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The Creation of Successful Scaffolds for Tissue Engineering


The Creation of Successful Scaffolds for Tissue Engineering


Tissue engineering is a broad field with applications ranging from pharmaceutical testing to total organ replacement. Recently, there has been extensive research on creating tissue that is able to replace or repair natural human tissue. Much of this research focuses on the creation of scaffolds that can both support cell growth and successfully integrate with the surrounding tissue. This article will introduce the concept of a scaffold for tissue engineering; discuss key areas of research including biomolecule use, vascularization, mechanical strength, and tissue attachment; and introduce some important recent advancements in these areas.


Tissue engineering relies on four main factors: the growth of appropriate cells, the introduction of the proper biomolecules to these cells, the attachment of the cells to an appropriate scaffold, and the application of specific mechanical and biological forces to develop the completed tissue.1

Successful cell culture has been possible since the 1960’s, but these early methods lacked the adaptability necessary to make functioning tissues. With the introduction of induced pluripotent stem cells in 2008, however, researchers have not faced the same resource limitation previously encountered. As a result, the growth of cells of a desired type has not been limiting to researchers in tissue engineering and thus warrants less concern than other factors in contemporary tissue engineering.2,3

Similarly, the introduction of essential biomolecules (such as growth factors) to the developing tissue has generally not restricted modern tissue engineering efforts. Extensive research and knowledge of biomolecule function as well as relatively reliable methods of obtaining important biomolecules have allowed researchers to make engineered tissues more successfully emulate functional human tissue using biomolecules.4,5 Despite these advancements in information and procurement methods, however, the ability of biomolecules to improve engineered tissue often relies on the structure and chemical composition of the scaffold material.6

Cellular attachment has also been a heavily explored field of research. This refers specifically to the ability of the engineered tissue to seamlessly integrate into the surrounding tissue. Studies in cellular attachment often focus on qualities of scaffolds such as porosity as well as the introduction of biomolecules to encourage tissue union on the cellular level. Like biomolecule effectiveness, successful cellular attachment depends on the material and structure of the tissue scaffolding.7

Also critical to developing functional tissue is exposing it to the right environment. This development of tissue properties via the application of mechanical and biological forces depends strongly on finding materials that can withstand the required forces while supplying cells with the necessary environment and nutrients. Previous research in this has focused on several scaffold materials for various reasons. However, improvements to the material or the specific methods of development are still greatly needed in order to create functional implantable tissue. Because of the difficulty of conducting research in this area, devoted efforts to improving these methods remain critical to successful tissue engineering.

In order for a scaffold to be capable of supporting cells until the formation of a functioning tissue, it is necessary to satisfy several key requirements, principally introduction of helpful biomolecules, vascularization, mechanical function, appropriate chemical and physical environment, and compatibility with surrounding biological tissue.8,9 Great progress has been made towards satisfying many of these conditions, but further research in the field of tissue engineering must address challenges with existing scaffolds and improve their utility for replacing or repairing human tissue.

Key Research Areas of Scaffolding Design


Throughout most early tissue engineering projects, researchers focused on simple cell culture surrounding specific material scaffolds.10 Promising developments such as the creation of engineered cartilage motivated further funding and interest in research. However, these early efforts missed out on several crucial factors to tissue engineering that allow implantable tissue to take on more complex functional roles. In order to create tissue that is functional and able to direct biological processes alongside nearby natural tissue, it is important to understand the interactions of biomolecules with engineered tissue.

Because the ultimate goal of tissue engineering is to create functional, implantable tissue that mimics biological systems, most important biomolecules have been explored by researchers in the medical field outside of tissue engineering. As a result, a solid body of research exists describing the functions and interactions of various biomolecules. Because of this existing information, understanding their potential uses in tissue engineering relies mainly on studying the interactions of biomolecules with materials which are not native to the body; most commonly, these non-biological materials are used as scaffolding. To complicate the topic further, biomolecules are a considerably large category encompassing everything from DNA to glucose to proteins. As such, it is most necessary to focus on those that interact closely with engineered tissue.

One type of biomolecule that is subject to much research and speculation in current tissue engineering is the growth factor.11 Specific growth factors can have a variety of functions from general cell proliferation to the formation of blood cells and vessels.12-14 They can also be responsible for disease, especially the unchecked cell generation of cancer.15 Many of the positive roles have direct applications to tissue engineering. For example, Transforming Growth Factor-beta (TGF-β) regulates normal growth and development in humans.16 One study found that while addition of ligands to engineered tissue could increase cellular adhesion to nearby cells, the addition also decreased the generation of the extracellular matrix, a key structure in functional tissue.17 To remedy this, the researchers then tested the same method with the addition of TGF-β. They saw a significant increase in the generation of the extracellular matrix, improving their engineered tissue’s ability to become functional faster and more effectively. Clearly, a combination of growth factors and other tissue engineering methods can lead to better outcomes for functional tissue engineering.

With the utility of growth factors established, delivery methods become very important. Several methods have been shown as effective, including delivery in a gelatin carrier.18 However, some of the most promising procedures rely on the scaffolding’s properties. One set of studies mimicked the natural release of growth factors through the extracellular matrix by creating a nanofiber scaffold containing growth factors for delayed release.19 The study saw an positive influence on the behavior of cells as a result of the release of growth factor. Other methods vary physical properties of the scaffold such as pore size to trigger immune pathways that release regenerative growth factors, as will be discussed later. The use of biomolecules and specifically growth factors is heavily linked to the choice of scaffolding material and can be critical to the success of an engineered tissue.


Because almost all tissue cannot survive without proper oxygenation, engineered tissue vascularization has been a focus of many researchers in recent years to optimize chances of engineered tissue success.20 For many of the areas of advancement, this process depends on the scaffold.21 The actual requirements for level and complexity of vasculature vary greatly based on the type of tissue; the requirements for blood flow in the highly vascularized lungs are different than those for cortical bone.22,23 Therefore, it is more appropriate for this topic to address the methods which have been developed for creating vascularized tissue rather than the actual designs of specific tissues.

One method that has shown great promise is the use of modified 3D printers to cast vascularized tissue.24 This method uses the relatively new printing technology to create carbohydrate glass networks in the form of the desired vascular network. The network is then coated with a hydrogel scaffold to allow cells to grow. The carbohydrate glass is then dissolved from inside of the hydrogel, leaving an open vasculature in a specific shape. This method has been successful in achieving cell growth in areas of engineered tissue that would normally undergo necrosis. Even more remarkably, the created vasculature showed the ability to branch into a more complex system when coated with endothelial cells.24

However, this method is not always applicable. Many tissue types require scaffolds that are more rigid or have different properties than hydrogels. In this case, researchers have focused on the effect of a material’s porosity on angiogenesis.7,25 Several key factors have been identified for blood vessel growth, including pore size, surface area, and endothelial cell seeding similar to that which was successful in 3D printed hydrogels. Of course, many other methods are currently being researched based on a variety of scaffolds. Improvements on these methods, combined with better research into the interactions of vascularization with biomaterial attachment, show great promise for engineering complex, differentiated tissue.

Mechanical Strength

Research has consistently demonstrated that large-scale cell culture is not limiting to bioengineering. With the introduction of technology like bioreactors or three-dimensional cell culture plates, growing cells of the desired qualities and in the appropriate form continues to become easier for researchers; this in turn allows for a focus on factors beyond simply gathering the proper types of cells.2 This is important because most applications in tissue engineering require more than just the ability to create groupings of cells—the cells must have a certain degree of mechanical strength in order to functionally replace tissue that experiences physical pressure.

The mechanical strength of a tissue is a result of many developmental factors and can be classified in different ways, often based on the type of force applied to the tissue or the amount of force the tissue is able to withstand. Regardless, mechanical strength of a tissue primarily relies on the physical strength of the tissue and its ability for its cells to function under an applied pressure; these are both products of the material and fabrication methods of the scaffolding used. For example, scaffolds in bone tissue engineering are often measured for compressive strength. Studies have found that certain techniques, such as cooking in a vacuum oven, may increase compressive strength.26 One group found that they were able to match the higher end of the possible strength of cancellous (spongy) bone via 3D printing by using specific molecules within the binding layers.27 This simple change resulted in scaffolding that displayed ten times the mechanical strength of scaffolding with traditional materials, a value within the range for natural bone. Additionally, the use of specific binding agents between layers of scaffold resulted in increased cellular attachment, the implications of which will be discussed later.27 These changes result in tissue that is more able to meet the functional requirements and therefore to be easily used as a replacement for bone. Thus, simple changes in materials and methods used can drastically increase the mechanical usability of scaffolds and often have positive effects on other important qualities for certain types of tissue.

Clearly, not all designed tissues require the mechanical strength of bone; contrastingly for contrast, the brain experiences less than one kPa of pressure compared to the for bone’s 106 kPa pressure bones experience.28 Thus, not all scaffolds must support the same amount of pressure, and scaffolds must be made accordingly to accommodate for these structural differences. Additionally, other tissues might experience forces such as tension or torsion based on their locations within the body. This means that mechanical properties must be looked at on a tissue-by-tissue basis in order to determine their corresponding scaffolding structures. But mechanical limitations are only a primary factor in bone, cartilage, and cardiovascular engineered tissue, the latter of which has significantly more complicated mechanical requirements.29

Research in the past few years has investigated increasingly complex aspects of scaffold design and their effects on macroscopic physical properties. For example, it is generally accepted that pore size and related surface area within engineered bone replacements are key to cellular attachment. However, recent advances in scaffold fabrication techniques have allowed researchers to investigate very specific properties of these pores such as their individual geometry. In one recent study, it was found that using an inverse opal geometry--an architecture known for its high strength in materials engineering--for pores led to a doubling of mineralization within a bone engineering scaffold.30 Mineralization is a crucial quality of bone because of its contribution to compressive strength.31 This result is so important because it demonstrates the recent ability of researchers to alter scaffolds on a microscopic level in order to affect macroscopic changes in tissue properties.

Attachment to Nearby Tissue

Even with an ideal design, a tissue’s success as an implant relies on its ability to integrate with the surrounding tissue. For some types of tissue, this is simply a matter of avoiding rejection by the host through an immune response.32 In these cases, it is important to choose materials with a specific consideration for reducing this immune response. Over the past several decades, it has been shown that the key requirement for biocompatibility is the use of materials that are nearly biologically inert and thus do not trigger a negative response from natural tissue.33 This is based on the strategy which focuses on minimizing the immune response of tissue surrounding the implant in order to avoid issues such as inflammation which might be detrimental to the patient undergoing the procedure. This method has been relatively effective for implants ranging from total joint replacements to heart valves.

Avoiding a negative immune response has proven successful for some medical fields. However, more complex solutions involving a guided immune response might be necessary for engineered tissue implants to survive and take on the intended function. This issue of balancing biochemical inertness and tissue survival has led researchers to investigate the possibility of using the host immune response in an advantageous way for the success of the implant.34 This method of intentionally triggering surrounding natural tissue relies on the understanding that immune response is actually essential to tissue repair. While an inert biomaterial may be able to avoid a negative reaction, it will also discourage a positive reaction. Without provoking some sort of response to the new tissue, an implant will remain foreign to bordering tissue; this means that the cells cannot take on important functions, limiting the success of any biomaterial that has more than a mechanical use.

Current studies have focused primarily on modifying surface topography and chemistry to target a positive immune reaction in the cells surrounding the new tissue. One example is the grafting of oligopeptides onto the surface of an implant to stimulate macrophage response. This method ultimately leads to the release of growth factors and greater levels of cellular attachment because of the chemical signals involved in the natural immune response.35 Another study found that the use of a certain pore size in the scaffold material led to faster and more complete healing in an in vivo study using rabbits. Upon further investigation, it was found that the smaller pore size was interacting with macrophages involved in the triggered immune response; this interaction ultimately led more macrophages to differentiate into a regenerative pathway, leading to better and faster healing of the implant with the surrounding tissue.36 Similar studies have investigated the effect of methods such as attaching surface proteins with similarly enlightening results. These and other promising studies have led to an increased awareness of chemical signaling as a method to enhance biomaterial integration with larger implications including faster healing time and greater functionality.


The use of scaffolds for tissue engineering has been the subject of much research because of its potential for extensive utilization in the medical field. Recent advancements have focused on several areas, particularly the use of biomolecules, improved vascularization, increases in mechanical strength, and attachment to existing tissue. Advancements in each of these fields have been closely related to the use of scaffolding. Several biomolecules, especially growth factors, have led to a greater ability for tissue to adapt as an integrated part of the body after implantation. These growth factors rely on efficient means of delivery, notably through inclusion in the scaffold, in order to have an effect on the tissue. The development of new methods and refinement of existing ones has allowed researchers to successfully vascularize tissue on multiple types of scaffolds. Likewise, better methods of strengthening engineered tissue scaffolds before cell growth and implantation have allowed for improved functionality, especially under mechanical forces. Modifications to scaffolding and the addition of special molecules have allowed for increased cellular attachment, improving the efficacy of engineered tissue for implantation. Further advancement in each of these areas could lead to more effective scaffolds and the ability to successfully use engineered tissue for functional implants in medical treatments.


