Similarly, an injectable and biomolecule-delivery of poly(L-lactic acid) (PLLA) nanofibrous spongy microspheres (NF-SMS) promote Treg enrichment, amplification, and Treg-mediated immunotherapy against bone loss in a mouse model of periodontitis via significantly releasing miRNA and IL-2/TGF-β (75). This evidence concerns the gene TGFB1 and periodontitis.