Cell-based Therapy For Patients Research Articles

Cell-based therapy for patients after stroke

Cell-based therapy for patients after stroke

Safe and Effective Re-Induction Of Complete Remissions In Adults With Relapsed B-ALL Using 19-28z CAR CD19-Targeted T Cell Therapy

▪Although most adults diagnosed with B-ALL can be induced into a first complete remission (CR1 rates of approximately 80-90%), a majority will relapse and develop chemorefractory disease. Novel, non-chemotherapy based treatments are needed for this group of patients.We have developed a novel CD19-targeted T cell-based therapy for patients with B cell malignancies. We isolate T cells from patients with relapsed/refractory B-ALL and genetically modify them with a chimeric antigen receptor (CAR) construct, termed 19-28z, which comprises a CD19 binding domain fused to the signaling domains of the CD28 costimulatory receptor and the ζ chain of the CD3 complex. CD19 is a universal B cell antigen expressed on all normal and malignant B cells. Expression of the 19-28z CAR by a T cell promotes binding of the CD19 antigen and triggers cytotoxicity, cytokine release and proliferation upon engagement of CD19.We are conducting a Phase I clinical protocol in adults with relapsed/refractory B-ALL (NCT01044069). Enrolled patients are leukapheresed and then re-induced with salvage chemotherapy. A T cell infusion (3 x 106 19-28z CAR T cells/kg) is administered following conditioning chemotherapy. We now describe the results from this Phase I protocol. Thirteen adults have been treated to date: eleven were enrolled with relapsed/refractory disease, while the other 2 were enrolled and leukapheresed during CR1, but not treated until they relapsed. The age of the patients ranged from 23 to 74 with a median age of 42. Three of the 13 patients had Philadelphia-chromosome positive B-ALL, which is considered the most negative genetic risk factor for adults with B-ALL. We were able to achieve the required T cell dose, despite collecting patients with high blast counts or marked lymphopenias, in all but one patient. Seven of the 13 patients were infused with 19-28z CAR T cells while they had gross residual disease (>5 to 70% blasts in the BM). The remaining patients had MRD, detected by flow cytometry or deep sequencing, at the time of 19-28z CAR T cell infusion.Six patients developed toxicities including high-grade fevers (>40°C), hypotension, hypoxia, mental status changes, and seizures. These episodes ran for approximately one week before they were halted by treatment with steroids or tocilizumab. The other 7 patients did not experience toxicities. All patients completely recovered and were able to leave the hospital. The occurrence of toxicities correlated with tumor burden so that patients with gross residual disease (>5% blasts in BM) developed toxicities, while patients with MRD had no evidence of toxicities.Ten out of the 12 patients with detectable disease before T cell infusion developed MRD- responses such that 5 of the patients with gross residual disease (blasts > 5% in BM) became MRD- and 5 MRD+ patients became MRD-. The rapidity of the responses was quite remarkable with MRD- results obtained as early as 7 -14 days after T cell infusion. Furthermore, despite the poor predicted outcomes of relapsed Ph+ B-ALL we were able to get these patients MRD-, as detected by both deep sequencing for the IgH rearrangement and qPCR for the bcr-abl transcript. ConclusionThe potent induction of MRD- responses and the reversibility of toxicities occurring in a subset of patients strongly support integrating this therapy in the modern paradigm for B-ALL therapy, by facilitating access to allogeneic-stem cell transplantation (SCT) for patients with relapsed B-ALL. Indeed, out of the 13 patients treated to date, 4 underwent an allo-SCT and 5 are being prepared for an allo-SCT. Of the remaining 4 patients, 1 is a non-responder (a patient with extramedullary disease, but no disease in the bone marrow), 1 relapsed (not eligible for allo-SCT), 1 is in CR2 (medically not eligible for allo-SCT), and 1 has not been evaluated for treatment response yet. Overall, the results from this Phase I protocol demonstrate that toxicities associated with this therapy are predictable and manageable. Furthermore, the remarkable MRD- re-induction rate and facilitation for allo-SCT we report here warrant further evaluation of this therapy in a Phase II protocol. Disclosures:No relevant conflicts of interest to declare.

