Using Targeted Sequencing of Paralogous Sequences for Noninvasive Detection of Selected Fetal Aneuploidies.

BACKGROUND: Current methods for noninvasive prenatal testing (NIPT) ascertain fetal aneuploidies using either direct counting measures of DNA fragments from specific genomic regions or relative measures of single nucleotide polymorphism frequencies. Alternatively, the ratios of paralogous sequence pairs were predicted to reflect fetal aneuploidy. We developed a NIPT assay that uses paralog sequences to enable noninvasive detection of fetal trisomy 21 (T21) and trisomy 18 (T18) using cell-free DNA (cfDNA) from maternal plasma. METHODS: A total of 1060 primer pairs were designed to determine fetal aneuploidy status, fetal sex, and fetal fraction. Each library was prepared from cfDNA by coamplifying all 1060 target pairs together in a single reaction well. Products were measured using massively parallel sequencing and deviations from expected paralog ratios were determined based on the read depth from each paralog. RESULTS: We evaluated this assay in a blinded set of 480 cfDNA samples with fetal aneuploidy status determined by the MaterniT21® PLUS assay. Samples were sequenced (mean = 2.3 million reads) with 432 samples returning a result. Using the MaterniT21 PLUS assay for paired plasma aliquots from the same individuals as a reference, all 385 euploid samples, all 31 T21 samples, and 14 of 16 T18 samples were detected with no false positive results observed. CONCLUSIONS: This study introduces a novel NIPT aneuploidy detection approach using targeted sequencing of paralog motifs and establishes proof-of-concept for a potentially low-cost, highly scalable method for the identification of selected fetal aneuploidies with performance and nonreportable rate similar to other published methods.

Good Engraftment but Quality and Donor Concerns for Cryopreserved Hemopoietic Progenitor Cell Products Collected During the COVID-19 Pandemic.

Changes to donor availability, collection center capacity, and travel restrictions during the early phase of the COVID-19 pandemic led to routine cryopreservation of most unrelated donor products for hematopoietic transplantation prior to the recipient commencing the conditioning regimen. We investigated the effect of this change on unrelated donor product quality and clinical outcomes. Product information was requested from transplantation centers in Australia and New Zealand and clinical outcome data from the Australasian Bone Marrow Transplant Recipient Registry (ABMTRR). In total, 191 products were collected between April 1, 2021, and September 30, 2021, and most (74%) were from international collection centers. Median post-thaw CD34 recovery was 78% (range 25% to 176%) and median post-thaw CD34 viability was 87% (range 34% to 112%). Median time to neutrophil recovery was 17 days (interquartile range 10 to 24 days), and graft failure occurred in 6 patients (4%). These clinical outcomes were similar to those of "fresh" unrelated donor transplants reported to the ABMTRR in 2019. However, recipient transplantation centers reported problems with 29% of products in the form of damage during transit, low cell dose, inadequate labeling, missing representative samples, or missing documentation. These problems were critical in 7 cases (4%). At last follow-up, 22 products (12%) had not been infused. Routine cryopreservation of unrelated donor hemopoietic progenitor cell products has enabled safe continuation of allogeneic transplant services during the COVID-19 pandemic. However, practices for product tracing, documentation, and transportation can be optimized, and measures to reduce the incidence of unused unrelated donor product are required.

The role of BMP-7 in chondrogenic and osteogenic differentiation of human bone marrow multipotent mesenchymal stromal cells in vitro.

