Revolutionizing Skin Research with Artificial Hydrogels

The human skin is the largest organ, accounting for about 15% of our body weight. It plays a vital role in protecting us from pathogens, dehydration, and temperature extremes. However, skin diseases such as skin cancer, chronic wounds, and autoimmune skin diseases are widespread, yet often poorly understood.

To address this knowledge gap, researchers at Empa have been working on developing an artificial model of human skin. This living “artificial skin” will enable scientists to simulate skin diseases, ultimately leading to a better understanding of their causes and treatment options. Unlike computer or plastic models, this innovative approach involves creating a model that contains cells and emulates the layered and wrinkled structure of human skin.

To recreate such complexity, researchers require suitable building materials. Recently, Empa scientists have made significant progress in developing hydrogels that meet these complex requirements while being easy to manufacture. The basis of their success lies in gelatin derived from the skin of cold-water fish.

Hydrogels: A Suitable Substitute for Skin Extracellular Matrix

Like most tissues, human skin consists of cells embedded in a network of proteins and other biomolecules called extracellular matrix. This matrix provides the tissue with shape and structure while sustaining the cells. However, it differs from one tissue to another – even within different layers of the skin.

Researchers have discovered that hydrogels can simulate this complex extracellular matrix. These special polymers absorb large quantities of water and other fluids, making them ideal for recreating the skin’s extracellular matrix. Moreover, many hydrogels can be processed using a 3D printer, allowing researchers to combine multiple materials and cell types into a single structure – just like real skin.

The Empa team has developed a fish gelatin-based hydrogel that can be cross-linked in just a few steps. This non-swelling hydrogel can be printed with skin cells, enabling the creation of a 3D-printed artificial skin model that closely resembles human skin.

A Promising Tool for Wound Healing

The researchers’ innovative hydrogel has far-reaching implications. Without the addition of living cells, it can be used as a dressing material. This biologically compatible material is safer and carries a lower risk of disease transmission compared to materials based on mammalian gelatin.

Moreover, the fish skin from which this hydrogel is derived is being researched as a promising tool for wound healing. The Empa team’s hydrogel is more homogeneous and can be tailored precisely to meet patient needs – with different shapes, thicknesses, and firmness levels.

The researchers have applied for a patent for their fish gelatin-based hydrogel and plan to finish developing the living skin model. This will make it available to other scientists, promoting a better understanding of skin disease development and treatment options.

Chronic rhinosinusitis, a condition characterized by inflammation of the nasal and sinus cavities, affects millions of people worldwide. Symptoms include nasal congestion, mucus secretion, and pressure in the sinuses. In severe cases, the disease can be associated with asthma or NSAID-exacerbated respiratory disease (N-ERD). The standard treatment involves nasally administered corticosteroids, which can be supplemented with orally administered corticosteroids for the polypoid form of the disease.

For patients who do not respond to medical treatments, endoscopic sinus surgery is often considered. However, a significant number of patients may require revision surgery due to persistent symptoms and disease progression. In fact, research suggests that up to 28% of patients undergoing endoscopic sinus surgery for chronic rhinosinusitis may need revision surgery within one year.

A new study published in Clinical and Translational Allergy has introduced a novel CT-scan based risk score to predict the likelihood of revision endoscopic sinus surgery. The Sinonasal Radiological Score (SR score) takes into account indicators such as non-detectable anatomy of the nasal turbinates, which is often associated with polypoid mucosal swelling, and obstructed drainage of the frontal sinus.

In comparison to the existing Lund-Mackay scoring system, the SR score provides a more accurate assessment of the risk of revision surgery. The study analyzed data from 483 patients with chronic rhinosinusitis, including those who underwent endoscopic sinus surgery within one year following their CT scan. Results showed that conditions such as asthma and N-ERD increased the risk of revision surgery.

This breakthrough research highlights the importance of early prediction of disease progression and planning for further treatment. By using the new SR score in conjunction with conventional medical and surgical treatments, clinicians can identify patients at risk of revision surgery and tailor their treatment approach accordingly.

Chewing gum is a ubiquitous part of modern life, enjoyed by millions worldwide. However, a recent pilot study has revealed that this seemingly harmless habit may have an unexpected consequence – exposure to microplastics.

Microplastics are tiny plastic particles smaller than 5 millimeters, which can be found in various everyday products like cutting boards, clothes, and even food packaging. The researchers who conducted the study wanted to examine if chewing gum could be another source of microplastic exposure.

The study involved testing five brands of synthetic gum and five brands of natural gum, all commercially available. A person chewed each piece for 4 minutes, producing saliva samples every 30 seconds. The researchers measured the number of microplastics present in each sample using a microscope or Fourier-transform infrared spectroscopy.

Interestingly, both synthetic and natural gums had similar amounts of microplastics released when chewed. In fact, some individual gum pieces released as many as 600 microplastics per gram! A typical piece of gum weighs between 2 and 6 grams, which means that a large piece could release up to 3,000 plastic particles.

The researchers estimated that if the average person chews around 160-180 small sticks of gum per year, they could ingest approximately 30,000 microplastics. This is a significant amount, considering that humans already consume tens of thousands of microplastics annually through various sources.

Most of the microplastics detached from gum within the first 2 minutes of chewing, but this didn’t happen because enzymes in saliva broke them down. Rather, the act of chewing itself was abrasive enough to make pieces flake off.

To reduce exposure to microplastics from gum, the researchers suggest that people chew one piece longer instead of popping in a new one. This way, most of the plastic particles would be released and not ingested.

The study highlights the importance of being mindful about the environment and disposing of used gum properly. If not, it’s another source of plastic pollution to the environment.

This research was funded by UCLA and the University of Hawaii Maximizing Access to Research Careers program, which is supported by the National Institutes of Health and the California Protection Council.