Evaluation of clinical experience using cell-based therapies in patients with spinal cord injury: a systematic review

Using a systematic approach, the authors evaluated the current utilization, safety, and effectiveness of cellular therapies for traumatic spinal cord injuries (SCIs) in humans. A systematic search and critical review of the literature published through mid-January 2012 was performed. Articles included in the search were restricted to the English language, studies with at least 10 patients, and those analyzing cellular therapies for traumatic SCI. Citations were evaluated for relevance using a priori criteria, and those that met the inclusion criteria were critically reviewed. Each article was then designated a level of evidence that was developed by the Oxford Centre for Evidence-Based Medicine. The initial literature search identified 651 relevant articles, which decreased to 350 after excluding case reports and reviews. Evaluation of articles at the title/abstract level, and later at the full-text level, limited the final article set to 12 papers. The following cellular therapies employed in humans with SCI are reviewed: bone marrow mesenchymal and hematopoietic stem cells (8 studies), olfactory ensheathing cells (2 studies), Schwann cells (1 study), and fetal neurogenic tissue (1 study). Overall the quality of the literature was very low, with 3 Grade III levels of evidence and 9 Grade IV studies. Several different cellular-mediated strategies for adult SCI have been reported to be relatively safe with varying degrees of neurological recovery. However, the literature is of low quality and there is a need for improved preclinical studies and prospective, controlled clinical trials.

Adult human olfactory epithelial-derived progenitors: a potential autologous source for cell-based treatment for Parkinson's disease.

Human adult olfactory epithelial-derived neural progenitors (hONPs) can differentiate along several neural lineages in response to morphogenic signals in vitro. A previous study optimized the transfection paradigm for the differentiation of hONPs to dopaminergic neurons. This study engrafted cells modified by the most efficient transfection paradigm for dopaminergic neural restriction and pretransfected controls into a unilateral neurotoxin, 6-hydroxydopamine-induced parkinsonian rat model. Approximately 35% of the animals engrafted with hONPs had improved behavioral recovery as demonstrated by the amphetamine-induced rotation test, as well as a corner preference and cylinder paw preference, over a period of 24 weeks. The pre- and post-transfected groups produced equivalent responses, indicating that the toxic host environment supported hONP dopaminergic differentiation in situ. Human fibroblasts used as a cellular control did not diminish the parkinsonian rotational deficits at any point during the study. Increased numbers of tyrosine hydroxylase (TH)-positive cells were detected in the engrafted brains compared with the fibroblast-implanted and medium-only controls. Engrafted TH-positive hONPs were detected for a minimum of 6 months in vivo; they were multipolar, had long processes, and migrated beyond their initial injection sites. Higher dopamine levels were detected in the striatum of behaviorally improved animals than in equivalent regions of their nonrecovered counterparts. Throughout these experiments, no evidence of tumorigenicity was observed. These results support our hypothesis that human adult olfactory epithelial-derived progenitors represent a unique autologous cell type with promising potential for future use in a cell-based therapy for patients with Parkinson's disease.

Cell Therapy for the Treatment of Chronic Ischemic Heart Disease

Over the last decade, much was learned about the biology of several types of stem and progenitor cells. It has become apparent that various cell sources may have the capacity to promote cardiomyogenesis and new blood vessel formation through different mechanisms, forming the rationale for cell-based therapy in patients with chronic ischemic heart disease. After initial clinical studies have provided evidence for safety of cell administration, larger randomized trials demonstrated variable effects on myocardial perfusion and contractile performance. Although cell-based therapy is a promising strategy for the treatment of myocardial disease, many questions remain to be answered with respect to the optimal cell type, delivery route and mechanism of action in order to improve the outcome of cardiac cell therapy. This paper aims to provide an overview of the methods available to apply cell-based therapy in chronic ischemic myocardial disease. The different cell types that have been tested in (pre)clinical trials and their proposed mechanism of action will be discussed, along with the possible routes of cell delivery. Furthermore, the experience from experimental and clinical studies will be summarized, and innovative strategies to enhance the efficacy of cell therapy, for example by improving cell retention and survival, will be reviewed.

Novel Stem/Progenitor Cell Population from Murine Tracheal Submucosal Gland Ducts with Multipotent Regenerative Potential

The airway epithelium is in direct contact with the environment and therefore constantly at risk for injury. Basal cells (BCs) have been found to repair the surface epithelium (SE), but the contribution of other stem cell populations to airway epithelial repair has not been identified. We demonstrated that airway submucosal gland (SMG) duct cells, in addition to BCs, survived severe hypoxic-ischemic injury. We developed a method to isolate duct cells from the airway. In vitro and in vivo models were used to compare the self-renewal and differentiation potential of duct cells and BCs. We found that only duct cells were capable of regenerating SMG tubules and ducts, as well as the SE overlying the SMGs. SMG duct cells are therefore a multipotent stem cell for airway epithelial repair This is of importance to the field of lung regeneration as determining the repairing cell populations could lead to the identification of novel therapeutic targets and cell-based therapies for patients with airway diseases.

