Kang Hsi Wu

Effective treatment of severe steroid-resistant acute graft-versus-host disease with umbilical cord-derived mesenchymal stem cells

Background. Severe steroid-resistant acute graft-versus-host disease (aGVHD) is associated with high mortality. Bone marrow-derived mesenchymal stem cells (BMMSC) have been found to be immunosuppressive, and intravenous infusion of BMMSC is an effective therapy for steroid-resistant aGVHD. However, acquiring BMMSC requires an invasive procedure. Methods. We compared umbilical cord-derived mesenchymal stem cells (UCMSC) and BMMSC for morphology, surface markers expression, differentiation, proliferative potential, and their suppressive effects on peripheral blood mononuclear cell proliferation. After institutional review board approved, we intravenously infused ex vivo expanded third-party UCMSC into two patients with severe steroid-resistant aGVHD. Adverse effects and patient responses of UCMSC were monitored. All procedures for UCMSC processing complied with current good tissue practice requirements. Results. We found that UCMSC had superior proliferative potential and more suppressive effects on peripheral blood mononuclear cell proliferation compared with BMMSC. The aGVHD improved dramatically after each of four infusions of UCMSC into the two patients. No adverse effects were noted. Both patients are doing well now. Conclusions. Considering that acquiring UCMSC is noninvasive, these cells would appear to be the ideal candidates for clinical cell-based therapies. This is the first report of UCMSC in a human clinical application, and this procedure seems both feasible and safe. These findings suggested that UCMSC were effective for treating aGVHD.

Combined therapy with deferiprone and desferrioxamine successfully regresses severe heart failure in patients with β-thalassemia major

Cardiac complications caused by iron deposition are major causes of death in patients with β-thalassemia major. Deferiprone (L1) was found to have greater efficacy at depleting myocardial iron than desferrioxamine (DFX). Furthermore, combined therapy with L1 and DFX produced an additive or synergistic iron chelating effect. We report the successful treatment of severe heart failure in two patients with β-thalassemia major with the combined therapy. Magnetic resonance images showed a marked recovery of signal intensity in the heart, indicating a significant reduction of iron load in the heart. No significant adverse effects were noted. Therefore, combined therapy with L1 and DFX should be considered in patients with β-thalassemia major and cardiac complications.

IKZF1 deletions predict a poor prognosis in children with B‐cell progenitor acute lymphoblastic leukemia: A multicenter analysis in Taiwan

Despite current risk‐directed therapy, approximately 15–20% of pediatric patients with acute lymphoblastic leukemia (ALL) have relapses. Recent genome‐wide analyses have identified that an alteration of IKZF1 is associated with very poor outcomes in B‐cell progenitor ALL. In this study, we determined the prognostic significance of IKZF1 deletions in patients with childhood ALL. This study analyzed 242 pediatric B‐cell progenitor ALL patients in Taiwan. We developed a simple yet sensitive multiplex quantitative PCR coupled with capillary electrophoresis to accurately determine the allele dose of IKZF1, and high resolution melting was used for mutation screening for all coding exons of IKZF1. Twenty‐six (10.7%) pediatric B‐cell progenitor ALL patients were found to harbor these deletions. Most of the deletions were broader deletions that encompassed exon 3 to exon 6, consistent with previous reports. Genomic sequencing of IKZF1 was carried out in all cases and no point mutations were identified. Patients with IKZF1 deletions had inferior event‐free survival (P < 0.001), and overall survival (P = 0.0016). The association between IKZF1 deletions and event‐free survival was independent of age, leukocyte count at presentation, and cytogenetic subtype by multivariate Cox analysis (P = 0.003, hazard ratio = 2.45). This study indicates that detection of IKZF1 deletions upon diagnosis of B‐cell progenitor ALL may help to identify patients at risk of treatment failure. IKZF1 deletions could be incorporated as a new high‐risk prognostic factor in future treatment protocols. To the best of our knowledge, this is the first study to examine the poor prognosis of IKZF1 deletions in an Asian population. (Cancer Sci 2011; 102: 1874–1881)

Poor potential of proliferation and differentiation in bone marrow mesenchymal stem cells derived from children with severe aplastic anemia

The pathogenesis of severe aplastic anemia (SAA) has not been completely understood, and insufficiency of the hematopoietic microenvironment can be an important factor. Here, we compared the basic properties of mesenchymal stem cells (MSCs), a major component of bone marrow microenvironment, from five SAA children with those of MSCs from five controls. Although MSCs from SAA children and controls were similar in morphology and immunophenotypic profile, SAA MSCs had slower expansion rate and smaller cumulative population doubling (1.83 ± 1.21 vs 3.36 ± 0.87; p = 0.046), indicating lower proliferative capacity. After osteogenic induction, SAA MSCs showed lower alkaline phosphatase activity (optical density, 1.46 ± 0.04 vs 2.27 ± 0.32; p = 0.013), less intense von Kossa staining, and lower gene expression of core binding factor α1 (0.0015 ± 0.0005 vs 0.0056 ± 0.0017; p = 0.013). Following adipogenic induction, SAA MSCs showed less intense Oil red O staining (optical density, 0.86 ± 0.22 vs 1.73 ± 0.42; p = 0.013) and lower lipoprotein lipase expression (0.0105 ± 0.0074 vs 0.0527 ± 0.0254; p = 0.013). These findings provided evidence that defects in bone marrow MSCs of SAA children do exist.