This study addresses the role of bone morphogenetic protein-7 (BMP-7) in chondrogenic and osteogenic differentiation of human bone marrow multipotent mesenchymal stromal cells (BM MSCs) in vitro. BM MSCs were expanded and differentiated in the presence or absence of BMP-7 in monolayer and three-dimensional cultures. After 3 days of stimulation, BMP-7 significantly inhibited MSC growth in expansion cultures. When supplemented in commonly used induction media for 7-21 days, BMP-7 facilitated both chondrogenic and osteogenic differentiation of MSCs. This was evident by specific gene and protein expression analyses using real-time PCR, Western blot, histological, and immunohistochemical staining. BMP-7 supplementation appeared to enhance upregulation of lineage-specific markers, such as type II and type IX collagens (COL2A1, COL9A1) in chondrogenic and secreted phosphoprotein 1 (SPP1), osteocalcin (BGLAP), and osterix (SP7) in osteogenic differentiation. BMP-7 in the presence of TGF-beta3 induced superior chondrocytic proteoglycan accumulation, type II collagen, and SOX9 protein expression in alginate and pellet cultures compared to either factor alone. BMP-7 increased alkaline phosphatase activity and dose-dependently accelerated calcium mineralization of osteogenic differentiated MSCs. The potential of BMP-7 to promote adipogenesis of MSCs was restricted under osteogenic conditions, despite upregulation of adipocyte gene expression. These data suggest that BMP-7 is not a singular lineage determinant, rather it promotes both chondrogenic and osteogenic differentiation of MSCs by co-ordinating with initial lineage-specific signals to accelerate cell fate determination. BMP-7 may be a useful enhancer of in vitro differentiation of BM MSCs for cell-based tissue repair.

Direct Comparison of Four Hematopoietic Differentiation Methods from Human Induced Pluripotent Stem Cells.

Induced pluripotent stem cells (iPSCs) are an invaluable resource for the study of human disease. However, there are no standardized methods for differentiation into hematopoietic cells, and there is a lack of robust, direct comparisons of different methodologies. In the current study we improved a feeder-free, serum-free method for generation of hematopoietic cells from iPSCs, and directly compared this with three other commonly used strategies with respect to efficiency, repeatability, hands-on time, and cost. We also investigated their capability and sensitivity to model genetic hematopoietic disorders in cells derived from Down syndrome and ß-thalassemia patients. Of these methods, a multistep monolayer-based method incorporating aryl hydrocarbon receptor hyperactivation ("2D-multistep") was the most efficient, generating significantly higher numbers of CD34+ progenitor cells and functional hematopoietic progenitors, while being the most time- and cost-effective and most accurately recapitulating phenotypes of Down syndrome and ß-thalassemia.

Safety and efficacy of consecutive cycles of granulocyte-colony stimulating factor, and an intracoronary CD133+ cell infusion in patients with chronic refractory ischemic heart disease: the G-CSF in angina patients with IHD to stimulate neovascularization (GAIN I) trial.

BACKGROUND: Preclinical studies suggest granulocyte-colony stimulating factor (G-CSF) holds promise for treating ischemic heart disease; however; its clinical safety and efficacy in this setting remain unclear. We elected to evaluate the safety and efficacy of G-CSF administration in patients with refractory "no-option" ischemic heart disease. METHODS: Twenty patients (18 males, 2 females, mean age 62.4 years) were enrolled and underwent baseline cardiac ischemia assessment (CA) (angina questionnaire, exercise stress test [EST], technetium Tc 99m sestamibi and dobutamine-stress echocardiographic imaging). Patients then received open-label G-CSF commencing at 10 microg/kg SC for 5 days, with an EST on days 4 and 6 (to facilitate myocardial cytokine generation and stem cell trafficking). After 3 months, CA and the same regimen of G-CSF+ESTs were repeated but, in addition, leukapheresis and a randomized double-blinded intracoronary infusion of CD133+ or unselected cells were performed. Final CA occurred 3 months thereafter. RESULTS: There were no deaths, but only 16 patients were permitted to complete the study. Eight events fulfilled prespecified "adverse event" criteria, including 4 troponin I-positive events and 2 episodes of thrombocytopenia. Also, frequent minor troponin I-positive events (troponin I<0.9 microg/L) were observed, which did not meet adverse event criteria. The administration of consecutive cycles of G-CSF resulted in stepwise improvements in anginal frequency, EST performance, and Duke treadmill scores (all P<.005). However, from baseline to final follow-up, technetium Tc 99m sestamibi and dobutamine-stress echocardiographic results were unchanged. CONCLUSIONS: Granulocyte-colony stimulating factor administration was associated with improvement in a range of subjective outcomes. However, adverse events were common, and objective measures of cardiac perfusion/ischemia were unchanged.

Evidence for transdifferentiation of human bone marrow-derived stem cells: recent progress and controversies.

