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Aims Regenerative therapies based on resident human cardiac progenitor cells (hCPCs) are a promising alternative to medical treatments for patients with myocardial infarction. However, hCPCs are rare in human heart and finding efficient source and proper surface marker for isolation of these cells would make them a good candidate for therapy. Main methods We have isolated 5.34 ∗ 106 ± 2.04 ∗ 105/g viable cells from 35 heart tissue samples of 23 patients with congenital heart disease obtained during their heart surgery along with 6 samples from 3 normal subjects during cardiac biopsy. Key findings According to FACS analysis, younger ages, atrial specimen and disease with increased pulmonary vascular resistance were associated with higher percentage of c-kit+ (CD117) hCPCs. Analysis for other stemness markers revealed increased CD133+ cells in the hearts of patients with congenital heart disease. By using both immune-labeling and PCR, we demonstrated that these cells express key cardiac lineage and endothelial transcription factors and structural proteins during in vitro differentiation and do express stemness transcription factors in undifferentiated state. Another novel datum of potentially relevant interest is their ability in promoting greater myocardial regeneration and better survival in rat model of myocardial infarction following transplantation. Significance Our results could provide evidence for conditions associated with enriched hCPCs in patients with congenital heart disease. Moreover, we showed presence of a significant number of CD133 expressing cardiogenic stem-like cardiac precursors in the heart of patients with congenital heart disease, which could be isolated and stored for future regenerative therapies in these patients.

Background aims Recent studies have proposed that cellular transplantation may have some regenerative and functional efficacy in the treatment of cerebral palsy (CP); however, much remains to be understood regarding its safety, feasibility and efficacy. This study was initiated to evaluate the safety of autologous bone marrow–derived CD133+ cell intrathecal injection. Methods Children (n = 12), aged 4 to 12 years, who were diagnosed with different types of CP underwent BM aspiration. CD133+ cells were enriched from the BM samples and intrathecally injected. The Gross Motor Function Measure (GMFM-66), Gross Motor Function Classification System (GMFCS), UK FIM+FAM, Functional Independence Measure (FIM) and Functional Assessment Measure (FAM) were assessed at baseline and 6 months after the procedure. Patients' ability to balance was measured by the Berg Balance Scale (BBS), and severity of spasticity was evaluated by the Modified Ashworth Scale. Magnetic resonance imaging was done at baseline and 6 months after therapy. This study was registered in ClinicalTrials.gov ( NCT01404663 ). Results There were no adverse events detected by clinical and laboratory tests or imaging studies, with the exception of a seizure in 1 patient. A significant improvement was observed 6 months after cell transplantation versus baseline according to GMFM, GMFCS, FIM+FAM, Ashworth Scale, and BBS outcomes. Conclusions Subarachnoid injection of CD133-positive enriched bone marrow progenitor cells in children with CP is a safe approach. The results suggest a possible short-term improvement in neurological function.

Cardiovascular diseases hold the highest mortality rate among other illnesses which reveals the significance of current limitations in common therapies. Three-dimensional (3D) scaffolds have been utilized as potential therapies for treating heart failure following myocardial infarction (MI). In particular, native tissues have numerous properties that make them potentially useful scaffolding materials for recreating the native cardiac extracellular matrix (ECM). Here, we have developed a pericardium-derived scaffold that mimics the natural myocardial extracellular environment and investigated its properties for cardiac tissue engineering. Human pericardium membranes (PMs) were decellularized to yield 3D macroporous pericardium scaffolds (PSs) with well-defined architecture and interconnected pores. PSs enabled human Sca-1(+) cardiac progenitor cells (CPCs) to migrate, survive, proliferate and differentiate at higher rates compared with decellularized pericardium membranes (DPMs) and collagen scaffolds (COLs). Interestingly, histological examination of subcutaneous transplanted scaffolds after one month revealed low immunological response, enhanced angiogenesis and cardiomyocyte differentiation in PSs compared to DPMs and COLs. This research demonstrates the feasibility of fabricating 3D porous scaffolds from native ECMs and suggests the therapeutic potential of CPC-seeded PSs in the treatment of ischemic heart diseases.

In this study, physical and biological features of the novel three-dimensional cell-loaded gelatin (G)/chitosan (CS) scaffolds fabricated via combining salt-leaching and lyophilization technique is evaluated. To fabricate these scaffolds, CS and G solutions were blended at different ratios and the influence of G/CS ratio on physical and biological properties of the scaffolds were studied. The properties of porous structure, such as microstructure, porosity, mean pore size, phosphate buffer saline solution absorption, mechanical properties as well as biocompatibility were evaluated. The in vitro assays showed excellent cell attachment and proliferation on scaffolds with G/CS ratio of 80/20. The results showed that the amount of G has a significant effect on attachment, growth, and proliferation of fibroblast cells on the scaffolds. In vivo assessment showed that treatment with human dermal fibroblast cell loaded scaffolds significantly accelerated wounds healing in rat compared with the control groups. The biological investigation on these scaffolds proves that they have a great potential for using in skin tissue engineering.

