http___metro-portal.hr_maticne-stanice-su-put-do-izljecenja-teskih-bolesti-danasnjice_4388_1.xml
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Moving up the Biotechnology value chain | Corporate & Business Banking | Branch Managers in Private Banks |2 more ... this is just the basics, for more info contact me on firdoshr@yahoo.com Stem Cell Basics Stem cells have the remarkable potential to develop into many different cell types in the body. Serving as a sort of repair system for the body, they can theoretically divide without limit to replenish other cells as long as the person or animal is still alive. When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialized function, such as a muscle cell, a red blood cell, or a brain cell. Research on stem cells is advancing knowledge about how an organism develops from a single cell and how healthy cells replace damaged cells in adult organisms. This promising area of science is also leading scientists to investigate the possibility of cell-based therapies to treat disease, which is often referred to as regenerative or reparative medicine. Stem cells are one of the most fascinating areas of biology today. But like many expanding fields of scientific inquiry, research on stem cells raises scientific questions as rapidly as it generates new discoveries. What are the potential uses of human stem cells and the obstacles that must be overcome before these potential uses will be realized? There are many ways in which human stem cells can be used in basic research and in clinical research. However, there are many technical hurdles between the promise of stem cells and the realization of these uses, which will only be overcome by continued intensive stem cell research. Studies of human embryonic stem cells may yield information about the complex events that occur during human development. A primary goal of this work is to identify how undifferentiated stem cells become differentiated. Scientists know that turning genes on and off is central to this process. Some of the most serious medical conditions, such as cancer and birth defects, are due to abnormal cell division and differentiation. A better understanding of the genetic and molecular controls of these processes may yield information about how such diseases arise and suggest new strategies for therapy. A significant hurdle to this use and most uses of stem cells is that scientists do not yet fully understand the signals that turn specific genes on and off to influence the differentiation of the stem cell. Human stem cells could also be used to test new drugs. For example, new medications could be tested for safety on differentiated cells generated from human pluripotent cell lines. Other kinds of cell lines are already used in this way. Cancer cell lines, for example, are used to screen potential anti-tumor drugs. But, the availability of pluripotent stem cells would allow drug testing in a wider range of cell types. However, to screen drugs effectively, the conditions must be identical when comparing different drugs. Therefore, scientists will have to be able to precisely control the differentiation of stem cells into the specific cell type on which drugs will be tested. Current knowledge of the signals controlling differentiation fall well short of being able to mimic these conditions precisely to consistently have identical differentiated cells for each drug being tested. Perhaps the most important potential application of human stem cells is the generation of cells and tissues that could be used for cell-based therapies. Today, donated organs and tissues are often used to replace ailing or destroyed tissue, but the need for transplantable tissues and organs far outweighs the available supply. Stem cells, directed to differentiate into specific cell types, offer the possibility of a renewable source of replacement cells and tissues to treat diseases including Parkinson's and Alzheimer's diseases, spinal cord injury, stroke, burns, heart disease, diabetes, osteoarthritis, and rheumatoid arthritis. For example, it may become possible to generate healthy heart muscle cells in the laboratory and then transplant those cells into patients with chronic heart disease. Preliminary research in mice and other animals indicates that bone marrow stem cells, transplanted into a damaged heart, can generate heart muscle cells and successfully repopulate the heart tissue. Other recent studies in cell culture systems indicate that it may be possible to direct the differentiation of embryonic stem cells or adult bone marrow cells into heart muscle