1.Science subspecies: Stemcell-derived cells or are expected to treat congenital aplastic anemia
doi:10.1126/scitranslmed.aah5645
Recently,a study published in the international journal Science Translational Medicine,researchers from the Boston Children's Hospital stem cell research project forthe first time using the patient's own cells to develop a similar to the bonemarrow cell type, then the researchers use these new The cells were studied toidentify potential therapies for the treatment of rare blood diseases.
In thearticle, the researchers studied hematopoietic progenitor cells from twopatients with congenital aplastic anemia (DBA), a rare severe blood disorder,which showed that the patient's bone marrow could not produce enough to carryOxygen of red blood cells. First, the researchers transformed part of the skincells of the patient's body into induced pluripotent stem cells (iPSCs), thenused iPSCs to make blood pods, and loaded high-throughput drug screeningsystems in such progenitor cells. Compound library, the researchers found avariety of potential compounds in the culture dish, one of which is calledSMER28 compounds can help live mice and zebrafish began to produce largeamounts of red blood cells.
ResearchersSergei Doulatov said that when iPS cells began to manufacture blood when it isdifficult to operate it, this study we first found that the use of iPS cellscan help identify the treatment of rare blood disorders drugs. Researcherscurrently use steroids to treat DBA, but these drugs can only help about halfof the patients, some of which will eventually stop the reaction, when thesteroid drug failure, the patient must be transfused for life, so many patientsQuality of life is not ideal, the researchers believe that this compound calledSMER28 or similar compounds may be able to provide a viable alternative to thetreatment of patients.
In the case of the DBA itself, the study of bloodprogenitor cells from the patient in the petri dish does not seem to produceerythrocyte precursor cells (erythroid cells), and is the same result when thecells are transplanted into the mouse body Chemical screening seems to provideclues that erythroid cells begin to appear in small holes loaded with chemicalsubstances. Because of the strong effect, SMER28 is often pushed to additionaltests, when used in the treatment of suffering from DBA zebrafish and mice, theanimal body will produce erythroid progenitor cells, and then be able to makered blood cells, Can reverse the body's anemia performance, the researchersfound that the higher the dose of compound SMER28, there will be more red bloodcells, and there will be no side effects.
2.Cell Rep: Scientists havesucceeded in converting stem cells into precursor cells for the production ofskeletal muscle and other tissues
doi:10.1016/j.celrep.2017.01.040
Recently,a study published in the International magazine Cell Reports, researchers fromthe University of California, Los Angeles, through research found that theparticipation of body development of signal molecules (special protein) withhuman stem cells can be mixed to induce human stem cells Into the somites ofthe cells, in the development of embryos, these somatic cells can produceskeletal muscle, bone tissue and cartilage tissue; in the laboratory, thesegrowth in the culture of the body cells have Potential to grow into cells ofthe above type.
Pluripotentstem cells can be transformed into any type of cell in the body, but theresearchers want to try to guide these stem cells to produce specific tissues,such as muscle tissue, etc .; in the development of human embryos, muscle cellswith the spine and ribs Bone and cartilage, are derived from the cell clustercalled somites. Researchers have elucidated the developmental mechanisms ofsomites in animal bodies, and they have identified a special molecule that isimportant for somite development, but when the researchers try to use thesemolecules to induce human stem cells to produce somatic cells, The wholeprocess did not show a certain effect.
In the article, the researchers separated the human bodysegments with minimal development, and the expression levels of different geneswere measured before and after the complete formation of these somites. Theexpression of each gene occurred during the formation of the somites. And theresearchers later examined whether molecules that enhance or inhibit gene expressioninto human pluripotent stem cells can help promote cell transformation intosomatic cells. As a result, it has been found that the optimized molecularmixing system behaves in humans as well as in animals The performance of thebody is not the same, so the use of this new combination of molecules, theresearchers will be able to only four days in the 90% of human stem cells intosomatic cells.
3.PNAS: Scientists haveconfirmed that induction of pluripotent stem cells does not increase theprobability of occurrence of genetic mutations
doi: 10.1073/pnas.1616035114
In spiteof the potential, scientists are still very cautious and slowly using inducedpluripotent stem cells (iPSCs) in medical and drug research because these cellsare very susceptible to increasing the number of genetic mutations in the body.Recently, a study published in the International Journal Proceedings of theNational Academy of Sciences, researchers from the National Human GenomeResearch Institute, through research, said that compared to subcloned cells ,IPSCs do not seem to produce too much mutations. Subcloning is a specialtechnique in which individual cells are cultured individually and subsequentlygrown into cell lines, similar to the process of making iPSCs, but It is possibleto exclude subcloned cells that are not treated with reprogramming factors andare susceptible to mutations.
Researchers,Dr. Pu Paul Liu, said the new technology ultimately or will change the doctor'streatment of patients with disease, and this study shows that the use of iPSCssafety issues do not seem to hinder the research. Researchers in the article onthe two groups of cells were tested, one group of cells from healthyindividuals, another group of cells from patients with familial platelet disordersin the body, the use of skin samples from the same donor to study, Researchershave used iPSCs and subcloning techniques to develop cell copies that areidentical in genetic traits, and the researchers then sequenced DNA of skincells, iPSCs, and subclones, and determined that mutations in these cells wouldoccur at the same rate The
Most of the genetic mutations found by investigators iniPSCs and subcloned cells are rare genetic mutations from parental skin cells.And the results of the study show that most of the mutations in iPSCs do notoccur during reprogramming or iPSC production, which provides the researcherswith some evidence that iPSCs are very stable and that they are both basic andclinical Research can be used safely.
4.Cell: In-depthunderstanding of induced pluripotent stem cell production process
doi:10.1016/j.cell.2017.01.004
In a newstudy, researchers from the University of California, Los Angeles, Eli and theIdi-Brod Institute of Regenerative Medicine and Stem Cell Research confirmedhow specific proteins could alter the identity of skin cells or cellcharacteristics, Induced pluripotent stem cells (iPS cells). Ips cells can betransformed into any kind of cell in the body. This study may affect the formationof healthy tissues that cure the disease.
In thisnew study, the researchers added four transcription factors (Oct4, Sox2, Klf4and cMyc) to mouse skin cells to map the interaction of these transcriptionfactors with the DNA of this cell. They identified DNA sites that alter cellidentity to provide a unique understanding of how these DNA sites can producesuch effects on these cells. When they analyzed the data, they achieved two keyfindings: these transcription factors simultaneously shut down the mouse skincell identity and activation pluripotency; in these four transcription factors,there are three transcription factors need to cooperate in the positioning andregulation These DNA sites.
Further, the researchers used these data to predict whichadditional transcription factors might enhance the cell reprogramming processfollowed by the addition of a fifth transcription factor into these mouse skincells. This new transcription factor combination is more efficient ininhibiting the identity of these tissue-specific cells, which will acceleratethe transition to pluripotency, increasing the efficiency of this cellreprogramming process.
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