Contains fulltext : 118796.pdf (Publisher’s version ) (Open Access) Bone marrow-derived mesenchymal stem cells (MSCs) have the capacity to regenerate renal tubule epithelia and repair renal function without fusing with resident tubular cells. The goal of the present project was to investigate the role of MSCs secreted cytokines on tubule cell viability and regeneration after a toxic insult, using a conditionally immortalized human proximal tubule epithelial cell (ciPTEC) line. Gentamicin was used to induce nephrotoxicity, and cell viability and migration were studied in absence and presence of human MSC-conditioned medium (hMSC-CM) i.e. medium containing soluble factors produced and secreted by MSCs. Exposure of ciPTEC to 0-3000mug/ml gentamicin for 24h caused a significant dose-dependent increase in cell death. We further demonstrated that the nephrotoxic effect of 2000mug/ml gentamicin was recovered partially by exposing cells to hMSC-CM. Moreover, exposure of ciPTEC to gentamicin (1500-3000mug/ml) for 7 days completely attenuated the migratory capacity of the cells. In addition, following scrape-wounding, cell migration of both untreated and gentamicin-exposed cells was increased in the presence of hMSC-CM, as compared to exposures to normal medium, indicating improved cell recovery. Our data suggest that cytokines secreted by MSCs stimulate renal tubule cell regeneration after nephrotoxicity.

Despite its numerous limitations, liver transplants are the only definite cure for end-stage liver disease. Various stem cell populations may contribute to liver regeneration, of which there is accumulating evidence of the contribution of mesenchymal stem cells (MSCs). This study examines the hypothesis that repeated infusions of human bone marrow-derived MSCs (hBMMSCs)can improve liver injury in an experimental model. MSCs were intravenously transplanted into immunosuppressed mice with carbon tetrachloride (CCl(4))-induced liver fibrosis. Transplanting 3x10(6) MSCs in three divided doses improved survival,liver fibrosis and necrosis compared with injection of the same number of MSCs in a single dose. This was accompanied by increased influence on the expression of the fibrogenic/fibrolytic related genes Col1a1, Timp1 and Mmp13 in the repeated transplant group. Repeat administration of MSCs was three times more effective in homing of PKH-tagged transplanted cells 3 weeks post-transplant compared with the single transplant group. The benefits of repeated transplants may be of considerable significance in clinical trials on liver failure.

BACKGROUND Several studies have demonstrated the derivation of multi- or pluripotent stem cells from testicular cells of both newborn and adult mice by a spontaneous conversion process, when these cells are cultured in vitro for an extended time. To obtain a better and robust derivation, we have attempted to identify small molecules (SMs) that induce reprogramming of testicular cells in culture into germline-derived pluripotent stem cells (gPSCs). METHODS We tested several SMs based on previous reports that have shown enhancement of establishment of induced pluripotent stem cells or embryonic stem cells (ESCs) on mouse NMRI (outbred strain) and C57BL/6 (inbred strain) testicular cells. After appearance of ESC-like colonies at Day 6, they were passaged on mitotically arrested mouse embryonic fibroblasts in mouse ESC medium in the absence or presence of SMs up to Day 14. The generated cells were characterized using a variety of experimental approaches. RESULTS The application of several SMs involved in pluripotent reprogramming led to the discovery that CHIR99021 (CHIR), a glycogen synthase kinase-3 (GSK-3) inhibitor, promotes efficient derivation of gPSCs from neonatal mouse NMRI and C57BL/6 testes. The pluripotency of the generated cell lines has been confirmed by in vitro spontaneous and direct differentiation toward cardiac and neural lineages, and formation of chimeras after injection of gPSCs into blastocysts. We have shown that the generated gPSCs could be maintained and expanded under chemically defined serum and feeder-free conditions by inhibition of both the extracellular signal-regulated kinases (Erk1/2) and GSK-3. CONCLUSIONS To our knowledge, this is the first report of a simple and efficient protocol to reprogram gPSCs from testicular cells solely by inhibition of GSK-3 in two strains of mice with different genetic backgrounds. Additionally, this brings us closer to eliminating the need for genetic modification in pluripotent reprogramming. Future studies will determine whether the inhibition of GSK-3 could affect the generation of naive gPSCs lines in other mammals.