cells (Figure 4). In people who suffer from type I diabetes, the cells of the pancreas that normally produce insulin are destroyed by the patient's own immune system. New studies indicate that it may be possible to direct the differentiation of human embryonic stem cells in cell culture to form insulin-producing cells that eventually could be used in transplantation therapy for diabetics. To realize the promise of novel cell-based therapies for such pervasive and debilitating diseases, scientists must be able to easily and reproducibly manipulate stem cells so that they possess the necessary characteristics for successful differentiation, transplantation and engraftment. The following is a list of steps in successful cell-based treatments that scientists will have to learn to precisely control to bring such treatments to the clinic. To be useful for transplant purposes, stem cells must be reproducibly made to: - Proliferate extensively and generate sufficient quantities of tissue. - Differentiate into the desired cell type(s). - Survive in the recipient after transplant. - Integrate into the surrounding tissue after transplant. - Function appropriately for the duration of the recipient's life. - Avoid harming the recipient in any way. Also, to avoid the problem of immune rejection, scientists are experimenting with different research strategies to generate tissues that will not be rejected. To summarize, the promise of stem cell therapies is an exciting one, but significant technical hurdles remain that will only be overcome through years of intensive research. Dear firdosh sir, The stem cell information you have shared is very very helpful.i would like to ask you some doubts regarding this. In kidney failure /other kidney diseases is stem cell techniqe useful? I learn that even after transplant if you go for bone marrow transplant you don't need to take Immuno-seperative drugs which leaves you vulnurable to infections etc.how true this Techniqe as you said stem cell therapy is not a proven science as yet, and the people who are getting cured are more of clinical trials rather than therapies.do we really rely on this. Also on kidney failure disease since more than 50 years there is no innovatation in terms of drugs discovery from years only dialysis/kidney transplant has been followed. When we can expect this techniqe to become more commenly used ans reliable? pls it would be great if you could help me with the above issues. thanks sir. Thanks Firdosh for your detailed response of my query. Will surly consider for stem cell banking. Dear Mr. Satish Verma, the power of a stem cell is its capability to divide and differentiate into ANY kind of body cell. i.e a single source has a capacity to cure so many forms of human ailments and diseases. we have stem cells in the bone marrow, which is commonly used today, plus our body stores smaller qty of stem cells in the brains, nose, wisdom tooth, blood skin etc for daily maintainence activities. the richest know sources for stem cells are the 1. Bone Marrow and now the new ones are Umbilical cord Blood, Umbilical cord Lining (Whartons Jelly), Placental Blood, Amiotic Fluid and Embroynic Stem cells. if you know some body working at Christians College Vellore , they perform around 50 stem cell therapies per month for cancers on children and adults, and there is a very long waiting list. the waiting list is because PATIENTS DO NOT HAVE A SOURCE OF STEM CELLS FOR STEM CELL THERAPY. i hope u understood, the hospital cannot perform the therapy on them, because they do not have a stem cell sample to cure that disease, (our own bone marrow is not useful if we have cancer). so your question of "Is really there are no alternative of stem cell if it’s not preserved at time of birth?" there are alternative sources of stem cells, but the best and the most richest source( 50 times more than any our source) of stem cells is when the child is born, no other source can match the richness and purity of stem cells. hence people who preserve it, have done it as a BIO INSURANCE, cause if ever a situation arises for the child or some one in the family a clean, viable, and rich sample is readily available, they will not have to go hunting for a stem cell sample, and as far as paying 60,000 - 80,000 is concerned, if u have read a recent article in times this month a young boy in his 12th std was cured of cancer at apollo hospt in chennai, the parents paid Rs 48,00,000/- yes!!!!!!! Rs 48 lakhs for guess what. a STEM CELL SAMPLE. they found his match with a lady in australia, and they had to purchase it from there. so