Tag Archive for: research

Research “Development of exon excision therapy”

LEES ARTIKEL IN NEDERLANDS

This study aims at permanently removing specific exons, which include hereditary mutations when patients are concerned, from the DNA of the photoreceptors in the retina and/or the hair cells of the inner ear with the help of the CRISPR/Cas9 gene editing technique. The objective of this strategy is to stop the deterioration of eyesight (and hopefully in the longer term that of hearing as well) with larger groups of patients who have mutations in these exons of the USH2a gene with a one-off treatment.

Dr Erwin van Wijk and his colleague Dr Erik de Vrieze (both working at Radboudumc) will study the effect of a new strategy for treating Usher Syndrome. The research group of these scientists will cooperate with Vasiliki Kalatzis of the University of Montpellier in France and apply the CRISPR/Cas9 in this study.

Development of exon excision therapy
Exon excision is a new treatment strategy for modifying genes that code larger structural proteins consisting of chains of repetitive protein domains. These protein domains are the functional parts within a protein. The idea is that a protein can do without one or more of these domains without losing its function. This can be compared with a chain. A large number of separate links that individually look the same together forms a chain. When a few links are taken out, the chain will indeed become a bit shorter, but it will still be functional.
At least four of the known Usher Syndrome-related proteins, being usherin (USH2a), ADGRV1 (USH2c), cadherin23 (USH1d) and protocadherin15 (USH1f), consist of a chain of repetitive ‘links’, called protein domains. Using the molecular pair of scissors ‘CRISPR/Cas9’, the genetic regions in the USH2a gene that code for such a repetitive protein domain and which also include hereditary defects when patients are concerned will be permanently removed from the DNA of photoreceptors. This will shorten the USH2a protein by one or more ‘links’ and the study is meant to find out whether it will still be functional. Mutations in the genes related to USH2a, USH2c, USH1d and USH1f together account for the underlying cause in as many as 75% of all Usher Syndrome patients! This emphasises the potential of this therapeutic strategy.

Jorden Leuverman: “It is particularly great to know that the interview has also resulted in something much bigger than just my sponsor campaign”

Personal involvement
It was an article in the Tubantia, which caught the eye of Inge Wessels. In the newspaper there was an interview with Jorden Leuverman in which he told about living with Usher Syndrome. Inge Wessels: “I was deeply touched. Jorden was very hard of hearing already and he would also slowly lose his eyesight.” Jorden was diagnosed with Usher Syndrome, just like his grandfather was. As Jordan knows the impact of this, he started a sponsor campaign for the Usher Syndrome Foundation. Together with his running buddy he participated in the footrace in Zutphen, the Netherlands, and with this collected € 5000.- for the Usher Syndrome Foundation, hoping that there will timely be a treatment for Usher Syndrome.
Inge Wessels: “When I read the interview in the newspaper, I felt such a deep respect for this man. I know from experience what it means to be deaf in daily life. Much information can be received by looking at the mouths of people talking and other non-verbal communication. When Usher Syndrome takes away your eyesight as well, I think this is really terrible.”

Can I help?
Inge Wessels supported the sponsor campaign of Jorden and also made a donation to Stichting Ushersyndroom. “Can I help you with the funding of a promising study?” Inge Wessels asked early this year.
Jorden: “I hoped to collect as much money as possible for Stichting Ushersyndroom with my sponsor campaign. This amount suddenly became a lot higher thanks to the fact that I was interviewed by a reporter of the Tubantia newspaper. It is particularly great to know that the interview has also resulted in something much bigger than just my sponsor campaign.”

Stop the process of becoming deaf and blind
About 400.000 people globally suffer from Usher Syndrome, of which about 1.000 in the Netherlands. Faults in about ten different genes lead to Usher Syndrome. These genes code for proteins that are crucial for the functioning of the eyes and the ears. At this moment, there still is no treatment for any type of Usher Syndrome that can slow down, stop or recover the process of becoming both deaf and blind.

Reggeborgh supports research the 4-year study ‘Development of the exon excision therapy’. We are really grateful to the Reggeborgh for its donation for this promising study!

f.l.t.r. Shannon Leuverman, Erik de Vrieze, Ivonne Bressers, Jorden Leuverman, Erwin van Wijk

New type of Usher Syndrome discovered: USH IV   

LEES ARTIKEL IN HET NEDERLANDS

The team of the Hearing & Genes Expert Centre of Radboudumc lately made a discovery: Usher Syndrome includes four different clinical types. The researchers, with Hedwig Velde as principal author, recently published their study and findings in the leading Human Genetics. With the identification of minor faults (mutations) in the ARSG gene and the description of a new clinical picture, they confirm the discovery of a fourth type of Usher Syndrome. 

This really is an important discovery, which gives more clarity about a number of patients with atypical Usher complaints without a genetic diagnosis. In the meantime, following the identification of ARSG as Usher gene, globally fifteen people have still been diagnosed, now that they all appear to have mutations in the ARSG gene. As it has been demonstrated that these patients have a common pattern of symptoms, this is no longer an atypical picture, but it makes up a new clinical type.       

A patient with an atypical clinical picture
Very rarely a patients visits the outpatients’ clinic showing symptoms that correspond with the clinical picture of Usher Syndrome (loss of hearing combined with retinitis pigmentosa), but which picture deviates from the familiar Usher types. This is called an atypical clinical picture. In some cases no generic cause is found in the Usher genes that are known so far. Consequentially, these patients are unfortunately sent home again without having been diagnosed (and without any clarity). 

Hedwig velde

 Hedwig Velde is researcher and doctoral candidate at the ENT section Hearing & Genes of the Radboudumc. She is studying patients who suffer from loss of hearing but who have not been genetically diagnosed. With her research team she confirmed a new Usher Syndrome type, which is caused by minor faults in the ARSG gene.  

A publication from the year 2018 written by a group of scientists in Israel described the discovery of the ARSG gene with Arylsulfatase G as a protein that might be involved with Usher Syndrome. The researchers from Israel described five persons from three families who all had the same minor fault in the ARSG gene. Such a publication may give other researchers ideas for their studies.  

Studying the DNA of several people within one family sharing the same symptoms is a big help for scientists. Hedwig Velde: “There is a big chance that all patients within the family share the same genetic cause. When outside the family that has been studied another patient is found with the same atypical clinical picture and a minor fault in the same gene, this may confirm the relation between the gene and the clinical picture. Of course, the chance of coming across this patient is really small. Usher Syndrome is very rare.”  

Until the national Expert Centre in the Radboud UMC saw a patient with this atypical clinical picture of Usher Syndrome and Hedwig Velde and other researchers in the Radboud UMC continued the study that was started by the team in Israel in 2018.    

New type now confirmed
With the publication of Hedwig Velde c.s. the researchers confirmed this new type. The researchers found minor faults in the same gene (the ARSG gene), which creates the codes for the Arylsulfatase G protein. This protein is involved in the degradation of another protein and the idea is that malfunctioning of Arylsulfatase G will lead to an adverse accumulation of the protein that normally should be destroyed. With this study the research team also demonstrated that the minor faults in the ARSG gene that have been found really result in a non-functioning protein.  

The clinical picture of the type does not fit in with the already known Usher types I, II and III. Apart from a later starting age of both the loss of hearing and the retinitis pigmentosa, the ophthalmic defects are more centrally located. This means that the vision problems with these patients rather occur in the central part of the field of vision as opposed to the other Usher types, which usually show problems in the outer part of the field of vision (the periphery). As the clinical picture is consistent with all USH IV patients, researchers of the Radboud UMC are of the opinion that this is not atypical Usher, but a new clinical type: Usher Syndrome type 4.   

Hedwig: “By publishing these findings, we as researchers hope to start up a discussion in the scientific world. Various studies may together lead to the confirmation that the findings are correct or, in some cases, rebut these findings. In case of USH IV it is the accumulation of evidence in several publications that enables us to confirm that this clinical type really is a new Usher type.”    

By now, globally several patients have been diagnosed for this Usher Syndrome type and for minor faults in the same ARSG gene. Previously, these patients used to be categorised in the group ‘diagnosis unknown with atypical Usher symptoms’.    

The course of Usher Syndrome type IV
Both the loss of hearing and the complaints related to retinitis pigmentosa start at a later age with people suffering from USH IV. Patients started to develop complaints concerning hardness of hearing between the ages of 20 and 40 and the retinitis pigmentosa between the ages of 40 and 60. Based on the audiograms of USH IV patients, the research team has been able to calculate that the loss of hearing starts about the age of 17.  

The course and the progressiveness are not necessarily milder than with the other Usher types. “We still have little insight into the course of USH IV, because only fifteen patients have been described and we therefore have to base our findings on this small group.” 

Genetic tests or not?
With this discovery the researchers of the Radboudumc have managed to fit in yet another piece of the ‘Usher puzzle’.” Thanks to this, a part of the patients with an unknown diagnosis will eventually be given clarity and this is really important to this group of patients.  

Unfortunately, there still are people for whom the Usher-related symptoms cannot be confirmed by a diagnosis. This makes genetic tests so important!    

The physicians indicate that, of course, the choice is still to be made by the patient. One patient attaches a lot of value to a confirmation by means of genetic tests, while another does not.  
Hedwig: “There are various reasons to have genetic tests done or not. An advantage of a genetic diagnosis is that with this the development of a disorder can better be predicted and that this may help the patient to adapt to the situation. Imagine that you are hard of hearing at a young age and that there is a small chance of becoming visually impaired. However, if you know that you will be visually impaired, then you had better concentrate on the kind of care that will help you both early and later in life. For instance, in this case learning sign language will not be a long-term solution for your loss of hearing, but good hearing aids may make a substantial contribution.”  