BACKGROUND During the resent years there has been interest in using bone marrow stem cells to treat liver cirrhosis. However, there is a potential concern for malignant transformation after stem cell therapy. The aim of this study was to evaluate the development of hepatocellular carcinoma (HCC) after autologous bone marrow stem cell transplantation for liver cirrhosis. METHODS All the patients who underwent autologous stem cell transplantation for liver cirrhosis between 2005 and 2011 at our center were enrolled. Cellular infusion was made through peripheral vein, portal vein, or hepatic artery.The patients were invited to undergo screening for hepatocellular carcinoma. The screening was made with ultrasonography and alpha-feto protein (AFP) measurement. RESULTS Thirty two patients (18 males) were included in the study. Mean age of patients was 45.7 years. Fifteen patients (47%) received mesenchymal stem cell (MSC), 9 (28%) received bone marrow mononuclear cells, 5 (16%) were given CD 133-positive bone marrow cells, and 3 (9%) patients received CD 34-positive bone marrow cells. Mean duration of follow up was 20.5months. Mean serum level of AFP was 2.8 ng/ml at baseline and 3.4ng/ml at the end of follow up (p= 0.3). One patient was found to have hepatocellular carcinoma three months after infusion of bone marrow mononuclear cells. The incidence rate for HCC was 1.8 cases per 100 person-years in this study. CONCLUSION Autologous bone marrow stem cell infusion does not appear to increase the risk of hepatocellular carcinoma. The incidence rate of HCC in this study is comparable or even less than the reported rates of HCC in cohort studies of cirrhotic patients.

The implantation of a CD133+ bone marrow cell population into an ischemic myocardium has emerged as a promising therapeutic modality for myocardial regeneration and restoration of ventricular contractility. While previous studies have documented the short-term safety and efficacy of CD133+ cell transplantation in patients with acute myocardial infarction, there are few reports of long-term follow-up results. Here, we present the results of long-term follow-up of our acute myocardial infarction patients who were treated with intramyocardial injection of CD133+ cells after coronary bypass graft.After five years, 13 patients in the cell transplantation group and 5 patients in the control group underwent safety and efficacy investigations by New York Heart Association classification and two-dimensional echocardiography (2D echo).During the five-year study period, no major cardiac adverse events were reported among patients who received CD133+ stem cells. Regarding efficiency, we observed no statistically significant treatment effects for the echocardiographic parameters [left ventricular end-diastolic and end-systolic volumes, and resting ejection fraction] measured during the follow-up period. However, detailed analysis of regional wall motion revealed an improvement in the Wall Motion Score Index from baseline to the six month follow-up, which was maintained during the follow-up period.Taken together, the long-term results of the present study indicate that transplantation of CD133+ is a safe and feasible procedure; however, we could not show any major benefits in our patients. Thus, this issue needs to be addressed by conducting other studies with more patients.

One of the fields of medicine that has raised the most expectations in Iran is cell therapy, using somatic or stem cells. The word “cell therapy” refers a series of procedures, which are used to separate and transplant cells in target tissues. However, in the absence of a current consensus on a approved protocol to isolation and identify suitable cells, the most methods in this field are under research yet. Royan Institute, as a leading center in stem cell research, in Iran, simultaneous with global research and increasing the knowledge about stem cells, the first Royan clinical trial in cell therapy field was done in 2004, which was designed and implemented for application of stem cells in patients with recent heart attack. During implementation of this project, at least three other projects were added to the list of Royan institute clinical trials. Two years later, Royan institute started to established GMP facilities for cell culture. By the end of year 2008, increasing number of clinical trials from 4 to 10 studies and termination of investigating stages of using Melanocytes for treatment of vitilligo disease and Limbal stem cells culture for using in patients with Limbal disease, led to establishment of a center for providing medical services to the patients. Now Royan institute in Regenerative department are doing more than 20 NIH registered clinical trials and there are some result in heart, bone, cartilage, limbal, liver and skin field, which will be presented in this lecture.

The use of different sources of stem cells including embryonic and mesenchymal stem cells is a novel therapy for diabetic’s patients. However the efficiency of differentiation is not enough to complete treatment. An important point in the induction of stem cells into IPCs in vitro is the role of the pancreatic niche (which includes the stromal and epithelial niche). It can physically contact to adjacent cells and influence stem cell behavior via close range signaling. In this respect, we hypnotized that Pancreatic Stromal Cell (PSC) as a fundamental factor of the stromal niche may have an effective role in the generation IPCs (i.e, the efficiency of differentiation and function of newlyformed β-cells) in vitro. Therefore in this study, MSCs derived from umbilical cord (UC-MSCs) vain and bone marrow (BM-MSCs) was selected to differentiate into IPCs in co-culture with rat PSCs. Our results have demonstrated that only BM-MSCs were able to differentiate into IPCs. Cells in Islet-like clusters with (out) co-cultured with rat pancreatic stromal cells, produced insulin and C-peptide and released them to culture medium at the end of the induction protocol; however they did not respond to glucose challenges very well. The presence of rat pancreatic stromal cells, up-regulated the expressions of insulin, Glut2, and Nkx2.2 were at the mRNA level in IPCs. These results suggested that rat PSCs possibly affect MSCs differentiation into IPCs by increasing the number of immature β-cells.

