Note to Lafora Parents - From the Doctors
Parents,
We would like to make sure that all patients have had their data recorded in our central files and that we are aware of your child's mutation information.
If you are not sure your child’s Athena lab results are in Dr. Berge Minassian’s database at The Hospital for Sick Children in Toronto please email: jadestone81@hotmail.com
In the subject line or body of the email, please mention that you are sending us your mutation information from the chelseashope.org website.
Thank you,
The Lafora Research Team
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January 4, 2009
Dr. Antonio V. Delgado-Escueta and his team are developing two treatment approaches, including 1) gene therapy for all Lafora disease patients, and 2) gentamicin treatment for those patients with nonsense mutations.
1) Gene therapy
The stellate electroencephalography (EEG) machine arrived on November 19, 2008, and the team started EEG recordings on mice the same afternoon. With the new EEG machine, Dr. Escueta now has the capability to monitor the effects of gene therapy on seizures and epileptic form discharges. Expenses include supplies for the EEG machine, a new stereotactic apparatus to measure exact electrode placement, and monthly costs for the mice colony.
Dr. Escueta is now prepared to hire a scientist focused on the gene therapy approach who is trained in mice research models as well as molecular biology. The annual salary for such a researcher is $80,000 a year.
2) Gentamicin treatment
Dr. Escueta and his team have now organized a team of five specialists to execute the protocol. In addition, Dr. Escueta has secured a bio-safety team with three members to oversee the project. We have asked Dr. Paul Beringer, a pharmacokinetics/pharmacologist specialist from the University of Southern California, to participate as a co-investigator. He will be the newest member of the team. Dr. Beringer has extensive experience with gentamicin treatment for cystic fibrosis.
Future funding will be used to absorb a portion of the salaries for the treatment team and safety/oversight committee members. Funding also will support the costs associated with patient treatment, both inpatient and outpatient at the General Clinical Research Center (UCLA-GCRC) where the gentamicin will be administered.
Another Research Perspective
The problem facing a Lafora patient is the conversion in brain cells of normal glycogen, a soluble sugar, into a starch-like insoluble sugar. This insoluble compound accumulates in the brain cells and devastates their function. How and why this happened was a great mystery until recently. We have now discovered that the problem is that normal glycogen in the Lafora patients acquires excessive phosphate, and that it is this phosphate that distorts normal glycogen and makes it become starch-like and insoluble. We now are trying very hard to uncover where this excess phosphate comes from, and then we will try to prevent this, or find ways to remove it so as to re-normalize the glycogen and keep it from precipitating and accumulating. If we can do this, we can treat or cure our patients. How long the way is from this point towards a treatment we do not know, but we now know we are on the right track”.
--Dr. Minassian
A BRIEF OVERVIEW OF LAFORA DISEASE
Lafora Disease is an inherited myoclonus epilepsy syndrome. Most cases of Lafora disease are caused by mutations in one of two known genes: EMP2A and EMP2B. Both genes are located in chromosome 6. The gene EPM2A makes the protein called Laforin and the gene EPM2B makes the protein called Malin. A few cases of Lafora disease are caused by an as yet unidentified gene(s). Lafora disease causes seizures, muscle spasms, difficulty walking, dementia, and eventually death.
The disease most commonly starts as epileptic seizures in adolescence. Rarely, it begins in 5 to 6 year old children as a learning disorder. There is a higher incidence of the disease in children of Middle Eastern, Southern European (Spain, France and Italy), South Asian (India and Pakistan) and North African descent. The disease appears to affect males and females equally.
There is currently no therapy that has proven effective against disease progression. Therapy is primarily palliative and aimed at reducing seizures.
We are raising funds for two forms of treatment on the horizon, one on the immediate horizon is gentamycin treatment and the other on the near horizon is called gene replacement treatment using pegylated immunoliposomes (PIL). Note: Any trials that are considered “research” will first require review and approval by an Institutional Review Board (Human Subjects Protection Committee) and this can take considerable time and coordination by someone on the team.
Lafora Disease currently receives very little, if any, funding from the Federal Government; perhaps because the disease is extremely rare in the United States. It is currently unknown how many children in the United States suffer from Lafora Disease. Although it is a rare, “orphan” disease, we are determined to find a cure for Chelsea’s hope and the hope of other children with Lafora Disease in other parts of the world.
Symptoms
Lafora Disease symptoms usually appear in the late stages of childhood and early adolescence. In most cases, patients develop normally for roughly the first ten years of their life. The first symptom to usually manifest is called a tonic-clonic seizure, a seizure that affects the entire body. Tonic-clonic grand mal seizures are characterized by extreme muscle tension and rapid muscle contractions. In other cases, the first symptom may be a seizure, induced by flickering light, characterized by staring for 1-10 seconds (absences or petit mal seizures) with momentary loss of responsiveness and a disconnection with the surrounding environment. Eventually, all develop the characteristic lightning-like muscular jerks that shake the shoulders, arms, legs or body and face. Such quick myoclonic spasms can affect a fragment of muscles in arms and shoulders on one side or both sides of the body and are triggered by touch, light or sound, appear almost continuously and are the reason for calling Lafora Disease a myoclonic epilepsy. Other symptoms include temporary blindness, visual hallucinations, depression, diminishing performance in school, ataxia (difficulty walking), and dementia.
In general, the following are symptoms that may indicate possible Lafora disease. If your child begins to demonstrate the combination of the following symtoms, immediately speak with your child's doctor about Lafora Disease and about having a skin biopsy and mutation analyses.
- Tonic-clonic seizures (full body seizures)
- Flickering-light induced absence and myoclonic seizures
- Reports of temporary blindness
- Visual hallucinations
- Depression
- Unexplained diminishing academic performance
- Difficulty walking (ataxia)
- Problems in thinking (Dementia)
Both skin biopsy and mutation analyses are necessary to prove lafora disease.
Why Skin Biopsy:
Biopsy of sweat glands in the axilla (arm pit) should show the disease causing inclusion bodies that stain with PAS (periodic acid schiff) inside eccrine sweat duct cells or apocrine myoepithelial cells located in the arm pits. These inclusion bodies are made of abnormally branched glycogen called polyglucosan and was originally discovered by Gonzalo Lafora in the patients’ brains. This separates Lafora Disease from other progressive myoclonic epilepsies. The presence of PAS+ inclusion bodies means you (your child) have Lafora Disease. If the skin biopsy is negative but you (your child) still have the above symptoms of Lafora Disease, it is reasonable to get a muscle or liver biopsy.
Why Mutation Analyses:
There are two reasons for mutation analyses.
First, PAS+ inclusion bodies may be present in your skin biopsy but mutations in EPM2A or EPM2B are absent. This means you have the rare form caused by an as yet unidentified gene.
Secondly, it is now important to find out if the forms of mutations present are nonsense mutations. Nonsense mutations may respond to gentamycin treatment.
Words From One of Our Researchers
We essentially breathe, sleep, dream and ceaselessly work on this disease. Our hope is to understand it so fully that we can come up with a treatment. My personal dream is this: Next time a Matt or a Jessica or an Amanda is brought to a neurologist, and the diagnosis of Lafora is made, the doctor would simply write a prescription and say: you have Lafora, take this, all will be alright.
Based on the genes, we have found the proteins disturbed in this disease and we are now painstakingly finding all the interacting proteins and step by step reconstructing the biochemical pathway that is disturbed. We are certain that with understanding will come insights into the cure.
Lafora patients form Lafora bodies in their brain cells, which cause the horrible epilepsy these patients suffer from. In parallel to unraveling the disease processes that lead to Lafora body formation, we are designing a method to remove them from the brain, and return the patient to normalcy. We know that amylase, the starch-digesting enzyme in saliva, can digest Lafora bodies. We are working on a method to introduce amylase into neurons to melt the Lafora bodies away and cure our patients.
The hurdles are many and the work is large, but so is our commitment. The disease is rare, and hard to find government funding for. We therefore count on you.
- Berge Minassian, MD.
Research Overview
Lafora Disease receives practically no funding from the Federal Government or other organizations due to its limited occurrence in the United States. The disease is classified by the Federal Government as an "orphan disease," thus being ineligible for funding available to more prevalent diseases. Fortunately, rapid advances in the biochemistry of glycogen metabolism have occurred stimulated by the discovery of the disease causing genes EPM2A (Laforin) and EPM2B (Malin). These advances have set the stage for the development of treatment protocols and the development of assays to monitor such treatment protocols.
We seek to raise money through contributions to help fund research about these specific treatment protocols and monitoring assays. Please visit the subpages of the research section to learn more about what is going on in Lafora Disease research and to learn more about what we need to do to help combat this disease.
RESEARCH DEVELOPMENTS -- The Lafora Disease Story So Far
MYSTERIES OF BRAIN METABOLISM AND LAFORA DISEASE
One of the mysteries of brain metabolism and for that matter Lafora Disease is why normal nerve cells do not store glycogen. Glucose is the main source of energy in the brain as in other cells and glycogen is the main storage for glucose. Hence glycogen is a source for chronic energy and yet glycogen is not present in normal nerve cells. In contrast, in Lafora Disease, a progressive and deadly form of epilepsy, excessive amounts of abnormally branched glycogen accumulate in toxic amounts and kill nerve cells. This suggested that there must be finely-tuned machinery in the brain that prevents glycogen from appearing much less accumulating in normal nerve cells. This mystery is rapidly being solved by expert biochemists in glycogen metabolism and protein phosphatases spurred on by the discoveries of the disease causing genes in Lafora Disease by clinician scientists. This separate group of scientists has worked furiously, independently but harmoniously, in the last 12 years. In spring of 2007, these scientists met for a Workshop in Sarlat, France, stimulating collaborations, speeding up research, triggering a spate of publications and helping set up the stage for treatment protocols in Lafora Disease.
Finding the Disease Causing Gene of Lafora Disease
The modern story of Lafora Disease started in 1995 in the Epilepsy Genetics/Genomics Laboratories at the Epilepsy Center of Excellence of the Greater Los Angeles VA Medical Center and the David Geffen School of Medicine at UCLA. There, the first chromosome locus (6p24) for Lafora Disease was discovered. This led to the eventual identification of EPM2A (Laforin) in 1998 and EPM2B (Malin) in 2003 by the Los Angeles scientists and previous PhD and postdoctoral students who had then branched out into their own independent laboratories in Toronto (Canada), Madrid (Spain) and Kanpur (India). The families being studied by the Lafora Disease researchers then showed that Laforin belonged to a group of enzymes called dual specificity phosphatases that targeted glycogen while Malin was an E3 ubiquitin ligase, an enzyme involved in the cell disposal unit (like the garbage disposal of a kitchen). By 2002, two mice models of lafora disease were made -- one where the laforin gene was knocked out in the developing embryo was made by collaboration between Los Angeles and Japanese scientists. Another, where a mutation of laforin was inserted in the developing embryo was prepared by Toronto scientists.