Genetic tests will also help the scientific world to get further. For example, as scientific research allows for comparing the DNA of various patients, new genetic causes can be discovered. Besides, this offers a possibility for meticulously mapping out the relation between a minor fault in a gene and the corresponding complaints.
Hedwig: “Because of this, future patients can be better informed about their diagnoses. On the other hand, it is also important for any future genetic treatments to know the exact underlying deviations in the DNA.”    

Usher Syndrome: 4 types and 11 genes involved
In 2022, type IV and the ARSG gene will be added to the list of Usher types and genes involved in the development of Usher Syndrome. So at this moment, Usher Syndrome distinguishes 4 types with 11 different genes involved. [Ed.: This evidence is not entirely conclusive for USH1J (CIB2) yet]
For all these genes scientific evidence has been provided that minor faults (mutations) in these genes will result in Usher Syndrome.    

The Knowledge Portal of the Usher Syndrome Foundation provides a complete overview of the genes with the names of the ‘protein involved’.     

Here you can read the publication of the article by Hedwig Velde c.s. in Human Genetics.  

 

Moon-Rocket Grant

Usher Syndrome Foundation Grant Call:
The Moon-Rocket Grant

The use of the word ‘Ushers’ for people with Usher syndrome is meant with a wink and refers to the meaning of the English word ‘Ushers’. People with Usher syndrome are the messengers of an important story or message.

The ‘Ushers’ tell what they need, what kind of help they need, what they find important and how they experience their life with Usher syndrome.

Currently, there is no treatment available for 400.000 ‘Ushers’ in the world. What is needed for the ‘Ushers’ is more knowledge and research into the Usher Syndrome. That is why Stichting Ushersyndroom [Dutch Usher Syndrome Foundation] awards the Moon-Rocked Grant: € 100,000 for research into Usher Syndrome.

The Moon-Rocket Grant
The goal of the Moon-Rocket Grant of the Usher Syndrome Foundation is to realize our formulated moonshot: “a cure for Usher in 2025!”.

The Moon-Rocket Grant is intended to financially support research into Usher Syndrome (any form or subtype).
All research proposals submitted must fit into one of the four core values ​​the Usher Syndrome Foundation has defined by:

  • Treatment
  • Understanding
  • Diagnostics
  • Impact

The Moon-Rocket Grant will award a maximum of €100,000 per research. If there are several eligible projects, more projects can be funded. A maximum of € 200,000 is available for financing.

For more information click on the buttons below.

MOON-ROCKET GRANT FLYER GRANT CALL APPLICATION FORM

Do you have any questions or would you like to receive the application form in Word version? Mail to research@ushersyndroom.nl

1 million euro

What has Stichting Ushersyndroom [Dutch Usher syndrome Foundation] done with it?

We provide an overview and a glimpse into the future.

Mini genes USH2A
In the ‘mini genes’ project, the USH2A gene is artificially made smaller by taking specific parts of the gene and sticking these together (= minigene). This suddenly makes it possible to insert these minigenes into the current vectors for use in genetic therapy.
In this project the therapeutic effect of shortened USH2A protein variants will be tested in the zebrafish model.
The Stichting Ushersyndroom finances this study in 2016.

Read more ….

CRUSH study
The expertise centre for Usher Syndrome in Radboudumc started in 2019 a natural development study into Usher Syndrome, de CRUSH study.
This is a very important step in the research into a treatment for Usher Syndrome, because this study may substantially shorten the running time for trials. Stichting Ushersyndroom finances this five-year study.

Read more …

Mini genes USH2C

In 2019, the Usher Syndrome Foundation funded the new research into Minigenes for USH2c. USH2c is caused by mutations in the USH2c gene (ADGRV1), and these errors in the gene lead to a progressive form of hereditary deafblindness. However, this gene is very large, so researchers want to try to make an artificially shortened version of the ADGRV1 gene. These mini-genes will be small enough to fit into a ‘viral vector’, but at the same time they must also remain functional.

Read more …

Knowledge portal Usher syndrome

The Usher Syndrome knowledge portal is made available by Stichting Ushersyndroom.
A portal that has been developed for and by people with Usher syndrome in which they have bundled all their knowledge and information as experience experts and ‘Usher experts’.

Read more ….

Sleeping research
Are patients suffering from Usher Syndrome so tired because of the huge efforts made in connection with their poor hearing and eyesight or is something else going on? Researchers in the Radboudumc try to find an answers to this question. There are indications that perhaps there is more going on, a genetic cause.
In summer of 2021, the research into ‘The recognition of sleeping problems with patients with the USH2A gene’ stared. Stichting Ushersyndroom will finance a large part of this study.

Read moe ….

Database USHIII

This year in 2021, the North-American foundation Usher III Initiative has taken preliminary steps towards collecting the information necessary to establish the first comprehensive global USH3 patient database. This resource will be critical to the design of future clinical trials and will significantly advance knowledge of the disease and its impact on patients.
Stichting Ushersyndroom has committed to making a contribution to support this effort.