We describe a new, efficient protocol that involves the serial addition of noggin, basic fibroblast growth factor (bFGF), retinoic acid, and sonic hedgehog (Shh) for the differentiation of human induced pluripotent stem cells (hiPSC) to retinal pigmented epithelium (RPE) in a serum- and feeder-free adherent condition. hiPSC-RPE cells exhibited RPE morphology and specific molecular markers. Additionally, several hiPSC lines were generated from retinal-specific patients with Leber's congenital amaurosis, Usher syndrome, two patients with retinitis pigmentosa, and a patient with Leber's hereditary optic neuropathy. The RPE cells generated from these disease-specific hiPSCs expressed specific markers by the same RPE lineage-directed differentiation protocol. These findings indicate a new short-term, simple, and efficient protocol for differentiation of hiPSCs to RPE cells. Such specific retinal disease-specific hiPSCs offer an unprecedented opportunity to recapitulate normal and pathologic formation of human retinal cells in vitro, thereby enabling pharmaceutical screening, and potentially autologous cell replacement therapies for retinal diseases.

Early clinical studies have suggested that administration of granulocyte-colony stimulating factor (G-CSF) may improve the clinical condition of patients suffering from myocardial infarction (MI).This prospective, randomized, double-blind, placebo-controlled single-centre trial aims to assess the safety and clinical efficacy of G-CSF administration in patients with subacute MI and impaired LV function undergoing delayed primary percutaneous coronary intervention (PCI).A total of 16 patients (13 men, mean age 51 years) with subacute ST-segment elevation MI and a left ventricular (LV) ejection fraction (EF) of less than 45% at baseline who underwent late revascularization, were included in the study. Patients were randomized in a double-blind fashion to receive either G-CSF (at a dose of 10 microg/kg body weight) or placebo for five consecutive days. End points consisted of assessment of safety parameters as well as changes of global and regional myocardial function from baseline until six months following PCI.G-CSF administration resulted in a significant mobilization of different cell populations (four-fold increase in WBC count and a six-fold increase in CD34+ cells). G-CSF treatment was well tolerated in most patients and no major adverse cardiac events or severe G-CSF-related side effects were identified during hospitalization and at follow-up. No significant differences were observed between the G-CSF and placebo groups regarding global and regional myocardial function parameters.G-CSF administration is safe, but not effective, in improving impaired LV functional parameters in patients with subacute MI who had an impaired baseline EF of less than 45%.

Despite the suitability of a mouse model for preclinical investigations; little is known regarding mesenchymal stem cells derived from murine amniotic fluid. This is the subject of the present study. Amniotic fluid was collected from NMRI mice during the second weeks of pregnancy and plated. The cells that adhered to the culture surfaces were propagated with three successive subcultures and then characterized. To determine the differentiation potential, the cells were cultivated under osteogenic, adipogenic, and chondrogenic conditions, and followed by specific staining and RT-PCR analysis for differentiation. The proliferative potential of the cells were measured with clonogenic assays, population doubling time and number and by growth curve plotting. Cellular aging was investigated with the senescence-associated ß-galactosidase staining method.The amniotic fluid primary cell culture was composed of round flattened and fibroblastic cells. The latter dominated the culture after several passages. Successful tripotent differentiation of the isolated cells into bone, cartilage and adipose cells were indicative of their mesenchymal stem cells nature. The isolated cells appeared to be relatively proliferative cells as confirmed by the population doubling time value which was equal to about 69 hours. Furthermore, the cells were relatively clonogenic and they tended to initiate proliferation immediately after plating (there was no lag phase in their growth curve). ß-galactosidase positive cells were first observed at passage 3 and increased in number with subsequent passages.Collectively it was concluded that murine amniotic fluid contained mesenchymal stem cells with relatively high proliferation property and typical tripotent differentiation potential.

Quantum dots (QDs), as new and promising fluorescent probes, hold great potential in long term non-invasive bio-imaging, however there are many uncovered issues regarding their competency. In the present study, different QDs (525, 585 and 800 nm) were used to label CD133, CD34, CD14 and mesenchymal stem cells (MSCs) using positively charged peptides. Results demonstrated highly efficient internalization with the possible involvement of macropinocytosis. As indicated by LDH release and the TUNEL assay, no measurable effects on cell viability were detected at a concentration of 10 nM. QDs did not have any deleterious effects on normal cell functionality where both labeled CD133(+) cells and MSCs remarkably differentiated along multiple lineages with the use of the colony forming assay and adipo/osteo induction, respectively. Our results regarding QD maintenance revealed that these nano-particles are not properly stable and various excretion times have been observed depending on particle size and cell type. In vitro co-culture system and transplantation of labeled cells to an animal model showed that QDs leaked out from labeled cells and the released nano-particles were able to re-enter adjacent cells over time. These data suggest that before any utilization of QDs in bio-imaging and related applications, an efficient intra-cellular delivery technique should be considered to preserve QDs for a prolonged time as well as eliminating their leakage.

