Vaccines are a powerful tool for preventing and treating major diseases such as infectious diseases and cancer. Traditional intramuscular or subcutaneous injection methods are notably painful, rely on specialized medical personnel, and their immunological efficacy is often limited by the inability of antigens to be effectively captured and presented by antigen-presenting cells, as well as the rapid clearance of antigens from the body. The site of antigen delivery and its release kinetics are crucial for eliciting an adaptive immune response.

A research team led by Dr. CHANG Hao from the Hangzhou Institute of Medicine, Chinese Academy of Sciences, has developed a separable nanocomposite hydrogel microneedle patch that enhances adaptive immune responses through intradermal delivery and sustained release of antigens. 

This study was published in Acta Biomaterialia.

The introduction of nanoclay (Laponite, LAP) not only enhances the mechanical strength of the microneedles but also promotes antigen uptake and maturation of dendritic cells (DCs). Additionally, LAP can adsorb antigens through electrostatic interactions, significantly delaying the release of antigens. 

Mouse immunization experiments have shown that the intradermal and sustained release of antigens using nanocomposite hydrogel microneedles induces a more potent and long-lasting adaptive immune response compared to traditional injection methods. 

Furthermore, no significant toxicity or adverse reactions such as inflammation were observed in long-term immunization studies, indicating good biocompatibility of the nanocomposite hydrogel microneedles. With its ease of use, painlessness, and minimally invasive nature, the nanocomposite hydrogel microneedle patch is expected to greatly improve the accessibility and effectiveness of vaccination.

Original link: https://doi.org/10.1016/j.actbio.2024.07.031