Read more ….

Extra large vectors on mini retinas

Stichting Ushersyndroom is funding the majority of the new research “Genetic drugs preventing blindness due to loss of USH2A function” which has recently started. The research team led by Jan Wijnholds, who works at the Leiden University Medical Center (LUMC), will test two treatment methods on ‘mini-retinas’ made from human stem cells. The researchers want to determine if the light sensitive cells in the mini-retinas can be activated by the light-sensitive cells after administration of gene therapy.

Read more ……

The dot om the horizon

The mission of the Stichting Ushersyndroom is: “In 2025, Usher Syndrome will be treatable!” This is the all-encompassing goal, the “moonshot”, from which everything else is derived. This is why Stichting Ushersyndroom is here.

  • At the beginning of 2022, Stichting Ushersyndroom will send out a call: The Moon Rocket Grant. Researchers worldwide can submit an application for a grant that contributes to the mission ofStichting Ushersyndroom: “Usher Syndrome will be treatable by 2025!”.
  • A patient brochure is in the works and will be released in early 2022. It will be available online and offline.
  • In 2022 we will start with the first webinar. This is accessible to everyone who is committed to the mission of the Stichting Ushersyndroom. A new webinar with a different speaker every quarter.
  • Of course we also want to send out a new call: Rocket Fuel Grant. And the desire to be able to subsidize even more research projects that can lead to a solution for all people with Usher syndrome.

We are well on our way to the dot on the horizon! However, a lot of money is still needed. Can we count on your support again in the coming years?

Do you have any questions or do you want to support the foundation? Send an email to info@ushersyndroom.nl

DONATE

What would you do with one million euros?

By Nico de Milliano, Chairman of the Advisory Board of Stichting Ushersyndroom [Dutch Usher syndrome Foundation]

Stichting Ushersyndroom will soon reach a wonderful milestone: the first million will be brought in even before the end of the year. And we want to celebrate this!

What is Usher Syndrome?
Usher Syndrome is a rare hereditary disorder. The children suffering from this disorder are born deaf or hard of hearing and-they will also experience a progressive loss of eyesight. Eventually, people suffering from Usher Syndrome become both deaf and blind. About 1000 people in Netherlands suffer from this syndrome.

What is Stichting Ushersyndroom?
An active group of people who are suffering from Usher Syndrome themselves or who are partner, parent or friend of someone suffering from Usher Syndrome. Stichting Ushersyndroom has existed for about six years and its mission has been formulated as: ‘A treatment for Usher Syndrome in 2025’.

In order to reach this goal, the Usher Syndrome Foundation is committed to making the syndrome more widely known, to bringing people suffering from Usher Syndrome together and to being active in fundraising.

The foundation closely works together with similar organisations abroad, such as the US, Ireland and the UK and it has good contacts with research centres all over the world.

What is money needed for?
Most of all, money is needed to finance research. As this is about a rare disorder, governments and businesses want to spend no or little money on research.

Usher Syndrome is a genetic disorder. In recent years, large steps have been taken in research that are to lead to treatment methods. The mission of the foundation is realistic, but a lot of money will be required in the coming years.

What are we going to do with one million euros?
Stichting Ushersyndroom  is really happy that we have been able to collect such a large amount of money within a few years. Thanks and honour to all those who, with large and small campaigns, have achieved this.

The money will be used for various research projects in the Netherlands and abroad. We will mention a few:

  • A study into the natural development by the Expert Centre for Usher Syndrome in Radboudumc Nijmegen, the Netherlands, will receive an amount of € 257,000 in the period 2019-2024;
  • We make a contribution of € 10,000 to setting up a database for Usher-III patients in the US;
  • We co-finance a study into sleeping problems experienced by people suffering from Usher Syndrome.

The work has not been done yet!!
Research is a long-winded matter. Therefore more money will be needed in the years to come.
Therefore, the Stichting Ushersyndroom will keep working really hard to fulfil its mission.

Let’s go for two million!

Read also:
What has Stichting Ushersyndroom done with one million euros? Here take a look at the complete overview.

New research: testing gene therapy

With extra large vectors on mini retinas 

Prof. Dr. Jan Wijnholds and promovendus Rossella Valenzano

Stichting Ushersyndroom [ Dutch Usher Syndrome Foundation] is funding the majority of the new research “Genetic drugs preventing blindness due to loss of USH2A function” which has recently started. The research team led by Jan Wijnholds, who works at the Leiden University Medical Center (LUMC), will test two treatment methods on ‘mini-retinas’ made from human stem cells. The researchers want to determine if the light sensitive cells in the mini-retinas can be activated by the light-sensitive cells after administration of gene therapy. Can the USH2a gene in the retina be replaced or is it also possible to repair the defective gene at the same time?