sir Rs60,000 - Rs80,000 for my own sample Vs Rs48,00,000 for buying a sample, which would u pay. now the negative part. 1.though this is a one of case, and the probability of a child ever using his/her stem cells in the lifetime is very remote, but it is still worth it, because when a life and death situation arises this sample can be very very useful. stem cell therapy is not a proven science as yet, and the people who are getting cured are more of clinical trials rather than therapies. this is a next generation technology, we may not get the advantage of using stem cells in our lifetimes, but our children will definately have that advantage. conclusion. the feed back i got from my client on why he had saved his sons stem cells. " i always wondered why my father did not invest in property, i always wondered why my father did not venture into business, if my father had bought a small flat in mumbai i would be a crorepati today by default, or if my dad has a small business today i wouldn't have to do do this stupid job. these are the question that my client didn't want his son to ask him.cause if ever a situation arises in the next 50-70 years, the son should not curse his father"why u didn't store my stem cells when i was born" regards Firdosh After going though details of stem cell technology, it looks promising and assuring for child health but really is it worth of expending Rs 60K-80K on this? Is really there are no alternative of stem cell if it’s not preserved at time of birth? Would like to hear neutral views on worth of stem cell banking in terms of money required. What are the key Pros and cons? Thanks - Create a confidential Career Profile and Resume/C.V. online - Get advice for planning their career and for marketing of experience and skills - Be with people who build and manage HR Department for companies
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Matične stanice su put do izlječenja teških bolesti današnjice Kako na najbolji način koristiti matične stanice iz pupkovine djeteta Zahvaljujući brzom napretku regenerativne medicine, šećerna bolest tip I, Parkinsonova bolest, ozljede leđne moždine ili infarkt srca u skoroj će budućnosti predstavljati manju prijetnju po zdravlje i život čovjeka. U prvom planu ove grane medicine je transplantacija matičnih stanica u bolešću ili ozljedom oštećene organe. Iako matične stanice već 30 godina koristimo u liječenju tumorskih bolesti krvi (leukemije), ili prilikom transplantacije kože kod opsežnih opekotina, u novijoj povijesti medicine ova je tema postala predmetom mnogih polemika. Što su matične stanice? Svaka stanica u našem tijelu sadrži sve gene koji su potrebni za razvoj cijelog ljudskog bića zato što su sve stanice nastale dijeljenjem prve stanice dobivene spajanjem jajne stanice i spermija. Na putu od prve stanice do cijelog organizma stanice se moraju specijalizirati zbog kompleksnosti zadaća koje obavljaju. Danas poznajemo više od 200 različitih tipova stanica. U specijaliziranim stanicama samo su određeni geni aktivni, dok je većina ostalih gena u potpunosti blokirana. Taj proces specijalizacije stanica naziva se diferencijacija. Kada jednom imamo diferencirane stanice (stanice mozga, krvne stanice, jetrene stanice, mišićne stanice...), one se rijetko ili nikada ne dijele (umnožavaju) i ne mogu se u živom organizmu više vratiti u prvotni, nespecijalizirani oblik. Nove diferencirane stanice mogu nastati jedino iz nespecijaliziranih stanica koje zovemo matične stanice. Embrionalne matične stanice Takve matične stanice mogu se gotovo neograničeno umnožavati te se u određenim uvjetima mogu specijalizirati u bilo koji tip stanica u našem tijelu, zbog čega kažemo da su one pluripotentne. Embrionalne matične stanice dobivaju se iz embrija ili zametaka (stadij blastociste) 4 - 5 dana nakon oplodnje. Dio blastociste (embrioblast) se presadi u Petrijevu posudicu te se u laboratorijskim uvjetima te stanice umnožavaju i održavaju u nespecijaliziranom obliku. Znanstvenici još uvijek ne znaju sve potrebne mehanizme koji će usmjeriti razvoj embrionalnih stanica u svih 200 tipova stanica u tijelu. Ipak, do sad je eksperimentalno dokazano da stanice gušterače nastale iz embrionalnih matičnih stanica, i transplantirane u miševe koji imaju dijabetes, proizvode inzulin i dovode do izlječenja bolesnih miševa. Kod modela srčanog infarkta, srčane mišićne stanice nastale iz embrionalnih matičnih stanica zamjenjuju oštećene mišićne stanice te uvelike pomažu u oporavku srca. Jednako tako, znanstvenici su uspjeli proizvesti i nadomjestiti neurone koji proizvode dopamin u životinjskom