Interleukin 4, interleukin 6 and interleukin 10 polymorphisms in children with acute and chronic immune thrombocytopenic purpura

Immune thrombocytopenic purpura (ITP) is an immune‐mediated disorder. We investigated the polymorphisms of interleukin (IL)‐4 intron 3, IL‐6 (−572 G/C), and IL‐10 (−627 C/A) in 50 children with acute ITP, 30 children with chronic TIP, and 100 healthy individuals. There were significant differences in the RP1/RP2 genotype proportion (P = 0·04) and the RP2 allelic frequency (P = 0·03) of IL‐4 intron 3 and the A/C genotype proportion (P = 0·01) of IL‐10 (−627) between children with chronic ITP and controls. This finding suggests that the IL‐4 intron 3 and IL‐10 (−627) polymorphisms contribute to the susceptibility of developing childhood chronic ITP.

Cotransplantation of umbilical cord-derived mesenchymal stem cells promote hematopoietic engraftment in cord blood transplantation: a pilot study.

Background Delayed hematopoietic reconstitution after cord blood transplantation (CBT) may lead to increased risk of complications and longer hospitalization. Bone marrow–derived mesenchymal stem cells (MSCs) have been found to promote engraftment after hematopoietic stem cell transplantation. However, harvesting MSCs from bone marrow involves an invasive procedure. Then again, MSCs can be easily obtained from umbilical cords without harm to the donors. Methods Umbilical cord–derived MSCs (UCMSCs) were isolated from Wharton’s jelly and then ex vivo cultured. After showing normal karyotype and negative for infectious contamination, culture-expanded UCMSCs were intravenously infused into the recipients on the day of CBT. The control patients were those receiving CBT alone. Adverse effects and efficacy of intravenous UCMSCs were evaluated. Results A total of five patients received cotransplantation of UCMSCs at the time of CBT. No serious adverse events were observed. The time to achieve neutrophil engraftment ranged from 7 to 13 days (median, 11 days) and platelet engraftment ranged from 22 to 41 days (median, 32 days). Compared with the nine patients receiving CBT alone, patients receiving cotransplantation of UCMSCs had significantly faster hematopoietic recovery of neutrophils and platelets (P=0.02 and 0.01, respectively). Conclusions This pilot study is the first report of cotransplantation of UCMSCs in CBT. Intravenous infusion of UCMSCs appeared to be a feasible and safe modality to enhance hematopoietic engraftment in patients receiving CBT. Further studies were warranted.

An Increase in CD3+CD4+CD25+ Regulatory T Cells after Administration of Umbilical Cord-Derived Mesenchymal Stem Cells during Sepsis

Sepsis remains an important cause of death worldwide, and vigorous immune responses during sepsis could be beneficial for bacterial clearance but at the price of collateral damage to self tissues. Mesenchymal stem cells (MSCs) have been found to modulate the immune system and attenuate sepsis. In the present study, MSCs derived from bone marrow and umbilical cord were used and compared. With a cecal ligation and puncture (CLP) model, the mechanisms of MSC-mediated immunoregulation during sepsis were studied by determining the changes of circulating inflammation-associated cytokine profiles and peripheral blood mononuclear cells 18 hours after CLP-induced sepsis. In vitro, bone marrow-derived MSCs (BMMSCs) and umbilical cord-derived MSCs (UCMSCs) showed a similar morphology and surface marker expression. UCMSCs had stronger potential for osteogenesis but lower for adipogenesis than BMMSCs. Compared with rats receiving PBS only after CLP, the percentage of circulating CD3+CD4+CD25+ regulatory T (Treg) cells and the ratio of Treg cells/T cells were elevated significantly in rats receiving MSCs. Further experiment regarding Treg cell function demonstrated that the immunosuppressive capacity of Treg cells from rats with CLP-induced sepsis was decreased, but could be restored by administration of MSCs. Compared with rats receiving PBS only after CLP, serum levels of interleukin-6 and tumor necrosis factor-α were significantly lower in rats receiving MSCs after CLP. There were no differences between BMMSCs and UCMSCs. In summary, this work provides the first in vivo evidence that administering BMMSCs or UCMSCs to rats with CLP-induced sepsis could increase circulating CD3+CD4+CD25+ Treg cells and Treg cells/T cells ratio, enhance Treg cell suppressive function, and decrease serum levels of interleukin-6 and tumor necrosis factor-α, suggesting the immunomodulatory association of Treg cells and MSCs during sepsis.

