Results 1 to 2 of 2

Thread: Spinal Cord Research Update

  1. #1
    Senior Member Duran's Avatar
    Join Date
    Jul 2001
    Location
    Maximum security prison, Death row
    Posts
    441

    Spinal Cord Research Update

    Here is a link: http://www.lionsclubtraralgon.asn.au/scr.html


    INTERNATIONAL RESEARCH NEWS:

    It has been quite some time since our last update and we apologise to regular readers. Whilst progress is accelerating, interesting news is hard to come by.

    If you would like to make suggestions about our page, please email our project chairman at spinal@lionsclubtraralgon.asn.au or the site editor HERE.

    SCS Laboratory - Fort Collins

    The following is an update on general activities at the SCS Centre at Fort Collins. Progress is rapid and accelerating.

    Centre Changes

    In June 2002, the Spinal Cord Society Research Centre changed directorship from the control of Dr. Howard Nornes to Dr. Jesse Owens and Dr. Eric Holmberg.

    At the moment, besides Drs. Owens and Holmberg, three Ph.D. level scientists and two technical individuals staff the Research Center. Dr. Tuija Nordstrom is responsible for the cell culture facilities and has assumed a great number of the general lab managerial duties. Dr. Aksel Soosaar has maintained his focus on matters of biochemistry and gene delivery and he is assisted by Sirje Soosaar. Dr. Lisa Siconolfi has been primarily responsible for surgeries and general histology. She has been assisted by Mica Gross.

    Dr. Siconolfi has decided to move on to different ventures in her life. Before her departure she was instrumental is executing the stem cell transplant studies begun with Dr. Nornes. Dr. Siconolfi spent a great deal of her time harvesting samples from these transplant studies and preparing the tissues for analysis. The samples are presently being analysed for viability and integration. The research centre is presently searching for her replacement and additional scientists and technical help.

    Dr. Soosaar has begun a new project in which he has constructed a gene delivery vehicle that has been coated with a peptide, or piece of a protein that causes the uptake of the vehicle into the cell. This process involves the synthesis of several lipid species and the attachment of the components to the surface of the delivery vehicle. Preliminary results indicate that the syntheses were successful and that lipid vehicles were formed. Researchers proceeded by examining the binding of these vesicles to cells in culture and examining their binding to the cell. The results indicate that they have a very competent vehicle that has a very high binding component to these cells. They have also undertaken a series of experiments that involve introduction of these vehicles to the brain and spinal cord in animals. Researchers will examine the binding, distribution, and bioactivity of gene and protein products in the central nervous system - in the hope this represents progress in the delivery system.

    Dr. Quentin Reuer of the University of Alaska, Anchorage visited the research centre to demonstrate a series of techniques to the staff. These included the isolation and amplification of RNA. In addition, Dr. Reuer demonstrated a technique in which slices of the spinal cord can be isolated and kept alive in culture. This technique will be very helpful in examining neurite outgrowth and response to enzymatic and inhibitor treatments. All of the staff participated in these experiments in order to coordinate the eventual treatment protocols. Briefly, spinal cords were excised from foetal rats. These cords were placed in a soft gel matrix and were very thinly sliced. The slices were microsurgically trimmed and treated to grow in culture. The slices can be kept viable for a substantial period of time and researchers will be able to observe the growth and response of the treatments under the microscope.

    In addition to the isolation of spinal slices, the lab began the perfection of techniques to isolate neurons from the brain and spinal cord and the isolation of olfactory ensheathing cells.

    The Research Centre is expanding. SCS has obtained additional space in the building that houses the lab. They have constructed an accessible office for Dr. Owens and are beginning to remodel the space to accommodate an electrophysiology laboratory and RNA isolation station. This new space will allow them to expand the technical base of the Research Centre. These techniques are necessary to answer important questions such as whether a transplanted cell is electro physiologically competent after integration in the tissue.

    Recent Research Developments


    Alongside with the change of the Centre's directorship, a new approach has been added to the scientific work. The problem they aim to solve is still the same: chronic spinal cord injury. Also remaining unchanged is the preference they see in a combination treatment that merges a few successful experimental systems. Only the way to tackle the problem has changed.