Cirrhosis, the end stage of progressive hepatic fibrosis, is characterized by distortion of the hepatic architecture and the formation of regenerative nodules. Liver transplantation is one of the few available therapies for such patients. However, due to a severe shortage of organ donors, surgical complications, transplant rejection and the high cost of this procedure much interest has focused on research to find new treatment modalities for this disease. There is accumulating evidence for the contribution of bone marrow stem cells to participate in liver regeneration.Here we report on six patients with end stage liver disease who were subjected to intraportal administration of autologous bone marrow-derived CD133(+) in comparison to mononuclear cells in short-term (6 months) and long-term (24 months) follow up.There were no adverse effects in any of the patients during the short- and long-term follow up period. Moreover, there were no significant alterations of liver function parameters, liver enzymes, serum albumin, creatinine, serum bilirubin and/or liver volume after transplantation of both types of autologous cells in these patients.Our study has shown both the safety and feasibility of this type of liver cell therapy and may be a bridge to liver transplantation. The trial was registered with NIH clinical trials (www.clinicaltrials.gov) as identifier: NCT00713934.

The availability of disease-specific induced pluripotent stem cells (iPSCs) offers a unique opportunity for studying and modeling the effects of specific gene defects on human liver development in vitro and for testing small molecules or other potential therapies for relevant liver disorders. Here we report, for the first time, the derivation of iPSCs by the retroviral transduction of Yamanaka’s factors in serum and feeder-free culture conditions from liver-specific patients with tyrosinemia, glycogen storage disease, progressive familial hereditary cholestasis, and two siblings with Crigler-Najjar syndrome. Furthermore, they were differentiated into functional hepatocyte-like cells efficiently. These iPSCs possessed properties of human embryonic stem cells (hESCs) and were successfully differentiated into three lineages that resembled hESC morphology, passaging, surface and pluripotency markers, normal karyotype, DNA methylation, and differentiation. The hepatic lineage-directed differentiation showed that the iPSC-derived hepatic cells expressed hepatocyte-specific markers. Their functionality was confirmed by glycogen and lipid storage activity, secretion of albumin, alpha-fetoprotein, and urea, CYP450 metabolic activity, as well as LDL and indocyanin green uptake. Our results provide proof of principal that human liver-disease specific iPSCs present an exciting potential venue toward cell-based therapeutics, drug metabolism, human liver development and disease models for liver failure disorders.

Human embryonic stem cell (hESC)-derived hepatocytes provide a promising unlimited resource for the treatment of liver disease. However, current protocols for the generation of mature and functional hepatocytes are inefficient. Therefore, in order to better differentiate and maintain the function of differentiating hESCs, we have hypothesized that hESCs undergo better differentiation into hepatocyte-like cells (HLCs) when induced on three-dimensional nanofibrillar surfaces. We have demonstrated that, during stepwise differentiation of induction, the markers of hepatic lineage expressed and finally lead to the generation of functional mature cells. In the presence of an ultraweb nanofiber, HLCs produced lower AFP, greater urea, glycogen storage, metabolic PROD activity, uptake of LDL and organic anion ICG, all of which are indicative of the differentiation of HLCs. These results show that topographically treated hESCs at the nano level have a distinct hepatic functionality profile which has implications for cell therapies.

The recent discovery of genomic reprogramming of human somatic cells to an embryonic stem (ES) cell-like pluripotent state provides a unique opportunity for stem cell research. The reprogrammed cells, named as induced pluripotent stem (iPS) cells, possess many of the properties of ES cells and represent one of the most promising sources of patient-specific cells for use in disease model, development of pharmacology and toxicology, screening teratogens, and regenerative medicine. Here we describe the detailed methods for the generation of undifferentiated human iPS (hiPS) cells in feeder layer- and serum-free conditions. This system eliminates direct contact of stem cells with MEFs and reduces use of unknown serum factors that may have undesired activities and enables consistency in large-scale and long-term expansion of undifferentiated hiPS cells. Our findings greatly simplify the method for induction of pluripotency and bring it one step closer to clinical applications. Moreover, the established hiPS cells showed chromosomal stability during long-term culture.

Bombay phenotype is one of the rare phenotypes in the ABO blood group system that fails to express ABH antigens on red blood cells. Nonsense or missense mutations in fucosyltransfrase1 (FUT1) and fucosyltransfrase2 (FUT2) genes are known to create this phenotype. This blood group is compatible with all other blood groups as a donor, as it does not express the H antigen on the red blood cells. In this study, we describe the establishment of human induced pluripotent stem cells (iPSCs) from the dermal fibroblasts of a Bombay blood-type individual by the ectopic expression of established transcription factors Klf4, Oct4, Sox2, and c-Myc. Sequence analyses of fibroblasts and iPSCs revealed a nonsense mutation 826C to T (276 Gln to Ter) in the FUT1 gene and a missense mutation 739G to A (247 Gly to Ser) in the FUT2 gene in the Bombay phenotype under study. The established iPSCs resemble human embryonic stem cells in morphology, passaging, surface and pluripotency markers, normal karyotype, gene expression, DNA methylation of critical pluripotency genes, and in-vitro differentiation. The directed differentiation of the iPSCs into hematopoietic lineage cells displayed increased expression of the hematopoietic lineage markers such as CD34, CD133, RUNX1, KDR, alpha-globulin, and gamma-globulin. Such specific stem cells provide an unprecedented opportunity to produce a universal blood group donor, in-vitro, thus enabling cellular replacement therapies, once the safety issue is resolved.

