Brain Tissue Donation: A Crucial Way to Advance PWS Therapies

Many of us have signed the back of our driver’s license to give permission to donate our organs after we die. We generally don’t think about this kind of opportunity regarding our loved ones affected by Prader-Willi syndrome. However, tissue donation is a meaningful way to significantly advance the understanding of Prader-Willi syndrome, which some families may wish to consider.

Now there is a program that provides families an opportunity to donate the brain and tissue of a loved one who has just died, so that researchers can access a critical resource for understanding Prader-Willi syndrome. FPWR is partnering with Autism BrainNet to collect and study post-mortem brain donations. Through  this partnership, we aim to raise awareness about the importance of post-mortem brain donation, streamline the donation process for families and help them in a difficult time, and enhance the collection and distribution of high-quality tissue to researchers.

How Does Brain Tissue Donation Help?

Knowledge of Prader-Willi syndrome (PWS) is advancing, but not as quickly as the PWS community would like. One challenge is that it's more difficult to directly study disorders like PWS, which affect the brain, than disorders affecting other organs.

The development of models that mimic some aspects of PWS, including cell and animal models, have greatly advanced our understanding and have been critical for screening potential therapeutics before they're tested in patients. However there is no substitute for studying human brain tissue to unravel the complexities of the brain neurocircuitry defects in PWS.

Brain donation is critically important. Relative to donations of other organs for transplantation and/or research, brain donation is severely lagging, especially from children. “If we want better interventions, we need to look for neuropathology and find patterns of cell pathology.” says Dr. Patrick Hof, Icahn School of Medicine. "We need to build a significant research resource of donated brain tissue."

There Is No Substitute for Studying Brain Tissue

Live brain imaging techniques allow studying many aspects of the neurobiology of hyperphagia, cognition or other behaviors in individuals with PWS. Neuroimaging includes the use of various techniques to image the structure, function, or pharmacology of the nervous system. Although techniques are evolving at a fast pace allowing analyses with greater spatial and temporal resolution, they are limited for characterization of cellular structure. Study of post-mortem brain tissue gives unique information as exemplified by the work of Dr. Hof and collaborators funded by FPWR on structure of the brain in PWS.

Using brain tissue, Dr. Hof and his team are examining von Economo neurons (VENs) in the frontal lobe where executive function for decision making, sensory perception and social behavior reside. The VENs are implicated in several neuropsychiatric illnesses such as fronto-temporal dementia, schizophrenia and autism and are thought to play a role in empathy, social awareness, and self-control.Many of the phenotypic characteristics of PWS are consistent with abnormalities of the autonomic system involving functions supported by VENs. These neurons are found in higher primates, elephants and cetaceans whose survival requires social communication; they cannot be studied in mouse models of PWS. Examining whether VENs number or cellular function could be altered in PWS can only be done in post-mortem brain tissues.

The knowledge derived from quantitative neuroanatomical studies of postmortem human tissue from patients with PWS brings critical information to better understand brain function abnormalities in PWS and open new therapeutics avenues. Oxytocin therapies currently under development in PWS is a good example of that. A study published in 1995 of post-mortem brains from individuals with PWS by Swaab, et al., gave the first indication that the number of oxytocin neurons may be reduced in PWS. Complementary studies in mouse models of PWS have helped further define the nature of oxytocin deficits in PWS and are helping to guide clinical development. The therapeutic development of oxytocin in PWS also illustrates how postmortem studies are particularly useful for informing animal and cellular models, which can then be used to explore the underlying mechanisms and consequences of molecular aberrations on behavior, brain function or neurochemistry.

"Research on the human brain structure and pathology is essential," says Dr. Hof. "Even if much can be learned from models and from brain imaging studies of patients, the examination of postmortem brains is the only way to analyze disease pathology at any level of resolution and across disciplines, and this is why brain donation is so important. We have learned immensely about conditions like Alzheimer's disease and schizophrenia from brain donations. The same must be accomplished for rare diseases for which mechanisms are not always elucidated and no animal models exist."

Quality Brain Tissue is Critical for Research

Postmortem brain studies have been used to understand the relation between the brain, behavior and diseases for centuries. The sensitivity and specificity required for molecular measures are, however, greater today and rely on high tissue quality. This requires not only collecting better tissue than before, but also identifying measures of tissue quality and setting quality thresholds. Unlike animal tissue, whose condition at death can be controlled and influenced, human tissue can only be collected naturalistically.