    From neural precursors to olfactory ensheathing glia:

    The neural precursor cells that are grown in the Centre laboratory originate from adult post-mortem brain. To isolate these cells, one whole olfactory bulb was used. The access to the olfactory bulb is limited and requires a major operation. Other sources for the adult neural precursor cells have been reported: The cells can be recovered from smaller biopsies removed at the time of a brain surgery from adults.

    There is another possibility to gather samples of cells that have been reported to support functional recovery after spinal cord injury. The olfactory ensheathing cell is a special type of glia that shares characteristics with astrocytes and Schwann cells. The olfactory glia is found, as the name indicates, in the olfactory bulb (OB) - In addition, the olfactory ensheathing cells have been found in the nasal cavity from where they extend toward the OB. Their biological role is to support growing axons of the olfactory receptor neuron that are born in the nasal cavity epithelium and send their axons to the OB in the brain. Olfactory ensheathing cells secrete neurotrophic factors into their surroundings and by doing so they support neuron survival. In addition, molecules known to promote neurite initiation, attachment, and growth are associated with the olfactory ensheathing cells. These cells can be separated from the OB astrocytes by their specific cell surface-protein expression pattern.

    The number of cells that can be isolated from a nasal cavity is not very high. A second problem associated with the isolation and propagation of these cells is their limited growth in vitro. During the past few months, the centre has worked in the isolation and propagation of the olfactory ensheathing cells from adult rats OB's. Although these cells seem to be highly sensitive to the time that passes before the cells are plated in their growth medium, researchers have succeeded to get the first initial short term cultures to grow. But, the purity of these cultures is still not optimal. Immunocytological staining of the cultures have shown the presence of numerous candidates for olfactory ensheathing cells but also the presence of few fibroblasts and astrocytes. Whilst other laboratories use more sophisticated methods to separate the olfactory ensheathing cells from the contaminating cells, SCS researchers see the separation problem being a minor problem to be solved.

    More work needs to be done to achieve a long-term continuous growth in the primary olfactory ensheathing cell cultures.

    The work with the neural precursor cells has revealed a great number of valuable data that can be applied to the new extended research about a supporting cell type. Although the neural precursors share few similarities with the olfactory ensheathing glia, most importantly both cell types support the host to self-repair by secreting neurotrophic factors and by laying out a non-inhibitory pathway for regenerating axons. The greatest advantage with the olfactory ensheathing glia is its safe nature as an already committed cell type, in comparison to the plasticity of a stern cell that to a great extent responds to the micro-environmental signals. However, there is one great advantage that only the neural precursor cells do provide: their capacity to form new neurons. These newborn neurons compose around 50% of all the differentiated human precursor cells on a culture dish. Thus, these cells could be used to replace lost neurons or even build new compensatory functional neural networks.

    Glossary

    Astrocytes - A supportive cell type of the central nervous system that is not electrically active.

    Fibroblasts - Cell type of connective tissue Normally not found inside the CSN but will be part of the glial scar that is formed after trauma.

    in vitro - Any biological process studied outside of the organism (literally "in glass").

    Nasal cavity epithelium defined "on of the roof of the nasal cavity that limbers stem cells for sensory neurons and olfactory ensheathing cells.

    Neural precursor cells - The young cell that has committed to a neural lineage but is still not terminally differentiated.

    Olfactory bulb (OB)--A part of the brain that receives signals from the nose.

    Olfactory ensheathing cell - A Special type of macroglia that ensheaths sensory neuron axons and support their growth from PSN (nasal cavity epithelium) to the CSN (olfactory bulb).

    Olfactory receptor neuron - A sensory cell that mediates sense of smell. These cells are renewed throughout the life and are able to grow their axons from the nasal epithelium to the olfactory bulb.

    Copyright SCS 2002 AD rights reserved

  2. #2
    Senior Member Leo's Avatar
    Join Date
    Jul 2001
    Location
    Yankton, South Dakota
    Posts
    4,005
    Good post Push,

    Great info for a slow reluctant learner like myself.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •