Immunocompatible elastomer with increased resistance to the foreign body response.

Area of Science:

• Biomaterials Science
• Immunology
• Medical Device Engineering

Background:

• Polymeric elastomers are widely used in implantable medical devices.
• Implantation often triggers a foreign body response (FBR), leading to immune rejection and reduced device efficacy.

Purpose of the Study:

• To develop and characterize novel immunocompatible elastomers that resist the foreign body response.
• To evaluate the efficacy of these materials in preclinical models and assess their potential for improving medical device performance.

Main Methods:

• Synthesis of vinyl-based anti-FBR dense elastomers (EVADE).
• Subcutaneous implantation in rodent and non-human primate models to assess FBR suppression (inflammation and capsule formation).
• Analysis of inflammation-related protein expression (S100A8/A9) and assessment of fibrosis.
• Fabrication and testing of continuous subcutaneous insulin infusion (CSII) catheters using EVADE materials.

Main Results:

• EVADE materials effectively suppressed inflammation and capsule formation in rodents for over a year and in non-human primates for over two months.
• EVADE implantation significantly reduced S100A8/A9 protein expression compared to polydimethylsiloxane.
• Inhibition or knockout of S100A8/A9 attenuated fibrosis, identifying it as a potential target for fibrosis inhibition.
• EVADE-based CSII catheters showed improved longevity and performance compared to commercial devices.

Conclusions:

• EVADE materials offer a promising solution for mitigating immune rejection in implantable medical devices.
• These elastomers can enhance and extend the function of various medical devices by resisting local immune responses.
• Targeting S100A8/A9 presents a potential strategy for inhibiting fibrosis associated with medical implants.