 

Gene therapy looks very promising and developments in this area are moving very quickly. It is a treatment method for hereditary disorders where healthy copies of genes, with errors (= mutations) have been found, in patients are replaced or repaired in the cells of an organ.

Research shows that after gene therapy, the retina can make normal connections with other cells, which can lead to a light response again. After delivering a healthy copy of the gene or repairing the gene, the retina makes the proteins it needs to see properly. With gene therapy you treat the entire gene so that it does not matter what kind of mutations you have.

Means of transport for the large USH2A gene
In gene therapy, a healthy copy of the gene is delivered to a specific location in the retina of the eye using a molecular truck, or a means of transport. This is usually done using a virus that has first been rendered harmless so that a vector remains, a kind of ‘packaging’. The most commonly used vector is the adeno-associated viral vector (AAV).
However, there is a problem. The USH2A gene is much too large for a normal AAV vector, so another alternative must be sought to deliver the large healthy copy of the USH2A gene into a patient’s eye.

Large trucks as vector
Previously, in collaboration with Dr Manuel A.F.V Gonçalves (Department of Chemical Cell Biology), the researchers in Jan Wijnholds’ lab at the LUMC, have developed new vectors into which very large genes fit, the so-called High-Capacity Adenoviral Vectors (HcAdV).
The large USH2A gene fits completely into this vector. As a result, this vector can serve as a molecular truck and can be used as a vector for gene therapy.

Mini retinas
In the research project “Genetic drugs preventing blindness due to USH2A function”, human mutant USH2A iPSC retinal organoids are used to test several new high-DNA capacity gene therapy vectors. These USH2A ‘organoids’ are ‘mini-retinas’ made from cell lines derived from USH2A patients.

These ‘mini-retinas’ are used because they allow to study the effect of loss of USH2A protein (Usherin) in the cilium of the photoreceptor. The cilium transports the essential proteins in the retina. These ‘organoids’, made from patient cell lines, could also be used in the future to test gene therapy for retinal disorders due to mutations in other Usher genes.

Replace gene and/or edit gene
In the research project of Jan Wijnholds, two types of gene therapy are being tested on the ‘mini retinas’. The first type of therapy candidate is an HcAdV vector containing a healthy copy of the USH2A gene that, after delivery, replaces the defective USH2A gene in the retina. We call this gene replacement therapy. The healthy copy of the gene must activate the gene in the photoreceptors of the ‘mini retinas’, the ‘organoids’.

The second type of therapy candidate is an HcAdV vector containing ‘a repair kit’ and, after delivery into the retina, repairs the defective USH2A gene in the eye itself. This is also known as gene editing therapy, CRISPR-Cas9 is used for this. CRISPR are pieces of DNA with codes that can detect the defective gene. The Cas9 is an enzyme that ‘cuts’ out the defective gene and ‘sticks’ a new healthy piece of DNA in it.

Both the CRISPR and Cas9 are transported in a cassette and delivered into the retina by an HcAdV vector. The USH2A gene is edited and repaired at its destination.

Promises for large groups of patients
Both technologies for genetherapeutic application are not dependent on the type of mutations in the USH2A gene. If the USH2A gene is found to be expressed in the light-sensitive cells of the mini-retinas thanks to one or both techniques, the treatment may become available to all patients with USH2A. When more money becomes available for research for these two techniques , the research team of Jan Wijnholds could also test these for other Usher genes, and could possibly also be a solution for patients with mutations in Usher genes other than USH2A.

The mission of Stichting Ushersyndroom
Annouk van Nunen, secretary of Stichting Ushersyndroom, is very pleased with the start of this research. Stichting Ushersyndroom’s mission is “In 2025, Usher Syndrome will be treatable!”.Annouk: “We want all patients to have a realistic prospect in 2025 of a treatment that can slow down, stop or even restore the further deterioration of their hearing and vision”.

The big challenge for scientists is to explore multiple research routes in order to eventually develop a treatment for all people with Usher syndrome. Stichting Ushersyndroom therefore stimulates as many lines of research as possible, so that people with Usher Syndrome can make their dreams come true. “It is fantastic that so much research is being done into Usher Syndrome in the Netherlands. This type of research is hopeful for all USH2A patients. But if it works, it could also be a solution for patients with mutations in other Usher genes, Annouk van Nunen.

This four-year study, which started in November, has been budgeted at € 250.000. Stichting Ushersyndroom is contributing € 85.000 to this research. Other funds that have contributed are: Rotterdamse Stichting Blindenbelangen, LSBS, Stichting Blindenhulp and a partial contribution from the LUMC Ophthalmology Departmen

Minigenes USH2A: General status

By Erwin van Wijk, lead researcher Radboudumc

Errors in the code of the USH2A gene explain the development of Usher syndrome in about 50% of all patients.
In addition to Usher syndrome, these errors can also lead to non-syndromic Retinitis Pigmentosa; loss of sight but without the hearing problems.
The USH2A gene contains the code for the protein usherin. After translation, the mistakes in the genetic code of USH2A also end up in the usherin protein, with the result that this protein loses its function and people lose their sight (and hearing). Giving patients a new copy of the USH2A gene that does not contain these errors could be an obvious solution. This is the principle of gene therapy.

