Soft wireless bioelectronic implant targets the splenic nerve to reduce inflammation

For millions suffering from chronic inflammatory diseases like inflammatory bowel disease (IBD), managing flare-ups often involves powerful drugs with significant side effects. A new study published in National Science Review unveils a pioneering alternative: a soft, wireless implant that treats disease by modulating specific nerves that control immunity.

The research team from Huazhong University of Science and Technology and Tongji Hospital developed a "splenic nerve wireless stimulator" (SpNWS). The key innovation is that the entire device – its electrodes, interconnects, and wireless power receivers – is constructed from a specially engineered conductive hydrogel. This material is as soft as biological tissues, highly stretchable, and can conduct electricity efficiently.

The biggest challenges for long-term neural interfaces are mechanical mismatch and fibrosis caused by rigid implants. Our hydrogel device seamlessly conforms to delicate nerves, operates without batteries, and communicates wirelessly through the skin, which minimizes long-term damage and rejection."

Zhiqiang Luo, corresponding author of the study

The implant is designed to modulate the splenic nerve, a key pathway in the body's inflammatory reflex. In a rat model of chronic colitis, the SpNWS device was implanted and activated wirelessly for 20 minutes daily. The treatment led to remarkable recovery: reduced colon damage, less weight loss, and restored intestinal structure.

Mechanistic studies revealed that the electrical stimulation rebalanced the gut's immune environment. It suppressed pro-inflammatory T-cells (T_H1/T_H17) while promoting anti-inflammatory and regulatory T-cells (T_H2/T_reg). Crucially, after five weeks, the device showed excellent biocompatibility with no significant scar tissue encapsulation, a common problem that leads to the failure of conventional implants.

This work establishes a versatile platform for "electroceutical" therapy. The soft, wireless design could be adapted to interface with various nerves to treat a range of conditions, from rheumatoid arthritis and diabetes to metabolic disorders, ushering in a new era of bioelectronic medicine.