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  17. Mann, Brenda K, Rachael H Schmedlen, and Jennifer L West. “Tethered-TGF-β Increases Extracellular Matrix Production of Vascular Smooth Muscle Cells.” Biomaterials 22.5 (2001): 439–444. Web.
  18. Malafaya, Patrícia B., Gabriela A. Silva, and Rui L. Reis. “Natural–origin Polymers as Carriers and Scaffolds for Biomolecules and Cell Delivery in Tissue Engineering Applications.” Matrices and Scaffolds for Drug Delivery in Tissue Engineering 59.4–5 (2007): 207–233. Web.
  19. Sahoo, Sambit et al. “Growth Factor Delivery through Electrospun Nanofibers in Scaffolds for Tissue Engineering Applications.” Journal of Biomedical Materials Research Part A 93A.4 (2010): 1539–1550. Web.
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  21. Drury, Jeanie L., and David J. Mooney. “Hydrogels for Tissue Engineering: Scaffold Design Variables and Applications.” Synthesis of Biomimetic Polymers 24.24 (2003): 4337–4351. Web.
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Molecular Mechanisms Behind Alzheimer’s Disease and Epilepsy


Molecular Mechanisms Behind Alzheimer’s Disease and Epilepsy


Seizures are characterized by periods of high neuronal activity and are caused by alterations in synaptic function that disrupt the equilibrium between excitation and inhibition in neurons. While often associated with epilepsy, seizures can also occur after brain injuries and interestingly, are common in Alzheimer’s patients. While Alzheimer’s patients rarely show the common physical signs of seizures, recent research has shown that electroencephalogram (EEG) technology can detect nonconvulsive seizures in Alzheimer’s patients. Furthermore, patients with Alzheimer’s have a 6- to 10-fold increase in the probability of developing seizures during the course of their disease compared to healthy controls.2 While previous research has focused on the underlying molecular mechanisms of Aβ tangles in the brain, the research presented here relates seizures to the cognitive decline in Alzheimer’s patients in an attempt to find therapeutic approaches that tackle both epilepsy and Alzheimer’s.


The hippocampus is found in the temporal lobe and is involved in the creation and consolidation of new memories. It is the first part of the brain to undergo neurodegeneration in Alzheimer’s disease, and as such, the disease is characterized by memory loss. Alzheimer’s is different than other types of dementia because patients’ episodic memories are affected strongly and quickly. Likewise, patients who suffer from epilepsy also exhibit neurodegeneration in their hippocampi and have impaired episodic memories. Such similarities led researchers to hypothesize that the two diseases have the same pathophysiological mechanisms. In one study, four epileptic patients exhibited progressive memory loss that clinically resembled Alzheimer’s disease.6 In another study, researchers found that seizures precede cognitive symptoms in late-onset Alzheimer’s disease.7 This led researchers to hypothesize that a high incidence of seizures increases the rate of cognitive decline in Alzheimer’s patients. However, much is yet to be discovered about the molecular mechanisms underlying seizure activity and cognitive impairments.

Amyloid precursor protein (APP) is the precursor molecule to Aβ, the polypeptide that makes up the Aβ plaques found in the brains of Alzheimer’s patients. In many Alzheimer’s labs, the J20 APP mouse model of disease is used to simulate human Alzheimer’s. These mice overexpress the human form of APP, develop amyloid plaques, and have severe deficits in learning and memory. The mice also have high levels of epileptiform activity and exhibit spontaneous seizures that are characteristic of epilepsy.11 Understanding the long-lasting effects of these seizures is important in designing therapies for a disease that is affected by recurrent seizures. Thus, comparing the APP mouse model of disease with the temporal lobe epilepsy (TLE) mouse model is essential in unraveling the mysteries of seizures and cognitive decline.