Cell‐based therapy for patients with vascular dementia

The homeostasis of neuronal cells is maintained by the cerebral circulation and blood-brain barrier. Circulating bone marrow-derived immature cells, including CD34-positive (CD34+) cells, have been implicated in homeostasis of the cerebral microvasculature. Decreased levels of circulating CD34+ cells, associated with ageing and/or cardiovascular risk factors, correlate with poor clinical outcomes in patients with cerebrovascular and cardiovascular diseases. Clinical trials with local transplantation of bone marrow-derived immature cells for patients with limb ischaemia, including Buerger's disease and arteriosclerosis obliterans, have been shown to improve impaired microcirculation. In the present review, current findings about the correlation between circulating immature cells and microcirculation are reviewed, and the possibility of novel cell-based therapy in patients with vascular dementia is discussed.

Monitoring T-cell responses in a phase II study of AGS-003, an autologous dendritic cell-based therapy in patients with newly diagnosed advanced stage renal cell carcinoma in combination with sunitinib.

2532 Background: Dendritic cells (DC) are a powerful tool for stimulating cell-mediated immunity through the effects of CD4+ and CD8+ T cells. This phase II study investigated AGS-003, an autologous amplified tumor RNA-loaded DC–based immunotherapy in patients with RCC in combination with sunitinib. AGS-003 stimulates proliferation of CD28 expressing cytotoxic T lymphocytes (CTL), targeted directly to autologous RCC tumor antigens. While sunitinib is capable of inducing tumor regression through inhibition of VEGF activity, it also possesses non-specific immune modulatory effects, which include a noted decrease in regulatory T cells. Therefore, the combination of AGS-003 and sunitinib could result in synergistic effects over that which could be achieved with either modality alone. Methods: Immune monitoring (IM) analysis using multiparametric flow cytometry was performed on PBMC isolated from blood draws collected prior to treatment and after treatment with AGS-003 during combination administration with sunitinib. Results: Results revealed that for all subjects tested, there was a decrease in the percentage of T regulatory cells during combination treatment with AGS-003 and sunitinib compared to pre-therapy baseline levels. With the exception of one outlier, there was a correlation between decreased regulatory T cells and PFS (r2=0.7662). Also, patients treated concurrently with AGS-003 in the presence of sunitinib were able to expand CD28+ memory CTL with a broad range of effector functions. The expansion of tumor antigen-reactive CD28+ CTL revealed a trend between PFS and the change in CD28+ effector memory CTL post-treatment. Nine of 11 subjects with PFS of >10 months demonstrated CTL population increases whereas 2 of 4 subjects with PFS <10 months showed increases in this specific CTL population. Conclusions: We conclude that the combination of sunitinib and AGS-003 can decrease the percentage of T regulatory cells with a concurrent expansion of CD28+ effector memory CTL thereby overcoming tumor-induced immunosuppression and potentially leading to better clinical outcome in terms of PFS.

Innovation in the Treatment of Uremia: Proceedings from the Cleveland Clinic Workshop: Cellular Therapy of Kidney Diseases

The understanding of cellular sources of kidney regeneration has rapidly evolved in the last decade. It is now believed that regeneration occurs predominantly from cells that reside within the injured kidney, with minimal contribution from extra-renal cells. We now know that improved kidney regeneration seen following exogenous administration of stem cells occur predominantly by noncellular paracrine mechanisms. Of all extra-renal stem cells, mesenchymal stem cells (MSC) are the most promising stem cell type for treating kidney diseases. There is an ongoing clinical trial evaluating safety and efficacy of MSC in treating acute kidney injury (AKI). Results of this trial are expected to bring use of MSC closer to the clinical realm. An improved understanding of the small molecules that facilitate kidney regeneration and are secreted by MSC will likely result in the development of new therapies for treating AKI. Identification of adult stem cell markers will result in improved understanding of pathophysiology of kidney diseases and could lead to the development of new cellular therapies. Directed differentiation of stem cells into desired cell types such as erythropoietin producing cells will allow selective replacement of lost kidney function. Cell-based therapies for patients with chronic kidney disease are presently in proof-of-principle stage and are expected to evolve in the coming years with improved understanding of stem cell biology. Technological advancement in cellular therapy is expected to provide improved therapeutic options for patients with kidney diseases in the near future.