modelu Parkinsonove bolesti te na taj način smanjili simptome te bolesti. Iako embrionalne matične stanice najviše obećavaju, njihova je uporaba popraćena moralnim pitanjima i dilemama. Zasad se, kao izvor tih stanica koriste embriji nastali za potrebe umjetne oplodnje iako se mogu koristiti i embriji nastali transplantacijom jezgre bilo koje stanice tijela donora u neoplođenu jajnu stanicu. Taj se postupak naziva terapijsko kloniranje. Prednost ovako nastalih embrionalnih matičnih stanica je u tome što nakon transplantacije u donora ne izazivaju obrambenu (imunološku) reakciju organizma. Ti embriji nikad neće biti presađeni u maternicu u svrhu reprodukcijskog kloniranja tj. stvaranja novog genetski identičnog ljudskog bića, što je i u većini zemalja zakonski zabranjeno. Kako se prilikom prikupljanja embrionalnih matičnih stanica zametak mora žrtvovati, znanstvenici se okreću drugim tipovima matičnih stanica kao što su matične stanice odraslih ili, pak, matične stanice dobivene iz krvi pupkovine, a puno se truda i sredstava ulaže u istraživanje načina kako bi se iz diferenciranih stanica (primjerice kože) stvorile matične stanice bez uporabe jajnih stanica. Matične stanice odraslih Matične stanice odraslih, koje u tijelu čovjeka služe kao izvor specijaliziranih stanica, možemo naći u mozgu, perifernoj krvi, koštanoj srži, mišićima, koži i jetri. Primjerice, matične stanice iz odraslog mozga već su djelomično specijalizirane, tako da se mogu dalje usmjeriti jedino prema nastanku moždanih stanica (neurona te drugih stanica mozga kao što su astrociti). Takve matične stanice nazivamo multipotentnima jer iz njih može nastati samo mali broj tipova specijaliziranih stanica. Iz matičnih stanica kože može nastati samo jedan tip stanica, te se te matične stanice nazivaju unipotentnima. Problemi kod istraživanja i uporabe matičnih stanica odraslih javljaju se zato što iz njih ne mogu nastati svi tipovi stanica. Ipak odnedavno postoje naznake da se hematopoetske (krvotvorne) matične stanice iz koštane srži mogu diferencirati i u neurone, mišićne stanice, srčane stanice i stanice jetre, a moždane matične stanice u stanice krvi i mišićne stanice. Takva nedavno opisana pojava pretvorbe matičnih stanica naziva se transdiferencijacija. Matične stanice iz krvi pupkovine Velika prednost matičnih stanica dobivenih iz krvi pupkovine jednostavno je prikupljanje prilikom poroda bez opasnosti za majku i dijete te jednostavno skladištenje u tekućem dušiku na -196 ºC kroz dugi niz godina. Te stanice je odnednavno moguće uskladištiti i kod nas na Zavodu za kliničku transfuziologiju Kliničkog Zavoda za laboratorijsku dijagnostiku KBC-a Zagreb. Cijena prikupljanja uzoraka je tisuću kuna, a samog skladištenja do 18 rođendana osobe kojoj pripadaju 15 tisuća kuna. Prednost tih stanica je, kao i kod stanica dobivenih terapijskim kloniranjem, u tome što kod vraćanja tih stanica u osobu od koje su potekli ne dolazi do stvaranja obrambene reakcije. Iako su te matične stanice slične hematopoetskim matičnim stanicama, pokazano je da transdiferencijacijom iz njih mogu nastati i drugi tipovi stanica koji ne pripadaju krvi. Iako je još dosta istraživačkog rada pred nama, buduća upotreba matičnih stanica u terapiji sve većeg broja bolesti današnjice je neupitna. Hoćemo li koristiti matične stanice porijeklom iz embrija koji su ostali nakon umjetnih oplodnji, ili odrasle matične stanice, ili pak one iz pupkovine, nije samo pitanje istraživača i novih znanstvenih spoznaja, već i etičko, političko i zakonodavno pitanje, a uz to i pitanje koliko smo daleko spremni ići kako bismo iskorijenili najveće i najteže bolesti današnjice. POVIJEST MATIČNIH STANICA1981. Martin Evans sa Sveučilišta Cambridge u Velikoj Britaniji uveo je pojam embrionalne matične stanice. James Thomson sa Sveučilišta u Winsconsinu razvio je tehniku za izolaciju i održavanje ljudskih embrionalnih stanica u kulturi. Znanstvenici su uspjeli klonirati rani (4 - 6 stanica) ljudski embrio u svrhu stvaranja embrionalnih matičnih stanica. Znanstvenici sa Sveučilišta Kingston u Velikoj Britaniji otkrili su treću vrstu matičnih stanica iz krvi pupkovine. Znanstvenici u Velikoj Britaniji stvorili su umjetne stanice jetre iz matičnih stanica dobivenih iz krvi pupkovine. Mario Capecchi, Martin Evans i Oliver Smithies dobili su Nobelovu nagradu za fiziologiju i medicinu za rad na embrionalnim matičnim stanicama iz transgeničnih miševa. Steinberg GK i suradnici sa Svučilišta Stanford u SAD-u su pokazali da neuroni dobiveni iz ljudskih embrionalnih matičnih stanica dovode do oporavka štakora koji su preživjeli moždani udar.