This introduces potential confounds, based both on pre- and postmortem conditions, that may influence the quality of tissue and its ability to yield accurate results. Among the traditionally recognized confounds that can reduce tissue quality, postmortem interval, tissue collection and tissue processing are critical. Tools to assess tissue quality parameters are still evolving and stress the importance to have highly qualified expert teams to handle brain tissue collection and processing.

The Gift of Tissue Will Last Beyond a Lifetime

One of the most valuable contributions to research a person or family can make is to volunteer for a brain donation program. FPWR is partnering with Autism BrainNet to make brain donation accessible to the PWS community.

Autism BrainNet is a campaign to understand and treat a whole spectrum of pervasive developmental disorders, such as those caused by Prader-Willi syndrome. It functions as a collaborative network of academic sites that collects, stores and distributes brain tissue for research on autism spectrum disorders. It seeks to support the highest-quality and most rigorous research into the underlying genetic and neuropathological mechanisms that contribute to autism and related neurodevelopmental disorders such as PWS.

The network is funded by the Simons Foundation and is directed by Professor David Amaral, a distinguished neuroanatomist and research director of the MIND institute at the University of California, Davis. Autism BrainNet has established several partnerships with non-profit organizations to develop a unified approach for brain banking for autism and related neurodevelopmental disorders. These include partnering with the NIH NeuroBioBank, the Dup15q Alliance, the Phelan-McDermind Syndrome Foundation and more recently FPWR. Autism BrainNet has received over 100 donations since it began collecting tissue in June 2014.

Tissue collection and storage is carried out at four regional nodes across the United States: Sacramento (University of California, Davis), Dallas (University of Texas Southwestern Medical Center), Boston (Harvard Beth Israel Hospital) and New York City (Icahn School of Medicine at Mount Sinai directed by Dr. Hof) and an international node in the United Kingdom (the Oxford Brain Bank at Oxford University). Tissue distribution is overseen by a scientific review committee that comprises members of the FPWR research team who will review request for PWS brain tissue to ensure that brain tissue applications are scientifically meritorious and relevant to PWS.

How PWS Brain Tissue Donation Works

Brain tissue recovery is coordinated nationally by Autism BrainNet. A 24-hour hotline number is available for families for further information on the donation process or for brain donation (see below).

When brain tissue donation occurs, a pathologist performs the procedure and coordinates with the funeral director. Your loved one is treated with the utmost respect and dignity. The procedures used to obtain brain tissue will not affect any funeral arrangements, including viewing, that you wish to make.

The Autism BrainNet assumes all costs related to obtaining tissue.

The team at Autism BrainNet will also follow up after the donation occurs to schedule a visit with the donor’s family. The purpose of this visit is to collect essential documentation about the donor and to learn more about their background.

Registration

Registering to donate brain tissue does not mean that anyone anticipates your child will die an early death. It does mean, however, that you are prepared to act if such an unexpected and tragic event were to occur. 

• You can register for brain tissue donation at https://www.autismbrainnet.org/newsletter/

As a registrant, you'll receive a quarterly newsletter on discoveries that have been significantly impacted by brain tissue donation.

The death of a loved one is an incredibly difficult time, and for that reason it can be helpful to consider, discuss, and register for brain tissue donation in advance. However, donation can still be arranged even if families have not pre-registered. 

If You Aren't Registered, You Can Still Donate

• Even if you aren't registered, you can still arrange for donation by calling 1-877-333-0999. This is a 24-hour toll-free hotline.

All inquiries are treated with absolute confidentiality. You'll be connected with the Autism BrainNet coordinator, who will answer questions you might have about donation. Should you choose to proceed with donation, you will be put in touch directly with the local site who will make the appropriate arrangements. 

Organ donation is a highly personal decision that has the power to accelerate research and transform the lives of countless families affected by PWS. It reflects a family’s choice to benefit others, and honors the complex and challenging life of the affected child. You can make a tremendous difference in research into Prader-Willi syndrome by participating in this program.

For questions regarding the brain tissue donation process, please call Autism BrainNet at 877-333-0999 or visit the Autism Brain Net website.