Adult bone marrow-derived stem cells have traditionally been known as tissue-specific stem cells capable of producing blood cells. This concept is being challenged by a series of recent discoveries. It has been demonstrated that there are heterogeneous stem cell populations in adult bone marrow compartment. Under appropriate experimental conditions, a certain type of bone marrow stem cells appears to differentiate (or transdifferentiate) into a variety of non-haemopoietic cells of ectodermal, mesodermal and endodermal origins (such as myocytes, neural cells and hepatocytes). The plasticity, that is, the ability to regenerate cells belonging to different organs and tissues of adult (postnatal) stem cells, has raised the therapeutic possibility of using these stem cells for tissue repair and regeneration. Presently, definitive evidence for plasticity or transdifferentiation of bone marrow stem cells is lacking. Despite controversies concerning the plasticity of bone marrow-derived stem cells, early clinical trials are being conducted in patients suffering from myocardial infarct, arthritic and neurological diseases using autologous bone marrow stem cells. This review summarises recent progresses and controversies in transdifferentiation of adult bone marrow-derived stem cells to non-haemopoietic tissues.

Cell therapy for disc degeneration--potentials and pitfalls.

Disc degeneration is considered a major source of pain in patients with chronic low back pain. Novel strategies to cure or decrease the symptoms and increase the patient's quality of life and function are under development. Until recently conservative treatment and fusion surgery were the main therapeutic options. Disc prostheses are undergoing clinical evaluation. The potential for cell transplantation to the intervertebral disc with mature autologous disc cells, chondrocytes, or stem cells is in early stages of investigation. Cell transplantation potentially can increase proteoglycan production and induce disc regeneration or slow down the degeneration process. In animal models, transplantation of autologous disc cells and chondrocytes (derived from costal cartilage) has been demonstrated to be feasible and may slow disc degeneration.

Transplantation of neuronal-primed human bone marrow mesenchymal stem cells in hemiparkinsonian rodents.

Bone marrow-derived human mesenchymal stem cells (hMSCs) have shown promise in in vitro neuronal differentiation and in cellular therapy for neurodegenerative disorders, including Parkinson' disease. However, the effects of intracerebral transplantation are not well defined, and studies do not agreed on the optimal neuronal differentiation method. Here, we investigated three growth factor-based neuronal differentiation procedures (using FGF-2/EGF/PDGF/SHH/FGF-8/GDNF), and found all to be capable of eliciting an immature neural phenotype, in terms of cell morphology and gene/protein expression. The neuronal-priming (FGF-2/EGF) method induced neurosphere-like formation and the highest NES and NR4A2 expression by hMSCs. Transplantation of undifferentiated and neuronal-primed hMSCs into the striatum and substantia nigra of 6-OHDA-lesioned hemiparkinsonian rats revealed transient graft survival of 7 days, despite the reported immunosuppressive properties of MSCs and cyclosporine-immunosuppression of rats. Neither differentiation of hMSCs nor induction of host neurogenesis was observed at injection sites, and hMSCs continued producing mesodermal fibronectin. Strategies for improving engraftment and differentiation post-transplantation, such as prior in vitro neuronal-priming, nigral and striatal grafting, and co-transplantation of olfactory ensheathing cells that promote neural regeneration, were unable to provide advantages. Innate inflammatory responses (Iba-1-positive microglia/macrophage and GFAP-positive astrocyte activation and accumulation) were detected around grafts within 7 days. Our findings indicate that growth factor-based methods allow hMSC differentiation toward immature neuronal-like cells, and contrary to previous reports, only transient survival and engraftment of hMSCs occurs following transplantation in immunosuppressed hemiparkinsonian rats. In addition, suppression of host innate inflammatory responses may be a key factor for improving hMSC survival and engraftment.

BMP-13 emerges as a potential inhibitor of bone formation.

Bone morphogenetic protein-13 (BMP-13) plays an important role in skeletal development. In the light of a recent report that mutations in the BMP-13 gene are associated with spine vertebral fusion in Klippel-Feil syndrome, we hypothesized that BMP-13 signaling is crucial for regulating embryonic endochondral ossification. In this study, we found that BMP-13 inhibited the osteogenic differentiation of human bone marrow multipotent mesenchymal stromal cells (BM MSCs) in vitro. The endogenous BMP-13 gene expression in MSCs was examined under expansion conditions. The MSCs were then induced to differentiate into osteoblasts in osteo-inductive medium containing exogenous BMP-13. Gene expression was analysed by real-time PCR. Alkaline phosphatase (ALP) expression and activity, proteoglycan (PG) synthesis and matrix mineralization were assessed by cytological staining or ALP assay. Results showed that endogenous BMP-13 mRNA expression was higher than BMP-2 or -7 during MSC growth. BMP-13 supplementation strongly inhibited matrix mineralization and ALP activity of osteogenic differentiated MSCs, yet increased PG synthesis under the same conditions. In conclusion, BMP-13 inhibited osteogenic differentiation of MSCs, implying that functional mutations or deficiency of BMP-13 may allow excess bone formation. Our finding provides an insight into the molecular mechanisms and the therapeutic potential of BMP-13 in restricting pathological bone formation.