Although human induced pluripotent stem cells (hiPSCs) hold great promise as a source of differentiated cells for vast therapeutic implications, many obstacles still need to be surmounted before this can become a reality. One obstacle, a robust feeder- and serum-free system to generate and expand hiPSCs in culture is still unavailable. Here, for the first time, we describe a novel establishment and maintenance culture technique that uses human dermal fibroblasts to generate hiPSCs by introducing four factors, Klf4, Oct4, Sox2, and c-Myc under serum- and feeder-independent conditions. We have used a serum replacement product, conditioned medium (CM), or feeder-free medium (FFM) supplemented with high elevated basic-fibroblast growth factor in the absence or presence of Matrigel. Our FFM system in the presence of Matrigel enhanced the efficiency of alkaline phosphatase-positive colonies at a frequency at least 10-fold greater than the conventional method on feeder cells. The established hiPSCs are similar to human embryonic stem cells in many aspects including morphology, passaging, surface and pluripotency markers, normal karyotype, gene expression, ultrastructure, and in vitro differentiation. Such hiPSCs could be useful particularly in the context of in vitro disease modeling, pharmaceutical screening and in cellular replacement therapies once the safety issues have been overcome.

The recent discovery of genomic reprogramming of human somatic cells to an embryonic stem (ES) cell-like pluripotent state provides a unique opportunity for stem cell research. The reprogrammed cells, named as induced pluripotent stem (iPS) cells, possess many of the properties of ES cells and represent one of the most promising sources of patient-specific cells for use in disease model, development of pharmacology and toxicology, screening teratogens, and regenerative medicine. Here we describe the detailed methods for the generation of undifferentiated human iPS (hiPS) cells in feeder layer- and serum-free conditions. This system eliminates direct contact of stem cells with MEFs and reduces use of unknown serum factors that may have undesired activities and enables consistency in large-scale and long-term expansion of undifferentiated hiPS cells. Our findings greatly simplify the method for induction of pluripotency and bring it one step closer to clinical applications. Moreover, the established hiPS cells showed chromosomal stability during long-term culture.

GVHD is a major complication in allogeneic SCT. Available GVHD models are mainly based on radiotherapy-conditioning and/or immune deficient mice. GVHD models based on chemotherapy-based regimens remain poorly studied, despite 50% of all transplantations being chemotherapy based. Our aim was to develop a GVHD model using chemotherapy as conditioning. Female BALB/c (H-2Kd) were conditioned with BU-CY and transplanted with 2 x 10(7) BM and 3 x 10(7) spleen cells from either C57BL/6 (H-2 Kb) mice (allogeneic setting) or from male BALB/c to serve as a control group for regimen-related toxicity and engraftment. GVHD manifestations and histopathological changes were evaluated. Chimerism and donor T cells presence in skin, intestine and liver were studied using FACS-, FISH analysis and immunohistochemistry. Allogeneic transplanted mice developed lethal GVHD starting from day+7 with both histological and clinical signs. Donor T cells accumulated in recipient skin and intestine with GVHD progression. BM-failure, apoptosis and T-lymphocyte infiltration into target organs were significantly higher in allogeneic when compared with the syngeneic group. No toxicity or GVHD signs were observed in the syngeneic setting. We report a mouse model of GVHD using BU-CY conditioning that represents the most common myeloablative-conditioning regimen in clinical SCT. This model can be utilized to study the role of conditioning on mechanisms underlying GVHD.

Dendritic cells (DCs) are the most potent antigen-presenting cells (APC) of the immune system, and are critically involved in initiation of immune responses in autoimmune diseases. They can modulate the nature of immune responses to stimulatory or tolerogenic fashion. Previous studies have demonstrated that the administration route of DCs is an important variable in eliciting anti-tumor immunity. In this study we used experimental autoimmune encephalomyelitis (EAE) as an animal model of multiple sclerosis to compare different protocols of DC delivery in autoimmunity or tolerance induction. Dendritic cells were generated from bone marrow cells of C57BL/6 mice by culturing in the presence of GM-CSF and IL-4 for 7 days, followed by 2 days culture with TNF-alpha. The obtained DCs were pulsed in vitro with myelin oligodendrocyte glycoprotein (MOG) peptide and injected (5 x 10(5) cells/mouse) via the intravenous (i.v.), intraperitoneal (i.p.) or subcutaneous (s.c.) route into female C57BL/6 mice. In some instances pertussis toxin was also injected zero and 48 hours after DC injection. After follow up of the mice pretreated in this way for 4 weeks, in the i.v. group in which no clinical signs of EAE occurred, the mice were immunized with MOG peptide for EAE induction via the common method and the results were compared with mice that were not pre-immunized. Only after three s.c. DC injections with pertussis toxin, the mice showed mild clinical signs of EAE, whereas mice given i.v. or i.p. injections with or without pertussis toxin failed to develop EAE after 4 weeks. Induction of EAE via the common method after three injections of TNF-alpha treated DCs, in i.v. injected groups showed no protection from EAE. It seems that several factors influence the tolerance versus immunity induction by DCs. Our results showed that the administration route of DCs is one of the pivotal factors in DC-based induction of autoimmune diseases.