Shared Pathology of the Two Diseases

The molecular mechanisms behind the two diseases are still unknown and under much research. An early observation in both TLE and Alzheimer’s involved a decrease in calbindin-28DK, a calcium buffering protein, in the hippocampus.10 Neuronal calcium buffering and calcium homeostasis are well-known to be involved in learning and memory. Calcium channels are involved in synaptic transmission, and a high calcium ion influx often results in altered neuronal excitability and calcium signaling. Calbindin acts as a buffer for binding free Ca2+ and is thus critical to calcium homeostasis.

Some APP mice have severe seizures and an extremely high loss of calbindin, while other APP mice exhibit no loss in calbindin. The reasons behind this is unclear, but like patients, mice are also very variable.

The loss of calbindin in both Alzheimer’s and TLE is highly correlated with cognitive deficits. However, the molecular mechanism behind the calbindin loss is unclear. Many researchers are now working to uncover this mechanism in the hopes of preventing the calbindin loss, thereby improving therapeutic avenues for Alzheimer’s and epilepsy patients.

Seizures and Neurogenesis

The dentate gyrus is one of the two areas of the adult brain that exhibit neurogenesis.13 Understanding neurogenesis in the hippocampus can lead to promising therapeutic targets in the form of neuronal replacement therapy. Preliminary research in Alzheimer’s and TLE has shown changes in neurogenesis over the course of the disease.14 However, whether neurogenesis is increased or decreased remains a controversial topic, as studies frequently contradict each other.

Many researchers study neurogenesis in the context of different diseases. In memory research, neurogenesis is thought to be involved in both memory formation and memory consolidation.12 Alzheimer’s leads to the gradual decrease in the generation of neural progenitors, the stem cells that can differentiate to create a variety of different neuronal and glial cell types.8 Further studies have shown that the neural stem cell pool undergoes accelerated depletion due to seizure activity.15 Initially, heightened neuronal activity stimulates neural progenitors to divide rapidly at a much faster rate than controls. This rapid division depletes the limited stem cell pool prematurely. Interestingly enough, this enhanced neurogenesis is detected long before other AD-linked pathologies. When the APP mice become older, the stem cell pool is depleted to a point where neurogenesis occurs much slower compared to controls.9 This is thought to represent memory deficits, in that the APP mice can no longer consolidate new memories as effectively. The same phenomenon occurs in mice with TLE.

The discovery of this premature neurogenesis in Alzheimer’s disease has many therapeutic benefits. For one, enhanced neurogenesis can be used as a marker for Alzheimer’s long before any symptoms are present. Furthermore, targeting increased neurogenesis holds potential as a therapeutic avenue, leading to better remedies for preventing the pathological effects of recurrent seizures in Alzheimer’s disease.


Research linking epilepsy with other neurodegenerative disorders is still in its infancy, and leaves many researchers skeptical about the potential to create a single therapy for multiple conditions. Previous EEG studies recorded Alzheimer’s patients for a few hours at a time and found limited epileptiform activity; enhanced overnight technology has shown that about half of Alzheimer’s patients have epileptiform activity in a 24-hour period, with most activity occurring during sleep1. Recording patients for even longer periods of time will likely raise this percentage. Further research is being conducted to show the importance of seizures in enhancing cognitive deficits and understanding Alzheimer’s disease, and could lead to amazing therapeutic advances in the future.