The fate of transplanted xenogeneic bone marrow-derived stem cells in rat intervertebral discs.

Intervertebral disc degeneration is a major cause and a risk factor for chronic low back pain. The potential of using stem cells to treat disc degeneration has been raised. The aims of our study were to assess whether xenogeneic bone-marrow derived stem cells could survive in a rat disc degeneration model and to determine which cell types, if any, survived and differentiated into disc-like cells. Human bone-marrow derived CD34(+) (hematopoietic progenitor cells) and CD34(-) (nonhematopoietic progenitor cells, including mesenchymal stem cells) cells were isolated, fluorescent-labeled, and injected into rat coccygeal discs. The rats were sacrificed at day 1, 10, 21, and 42. Treated discs were examined by histological and immunostaining techniques and compared to control discs. The survival of transplanted cells was further confirmed with a human nuclear specific marker. Fluorescent labeled CD34(-) cells were detected until day 42 in the nucleus pulposus of the injected discs. After 3 weeks these cells had differentiated into cells expressing chondrocytic phenotype (Collagen II and Sox-9). In contrast, the fluorescent labeled CD34(+) cells could not be detected after day 21. No fluorescence-positive cells were detected in the noninjected control discs. Further, no inflammatory cells infiltrated the nucleus pulposus, even though these animals had not received immunosuppressive treatment. Our data provide evidence that transplanted human BM CD34(-) cells survived and differentiated within the relative immune privileged nucleus pulposus of intervertebral disc degeneration.

BMP-2 enhances TGF-beta3-mediated chondrogenic differentiation of human bone marrow multipotent mesenchymal stromal cells in alginate bead culture.

This study addresses synergistic effects of bone morphogenetic protein-2 (BMP-2) and transforming growth factor-beta3 (TGF-beta3) in the induction of chondrocytic differentiation of bone marrow multipotent mesenchymal stromal cells (BM MSCs) in vitro for potential use in intervertebral disc (IVD) repair. Human BM MSCs encapsulated in alginate beads were induced to differentiate in serum-free medium containing BMP-2 and TGF-beta3. The expression of chondrocytic genes and proteins was analyzed by real-time PCR, western blot, histological, and immunohistochemical assays. This differentiation system showed a potent induction of chondrocytic phenotypes. The expression of chondrocytic markers, such as aggrecan (ACAN) and type II collagen (COL2A1), was upregulated at higher levels than using TGF-beta3 alone. Blocking BMP-2 by noggin completely suppressed BMP-2-enhanced gene and protein expression, confirming a crucial input of BMP-2 signaling in this differentiation process. Inhibition of extracellular signal-regulated kinases 1 and 2 signaling resulted in an increase in ACAN and COL2A1 gene expression, suggesting a negative regulatory role of this pathway. In conclusion, BMP-2 enhances TGF-beta3-mediated chondrogenesis of MSCs. The combination of BMP-2 and TGF-beta3 in alginate culture is superior to the standard differentiation method using TGF-beta alone. This potent induction system may provide an alternative cell source for IVD and cartilage regeneration in clinical practice.

Differentiation of rodent bone marrow mesenchymal stem cells into intervertebral disc-like cells following coculture with rat disc tissue.