Human Application of Ex Vivo Expanded Umbilical Cord-Derived Mesenchymal Stem Cells: Enhance Hematopoiesis after Cord Blood Transplantation:

Delayed hematopoietic reconstitution after cord blood (CB) transplantation (CBT) needs to be overcome. Bone marrow-derived mesenchymal stem cells (BMMSCs) have been found to enhance engraftment after hematopoietic stem cell transplantation. However, getting BMMSCs involves an invasive procedure. In this study, umbilical cord-derived mesenchymal stem cells (UCMSCs) were isolated from Whartons jelly and cryopreserved in the UCMSCs bank. Compared with BMMSCs, we found that UCMSCs had superior proliferative potential. We found that NOD/SCID mice cotransplanted with CB and UCMSCs demonstrated significant human CD45+ cell engraftment compared with those transplanted with CB alone. Then, 20 patients with high-risk leukemia were prospectively randomized to either receive cotransplantation of CB and ex vivo expanded banked UCMSCs or to receive CBT alone. No serious adverse events were observed in the patients receiving UCMSC infusion. The time to undergo neutrophil engraftment and platelet engraftment was significantly shorter in the eight patients receiving cotransplantation than that in the 12 patients receiving CBT alone (p = 0.003 and p = 0.004, respectively). Thus, application of ex vivo expanded banked UCMSCs in humans appears to be feasible and safe. UCMSCs can enhance engraftment after CBT, but further studies are warranted.

Glutathione S-Transferase M1 Gene Polymorphisms are Associated with Cardiac Iron Deposition in Patients with β-Thalassemia Major

Patients with β-thalassemia (thal) major are subject to peroxidative tissue injury by iron overload. Glutathione S-transferases work as antioxidants, and their activity is determined genetically. In this study, we used multiplex polymerase chain reaction (m-PCR) to analyze polymorphisms of two endogenous antioxidant agents, glutathione S-transferase M1 (GSTM1) and glutathione S-transferase T1 (GSTT1), and to determine their roles in 41 patients with β-thal major. Our results showed that the GSTM1 and GSTT1 null genotypes were not associated with any incidence of endocrine dysfunction (including diabetes mellitus, hypogonadism, hypothyroidism, and growth hormone deficiency), liver function, or impaired left ventricular ejection fraction (LVEF). The GSTM1 null genotype, but not the GSTT1 null genotype, was associated with a decreased signal intensity ratio on cardiac magnetic resonance imaging (MRI). Our results suggest that genetic variations of the GSTM1 enzyme are associated with cardiac iron deposition in patients with β-thal major.

The Comparison of Interleukin 6-Associated Immunosuppressive Effects of Human ESCs, Fetal-Type MSCs, and Adult-Type MSCs

Background Although human embryonic stem cells (ESCs) and mesenchymal stem cells (MSCs) from various sources display immunomodulatory effects, direct comparisons among these classes of stem cells have not been reported. Methods Peripheral blood mononuclear cell suppression assays and carboxyfluorescein diacetate succinimidyl ester assays were used to assess the immunosuppressive effects of stem cells. Gene expression was measured using DNA microarrays. Enzyme-linked immunosorbent assays were used to determine interleukin (IL)-6 levels. Results We found that fetal-type MSCs proliferated significantly faster than adult-type MSCs. Compared with ESCs grown on feeder cells, ESCs grown in feeder cell–free conditions exhibited decreased immunosuppressive effects. The suppressive effects of ESCs were significantly stronger than those of MSCs, and the suppressive effects of fetal-type MSCs were significantly stronger than those of adult-type MSCs at each tested dose level. Analysis of gene expression by microarray and MetaCore pathway mapping revealed changes in eight different immune response pathways; we observed that IL-6 gene expression was highly significantly involved in all eight pathways. Significantly higher IL-6 elevation ratios (IL-6after:IL-6before) were found in ESCs compared with fetal-type MSCs, and these were also found in fetal-type MSCs compared with adult-type MSCs. Furthermore, IL-6 levels were found to correlate with cell dosages of MSCs and the suppressive effects. Conclusions The ease of obtaining fetal-type MSCs and their rapid proliferation make these cells ideal candidates for cell-based therapies, especially for diseases associated with immune responses, given the immunosuppressive effects of these cells. IL-6 might play an important role in the immunosuppressive effects of various stem cells.