Introduction: Arsenic trioxide is effective and approved for treatment of relapsed or refractory acute promyelocytic leukemia (APL) cases resistant to all-trans retinoic acid (ATRA), but its effect on new cases of APL is not clear. Materials and methods: We studied 111 patients with APL. Arsenic trioxide was infused at 0.15 mg/kg daily dose, until complete remission was achieved. Then, after 28 days of rest, arsenic trioxide was infused daily for 28 days as consolidation therapy. We studied minimal residual disease (MRD) by semi-sensitive reverse transcription polymerase chain reaction (RT–PCR) on peripheral blood samples. Results: Complete remission was observed in 95 patients (85.6%). With the median (range) follow-up period of 16.5 (1–57) months, 1- and 2-year disease-free survival was 88.3% and 63.7%, respectively; 24 patients relapsed, 19 of whom achieved a second complete remission, again by arsenic trioxide. Third and fourth remissions were seen in some relapsed patients, again by arsenic trioxide. For patients in complete remission, 1- and 3-year survival was 95.5% and 87.6%, respectively. MRD was positive in four (8.3%) out of 48 cases during 1 year after remission induction; three of them relapsed clinically. Conclusions: Arsenic trioxide is effective as first-line treatment for APL. Results of arsenic trioxide combination therapy with chemotherapy/ATRA requires further study.

devoid of cellular and nuclear material while extracellular matrix remained intact Native and decellularized arteries were digested using Proteinase K and DNA content was measured. For the proteomic analysis the umbilical arteries were snap frozen in liquid nitrogen and homogenized. The protein content was measured using Bradford assay and analyzed by 2D Electrophoresis. Protein spots were excised manually and tryptic digestion and Peptide Mass Fingerprinting was performed. Decellularized patches (3x3 mm) of umbilical artery were seeded with 10,000 MSCs-RFP+ per patch, incubated for 2 weeks at 37o C and 5% CO2 and no cytotoxic effect was observed. Conclusion: Both decellularization protocols effectively removed the cellular material while the ECM remained intact and supported MSCs seeding.Future studies are warranted to elucidate the specific effects of altered structuree function relationships on the overall fate of decellularized umbilical arteries.

Despite its numerous limitations, liver transplants are the only definite cure for end-stage liver disease. Various stem cell populations may contribute to liver regeneration, of which there is accumulating evidence of the contribution of mesenchymal stem cells (MSCs). This study examines the hypothesis that repeated infusions of human bone marrow-derived MSCs (hBMMSCs)can improve liver injury in an experimental model. MSCs were intravenously transplanted into immunosuppressed mice with carbon tetrachloride (CCl(4))-induced liver fibrosis. Transplanting 3x10(6) MSCs in three divided doses improved survival,liver fibrosis and necrosis compared with injection of the same number of MSCs in a single dose. This was accompanied by increased influence on the expression of the fibrogenic/fibrolytic related genes Col1a1, Timp1 and Mmp13 in the repeated transplant group. Repeat administration of MSCs was three times more effective in homing of PKH-tagged transplanted cells 3 weeks post-transplant compared with the single transplant group. The benefits of repeated transplants may be of considerable significance in clinical trials on liver failure.

