Latest Research Advances in Hematopoietic Stem Cells (No. 7)

December 28, 2020 // --- Hematopoietic Stem Cell (HSC) is a group of primitive hematopoietic cells present in hematopoietic tissue, which are not tissue-fixed cells and can be present in hematopoietic tissue and blood.
stem cells can appear in the egg yolk sac at 2 weeks in a human embryo, and after 5 months of pregnancy, the bone marrow begins to make blood, and the bone marrow becomes the main source of stem cells after birth.
is a small proportion of hemastation tissue.
modern medicine, hematopoietic stem cells play an important role in bone marrow transplantation and disease treatment.
1988, Professor Guckman of France pioneered the successful use of cord blood stem cell transplantation, which treated a child with anemia and marked the beginning of the era of cord hematopoietic stem cell transplantation.
about 60,000 bone marrow transplants are performed globally each year, of which nearly 35,000 and 25,000 are performed using both autobiographic and allogeneic hematopoietic stem cells.
of hematopoietic stem cells mainly include bone marrow, exostemia and umbilical cord blood.
, "bone marrow transplantation" has gradually been replaced by "outer hematopoietic stem cell transplantation."
, the donated bone marrow is no longer a bone marrow extract, but a "blood donation."
cord blood is the blood left in the umbilical cord and placenta after the fetus gives birth, rich in hematopoietic stem cells, can be used to treat acute, chronic leukemia and certain malignant tumors and other major diseases.
based on this, the editor-in-chief combed through the progress made in hematopoietic stem cell research in recent years in order to reach out to readers.
1.ScienceDaily: Great progress! In a new study, researchers at Yale University in the United States discovered a key biological link in the transformation of endosperm cells into hematopoietic stem cells and progenitor cells (HSPC).
study was published in the December 4, 2020 issue of the journal Science under the title "The N-glycome regulators the endothelial-to-hematopoietic transition."
stem cell differentiation, pictured from Wikipedia.
reprogramming cells as HSPC has always been the highest goal of self-stem cell transplantation and is a life-saving treatment for blood cancer diseases.
, little is known about the mechanisms that regulate this shift at the cellular and molecular levels.
in the new study, the authors found a key link between a complex sugar called polysaccharine and endothelial-to-hematopoietic, EHT.
EHT is a process that differentiates from blood-borne endoskine cells to HSPC.
2.Cell Rep: Scientists have developed a new method or energy source to produce hematopoietic stem cells doi:10.1016/j.celrep.2020.108474 In a study published in the international journal Cell Reports, scientists from institutions such as the Spanish Genome Control Center and Columbia University identified a special protein that is critical to the expansion of scarce, life-saving hematopoietic stem cells (HSC).
Research may help scientists develop new ways to reproduce large numbers of these stem cells in and out of the body, which are currently one of the biggest limitations scientists use in a variety of medical procedures, from treatments for blood cancer to genetic blood diseases that require bone marrow transplants.
one way to get more HSCs is to expand the number of hematopoietic stem cells present in bone marrow, circulating blood, or cord blood;
researchers say that in this study, we identified a specific protein that can reprogram other blood stem cells using an algorithm called VIPER, and of the eight potential candidates identified by the algorithm, only one gene called BAZ2B significantly expanded the number of hematopoietic stem cells in umbilical cord blood.
BAZ2B gene can reprogram blood stem cells to an HSC-like state by re-excreting chromatin from blood stem cells, thus opening up unique areas of the genome that were previously inadienable, and the resulting cells can be successfully transplanted into the bone marrow of mice with low immunity to renew tissue growth.
3.Cell Stem Cell Explained! The mystery of the switch of artificial blood stem cells from latent to active: 10.1016/j.stem.2020.11.001 In a new study, researchers from research institutions such as Princess Margaret Cancer Center in Canada, the University of Toronto and the Ontario Cancer Institute have revealed how hematopoietic stem cells (HSCs) can produce new blood cells in our lifetimes by looking at vast, unknown areas of our genetic material.
these regions hold important clues to subtle biological changes in these cells.
results were published online November 25, 2020 in the journal Cell Stem Cell under the title "The Transition from Questcent to Activated States in Human Hematopoietic Stems Cell Is Governed by Dynamics 3D Genome Reorganization."
and John Dick of Princess Margaret Cancer Centre.
from Cell Stem Cell, 2020, doi:10.1016/j.stem.2020.11.001.
researchers looked at two different types of human hematopoietic stem cells, which take several steps to develop immature cells into different types of blood cells, such as white blood cells, red blood cells, and plate plate plates.
they studied long-acting hematopoietic stem cells (long-term HSC) and short-acting hematopoietic stem cells (short-term HSC) found in human bone marrow.
They wanted to map out the cellular mechanisms involved in the "sleep" state of long-acting hematopoietic stem cells with continuous self-renewal capabilities, compared with the ability of short-acting hematopoietic stem cells to be activated more easily and at any time, and thus to quickly transform into a variety of blood cells.
