection from cell membrane damage during syringe flow. Additionally, secondary in situ crosslinking provides a reinforcing network to improve cell retention, thereby augmenting the therapeutic benefit of cell therapy. In this study, we demonstrate the improved acute viability of human induced pluripotent stem cell-derived endothelial cells (iPSC-ECs) following syringe injection delivery in SHIELD, compared to saline. Using a murine hind limb ischemia model of PAD, we demonstrate enhanced iPSC-EC retention in vivo and improved neovascularization of the ischemic limb based on arteriogenesis following transplantation of iPSC-ECs delivered in SHIELD.

Evaluation of Hydrogels Presenting Extracellular Matrix-Derived Adhesion Peptides and Encapsulating Cardiac Progenitor Cells for Cardiac Repair.

Cell therapy is an emerging paradigm for the treatment of heart disease. In spite of the exciting and promising preclinical results, the benefits of cell therapy for cardiac repair in patients have been modest at best. Biomaterials-based approaches may overcome the barriers of poor differentiation and retention of transplanted cells. In this study, we prepared and tested hydrogels presenting extracellular matrix (ECM)-derived adhesion peptides as delivery vehicles for c-kit+ cardiac progenitor cells (CPCs). We assessed their effects on cell behavior in vitro as well as cardiac repair in rats undergoing ischemia reperfusion. Hydrogels presenting the collagen-derived GFOGER peptide induced cardiomyocyte differentiation of CPCs as demonstrated by increased expression of cardiomyocyte structural proteins. However, conditioned media obtained from GFOGER hydrogels showed lower levels of secreted reparative factors. Interestingly, following injection in rats undergoing ischemia-reperfusion, treatment with CPCs encapsulated in nonadhesive RDG-presenting hydrogels resulted in the preservation of cardiac contractility and attenuation of postinfarct remodeling whereas the adhesion peptide-presenting hydrogels did not induce any functional improvement. Retention of cells was significantly higher when delivered with nonadhesive hydrogels compared to ECM-derived peptide gels. These data suggest that factors including cell differentiation state, paracrine factors and interaction with biomaterials influence the effectiveness of biomaterials-based cell therapy. A holistic consideration of these multiple variables should be included in cell-biomaterial combination therapy designs.

RNA-SEQ DATA ANALYSIS IDENTIFIES STEM CELL TRANSCRIPTOMIC SIGNATURES UNDERPINNING THE THERAPEUTIC EFFECTIVENESS OF PATIENT CELLS IN THE IMPACT-CABG TRIAL

Therapeutic benefits of cell therapy remain mitigated due to factors including cell phenotypes and their poor survival and function in pathologic heart. Whereas first generation of advances focused on cell selection, delivery and a broad understanding of mechanisms involved in therapy success, the next advances will come from decoding complex biological pathways underpinning regenerative potential of cells from different patients. IMPACT-CABG trial represents the first North American phase II multicenter randomized study of intra-myocardial delivery of autologous CD133+ cells in chronic cardiomyopathy patients undergoing CABG. With banked stem cells from this trial, we have the opportunity to correlate the patient’s clinical outcome with cellular gene expression profiles. Our goal is to identify genomic signatures responsible for therapeutic effectiveness and identify pre-treatments from our drug discovery platform that could activate cellular phenotypes replicating those of patients responding to cell therapy. In this exploratory study, expression of 20,800 human genes (Ion AmpliSeq) are analyzed in high-throughput format using CD133+ stem cells from 13 patients classified as responders (≥5% LVEF and/or ≤10% left ventricular volumes) vs non-responders according to cardiac fMRI comparing pre- and 6-month post-treatment changes. Differential expression and pathway analysis are performed using computational tools including DESeq2, GAGE (Generally Applicable GeneSet Enrichment for Pathways Analysis), PathView and R. Pathway analyses show significant association in responders with genes related to cytokine production, activity and receptor interaction, cell adhesion molecules, regulation of kinase cascades (p < 0.05). Several other comparisons were performed to characterize gene expression vs patient demographics. The general pattern of activity was replicated in human mesenchymal stem cells (hMSC) by short ex vivo pharmacological conditioning with Celastrol, an HSP90 targeting compound. Celastrol activates kinases PI3K/Akt and ERK1/2 within 5min, upregulates HSP70 and HO-1 mRNAs (>30-fold) as well as VEGF in cells maintained in normoxic (2.7-fold) or hypoxic condition (1.3-fold, p < 0.05). Celastrol improves hMSC viability during hypoxic or oxidative challenges. Proteomic analysis of culture conditioned-media shows upregulation (>2-fold) of over 100 proteins, including HSPs, growth factors, antioxidants, cytokines indicating improved paracrine potential. IMPACT-CABG responder’s stem cells express gene sets associated with paracrine potential, cell engraftment and survival that can be mimicked by an ex vivo pharmacological pre-conditioning to improve stem cell therapeutic potential. Information gathered will be used in IMPACT-CABG II trial involving a first of its kind precision pharmaco-optimization strategy (USPTO62/350,258 patent pending) to harness the full potential of cellular cardiomyoplasty using CD133+ cells.