Setting the Stage for Laforin Gene Replacement Treatment
Enter the scientist experts on protein phosphatases and glycogen metabolism. First to help in 2005, was the protein phosphatase lab at UC San Diego which showed that EPM2B/malin actually tagged EPM2A/Laforin with a marker (ubiquitin) and set it on its way to the cell disposal unit. In the ensuing two years, the same group of scientists from UC San Diego and Norwich, UK, together with plant biologists in Austria, discovered the counterpart of Laforin in plant and other organisms and showed that humans and other organisms share the common function of laforin in purging excessive carbohydrates and glycogen and preventing glycogen buildup that is harmful to the plant and organism cells. Next came the experts on glycogen metabolism. In 2007, a consortium of scientists from Madrid, Barcelona and Valencia, confirmed by the same UC San Diego team, showed that a complex of Laforin and Malin acting together suppresses the enzyme machinery that makes glycogen in nerve cells. The same complex of Laforin and Malin also sets up for the cell disposal unit the Laforin docking regions for protein phosphatase-1 and glycogen synthase (enzymes necessary for making glycogen). This way, the Laforin-Malin complex ensures suppression and blockade of glycogen formation in nerve cells as well as elimination of glycogen and its necessary enzymes by the cell disposal unit. When nature places a mutation in either Laforin or Malin, not only is poorly branched glycogen formed in excess but elimination through the cell disposal unit of glycogen and its components and its control systems by the Laforin/Malin complex is also dysfunctional and nerve cells die.
Also in 2007, both UC San Diego scientists and Indiana University scientists independently demonstrated that Laforin could release phosphate from amylopectin, a plant carbohydrate similar to glycogen and actual mammalian glycogen. This is very important because it shows for the first time that glycogen like amylopectin is a substrate of Laforin. If Laforin acts as a glycogen phosphatase in vivo, then the phosphate content in glycogen would be elevated in Lafora Disease. This is what is found in the mice whose Laforin has been knocked out. Glycogen phosphatase assay could, thus, provide a way of monitoring treatment.
Blood Brain Barrier Experts in the Epilepsy Center of Excellence at Los Angeles
As the functions of Laforin and Malin were unraveling, so the mysteries of glycogen metabolism were being demystified. Meanwhile, a team of experts on the blood-brain barrier in Los Angeles started to devise a method to deliver Laforin from the blood through the blood-brain barrier into brain nerve cells of mice with Lafora Disease. If the function of Laforin is to purge glycogen from nerve cells, then delivering Laforin into the brain of Lafora Disease patients would clear the brain of Lafora inclusion bodies. Starting in 2002, these scientists in Los Angeles labored through the details of placing Laforin inside a vehicle that should be harmless to humans, namely, pegylated immunoliposomes. (Placing Laforin inside lipids contrasts to placing the gene inside adenoviruses which have now been suspected to cause death in 2 persons and possible leukemia in 2 children.) By 2006, Laforin delivered by immunoliposomes into brains of mice with Lafora Disease was shown to indeed purge and decrease the load of Lafora inclusion bodies. Now, the timing of delivery, the exact doses, the frequency of delivery, and the interval of delivery of Laforin are being fine-tuned in mice with Lafora Disease. All this information will be important when Laforin is actually delivered to patients with Lafora disease.
Monitoring Results of Laforin Gene Therapy
One other advantage gained from defining glycogen and amylopectin as substrates of Laforin is the deduction that the Lafora inclusion bodies must be made of poorly branched glycogen. This could allow the imaging of Lafora inclusion bodies in patients suffering from the disease using a positron emission labeled chemical that is part of Lafora inclusion bodies. This would be an important project for chemists -- to produce a ligand that targets a part of lafora inclusion bodies and that could be imaged on PET scans. This can be another way for monitoring the results of treatment. If Laforin can really purge excessive glycogen like the Lafora inclusion bodies, then we should be able to show the inclusion bodies decrease and even disappear on PET scans that image Lafora bodies.
Where is the Story of Lafora Disease Leading us
This story is taking us to the treatment protocols and studies that need to be developed and developed rapidly if we are to save lives. Besides laboratory work and collaborations with various experts, this involves applications to the Institutional Review Boards to obtain approval for treatment in patients.
Thus, funds are urgently needed to develop a treatment team for Lafora Disease. This treatment team should address the following:
(1) A treatment team dedicated to
- A safety trial of laforin gene therapy in non-human simians
- Laforin human gene therapy and
- Gentamycin treatment
(2) An assay team that monitors gene replacement treatment results
(3) A PET scan team that assays turnover and purging of Lafora bodies during gene replacement treatment
