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Thread: Dr. Young - Has Dr. Black shown long term survival and engraftment of adult bone marrow stromal cell

  1. #1

    Dr. Young - Has Dr. Black shown long term survival and engraftment of adult bone marrow stromal cell

    I must be missing something. Does this or does this not indicate that MSCs differentiate into neurons, survive and function normally invivo? Please advise.

    The Journal of Neuroscience, May 12, 2004, 24(19): 4585-4595

    Adult Bone Marrow Stromal Cells in the Embryonic Brain: Engraftment, Migration, Differentiation, and Long-Term Survival

    Guillermo Muñoz-Elias, Akiva J. Marcus, Thomas M. Coyne, Dale Woodbury, and Ira B. Black

    Department of Neuroscience and Cell Biology and the Stem Cell Research Center, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway, New Jersey 08854-5635


    We recently differentiated adult rat and human bone marrow stromal cells (MSCs) into presumptive neurons in cell culture. To determine whether the MSCs assume neuronal functions in vivo, we now characterize for the first time engraftment, migration, phenotypic expression, and long-term survival after infusion into embryonic day 15.5 (E15.5) rat ventricles in utero. By E17.5, donor cells formed discrete spheres in periventricular germinal zones, suggesting preferential sites of engraftment. The cells expressed progenitor vimentin and nestin but not mature neuronal markers. By E19.5, a subset assumed elongated migratory morphologies apposed to radial nestin-positive fibers running through the cortical white matter and plate, suggesting migration along radial glial processes. Cells remaining in germinal zones extended long, vimentin-positive fibers into the parenchyma, suggesting that the MSCs generated both migratory neurons and guiding radial glia. Consistent with this suggestion, >50% of cultured mouse MSCs expressed the neuroprecursor/radial glial protein RC2. From E19.5 to postnatal day 3, MSCs populated distant areas, including the neocortices, hippocampi, rostral migratory stream, and olfactory bulbs. Whereas donor cells confined to the subventricular zone continued to express nestin, cells in the neocortex and midbrain expressed mature neuronal markers. The donor cells survived for at least 2 months postnatally, the longest time examined. Confocal analysis revealed survival of thousands of cells per cubic millimeter in the frontal cortex and olfactory bulb at 1 month. In the cortex and bulb, 98.6 and 77.3% were NeuN (neuronal-specific nuclear protein) positive, respectively. Our observations suggest that transplanted adult MSCs differentiate in a regionally and temporally specific manner.


    Key words: stem cells; embryonic brain; neurons; development; neurogenesis; differentiation

    What we do in life echoes in eternity. Maximus - Gladiator

  2. #2
    larwatson, this study suggests that the embryonic brain contains the signals that tell bone marrow stem cells to produce neurons. While there was initially a lot of excitement about the possibility of bone marrow stem cells converting to neurons in culture and the suggestion that this is possible when the cells have been transplanted to the spinal cord, this has not turned out to be the case when the cells are transplanted into adult brain or spinal cord, at least not yet.

    I have commented extensively on this subject in other topics:
    Stem Cells From Whole Adult Bone Marrow Differentiated Into Central Nervous System Cells
    Dr. Ira Black
    Why So Long?
    Rationale against the use of embryonic stem cells
    Why the SCI Community should continue to press on the ESC issue.

    Wise.

    [This message was edited by Wise Young on 10-05-04 at 07:06 AM.]

  3. #3
    Senior Member DA's Avatar
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    dr young you are always ragging on asc. finish the research before you dismiss them. all avenues must explored, right?

  4. #4
    DA,

    I rag on everything. That is what scientists are supposed to do.

    The paper by Ira Black (Munoz-Elias, et al. 2004) is important. What they showed was that bone marrow stromal cells survive, migrate, and express vimentin and nestin when transplanted into fetal brains. The cells that end up in the neocortex apparently express mature neuronal markers (NeuN). It has been four years since Ira first reported that they were able to grow neuron-like cells from bone marrow cells (Munoz-Elias, et al., 2003). They have transplanted to the spinal cord and, like many other groups, have not seen the kind of results that have been reported with embryonic stem cells reported by McDonald (2002, 2004), i.e. some 70% of the cells become astrocytes, 20% produce oligodendroglial cells, and 10% produce neurons. Many groups have been transplanting bone marrow stem cells into the spinal cord injury and stroke.