These researchers found differences in the three-dimensional chromatin structure between the two types of hematopoietic stem cells, which is significant because chromatin arrangement or folding and ringing affect the expression and regulation of genes and other parts of the genome.
4.Science: The intrinsic mechanism of hematopoietic stem cell transplant immune rejection doi:10.1126/scitranslmed.abb7028 In the treatment of leukemia, hematopoietic stem cell transplantation after chemotherapy and radiation therapy usually causes severe adverse inflammatory reactions, especially in the skin or intestines, because these so-called "barrier" organs are more susceptible.
so far, the cause is unclear.
team, led by Georg Stary and Johanna Strobl of MedUni's Vienna Dermatology Department, has now identified an immune mechanism.
results are now published in the journal Science Translational Medicine.
leukemia is a malignant disease used to describe the cancer of the hematocyte system, in which white blood cell prelogues proliferate uncontrolled.
treatments for leukemia, chemotherapy and radiotherapy are used to destroy abnormal cells and then replace them with normal stem cell transplants.
in leukemia, transplants of healthy bone marrow stem cells or hematopoietic stem cells are often the only hope for recovery.
. Two Nature papers reveal that mutations that promote the growth of hematopoietic stem cells increase the risk of leukemia and cardiovascular disease doi:10.1038/s41586-020-2786-7; doi:10.1038/s41586-020-2819-2 As people get older, hematopoietic stem cells (HSC) ---formed stem cells that produce blood cells and immune cells--- certain genetic mutations eventually lead to cancer or make people susceptible to cardiovascular disease.
Now, in two new studies, two teams from the Broad Institute, Massachusetts General Hospital, Boston Children's Hospital and the Dana-Farber Cancer Institute have each identified a set of genetic mutations that increase the risk that hematopoietic stem cells will accumulate these mutations through their lifetimes.
these mutations can lead to two age-related blood diseases--- myeloproliferative neoplasm (MPN) and undetermined potential cloned blood (clonal hematopoiesis of indeterminate potential, CHIP) --- one.
people with MPN have too many mature red blood cells, white blood cells and plateplates, which makes them prone to leukemia.
CHIP causes too many hematopoietic stem cells, which affect nearly 10 percent of people over the age of 70 and increase a person's risk of cancer and heart disease.
images from Nature, 2020, doi:10.1038/s41586-020-2819-2.
results suggest that some genetic mutations promote self-renewal of hematopoietic stem cells, which can lead to the expansion of hematopoietic stem cell pools.
increases the risk of blood cells accumulating harmful mutations over time that can lead to MPN or CHIP.
results were recently published in two Nature papers entitled "Inherited myeloproliferative neoplasm risk affects haematopoietic stem cells" and "Inherited causes of clonal haematopoiesis in 97,691 whole genomes".
6.Stem Cell Rep: Heavy! Scientists find super hematopoietic stem cells in human embryos! Its proliferation capacity is 200-500 times that of hematopoietic stem cells in cord blood! doi:10.1016/j.stemcr.2020.08.008 In a recent study published in the international journal Stem Cell Reports, scientists from the University of Edinburgh and others found in human embryos. A super-potential hematopoietic stem cell that is derived from the body's blood and immune system, commonly known as hematopoietic stem cells, has important applications in the development of new treatments for blood cancer and other cancers of the immune system.
In the study, researchers found special hematopoietic stem cells from early human embryos that, when they first formed, were more likely to expand than stem cells in cord blood; The proliferation produced more hematopoietic stem cell levels and abilities, and it was found that when transplanted into the mouse body, the level of hematopoietic stem cells in embryos was 200-500 times higher than that of hematopoietic stem cells in umbilical cord blood.
7.Science: Hematopoietic stem cell transplantation will result in a decrease in the number of intestinal cup cells doi:10.1126/scitranslmed.aaw0720 clinical practice has shown that allogeneic stem cell transplantation can lead to the loss of protective cup cells in the inner walls of the colon, which can lead to fatal consequences.
a recent study, supplementing these cells in advance can improve symptoms.
loss of colon cells after stem cell transplantation can lead to bacterial infections and affect the patient's prognostics.
a new study published in the journal Science Translational Medicine by researchers at Hokkaido University, pre-transplant injection of cup cell growth factors can improve prognostics.
study in mice, the researchers found that hematopoietic stem cell transplantation of the same species could lead to a significant reduction in the endosthel cells in the inner walls of the colon called cup cells.
found that a reduction in mature cup cells after transplantation led to the destruction of the mucus layer they formed, eventually leading bacteria to invade intestinal tissue.
, the number of cup cells in the colon increased significantly after scientists injected mice with the cup cell growth factor interlebin 25 (IL-25) six days before the transplant.
mice injected with IL-25, there was a significant decrease in the number of bacteria that could invade the mucous membranes of the intestine after transplantation of allogeneic stem cells.
Further research shows that another type of colon cell secretes an antimicrobial molecule called Lypd8.
they also found that Ly