However, for USH2A this is not as easy as it sounds.

New copies of genes are delivered with inactivated viruses, into which the genes are packaged. These viruses can be seen as small trucks. However, the loading platforms of the viruses are small. So small, in fact, that the USH2A gene simply doesn’t fit. Developing a classical gene therapy for USH2A is therefore extremely difficult from a technical point of view.

As an alternative, we have the “genetic patch” methodology, also known as exon skipping. The first patch tested is performed on patients tested in clinical trials.

Good news, but only for a limited target audience. QR-421a works for people with errors in a specific part of the USH2A gene: exon 13. This method can be extended to other USH2A genes and even to other Usher genes, but always remains only applicable for a limited number of patients.

Is there no alternative?

A few years ago we started with a new idea: can we not artificially shrink the USH2A gene, so that it fits in the loading platform of a virus and can therefore be delivered to the place where it is needed and can be used by all people with USH2A-related retinitis pigmentosa?

The main advantage is that, if effective, this method may be of value to all patients with USH2A-related retinal problems. The project “Minigenes USH2A” was born and made possible in part by a contribution from the Dutch Usher Syndrome Foundation (Stichting Ushersyndroom).

Four shortened USH2A genes were made and inserted into the retina of the USH2A zebrafish model. The shortened usherin proteins made from these minigenes in the zebrafish eye ended up in the right place in the light-sensitive cells of the retina, rods and cones. Functional tests by measuring electroretinograms (= ERG) indicate that these mini-usherin proteins are indeed (partially) functional. We have patented these results. How well they work remains to be investigated, but it is a promising starting point for further developing this method.

In the meantime, we are also looking into cultured cells to see where these mini-proteins go and whether they do not accumulate in a place where we would not want this. Fish, of course, are not people. It is therefore important to translate these results into models that are closer to humans.

We are currently trying to establish a partnership with a company that can help us take these important next steps.

Read also:

Swim at night and take a nap during the day

Zebrafishes suffering from USH2A have a disturbed sleep rhythm

Are patients suffering from Usher Syndrome so tired because of the huge efforts made in connection with their poor hearing and eyesight or is something else going on? Researchers in the Radboudumc try to find an answers to this question. There are indications that perhaps there is more going on, a genetic cause. The people of the Radboudumc have been busy trying to unravel Usher Syndrome for decades already. This summer, the research into ‘The recognition of sleeping problems with patients with the USH2A gene’ will start. Stichting Ushersyndroom (Dutch Usher Syndrome Foundation) will finance a large part of this study.

Researchers have used the zebrafish model since several years. In the laboratory of the Radboudumc both healthy zebrafishes and fishes suffering from Usher Syndrome are swimming about. Researchers noticed that the sleeping pattern shown by the fishes with a mutated USH2A gene differs from that of their healthy congeners. Actually, they sleep more often during the day and less often at night. According to Erwin, project leader of the zebrafish lab and engaged in research into Usher Syndrome for years already, the sleeping fishes are quite remarkable. It is day, there is sufficient light in the aquarium and the eyesight of the fishes is still good enough to be able to properly see light and dark. Still, they regularly fall asleep during the day.

Sleep-wake rhythm
The sleep-wake rhythm is strongly controlled by light. The retina sends signals to the pineal gland in the brains to make the sleeping hormone melatonin when the light intensity decreases. It is known that a decreasing light perception can disturb this system. However, RP patients regularly mention sleeping problems and fatigue in an early stage already, independent of the seriousness of their visual impairment.

Fatigue
Usher Syndrome is also called ‘fragmentary observation’: both hearing and seeing are done in small fragments that subsequently have to be made into a whole. This is hard work for the brain. Therefore it is not surprising that many people suffering from Usher Syndrome are tired quickly and have a higher chance of getting overstimulated and loosing energy. The energy-absorbing process of continuously compensating the one sense with the other leads to fatigue.

Sleep enables the body to recover, such as replenish energy sources, adjust muscles and other cells and reduce stress. While sleeping, we also process all we have seen, heard and done during the day. The brains are stimulated all day and have to process all this information.

Quality of sleep
The quality of sleep depends on the deep sleep, the so-called REM sleep. This makes the body recover. A good night’s rest means quickly falling asleep and sleeping all night through. In case of insufficient REM sleep, you do not feel refreshed well when you have to get up. Non-optimal REM sleep over a longer period will lead to chronic fatigue with a risk of other physical complaints.

Not tired at all
At the end of the day, when it begins to grow dark and the lights are switched off in the zebrafish lab, the last round is made in the lab. Many fishes have become less active already and are hanging around in the water without moving. They also do not react when Erwin van Wijk is walking along the aquariums.

