Research Programs

The goals of this division are to translate our research work to new clinical treatments.  One of our primary aims is to concentrate on progressive disease.  This is because for the primary progressive form of the disease (PPMS), there are no FDA-approved treatments available and for the secondary progressive form of MS (SPMS), only mitoxantrone is an approved treatment.  Mitoxantrone, however, is rarely used because its use is associated with leukemia and it is cardiac toxic.  Based on approximately 10 years of work at Tisch MS and at our clinical affiliate IMSMP, we were able to publish a landmark paper on the use of Intrathecal Methotrexate treatment for SPMS and PPMS based on very exciting results in 121 patients.  This is the first paper on this treatment method and will form the basis of a new prospective study which will further define this novel form of the treatment.  We will apply for external funding for this planned study from Biogen and the MS Society.  
At present in the laboratory, we have two ongoing projects related to intrathecal methotrexate treatment.  In one project headed by Dr. Harris, a research assistant is examining about 30 spinal fluid “biomarkers” to determine which factors are associated with clinical response.  This is important because if these studies are successful, we will be able to predict which patients will best respond to this treatment within the progressive group.  In the second project supervised by Dr. Muller, a research assistant is investigating how this medicine works in progressive disease.  In early work it appears that methotrexate delivered directly into the spinal fluid (intrathecally) may reduce “sclerosis’ formation by inhibiting the cell proliferation of astrocytes (the cells responsible for scar formation in MS lesions).

Finding the Cause of MS

In 2006 we set our goal to find the cause of MS in five years.  So we have to find the cause this year! How close are we and what are we doing? Our approach is based on the finding that over 90% of MS patients have antibodies (oligoclonal bands) in spinal fluid.  These antibodies are not randomly present and it is known that they are produced within the brain and spinal cord and are closely related to each other, suggesting that they have a common target (that is what oligoclonal means).  These oligoclonal antibodies are important to study because in every condition other than MS in which similar antibodies are found, such as in measles, they are targeted toward the cause of the illness.  Thus, our assumption is that if we find out what these oligoclonal antibodies in MS are targeting, it will be the cause of MS or at the very least the key brain target protein (antigen).  This assumption is also based on certain immunological dogma.   When the immune system is “activated” and reacting to a specific target, the body produces select antibodies that are clones of each other to enable a highly specific and effective response.  This phenomenon is called clonal expansion and a persistent clonal response is highly suggestive of purposeful, targeted amplification of the immune system.  Thus, we aim to isolate clonally-expanded and persistent B-cells from patients with MS, mass produce them in the lab to allow detailed experimentation without repeated spinal taps, and determine their reactivity against all plausible targets.  Identification of this target should be the critical link to finding the cause of MS.
Jerry Lin, a B-cell molecular immune-biologist in our laboratory, along with his research assistants have accomplished the following in the past 5 or so years:
1) Using FACS analysis, they have been able to reliably isolate B-cells; 2) Using recombinant technology and sequencing, they have been able to determine which B-cells are clonally expanded and if spinal fluid is repeated at a later time point detect clonally expanded B-cells that persist; 3) They have isolated, sequenced and cloned single antibody producing cells from selected MS patients and a disease control (patient with HTLV-1 myelopathy).  The MS patients selected include two teenage patients with disease onset a few weeks prior to CSF collection; an unusual patient with radiological evidence of MS who has had no clinical manifestations as yet (pre-MS); a very early in disease PPMS patient, and two patients with long standing disease; 4) They have established somewhat surprisingly that the target antigen or initiating trigger is probably not present in brain or spinal cord.
We have made significant strides in this endeavor and are hopeful that in the next few months we will be able to identify the initial trigger of MS.  This is important because if identified, we can develop a “vaccination” approach that can prevent the development of MS.