    A lot of work has been invested into bone marrow stem cell therapy of spinal cord injury in the past few years. Many laboratories are studying bone marrow stem cell therapy of spinal cord injury:
    • Koshizuka, et al., (2004) reported that hematopoietic stem cells will improve recovery and show markers for astrocytes, oligodendroblia, and neural precursors but not neurons when transplanted into injured spinal cords of rats.
    • Sasaki, et al. (2001) and Akiyama, et al., (2002) and Kocsis, et al. (2002) reported tha bone marrow cells will promote myelination in demyelinated spinal cord.
    • Lee, et al. (2003) reported that mouse bone marrow mesenchymal stem cells will produce neurons or astrocytes in injured brains and spinal cords but they used an external marker bis-benzimide to label the cells; I am skeptical about any such marker because I think that these dyes spread and a much better way is to use genetic markers.
    • I am excited about Tuzynski's report (Lu, et al. 2004) that combination of neurotrophins, cAMP, and autologous bone marrow sstem cells will stimulate long-projecting dorsal-column sensory axonal regeneration.
    • Ohta, et al. (2004) recently reported that bone marrow stem cells injected through the fourth ventricle improved BBB recovery and reduced lesion volumes in rats after contusion injury and suggested that the bone marrow cells may exert trophic effects on acute spinal cord injury.
    • Zurita M and Vaquero J (2004) from Madrid reported that bone marrow stromal cells will form cell bridges at the injury site and express neuronal and astroglial markers, and improve BBB scores of rats with chronic spinal cord injury.
    • Wu, et al. (2003) report that bone marrow stromal cells promote differentiation of neurospheres in culture and promote regeneration of injured spinal cords, by reducing tissue damage associated with functional recovery.

    Several groups have reported that bone marrow cells do not transdifferentiate into neural cells in vivo (i.e. Castro, et al., 2002). I know that Itzak Fischer (2000) has been working for several years now transplanting bone marrow stem cells into injured rat spinal cords and have not found that these cells will produce neurons nor improve recovery after injury.

    References cited

    • McDonald JW, Becker D, Holekamp TF, Howard M, Liu S, Lu A, Lu J, Platik MM, Qu Y, Stewart T and Vadivelu S (2004). Repair of the injured spinal cord and the potential of embryonic stem cell transplantation. J Neurotrauma. 21: 383-93. Department of Neurology and Neurological Surgery, Washington University School of Medicine, St Louis, Missouri, USA. Traditionally, treatment of spinal cord injury seemed frustrating and hopeless because of the remarkable morbidity and mortality, and restricted therapeutic options. Recent advances in neural injury and repair, and the progress towards development of neuroprotective and regenerative interventions are basis for increased optimism. Neural stem cells have opened a new arena of discovery for the field of regenerative science and medicine. Embryonic stem (ES) cells can give rise to all neural progenitors and they represent an important scientific tool for approaching neural repair. The growing number of dedicated regeneration centers worldwide exemplifies the changing perception towards the do-ability of spinal cord repair and this review was born from a presentation at one such leading center, the Kentucky Spinal Cord Injury Research Center. Current concepts of the pathophysiology, repair, and restoration of function in the damaged spinal cord are presented with an overlay of how neural stem cells, particularly ES cells, fit into the picture as important scientific tools and therapeutic targets. We focus on the use of genetically tagged and selectable ES cell lines for neural induction and transplantation. Unique features of ES cells, including indefinite replication, pluripotency, and genetic flexibility, provide strong tools to address questions of neural repair. Selective marker expression in transplanted ES cell derived neural cells is providing new insights into transplantation and repair not possible previously. These features of ES cells will produce a predictable and explosive growth in scientific tools that will translate into discoveries and rapid progress in neural repair.

    • McDonald JW and Howard MJ (2002). Repairing the damaged spinal cord: a summary of our early success with embryonic stem cell transplantation and remyelination. Prog Brain Res. 137: 299-309. Center for the Study of Nervous System Injury, Spinal Cord Injury Restorative Treatment and Research Program, Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA. mcdonald@neuro.wustl.edu. Demyelination contributes to the loss of function consequent to central nervous system (CNS) injury. Optimizing remyelination through transplantation of myelin-producing cells may offer a pragmatic approach to restoring meaningful neurological function. An unlimited source of cell suitable for such transplantation therapy can be derived from embryonic stem (ES) cells, which are both pluripotent and genetically flexible. Here we review work from our group showing that neural precursor cells can be derived from ES cells and that transplantation of these cells into the injured spinal cord leads to some recovery of function. We have further examined and optimized methods for enriching oligodendrocyte differentiation from ES cells. ES cell-derived oligodendrocytes are capable of rapid differentiation and myelination in mixed neuron/glia cultures. When transplanted into the injured spinal cord of adult rodents, the neural-induced precursor cells are capable of differentiating into oligodendrocytes and myelinating host axons. The role of myelination and remyelination will be discussed in the context of regeneration strategies.

