The skin is one of the first places where the body meets the outside world. Heat, air pollution and other environmental factors can influence inflammatory processes and the immune system. But measuring what happens in the skin is not always easy. Current methods, such as biopsies, tape stripping or suction blister fluid, can cause discomfort and are not ideal for repeated monitoring.

Within the Flagship Personalized, Real-Time Health Impact of Climate Change and Pollution, researchers are developing technologies to make biological responses to environmental stress more measurable. One of these innovations is the skin wash device: a non-invasive method to collect inflammatory biomarkers directly from the skin.

From visible symptoms to measurable biomarkers

For skin diseases such as atopic dermatitis and psoriasis, diagnosis and monitoring are still largely based on clinical assessment: what the skin looks like, where lesions appear, and how severe symptoms are. This remains essential, but it does not always show what is happening immunologically beneath the surface.

The skin wash device offers an additional route. Developed by Erasmus MC researchers, it works like a small, skin-friendly sampling chamber: the device is placed on the skin with a wash fluid that collects cytokines, chemokines and other immune mediators released at the skin surface. These proteins are then measured in the lab, allowing researchers to capture inflammatory signals from the skin without damaging it.

In first studies with healthy volunteers and patients with atopic dermatitis or psoriasis, the team detected elevated inflammatory markers in patients and was able to distinguish between patient groups based on cytokine profiles without damaging the skin.

Technical note The skin wash device consists of a small custom-made 3D-printed sampling well (a), covered by a nylon membrane (b) and secured with an O-ring (c). The well is attached to the skin using an adjustable bracelet (d) and closed with a screw cap (e). This creates a small skin-friendly sampling chamber in which wash fluid can collect immune mediators released at the skin surface, while the membrane helps prevent the collection materials from coming into direct contact with the skin.

Towards use in patients and real-life settings

The first clinical pilot studies have been completed and the method has been published in JID Innovations. The team is now exploring how the technology can be further validated in concrete clinical use cases, including immune-mediated diseases such as systemic sclerosis.

In parallel, the researchers are exploring how the device could be developed further towards future use in research and care. A patent application has been filed, and possible interest from biotech companies is being explored.

Potential impact

If further validated, the skin wash device could contribute to more patient-friendly diagnostics and monitoring of skin diseases. Instead of relying only on visible symptoms, clinicians may be able to follow inflammatory processes in the skin more directly. This could support treatment selection, monitoring of treatment response and earlier recognition of changes in disease activity.

For the Flagship, the device is also a building block towards more personalised and preventive healthcare. By making biological signals in the skin easier to measure, researchers can better understand how the body responds to disease, treatment and potentially also environmental factors such as heat and air pollution.

Involved researchers and partners

Researchers involved in this development include Bing Thio, Eveline de Geus, Willem Dik, Robbert Rottier, Sem Koornneef and Nalini Sreeram, from Erasmus MC and collaborating partners. Within the broader Flagship context, Erasmus MC, TU Delft and Erasmus University Rotterdam work together.

Publication: Development of a noninvasive device and method for measuring immune parameters in skin disease