When visiting the zebrafish lab in the evenings, he tries to make as little noise as possible and the lights are dimmed. When he switches off the lights to close the lab and leaves the lab, some groups of zebrafishes stay awake and active. The zebrafishes with mutations in the USH2A gene are not going to sleep, they are not yet tired at all.

Expression in the pineal gland
The most frequently mutated RP genes (USH2A and EYS) are both highly expressed in the pineal gland of various animal models. Researchers show that the proteins of these genes involved are not only present in large quantities in the eyes and ears, but in the pineal gland as well. This may mean that the proteins concerned also play an important role in the pineal gland and in the regulation of the day and night rhythm.

Zebrafishes with mutations in the USH2A gene show a deviating sleep-wake rhythm, while these test animals hardly show any retina degeneration.
Based on these findings researchers suspect that the sleeping problems of these groups of patients are the cause of the disorder and not just the consequence of a reduced visual function.

Comprehend
A treatment for sleep-related complaints with people who have mutations in the USH2A and EYS genes, may substantially improve their quality of life. In this project clinical and fundamental research are combined in order to comprehend these problems. The common results of these two research lines may give some tools to improve the care of patients suffering from RP and Usher Syndrome together with ophthalmologists and sleep experts.

Various research institutes are involved in this project: the Radboudumc under the leadership of Erwin van Wijk, Slaap/Waakcentrum SEIN, Hospital Gelderse Vallei, Radboud University and the Donders Institute.

This four-year study will start this summer and the costs are estimated to be € 285.000,=.  Stichting Ushersyndroom (Dutch Usher Syndrome Foundation) makes a contribution of € 125.000 with co-financing by the Dutch Dr. Vaillantfonds. Other funds that have contributed are: LSBS, ANVVB, Support Fund UitZicht (Beheer ’t Schild), the Gelderse Blindenstichting, FNWI/IWWR.

Onderzoekers en patiënten met Ushersyndroom overhandigen een cheuq ter warde van €285.000 voor het slaaponderzoek. Ze staan voor de kast met aquaria met zebravissen.

In the zebrafish lab Radboudumc. From left to right: Erik de Vrieze, Thijs Bouwman, Niels Bouwman, Ivonne Bressers. Jessie Hendricks, Devran Braam, Erwin van Wijk and Juriaan Metz.

Stichting Ushersyndroom [Dutch Usher Syndrome Foundation] Awards Grant to Usher III Initiative to Support Patient Database

A global Usher III patient (USH3) database for future clinical trials

This year, the North-American foundation Usher III Initiative has taken preliminary steps towards collecting the information necessary to establish the first comprehensive global USH3 patient database. This resource will be critical to the design of future clinical trials and will significantly advance knowledge of the disease and its impact on patients. Dr Ronald Pennings from the Radboudumc is one of several physicians and experts around the world collaborating with the Initiative in this effort. 

Cindy Elden and her father Richard, co-founders of the Usher III Initiative

Usher III Initiative
Usher III Initiative is a US based non-profit organization dedicated to developing a treatment for Usher Syndrome type 3 a rare genetic disorder characterized by progressive loss of both hearing and vision. It is estimated that over 400.000 people around the world suffer from Usher Syndrome, of which type 1 and 2 are the most common types. Only 2 percent of the patient population suffers from USH3, which is most prevalent among Finnish and Ashkenazi Jewish populations. 

Preliminary clinical trial design
The Initiative has developed BF844, a new therapeutic candidate for the treatment of USH3.
The Initiative is completing pre-clinical toxicity studies to demonstrate that BF844 can be safely administered in humans in compliance with US Food and Drug Administration (FDA) regulations. They expect that clinical trials will commence in 2022. These studies are supported by a $1M grant the Initiative recently received from the Foundation Fighting Blindness.

Consortium
Together with the Usher III Initiative and a global consortium of physicians, Dr Ronald Pennings will participate in the establishment of the USH III Patient Database. “Aggregating comprehensive genetic and  clinical data on USH3 patients is necessary to determine inclusion and eligibility criteria as well as the most effective design for clinical trials.”, commented Cindy Elden, President and Co-Founder of the Initiative and an USH3 patient.

Collaboration
Stichting Ushersyndroom [Dutch Usher Syndrome Foundation] has committed to making a $ 10,000 contribution to support this effort. This grant aligns with the mission of the Stichting Ushersyndroom, to find treatments for all types of Usher syndrome.  

“Usher Syndrome is a serious disorder, which has a deep impact on the lives of patients and their social environments.  We want to stop this disorder from the bottom of our hearts”, commented Ivonne Bressers, chairwoman and co-founder of the Stichting Ushersyndroom and USH2 patient. “We are happy to be able to participate in an international study for USH3-patients.”