    • Koshizuka S, Okada S, Okawa A, Koda M, Murasawa M, Hashimoto M, Kamada T, Yoshinaga K, Murakami M, Moriya H and Yamazaki M (2004). Transplanted hematopoietic stem cells from bone marrow differentiate into neural lineage cells and promote functional recovery after spinal cord injury in mice. J Neuropathol Exp Neurol. 63: 64-72. Department of Orthopaedic Surgery, Chiba University, Graduate School of Medicine, Chiba, Japan. kossy-z@gb3.so-net.ne.jp. Recovery in central nervous system disorders is hindered by the limited ability of the vertebrate central nervous system to regenerate lost cells, replace damaged myelin, and re-establish functional neural connections. Cell transplantation to repair central nervous system disorders is an active area of research, with the goal of reducing functional deficits. Recent animal studies showed that cells of the hematopoietic stem cell (HSC) fraction of bone marrow transdifferentiated into various nonhematopoietic cell lineages. We employed a mouse model of spinal cord injury and directly transplanted HSCs into the spinal cord 1 week after injury. We evaluated functional recovery using the hindlimb motor function score weekly for 5 weeks after transplantation. The data demonstrated a significant improvement in the functional outcome of mice transplanted with hematopoietic stem cells compared with control mice in which only medium was injected. Fluorescent in situ hybridization for the Y chromosome and double immunohistochemistry showed that transplanted cells survived 5 weeks after transplantation and expressed specific markers for astrocytes, oligodendrocytes, and neural precursors, but not for neurons. These results suggest that transplantation of HSCs from bone marrow is an effective strategy for the treatment of spinal cord injury.

    • Sasaki M, Honmou O, Akiyama Y, Uede T, Hashi K and Kocsis JD (2001). Transplantation of an acutely isolated bone marrow fraction repairs demyelinated adult rat spinal cord axons. Glia. 35: 26-34. Department of Neurosurgery, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan. The potential of bone marrow cells to differentiate into myelin-forming cells and to repair the demyelinated rat spinal cord in vivo was studied using cell transplantation techniques. The dorsal funiculus of the spinal cord was demyelinated by x-irradiation treatment, followed by microinjection of ethidium bromide. Suspensions of a bone marrow cell fraction acutely isolated from femoral bones in LacZ transgenic mice were prepared by centrifugation on a density gradient (Ficoll-Paque) to remove erythrocytes, platelets, and debris. The isolated cell fraction contained hematopoietic and nonhematopoietic stem and precursor cells and lymphocytes. The cells were transplanted into the demyelinated dorsal column lesions of immunosuppressed rats. An intense blue beta-galactosidase reaction was observed in the transplantation zone. The genetically labeled bone marrow cells remyelinated the spinal cord with predominately a peripheral pattern of myelination reminiscent of Schwann cell myelination. Transplantation of CD34(+) hematopoietic stem cells survived in the lesion, but did not form myelin. These results indicate that bone marrow cells can differentiate in vivo into myelin-forming cells and repair demyelinated CNS.

    • Akiyama Y, Radtke C, Honmou O and Kocsis JD (2002). Remyelination of the spinal cord following intravenous delivery of bone marrow cells. Glia. 39: 229-36. Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06516, USA. Bone marrow contains a population of pluripotent cells that can differentiate into a variety of cell lineages, including neural cells. When injected directly into the demyelinated spinal cord they can elicit remyelination. Recent work has shown that following systemic delivery of bone marrow cells functional improvement occurs in contusive spinal cord injury and stroke models in rat. We report here that secondary to intravenous introduction of an acutely isolated bone marrow cell fraction (mononuclear fraction) from adult rat femoral bones separated on a density gradient, ultrastructurally defined remyelination occurs throughout a focal demyelinated spinal cord lesion. The anatomical pattern of remyelination was characteristic of both oligodendrocyte and Schwann cell myelination; conduction velocity improved in the remyelinated axons. When the injected bone marrow cells were transfected to express LacZ, beta-galactosidase reaction product was observed in some myelin-forming cells in the spinal cord. Intravenous injection of other myelin-forming cells (Schwann cells and olfactory ensheathing cells) or the residual cell fraction of the gradient did not result in remyelination, suggesting that remyelination was specific to the delivery of the mononuclear fraction. While the precise mechanism of the repair, myelination by the bone marrow cells or facilitation of an endogenous repair process, cannot be fully determined, the results demonstrate an unprecedented level of myelin repair by systemic delivery of the mononuclear cells.

    • Kocsis JD, Akiyama Y, Lankford KL and Radtke C (2002). Cell transplantation of peripheral-myelin-forming cells to repair the injured spinal cord. J Rehabil Res Dev. 39: 287-98. Department of Neurology, Yale University School of Medicine, New Haven, CT 06516, USA. jeffery.kocsis@yale.edu. Much excitement has been generated by recent work showing that a variety of myelin-forming cell types can elicit remyelination and facilitate axonal regeneration in animal models of demyelination and axonal transection. These cells include peripheral-myelin-forming cells, such as Schwann cells and olfactory ensheathing cells. In addition, progenitor cells derived from the subventricular zone of the brain and from bone marrow (BM) can form myelin when transplanted into demyelinated lesions in rodents. Here, we discuss recent findings that examine the remyelination potential of transplantation of peripheral-myelin-forming cells and progenitor cells derived from brain and bone marrow. Better understanding of the repair potential of these cells in animal models may offer exciting opportunities to develop cells that may be used in future clinical studies.

    • Lee J, Kuroda S, Shichinohe H, Ikeda J, Seki T, Hida K, Tada M, Sawada K and Iwasaki Y (2003). Migration and differentiation of nuclear fluorescence-labeled bone marrow stromal cells after transplantation into cerebral infarct and spinal cord injury in mice. Neuropathology. 23: 169-80. Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan. There is increasing evidence that bone marrow stromal cells (BMSC) have the potential to migrate into the injured neural tissue and to differentiate into the CNS cells, indicating the possibility of autograft transplantation therapy. The present study was aimed to clarify whether the mouse BMSC can migrate into the lesion and differentiate into the CNS cells when transplanted into the mice subjected to focal cerebral infarct or spinal cord injury. The BMSC were harvested from mice and characterized by flow cytometry. Then, the BMSC were labeled by bis-benzimide, a nuclear fluorescence dye, over 24 h, and were stereotactically transplanted into the brain or spinal cord of the mice. The cultured BMSC expressed low levels of CD45 and high levels of CD90 and Sca-1 on flow cytometry. A large number of grafted cells survived in the normal brain 4 weeks after transplantation, many of which were located close to the transplanted sites. They expressed the neuronal marker including NeuN, MAP2, and doublecortin on fluorescent immunohistochemistry. However, when the BMSC were transplanted into the ipsilateral striatum of the mice subjected to middle cerebral artery occlusion, many of the grafted cells migrated into the corpus callosum and injured cortex, and also expressed the neuronal markers 4 weeks after transplantation. In particular, NeuN was very useful to validate the differentiation of the grafted cells, because the marker was expressed in the nuclei and was overlapped with bis-benzimide. Similar results were obtained in the mice subjected to spinal cord injury. However, many of the transplanted BMSC expressed GFAP, an astrocytic protein, in injured spinal cord. The present results indicate that the mouse BMSC can migrate into the CNS lesion and differentiate into the neurons or astrocytes, and that bis-benzimide is a simple and useful marker to label the donor cells and to evaluate their migration and differentiation in the host neural tissues over a long period.

    • Castro RF, Jackson KA, Goodell MA, Robertson CS, Liu H and Shine HD (2002). Failure of bone marrow cells to transdifferentiate into neural cells in vivo. Science. 297: 1299. Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.

    • Fischer I (2000). Candidate cells for transplantation into the injured CNS. Prog Brain Res. 128: 253-7. Department of Neurobiology and Anatomy, MCP Hahnemann University, Philadelphia, PA 19129, USA. Itzhak.Fischer@drexel.edu.

    • Lu P, Yang H, Jones LL, Filbin MT and Tuszynski MH (2004). Combinatorial therapy with neurotrophins and cAMP promotes axonal regeneration beyond sites of spinal cord injury. J Neurosci. 24: 6402-9. Department of Neurosciences, University of California at San Diego, La Jolla, California 92093-0626, USA. Previous attempts to promote regeneration after spinal cord injury have succeeded in stimulating axonal growth into or around lesion sites but rarely beyond them. We tested whether a combinatorial approach of stimulating the neuronal cell body with cAMP and the injured axon with neurotrophins would propel axonal growth into and beyond sites of spinal cord injury. A preconditioning stimulus to sensory neuronal cell bodies was delivered by injecting cAMP into the L4 dorsal root ganglion, and a postinjury stimulus to the injured axon was administered by injecting neurotrophin-3 (NT-3) within and beyond a cervical spinal cord lesion site grafted with autologous bone marrow stromal cells. One to 3 months later, long-projecting dorsal-column sensory axons regenerated into and beyond the lesion. Regeneration beyond the lesion did not occur after treatment with cAMP or NT-3 alone. Thus, clear axonal regeneration beyond spinal cord injury sites can be achieved by combinatorial approaches that stimulate both the neuronal soma and the axon, representing a major advance in strategies to enhance spinal cord repair.

    • Ohta M, Suzuki Y, Noda T, Ejiri Y, Dezawa M, Kataoka K, Chou H, Ishikawa N, Matsumoto N, Iwashita Y, Mizuta E, Kuno S and Ide C (2004). Bone marrow stromal cells infused into the cerebrospinal fluid promote functional recovery of the injured rat spinal cord with reduced cavity formation. Exp Neurol. 187: 266-78. Department of Plastic and Reconstructive Surgery, Kyoto University Graduate School of Medicine, Shogoin, Sakyo-Ku, Kyoto 606-8507, Japan. The effects of bone marrow stromal cells (BMSCs) on the repair of injured spinal cord and on the behavioral improvement were studied in the rat. The spinal cord was injured by contusion using a weight-drop at the level of T8-9, and the BMSCs from the bone marrow of the same strain were infused into the cerebrospinal fluid (CSF) through the 4th ventricle. BMSCs were conveyed through the CSF to the spinal cord, where most BMSCs attached to the spinal surface although a few invaded the lesion. The BBB score was higher, and the cavity volume was smaller in the rats with transplantation than in the control rats. Transplanted cells gradually decreased in number and disappeared from the spinal cord 3 weeks after injection. The medium supplemented by CSF (250 microl in 3 ml medium) harvested from the rats in which BMSCs had been injected 2 days previously promoted the neurosphere cells to adhere to the culture dish and to spread into the periphery. These results suggest that BMSCs can exert effects by producing some trophic factors into the CSF or by contacting with host spinal tissues on the reduction of cavities and on the improvement of behavioral function in the rat. Considering that BMSCs can be used for autologous transplantation, and that the CSF infusion of transplants imposes a minimal burden on patients, the results of the present study are important and promising for the clinical use of BMSCs in spinal cord injury treatment.

    • Zurita M and Vaquero J (2004). Functional recovery in chronic paraplegia after bone marrow stromal cells transplantation. Neuroreport. 15: 1105-8. Neuroscience Research Unit of the Mapfre-Medicine Foundation, Neurosurgical Service, Puerta de Hierro Hospital, Department of Surgery, Autonomous University, Madrid, Spain. Previous reports showed the therapeutic effect of transplants of bone marrow stromal cells (BMSC) after incomplete traumatic spinal cord lesions. We studied the effect of this form of therapy in chronically paraplegic Wistar rats due to severe spinal cord injury (SCI). Rats were subjected to weight-drop impact causing paraplegia, and BMSC or phosphate buffered saline (PBS) was injected into spinal cord 3 months after injury. Functional outcome was measured using the Basso-Beattie-Bresnehan score until sacrifice of the animals, 4 weeks after transplantation. At this time, samples of spinal cord tissue were studied histologically. The results showed a clear and progressive functional recovery of the animals treated with BMSC transplantation, compared to controls. Grafted BMSC survived into spinal cord tissue, forming cell bridges within the traumatic centromedullary cavity. In this tissue, cells expressing neuronal and astroglial markers can be seen, together with a marked ependymal proliferation, showing nestin-positivity. These findings suggest the utility of BMSC transplantation in chronically established paraplegia.