Limited value of digital subtraction angiography in the evaluation of cell-based therapy in patients with limb ischemia

Cell-based therapy has been proposed as a novel strategy for patients with severe peripheral arterial disease by stimulating vascular growth. In clinical studies of this therapy, the emphasis has been on demonstrating recovery of clinical parameters, rather than on evaluation of blood flow recovery. Angiography is still the gold standard for the assessment of lower leg arteries. Therefore, we studied the usefulness of angiography in the evaluation of cell-based therapy. Sixteen patients with critical leg ischemia (ischemic rest pain or ulcers), or persistent (>12 months) profound disabling claudication were unilaterally treated with autologous bone marrow-derived mononuclear cells. Pre- and 6 months post-treatment digital subtraction angiographies (DSA) were assessed and compared in a blinded fashion twice by a panel of seven vascular surgeons and interventional radiologists. Inter- and intraobserver variability on qualitative (poor/moderate/rich) and semi-quantitative (increase/no difference/decrease) assessment of collateral circulation were evaluated. Agreement was expressed inter- and intraclass correlation coefficients (CC). Inter- and intraobserver agreement was moderate for the qualitative grading of collateral extent (CC = 0.46 and 0.60, respectively). Agreement was moderate (inter-CC = 0.60) to good (intra-CC = 0.73) for comparing pre- and post-treatment DSA. Clinical response was based on limb salvage, pain-free walking distance, ankle-brachial pressure index and pain scores. No difference was observed in the extent of collateral circulation between pre- and post treatment DSA after separate analysis of clinical responding and non-responding patients (P = 0.92). DSA is not a suited modality for the evaluation of therapeutic angiogenesis.

Abstract 1130: Role Of PI3Kγ For Integrin-dependent Adhesive And Migratory Functions Of Progenitor Cells In Vitro And In Vivo

Endothelial progenitor cells (EPC) are recruited to ischemic regions to improve neovascularization. β1- and β2-integrins play a crucial role for progenitor cell homing to ischemic tissues. Chemokines and their respective G-protein coupled receptors (GPCRs) are involved in the EPC homing to ischemic tissues. The phosphatidylinositol-3-kinase catalytic subunit gamma (PI3Kγ) is the PI3K isoform, which selectively transduces signals from GPCRs. Here, we investigated the role of PI3Kγ for integrin-dependent homing functions of progenitor cells. As assessed by western blot, EPC express the catalytic subunit PI3Kγ. We then studied the role of PI3Kγ for EPC migration. AS-605240 (100 nM), a selective PI3Kγ-inhibitor (Camps M, Nat. Med., 2005), significantly reduced the SDF1- and the IL-8-induced migration and the SDF1-induced transendothelial migration of human EPC. Adhesion is a further essential step during EPC homing to ischemic tissues. In this regard, the PI3Kγ-inhibitor significantly reduced the SDF1-induced adhesion of EPC on HUVEC monolayers by 69 ± 8 % and on ICAM-1, a β2-integrin ligand. However, the PI3Kγ-inhibitor did not affect the SDF1-induced adhesion of EPC on fibronectin, a β1-integrin ligand, suggesting that PI3Kγ in EPC is involved in the regulation of β2-, but not of β 1-integrin-dependent adhesion. In line with these results, inhibition PI3Kγ blocked the SDF1-induced increase of β2-, but not of β1-integrin-affinity in EPC. Beside EPC, the SDF1-induced migration and adhesion on ICAM-1 of murine bone marrow (BM)-derived Lin − progenitor cells from PI3Kγ-deficient mice (PI3Kγ − / − ) were reduced in comparison to wild type (WT) cells. In addition, PI3Kγ-deficiency led to a significant reduction of homing of murine BM-Lin − progenitor cells to ischemic muscles after intravenous infusion in the model of hind limb ischemia in comparison to WT cells (48 ± 8 % inhibition). In conclusion, these data demonstrate that PI3Kγ plays an essential role for the integrin-dependent homing of progenitor cells in vitro and in vivo. The understanding of the molecular mechanisms of progenitor cell homing is essential for the development of new therapeutic strategies in order to improve the efficacy of cell-based therapies in patients with ischemic disorders.