Background: Transplantation related complications such as graft versus host disease (GVHD) are limiting factors for allogeneic haematopoietic stem cell transplantation (HSCT). The majority of mice models of GVHD are based on the use of radiotherapy as a conditioning regimen. However, these models may not explain mechanisms of HSCT related complications following chemotherapy-based conditioning regimen. Aims: The aim of this study was establishment of a mice model of GVHD using the chemotherapy as conditioning regimen. Methods: Recipient female BALB/c (H-2Kd) were conditioned using busulfan (Bu) in total dose of 80 or 100 mg/kg followed by cyclophosphamide (Cy) in total dose of 200 or 300 mg/kg. Twenty millions of bone marrow (BM) cells and 30×106 spleen cells of male C57BL/6 (H-2Kb) were injected into the recipient mice in allogeneic setting. As a control, syngeneic HSCT using female BALB/c as recipients and donors and the same conditioning regimen and cell doses as in allogeneic setting was used. Acute GVHD manifestations and histo-pathological changes in skin, liver and intestine were evaluated at different time points after BMT. The chimerism and tissue mapping were studied by FACS, immunohistochemistry and FISH analysis. Affected skin was examined by FACS analysis to find donor T cells. Cytokines level were measured by using luminex assay. Results: Infusion of 20×106 BM cells and 30×106 spleen cells from C57BL/6 mice to BALB/c mice conditioned with 80 or 100mg/kg Bu plus 200mg/kg Cy induced lethal acute GVHD between days 5–7 post transplantation. Histological and clinical signs of GVHD were found in 85% and 100% of the allogeneic transplanted mice based on the intensity of conditioning. About 35% of mice in allogeneic group died due to GVHD progression. The number of donor T cell in the recipient skin increased with GVHD progression and was correlated to the level of chimerism in the spleen but not in the BM. CD3+ CD8+ T cells infiltration and apoptosis were found in the skin, intestine and liver of mice suffering from GVHD. None of the syngeneic transplanted mice died or developed any sign of GVHD even in long term follow up, and CD3+CD8+ T cells were absent in their tissue samples. Increasing the dose of Cy in conditioning regimen in allogeneic transplanted mice increased mortality of animals. Conclusion: We have established a new mouse model of acute GVHD using chemotherapy based conditioning. This model can be utilized to study the basic mechanisms underlying GVHD triggered by cytostatics used in the conditioning regimen and affecting different cell sub-populations and cytokine storm. Figure Figure Figure Figure

Purpose: Arsenic Trioxide approved for treatment of relapsed or refractory APL to ATRA. We studied the effects of Arsenic Trioxide as first line treatment of new cases of APL and their follow up. Material and methods: we studied 73 new cases of APL diagnosed by morphologic criteria and confirmed by cytogenetic, RT-PCR for PML/RARA and/or FISH and followed patients for MRD by sensitive nested RT-PCR. Our patients were 30 males and 43 females with median age 30+/− 12. Patients treated by infusion of 0.15mg/kg/d of Arsenic Trioxide to complete remission by morphologic criteria or till day +60. In patients who complete remission achieved, after 28 days rest, again we began Arsenic Trioxide 0.15mg/kg/d for 28 days as consolidation. Results: complete remission were achieved in 66 patients( 90.4%) and 7 early mortality. Median time to complete remission was 30+/−6.4 days. Most common cause of mortality was APL maturation syndrome ( 4 cases) Most common toxicities during induction phase were, APL maturation syndrome (10 cases), serositis(6 cases) and hepatotoxicity (19 cases). 63 cases(86.3%) are alive with a median follow up of 17+/−12.65 months. 14 relapses observed in our patients and complete remission achieved with re-treatment by Arsenic trioxide in 11 of them. Also we could control 3 fatal bleeding by infusion of activated factor 7(NovosevenÒ) which stopped hemorrhage . One year and two/three years survival of patients were 86% and 84%. Most common cause of death was APL maturation syndrome in 4 patients and relapse in 3 cases.Conclusion: Arsenic Trioxide is acceptable as first line treatment of APL and its result is comparable to ATRA with chemotherapy.

Vascular injury and destruction of endothelial cells (ECs) are the early events in scleroderma (SSc) patients. This study aims to investigate the therapeutic potential of human-induced pluripotent stem cell-derived ECs (hiPSC-ECs) to treat SSc. We have assessed the functional differentiation of hiPSC-ECs and compared them with human embryonic stem cell-derived ECs (hESC-ECs) by a variety of in vitro experimental approaches. Additionally, we evaluated the therapeutic potential of hiPSC-ECs in a bleomycin-induced SSc mouse model. Our results demonstrated that hiPSC-ECs and hESC-ECs showed similar maximum expressions of FLK1 (early EC marker) at day five during differentiation. After sorting and culturing, the FLK1-positive cells exhibited spindle and subsequent endothelial cobblestone morphology in EGM2 medium. The hESC-ECs and hiPSC-ECs also expressed late EC markers CD31 (68% and 75%), CD144 (50% and 61%), CD146 (46% and 61%), and DiI-labeled acetylated low-density lipoprotein (DiI-ac-LDL) uptake (55% and 63%), respectively. They additionally formed capillary-like structures on Matrigel. Analyses of the transplantation of sorted CD31-positive hiPSC-ECs into the bleomycin-induced SSc mouse model demonstrated that these cells participate in recovery of the damaged vessels. There was a reduction in collagen content; the number of total and degranulated mast cells returned to their normal state, and bleomycin-induced wounds as well as skin fibrosis improved four weeks after transplantation of hiPSC-ECs. Our findings have shown that the differentiation process from hESCs and hiPSCs to vascular cell components is similar. Additionally, this is the first study to determine the therapeutic potential of vascular cells from hiPSCs in the treatment of an SSc model. In the future, with further validation, these may be used as an appropriate source for the treatment of SSc patients.