A new study published in the journal Science identifies immune cells that help facilitate tissue repair in the presence of biomaterial scaffolding. The findings could support tissue healing following events such as infections, surgeries and trauma.
Previously, immune responses to biomaterials were associated with rejection; however, some evidence suggests that subsets of the immune system may actually facilitate regeneration following treatment with biomaterial scaffolding. To gain more insights, Kaitlyn Sadtler et al. monitored the immune response of mice to different types of biomaterial scaffolding – bone, muscle and collagen. Analysis of gene expression of tissue surrounding the scaffolding revealed upregulation of interleukin-4 (IL-4), a signaling molecule associated with type 2 helper T cells (TH2).
Through a series of experiments with mice lacking IL-4 and with impaired TH2 cells, the authors demonstrate how these immune components facilitate tissue repair around biomaterial scaffolding. Based on their work, it appears that TH2 cells use IL-4 to recruit macrophages, which help mitigate the inflammation process and clear dead cells from the site of injury. These results suggest that therapeutic targeting of TH2 cells may facilitate better tissue repair following treatment with biomaterial scaffolding. A Perspective titled “A scaffold immune microenvironment” by Stephen Badylak provides more context.