Circulating Endothelial Progenitor Cells Characterization, Function and Relationship with Cardiovascular Risk Factors

Since the first description of putative progenitor endothelial cells mobilized from bone marrow by stimuli like ischemia and cytokines, several studies in animals have confirmed their role in neovascularization of ischemic organs. In ischemic myocardium endothelial progenitor cells can prevent cardiomyocyte apoptosis, reduce remodeling and improve cardiac function. These observations led to the hypothesis of endothelial progenitor cells as possible cell-based therapy in patients by autologous transplantation in ischemic tissue or by improving peripheral circulating numbers with mobilization by cytokines. Early trials, including a randomized one, suggest that the intracoronary autologous bone marrow cell transfer after myocardial infarction exerts at least short term functional benefits. Since endothelial damage and dysfunction play a critical role in atherosclerosis disease, research interest was addressed to evaluate the role of progenitor endothelial cells in vascular endothelial layer maintenance. Opposing to local resident endothelial cells poor proliferation rate, progenitor endothelial cells regenerative capacity, homing and integration into blood vessels have been interpreted as a protective role of these cells in vascular homeostasis. Indeed, the number and function of endothelial progenitor cells relate with the progression of atherosclerosis; the accumulation of cardiovascular risk factors or an increased overall risk are inversely associated with endothelial progenitor cells number and function. Finally, recent studies have shown a role of progenitor cells numbers to predict cardiovascular events, raising endothelial progenitor cells to the podium of novel prognostic biomarker.

Rationale for Designing of Antigen-Specific Immune Therapy Including Dendritic Cell-Based Therapy in Patients with Chronic Hepatitis B Virus Infection

Rationale for Designing of Antigen-Specific Immune Therapy Including Dendritic Cell-Based Therapy in Patients with Chronic Hepatitis B Virus Infection

Blood-Derived Progenitor Cells After Recanalization of Chronic Coronary Artery Occlusions in Humans

See related article, pages 756–762 The first studies to treat patients with acute ST segment elevation myocardial infarction were by Strauer et al and Zeiher et al.1,2 In these studies, percutaneous transluminal coronary angioplasty (PTCA) was used to open the infarct related artery, and bone marrow-derived mononuclear cells or circulating endothelial progenitor cells were injected into the infarct-related arteries.1,2 The cell-based therapy in these 2 initial studies improved coronary blood flow and segmental left ventricular (LV) function in the treated regions. Wollert et al subsequently reproduced the earlier findings in a blinded randomized study, again in patients with acute ST segment elevation myocardial infarcts (MIs).3 These 3 studies were the first to treat patients with acute ST segment elevation MIs after PTCA with cell-based therapy, and each used intracoronary injections in patients who did not have severe heart failure. At the same time that Strauer et al and Zeiher et al were performing their initial studies in Germany (2000–2002), Texas Heart Institute cardiologists, Drs Perin and Willerson and Brazilian cardiologists led by Dr Dohmann in Rio de Janeiro, Brazil, were treating patients with chronic coronary heart disease, prior myocardial infarction, and severe heart failure with transendocardial injections of bone marrow-derived mononuclear cells using electromechanical mapping to identify sites of reversible myocardial injury.4 This was the initial study in the world done with cell-based therapy for patients with severe heart failure with direct transendocardial injections of bone marrow-derived mononuclear cells …

Advances in the use of dendritic cells and new adjuvants for the development of therapeutic vaccines.

The recent advances in immunology and biotechnology have opened new perspectives for the development of immunotherapy strategies against cancer and infectious diseases. The understanding of the pivotal role of dendritic cells in the initiation and regulation of the immune response has led to an ensemble of preclinical studies and pilot clinical trials, which have provided some evidence on the potential advantages of using dendritic cells as cellular adjuvants for the development of therapeutic vaccines against infectious diseases and malignancies. Current research efforts are focused on the definition of optimal protocols for dendritic cell-based therapies in patients. An additional area of emerging importance in the field of immunotherapy is the identification of safe, selective, and more powerful adjuvants, capable not only of enhancing immune protection against pathogens, but also of breaking tolerance against certain tumor-associated antigens, which is the critical issue for the development of cancer vaccines. The recent recognition of the key role of certain cytokines, such as type I interferons, in linking the innate and adaptive immunity through their action on dendritic cells opens new perspectives for using these natural factors as adjuvants for the development of therapeutic vaccines. We review some of the emerging research aspects in immunotherapy, with special attention to the perspectives of using new adjuvants and dendritic cell-based vaccines for the treatment of cancer and infectious diseases.

Beating the odds: a cardiomyocyte cell line at last.

Beating the odds: a cardiomyocyte cell line at last.