Understanding the Mechanisms of Disease Progression

One of the most vexing problems in MS is to understand why some patients get worse or progress.  Put another way, a frustrated patient will frequently ask “why do all the FDA treatments work only for relapsing-remitting disease and not for primary progressive (PPMS) or secondary progressive (SPMS) forms of MS?” In the past year we have continued our work to better understand the mechanisms of disease worsening using three distinct approaches and have added a fourth new avenue of exploration as follows:
1) Dr.  Mueller and associates have continued their exploration of the cerebrospinal fluid cellular “message” to discover aspects that are uniquely associated with PPMS or SPMS.  This endeavor is based on the fact that every cell in the body has DNA that defines it and the DNA is produced by the reading or “transcription” of message from RNA based on the individual’s gene make up and their reaction to the disease.  Tisch MS’s unique set up and close proximity the IMSMP has allowed us to obtain and preserve all the RNA present in cerebrospinal fluid (CSF) in a patient prior to its degradation (a period of approximately 15 minutes).  The RNA or CSF “transcriptome” containing thousands of transcripts is analyzed to identify those that are either unique or altered in expression in progressive MS.  In work done over the past year, Mueller and his team of scientists are able to reliably differentiate between MS and control samples validating their approach.  In addition, they have identified a transcript that codes for hepatocyte growth factor (HGF) that is reduced in active MS.  We are currently investigating whether down-regulation of this protein is associated with progression and whether lower levels of HGF prevent optimal myelin repair.  
2) Dr. Cristofanilli and his group are trying to determine if an experimental model can be created that allows for pathological analysis of the disease mechanisms pertaining to progressive tissue.  They have already established in cell experiments that CSF from PPMS and SPMS patients contain cellular products that determine disease and stimulate repair pathways.  In pilot data they have shown that CSF derived from patients with progressive disease injected directly into the CSF-containing spaces of a mouse brain (ventricles) leads to typical MS lesions remote from the site of injection in areas of the spinal cord ( a site of disease predilection in progressive disease).  This is an extremely exciting finding and is an original discovery.  Confirmatory experiments are currently being performed and will for the first time allow an animal model based on human pathology to be investigated.  In addition, this also has the potential of allowing the development of therapeutic strategies specifically directed at progressive disease.  
3) Dr. Brydon and colleagues have been comparing the immune profiles of treatment-unresponsive progressive disease patients with those of long duration completely benign patients who have no disability.  We are doing this because immune mechanisms are universally regarded as being important in the pathogenesis of MS.  Dr. Brydon hypothesizes that comparison of these two distinct populations of patients at the opposite ends of the MS disability spectrum will help identify the critical immunological factors associated with disease progression.  In preliminary work, they have shown that high levels of CSF TH1 producing gamma interferon cells occur in patients with severe disease and in contrast, patients with “benign” disease have upregulated FoxP3+ regulatory T cells.  This suggests that in benign patients, the body’s regulatory system promotes self tolerance and in patients with progressive disease, the innate controls on self tolerance are dysfunctional.  Ongoing studies are looking at all other immune cell types and at their cellular products such as cytokines and chemokines.  Upon completion of these critical studies, we may be in a position to recognize early in the disease patients who are destined for a poor outcome.  This would allow therapeutic intervention of appropriate aggressiveness to be implemented prior to the development of irreversible disability.  
4) Our newest avenue of research has resulted from the recruitment of Dr. Mir from University of Illinois, Chicago who joined Tisch MS in March 2011.  Her expertise in cellular oxidative stress has led to initial studies in looking at isoprostanes and other oxidative stress biomarkers in patients with progressive disease.

Repair strategies in MS

There are no existing therapies that are capable of repairing the myelin and nerve damage that exist in MS. Dr. Harris and her team focused on adult stem cells from the bone marrow, called mesenchymal stem cell-derived neural progenitors (MSC-NPs), which have the potential to stop or reverse progression in MS. These cells have the advantage that they can be taken from the patient’s own bone marrow, expanded in number in the laboratory, and reinjected back into the spinal fluid. Over the past year, our work has made significant strides and we have now unequivocal data in experimental MS models of disease amelioration and decreased demyelination associated with this stem cell therapy.  In addition, we have shown that the mechanisms involved include induction of a tolerant CNS milieu as well as induction of resident host stem cell progenitors to differentiate.  An investigational new drug application has been submitted to the FDA, but is currently on clinical hold pending additional safety studies to be done in a larger animal model such as a rabbit.  This is going to require additional funding and time.  However, we are continuing our laboratory effort of optimizing repair strategies.  These include studies looking at creating a growth environment in which infused stem cells will flourish and also looking at optimal ways to deliver cells to injured tissue and enable cell migration, growth, and differentiation.  In parallel studies, Dr. Cristofanilli and associates are also working on animal models of tissue repair with other stem cell populations.