  1. Vossel, K. A. et. al. Incidence and Impact of Subclinical Epileptiform Activity. Ann Neurol. 2016.
  2. Pandis, D. Scarmeas, N. Seizures in Alzheimer Disease: Clinical and Epidemiological Data. Epilepsy Curr. 2012. 12(5), 184-187.
  3. Chin, J. Scharfman, H. Shared cognitive and behavioral impairments in epilepsy and Alzheimer’s disease and potential underlying mechanisms. Epilepsy & Behavior. 2013. 26, 343-351.
  4. Carter, D. S. et. al. Long-term decrease in calbindin-D28K expression in the hippocampus of epileptic rats following pilocarpine-induced status epilepticus. Epilepsy Res. 2008. 79(2-3), 213-223.
  5. Jin, K. et. al. Increased hippocampal neurogenesis in Alzheimer’s Disease. Proc Natl Acad Sci. 2004. 101(1), 343-347.
  6. Ito, M., Echizenya, N., Nemoto, D., & Kase, M. (2009). A case series of epilepsy-derived memory impairment resembling Alzheimer disease. Alzheimer Disease and Associated Disorders, 23(4), 406–409.
  7. Picco, A., Archetti, S., Ferrara, M., Arnaldi, D., Piccini, A., Serrati, C., … Nobili, F. (2011). Seizures can precede cognitive symptoms in late-onset Alzheimer’s disease. Journal of Alzheimer’s Disease: JAD, 27(4), 737–742.
  8. Zeng, Q., Zheng, M., Zhang, T., & He, G. (2016). Hippocampal neurogenesis in the APP/PS1/nestin-GFP triple transgenic mouse model of Alzheimer’s disease. Neuroscience, 314, 64–74.
  9. Lopez-Toledano, M. A., Ali Faghihi, M., Patel, N. S., & Wahlestedt, C. (2010). Adult neurogenesis: a potential tool for early diagnosis in Alzheimer’s disease? Journal of Alzheimer’s Disease: JAD, 20(2), 395–408.
  10. Palop, J. J., Jones, B., Kekonius, L., Chin, J., Yu, G.-Q., Raber, J., … Mucke, L. (2003). Neuronal depletion of calcium-dependent proteins in the dentate gyrus istightly linked to Alzheimer’s disease-related cognitive deficits. Proceedings of the National Academy of Sciences of the United States of America, 100(16), 9572–9577.
  11. Research Models: J20. AlzForum: Networking for a Cure.
  12. Kitamura, T. Inokuchi, K. (2014). Role of adult neurogenesis in hippocampal-cortical memory consolidation. Molecular Brain 7:13. 10.1186/1756-6606-7-13.
  13. Piatti, V. Ewell, L. Leutgeb, J. Neurogenesis in the dentate gyrus: carrying the message or dictating the tone. Frontiers in Neuroscience 7:50. doi: 10.3389/fnins.2013.00050
  14. Noebels, J. (2011). A Perfect Storm: Converging Paths of Epilepsy and Alzheimer’s Dementia Intersect in the Hippocampal Formation. Epilepsia 52, 39-46. doi:  10.1111/j.1528-1167.2010.02909.x
  15. Jasper, H.; In Jasper’s Basic Mechanisms of the Epilepsies, 4; Rogawski, M., et al., Eds.; Oxford University Press: USA, 2012


The Fight Against Neurodegeneration


The Fight Against Neurodegeneration

“You know that it will be a big change, but you really don’t have a clue about your future.”A 34-year-old postdoctoral researcher at the Telethon Institute of Genetics and Medicine in Italy at the time, Dr. Sardiello had made a discovery that would change his life forever. Eight years later, Dr. Sardiello is now the principal investigator of a lab in the Jan and Dan Duncan Neurological Research Institute (NRI) where he continues the work that had brought him and his lab to America.

Throughout his undergraduate career, Sardiello knew he wanted to be involved in some manner with biology and genetics research, but his passion was truly revealed in 2000: the year he began his doctoral studies. It was during this year that the full DNA sequence of the common fruit fly was released, which constituted the first ever complete genome of a complex organism. At the time, Sardiello was working in a lab that used fruit flies as a model, and this discovery served to spur his interest in genetics. As the golden age of genetics began, so did Sardiello’s love for the subject, leading to his completion of a PhD in Genetic and Molecular Evolution at the Telethon Institute of Genetics and Medicine. It was at this institute that his team made the discovery that would bring him to America: the function of Transcription Factor EB, colloquially known as TFEB.

Many knew of the existence of TFEB, but no one knew of its function. Dr. Sardiello and his team changed that. In 2009, they discovered that the gene is the master regulator for lysosomal biogenesis and function. In other words, TFEB works as a genetic switch that turns on the production of new lysosomes, an exciting discovery.1 Before the discovery of TFEB’s function, lysosomes were commonly known as the incinerator or the garbage can of the cell, as these organelles were thought to be essentially specialized containers that get rid of cellular waste. However, with the discovery of TFEB’s function, we now know that lysosomes have a much more active role in catabolic pathways and the maintenance of cell homeostasis. Sardiello’s groundbreaking findings were published in Science, one of the most prestigious peer reviewed journals in the scientific world. Speaking about his success, Sardiello said, “The bottom line was that there was some sort of feeling that a big change was about to come, but we didn’t have a clue what. There was just no possible measure at the time.”