    • Wu S, Suzuki Y, Ejiri Y, Noda T, Bai H, Kitada M, Kataoka K, Ohta M, Chou H and Ide C (2003). Bone marrow stromal cells enhance differentiation of cocultured neurosphere cells and promote regeneration of injured spinal cord. J Neurosci Res. 72: 343-51. Department of Plastic and Reconstructive Surgery, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, Japan. Transplantation of bone marrow stromal cells (MSCs) has been regarded as a potential approach for promoting nerve regeneration. In the present study, we investigated the influence of MSCs on spinal cord neurosphere cells in vitro and on the regeneration of injured spinal cord in vivo by grafting. MSCs from adult rats were cocultured with fetal spinal cord-derived neurosphere cells by either cell mixing or making monolayered-feeder cultures. In the mixed cell cultures, neuroshpere cells were stimulated to develop extensive processes. In the monolayered-feeder cultures, numerous processes from neurosphere cells appeared to be attracted to MSCs. In an in vivo experiment, grafted MSCs promoted the regeneration of injured spinal cord by enhancing tissue repair of the lesion, leaving apparently smaller cavities than in controls. Although the number of grafted MSCs gradually decreased, some treated animals showed remarkable functional recovery. These results suggest that MSCs might have profound effects on the differentiation of neurosphere cells and be able to promote regeneration of the spinal cord by means of grafting.

  5. #5
    Originally posted by DA:

    dr young you are always ragging on asc. finish the research before you dismiss them. all avenues must explored, right?
    DA,
    In my laymens mind I visualize or try to what all is written.
    After reading the published works oh maybe a hundred times.

    What my mind sees..and I want to compare that to what you see..why? Because sometimes I feel you see things that you don't say you just keep DAing on.

    I see an adult stem cell as just that..as grown up embryonic stem cell. Now in my mind I can't fathom it doing the job of an ESC.
    Why? Because evidently..not scientific of course..that same cell has stopped in it's original function..that of forming a spinal cord..a brain..a kidney.
    So..it only makes sense to me the advantage would be with the ESC that is still in holding of the program to make these cells not regenerate but generate.
    Sort of like a rookie lineman vs. a veteran..both know the job..but the veteran has run out of steam in performing it.

    What is shut off in the genetic makeup of these cells when they have accomplished their original purpose..to form the human body?

    Like with OEC's. Are they really regenerated cells are just duplications of the originals
    becoming less in quantity and usefullness as the duplication ages?
    Much alike skin..fat..and bone cells in general.

    So in my limited mind..it seems to capture the secrets of the embryo and utilize what is programed into it by evolution or God..I think God..would be the most effective way to deal with renewing non-functional cells..thus renewing the functions associated with those cells.

    Help is on the way.

  6. #6
    Senior Member DA's Avatar
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    Originally posted by Lindox:

    Originally posted by DA:
    dr young you are always ragging on asc. finish the research before you dismiss them. all avenues must explored, right?
    DA,
    In my laymens mind I visualize or try to what all is written.
    After reading the published works oh maybe a hundred times.

    What my mind sees..and I want to compare that to what you see..why? Because sometimes I feel you see things that you don't say you just keep DAing on.

    I see an adult stem cell as just that..as grown up embryonic stem cell. Now in my mind I can't fathom it doing the job of an ESC.
    Why? Because evidently..not scientific of course..that same cell has stopped in it's original function..that of forming a spinal cord..a brain..a kidney.
    So..it only makes sense to me the advantage would be with the ESC that is still in holding of the program to make these cells not regenerate but generate.
    Sort of like a rookie lineman vs. a veteran..both know the job..but the veteran has run out of steam in performing it.

    What is shut off in the genetic makeup of these cells when they have accomplished their original purpose..to form the human body?

    Like with OEC's. Are they really regenerated cells are just duplications of the originals
    becoming less in quantity and usefullness as the duplication ages?
    Much alike skin..fat..and bone cells in general.

    So in my limited mind..it seems to capture the secrets of the embryo and utilize what is programed into it by evolution or God..I think God..would be the most effective way to deal with renewing non-functional cells..thus renewing the functions associated with those cells.

    Help is on the way.
    funny thing about asc. those useless cells are bringing dead heart cells back to life after a heart attack.

    those useless cells have cured mice of MS.
    http://www.newscientist.com/news/news.jsp?id=ns99993638

    here is another article on those useless cells.

    http://www.wired.com/news/technology...,42761,00.html

    im already sure you wont read them because you
    like being a laymen.

  7. #7
    DA,
    Thanks for the links.
    I don't consider ASC as useless.

    Help is on the way.

  8. #8
    Hrmmm...

    [This message was edited by Steven Edwards on 10-13-04 at 05:08 PM.]

  9. #9
    Senior Member Rollin Rick's Avatar
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    Very interesting!!

    Time to ride not roll

  10. #10
    Sorry Rick... I was trying to post some links to information, but InfoPop appears to not be able to handle URLs with an open parenthesis in them.

    -Steven
    ...taking it back, I'm taking it back, taking back my life

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