Cindy Elden: “On behalf of the Usher III initiative, but also personally, I find it very inspiring to meet other people with Usher syndrome who would like to be active in the search for a treatment for all of us!”

The consortium will not be collecting any information that identifies specific patients, so the database cannot be used to recruit participants for clinical trials. Patients interested in participating in future clinical trials are encouraged to register with My Retina Tracker and the Ush Trust. Once trial investigators and sites have been identified, treating physicians may also recommend individual patients to the appropriate officials. Pursuant to global patient privacy protections, the Usher III Initiative cannot receive confidential patient data. If patients, family or friends want to connect with the Usher III Initiative for more information, they are invited to email info@usheriii.org or connect on Facebook.
Dutch patients can contact Stichting Ushersyndroom for more information on Usher syndrome and contact with fellow sufferers.
For medical advice on Usher syndrome, information on (preclinical) developments of therapeutic approaches to treat Usher syndrome or additional (genetic) diagnostics, they can reach out to the expertise center of the Radboudumc via ushersyndroom@radboudumc.nl. 

Related links:
www.usheriii.org
www.radboudumc.nl/expertisecentrum/ushersyndroom
www.ushersyndrome.nl
www.ushersyndrome.nl/knowledgeportal

Jack Weeda, draagt een bril en witte doktersjas

A view on the RUSH2a study

In the international RUSH2a study of Jacque Duncan MD, University of California, San Francisco, 120 patients spread over nine different clinics are monitored for four years. This study includes only syndromic (USH2a) and non-syndromic patients with mutations in the USH2a gene (nsRP).

The study “Rate of progression of USHer Syndrome” is done at about 20 clinical centres around the world, including the Radboudmc in Nijmegen, the Netherlands and is financed by the Foundation Fighting Blindness. Researcher Jack Weeda is working as a research optometrist in the Radboudumc on the RUSH2a study. He takes us with him in his work and gives us a view of the study.

The RUSH2a study and the CRUSH study
Recently, we already could read about the current state of affairs of the CRUSH study. Read here.
Also thanks to the Medical Advisory Council of the Stichting Ushersyndroom, the content of the CRUSH study has been aligned to RUSH2a study. This means that the research questions and the study measurements are largely similar, allowing the results of RUSH2a study to be compared with those of the CRUSH study. This comparison of the results is of scientific value.

The differences between both studies are mainly in the working area of the ENT department. For instance, the CRUSH study includes more audiological research and a one-off balance test is done. This study is conducted under the leadership of Dr Ronald Pennings. The RUSH2a study includes a one-off smelling test. The RUSH2a is conducted under the leadership of Dr Carel Hoyng. 40 patients are participating in the CRUSH study, while the RUSH2a study has about 120 international participants, nine of which are Dutch.

Here read about the similarities and the differences between the RUSH2a and the CRUSH studies.

Jack Weeda, draagt een bril en witte doktersjas

Jack Weeda, research optometrist at the Radboudumc Nijmegen, the Netherlands

Curious patients group
Jack Weeda is research optometrist at the ophthalmology department of the Radboudumc in Nijmegen. Since 2012 he has mainly worked for all scientific studies done at the department through the Trial centre of Prof Hoyng. In 2018, Jack Weeda took up the coordination of the RUSH2a study and a year later the ophthalmology part of the CRUSH study as well. In the past few years, Jack Weeda has seen about 60 Ushers and he still sees many of them on an annual basis.

 

Jack Weeda: “By now, I have got to know the patients group as a curious, positively critical, well-organised and really active patients group. I regularly see participants of the study I know appear in various ways in the media and thanks to one participant I almost even made my first appearance on television.”

The first results
The RUSH2a study started about a year before the start of the CRUSH study and by now the first results appear. For instance, an article was recently published about the ophthalmological and otological differences between people suffering from Usher Syndrome and people suffering from autosomal recessive RP (AR-RP) or non-syndromic RP (nsRP). Patients suffering from AR-RP do have mutations in the USH2a gene, but there is no or hardly any loss of hearing. The first findings have shown that patients with Usher Syndrome have more severe loss of field of vision than patients with nsRP do. Read more: https://pubmed.ncbi.nlm.nih.gov/32446738/

From the RUSH2a study an article was published about the FST study, a relatively new study that is conducted in the CRUSH and RUSH2a studies. In this FST study light flashes in three colours, being red, blue and white, are offered and of each colour it is determined which intensity of the flash is just perceived. The values resulting from this study appear to be a good indicator of the seriousness and the duration of retinitis pigmentosa. Possibly, these values can also be used to measure the effectiveness of any future therapy, but this needs further research. For the researchers it is interesting to see whether comparable results can be measured using the data from the CRUSH study. The researchers will soon start working on this. Read this article: https://pubmed.ncbi.nlm.nih.gov/33133772/

Jack Weeda hopes that together with the participating patients he will be able to make more minor and perhaps even major discoveries in both studies and in this way further solve the Usher mystery.