Riding the success of his paper, Sardiello moved to the United States and established his own lab with the purpose of defeating the family of diseases known as Neuronal Ceroid Lipofuscinosis (NCLs). NCLs are genetic diseases caused by the malfunction of lysosomes. This malfunction causes waste to accumulate in the cell and eventually block cell function, leading to cell death. While NCLs cause cell death throughout the body, certain specialized cells such as neurons do not regenerate. Therefore, NCLs are generally neurodegenerative diseases. While there are many variants of NCLs, they all result in premature death after loss of neural functions such as sight, motor ability, and memory.

“With current technology,” Sardiello said, “the disease is incurable, since it is genetic. In order to cure a genetic disease, you have to somehow bring the correct gene into every single cell of the body.” With our current understanding of biology, this is impossible. Instead, doctors can work to treat the disease, and halt the progress of the symptoms. Essentially, his lab has found a way using TFEB to enhance the function of the lysosomes in order to fight the progress of the NCL diseases.

In addition to genetic enhancement, Sardiello is also focusing on finding drugs that will activate TFEB and thereby increase lysosomal function. To test these new methods, the Sardiello lab uses mouse models that encapsulate most of the symptoms in NCL patients. “Our current results indicate that drug therapy for NCLs is viable, and we are working to incorporate these strategies into clinical therapy,” Sardiello said. So far the lab has identified three different drugs or drug combinations that may be viable for treatment of this incurable disease.

While it might be easy to talk about NCLs and other diseases in terms of their definitions and effects, it is important to realize that behind every disease are real people and real patients. The goal of the Sardiello Lab is not just to do science and advance humanity, but also to help patients and give them hope. One such patient is a boy named Will Herndon. Will was diagnosed with NCL type 3, and his story is one of resilience, strength, and hope.

When Will was diagnosed with Batten Disease at the age of six, the doctors informed him and his family that there was little they could do. At the time, there was little to no viable research done in the field. However, despite being faced with terminal illness, Will and his parents never lost sight of what was most important: hope. While others might have given up, Missy and Wayne Herndon instead founded The Will Herndon Research Fund - also known as HOPE - in 2009, playing a large role in bringing Dr. Sardiello and his lab to the United States. Yearly, the foundation holds a fundraiser to raise awareness and money that goes towards defeating the NCL diseases. Upon its inception, the fundraiser had only a couple of hundred attendees- now, only half a decade later, thousands of like-minded people arrive each year to support Will and others with the same disease. “Failure is not an option,” Missy Herndon said forcefully during the 2016 banquet. “Not for Will, and not for any other child with Batten disease.” It was clear from the strength of her words that she believed in the science, and that she believed in the research.

“I have a newborn son,” Sardiello said, recalling the speech. “I can’t imagine going through what Missy and Wayne had to. I felt involved and I felt empathy, but most of all, I felt respect for Will’s parents. They are truly exceptional people and go far and beyond what anyone can expect of them. In face of adversity, they are tireless, they won’t stop, and their commitment is amazing.”

When one hears about science and labs, it usually brings to mind arrays of test tubes and flasks or the futuristic possibilities of science. In all of this, one tends to forget about the people behind the test bench: the scientists that conduct the experiments and uncover the next step in the collective knowledge of humanity, people like Dr. Sardiello. However, Sardiello isn’t alone in his endeavors, as he is supported by the members of his lab.

Each and every one of the researchers in Marco’s lab is an international citizen, hailing from at least four different countries in order to work towards a common cause: Parisa Lombardi from Iran, Lakshya Bajaj, Jaiprakash Sharma, and Pal Rituraj from India, Abdallah Amawi, from Jordan, and of course, Marco Sardiello and Alberto di Ronza, from Italy. Despite the vast distances in both geography and culture, the chemistry among the team was palpable, and while how they got to America varied, the conviction that they had a responsibility to help other people and defeat disease was always the same.

Humans have always been predisposed to move forwards. It is because of this propensity that humans have been able to eradicate disease and change the environments that surround us. However, behind all of our achievements lies scientific advancement, and behind it are the people that we so often forget. Science shouldn’t be detached from the humans working to advance it, but rather integrated with the men and women working to make the world a better place. Dr. Sardiello and his lab represent the constant innovation and curiosity of the research community, ideals that are validated in the courage of Will Herndon and his family. In many ways, the Sardiello lab embodies what science truly represents: humans working for something far greater than themselves.


  1. Sardiello, M.; Palmieri, M.; di Ronza, A.; Medina, D.L.; Valenza, M.; Alessandro, V. Science. 2009, 325, 473-477.