This study aimed to evaluate whether rat mesenchymal stem cells (rMSCs) could be differentiated in vitro into disc-like cells by coculturing with intervertebral disc tissue. rMSCs were cultured with rodent intervertebral disc for up to 30 days in transwell plates. The differentiation of rMSCs was evaluated by immunostaining, Western blot, real-time RT-PCR, Northern blot, and electron microscopy. The potentials of multilineage differentiation and proteoglycan and collagen synthesis were also investigated. rMSCs underwent morphological changes to form three-dimensional micromasses and expressed collagen-2, aggrecan, and sox-9 at RNA and protein levels after 14 days of coculture. These changes were not detected in the samples of rMSCs cultured alone. Cocultured rMSCs also showed other characteristic features of disc-like cells, including the extracellular matrix formation, and proteoglycan and collagen synthesis. In addition, cellular contact between cocultured rMSCs and disc tissue was observed by electron microscopy. Committed rMSCs still retained their differentiation ability into mesoderm lineages of adipocytes or osteocytes when the local environment was altered. This study supports that MSCs are a promising source for cell therapy and tissue engineering in disc regeneration, and highlights that rMSCs can be induced into nucleus pulposus-like cells in vitro under the direct influence of intact disc tissue.

Long-term serial passage and neuronal differentiation capability of human bone marrow mesenchymal stem cells.

The development of methods to induce differentiation of human mesenchymal stem cells (hMSCs) has opened the possibility of using these cells in regenerative or reparative therapies. However, the low frequency of hMSCs in tissue means it is often necessary to expand these cells extensively in vitro. In this study, we evaluated the effects of long-term serial passage on the characteristics of bone marrow-derived hMSC populations. In addition, we examined the effect on subsequent hMSC neural differentiation ability, which has not been reported earlier. The hMSC population examined was found to maintain a stable phenotype during the first 6-8 passages of culture as assessed by proliferative ability, morphological appearance, and surface antigen, gene and protein expression, and also expressed pluripotency and neural lineage markers constitutively in the undifferentiated state. Long-term subcultivation neither resulted in spontaneous neural differentiation nor compromised the ability of hMSCs to develop toward an early neuronal fate. In addition, the transformation elicited in hMSC cultures in response to cytokine-based neuronal differentiation was examined by live cell microscopy. We demonstrated, for the first time, that the observed changes result from active and dynamic processes involving outgrowth and motility of cellular extensions, processes entirely distinct from the rapid epiphenomena of cytotoxicity and cytoskeleton disruption generated by chemical induction methods. Cytokine-induced differentiation of hMSCs was also associated with upregulation of early neural gene and protein expression. These findings support the neuronal differentiation capability of hMSCs, although further investigation is required to confirm the ability to attain a mature neuronal phenotype.

Cytokine-induced stable neuronal differentiation of human bone marrow mesenchymal stem cells in a serum/feeder cell-free condition.

The characteristics and multilineage differentiation potential of bone marrow mesenchymal stem cells (BM MSC) remain controversial. This study aimed to characterize human BM MSC isolated by plastic adherent or antibody selection and their neuronal differentiation potential using growth factors or chemical inducing agents. MSC were found to express low levels of neuronal markers: neurofilament-M, beta tubulin III, and neuron specific enolase. Under a serum- and feeder cell-free condition, basic fibroblast growth factor, epidermal growth factor, and platelet-derived growth factor induced neuronal morphology in MSC. In addition to the above markers, these cells expressed neurotransmitters or associated proteins: gamma-aminobutyric acid, tyrosine hydroxylase and serotonin. These changes were maintained for up to 3 months in all bone marrow specimens (N = 6). In contrast, butylated hydroxyanisole and dimethylsulfoxide were unable to induce sustained neuronal differentiation. Our results show that MSC isolated by two different procedures produced identical lineage differentiation with defined growth factors in a serum- and feeder cell-free condition.

Study on induction of ginsenosides on HL-60 cell apoptosis / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe whether the Ginsenosides (GS) could induce HL-60 cell line apoptosis from promyelocytic leukemia.</p><p><b>METHODS</b>HL-60 cells were treated with GS of various concentration to observe the effect of GS on cell morphological change, the DNA content change by flow cytometry, DNA ladder by electrophoresis, and apoptosis rate by Annexin V-FITC test of the cells.</p><p><b>RESULTS</b>GS could inhibit the growth of HL-60 cells and induce cell apoptosis in a certain scope of dose and reacting time.</p><p><b>CONCLUSION</b>GS could specifically induce apoptosis in HL-60 cells, which provides an experimental basis for treatment of leukemia with GS as an supplemntary agent of chemotherapy.</p>