With the advancement of science and technology, the improvement of living standards and the improvement of medical conditions, the average life expectancy of human beings has increased significantly. As the body's self-renewal capacity declines with age, the aging population is inevitably accompanied by the general occurrence of various degenerative diseases, such as cardiovascular disease, diabetes, and dementia. For example, the human body is like a machine, and birth is equivalent to leaving the machine. With the use of this machine, the parts that make up the machine will wear to varying degrees, and the longer it is used, the more severe the wear. Parts need to be repaired if the machine breaks down. Unfortunately, the parts that make up the human body are difficult to obtain. The source of organ transplantation is generally the body donated by the deceased, which is far from meeting the increasing demand. The discovery of stem cells provides a new way to solve this problem.
Stem cells are a special kind of cells. They can renew themselves and can differentiate into specific types of functional cells. According to different sources, stem cells are generally divided into embryonic stem cells and adult stem cells. Embryonic stem cells can differentiate into all types of cells in the body, and adult stem cells can differentiate into all types of cells in corresponding organs (for example, hematopoietic stem cells can differentiate into all types of cells in the hematopoietic system). Therefore, stem cells can be differentiated into specific types of functional cells (such as cardiomyocytes, islet cells, nerve cells, etc.), and then these cells can be transplanted into patients to replace damaged tissues. This is the basic principle of regenerative medicine. Compared with traditional drug therapy, cell therapy has the following advantages: drug therapy often works by interfering with certain signaling pathways, while cell therapy is to replace damaged tissues with healthy cells, and it can cure diseases fundamentally; For some diseases, especially degenerative diseases, traditional drug therapy is difficult to play a role, and can only rely on cell therapy. Stem cell research and regenerative medicine have brought new methods and hopes for the treatment of degenerative diseases, which has attracted the attention of governments of all countries and the public's attention, and has set off a wave of stem cell research and application around the world. As the global aging problem becomes more and more serious, cell therapy will surely become the mainstream of medicine in the future.
This article briefly introduces the current status of stem cell research and regenerative medicine, the problems that need to be overcome in the clinical application of stem cells, and the development trend in this field. It is divided into two parts: pluripotent stem cells and adult stem cells.
Pluripotent stem cells and regenerative medicine
Human development begins with fertilized eggs. There is a class of pluripotent cells in the early developing embryo, which will develop into various cells that make up the human body. In 1981, Martin Evans and Gail Martin established mouse embryonic stem cell lines respectively, and this achievement also allowed Martin Evans and two other scientists to win the 2007 Nobel Prize. In 1998, Thomson JA and others from the University of Wisconsin in the United States reported in Science that they had successfully established a human embryonic stem cell line for the first time. Because human embryonic stem cell lines can differentiate into any type of human body and be used for transplantation, providing a new treatment for many diseases that plague humans, the research immediately caused a huge sensation in the scientific community and created a global wave of stem cell research. In 2006, Shinya Yamanaka, a professor at Kyoto University in Japan, and others reported in Cell magazine that transfection of four transcription factors (Oct4, Sox2, Klf4, and c-Myc) to reprogram mouse fibroblasts to induce pluripotency Stem cells (induced pluripotent stem cells, iPS cells). This method solves the fatal shortcomings of the traditional method to establish patient-specific pluripotent stem cells (low efficiency and requires a large number of egg cells; the establishment of embryonic stem cell lines requires the destruction of embryos, causing moral and ethical controversy; there is currently no human nuclear transplantation pluripotent stem cell lineage successful (Report)), immediately set off a wave of iPS research in the world, and Yamanaka Yamanaka also became a popular candidate for Nobel Prize winners.
From the beginning of the successful establishment of human embryonic stem cells, scientists have tried to differentiate these cells into functional cells. By simulating the in vivo development process, scientists can now differentiate human embryonic stem cells into a variety of cells (such as neurons, cardiomyocytes, pancreatic islet cells, blood cells, etc.), and can even obtain structures similar to in vivo tissues in various animal models The above verified that these differentiated cells are functional. Tissue engineering means that these cells are planted on biological materials to further obtain tissues and even organs. At present, artificial skin and artificial bladder can be obtained.
In 2009, the US Food and Drug Administration (FDA) approved California biotechnology company Geron to carry out the world's first clinical trial based on human embryonic stem cells. The company first differentiates human embryonic stem cells into motor neurons, and then transplants these cells into about 10 paralyzed patients and observes whether these cells can restore the function of the injured spinal cord. Currently, the study is still in progress, and it is estimated that the company will announce the results of this trial in the near future. Recently, the FDA approved another company (Advanced Cell Technology) to carry out another clinical trial of human embryonic stem cells. In this study, researchers will inject retinal cells differentiated from human embryonic stem cells into the eyes of 10 patients with visual impairment. Recently, France approved the country's first clinical trial of human embryonic stem cells. George Pompidou Hospital will try to treat heart disease with cardiomyocytes differentiated from human embryonic stem cells. In the next few years, there will be more clinical trials based on human embryonic stem cells worldwide.
However, to achieve the universal application of pluripotent stem cells, a series of problems need to be solved. First, treatment based on human embryonic stem cells can cause immune rejection. Although iPS technology can effectively solve this problem, personalized treatment has the disadvantages of too high cost and long cycle. The compromise solution is to establish an iPS cell bank that covers the entire population . Secondly, the existing human embryonic stem cell differentiation methods are not efficient, and the residual undifferentiated human embryonic stem cells are transplanted into patients with the risk of long teratoma, so it is necessary to further optimize the existing differentiation methods. Third, large-scale treatment requires a large number of cells, and the existing human embryonic stem cell culture methods are time-consuming and laborious, and it is necessary to develop a batch culture system based on a bioreactor. Finally, the ideal cell therapy is to transplant tissues or even organs grown in vitro, and there are few reports in this regard. In the future, it is necessary to combine stem cell technology and tissue engineering. Go to get artificial tissues and organs.
Delight visitors to your Garden, home or patio with our vast kingdom of both exotic and local outdoor animal statues. These exclusive creations are cast in quality designer resin and individually hand painted to mimic their wild counterparts. Create your own backyard zoo of color, whimsy and danger as you move through our cute and cuddly statues to our large and menacing statues.
Easter gifts: charming beauty, rustic charm and elegant character will bring you a lot of happiness. Walk into your room, enjoy your retro/country bunny, give yourself or your kids a happy gift, it will light up your favorite space. Whether you are curling up in the living room fire, drinking tea on the porch, or walking into the bedroom, this will be an elegant addition to your decoration and make your face full of smiles.
GIFT GIVING MADE SIMPLE: Do You Want To Give A Gorgeous Gift That Stands Out From The Rest & Is The Favorite Gift Received? Something So Fabulous & Beautiful. Know You Are Giving A Gift That Will Be So Appreciated Because Of It`s Amazing Character And Ability To Fit In With Any Room & Any Decor Style. This item Comes Wonderfully Gift-Boxed For Ease Of Giving. Show Your Love To Someone Special. It's a great gift for easter day, housewarming, wedding, Christmas etc.
Easter,Shoe Storage Box,Display Shoe Case,Small Shoe Organizer,Drawer Shoe Box
HISMOK(SHENZHEN)TECHNOLOGY CO.,LTD , https://www.will-trade.com