Most times the fusion of peptide and Fc reduced the efficacy of the active peptide in vivo [26]; however, in our research, HM-3-Fc showed better efficacy than HM-3 in the improvement of arthritis index (Figure 8), TNF-α expression by macrophages (Figure 5) and CD31 expression in the immunohistochemical analysis (Supplementary Figure S7C). The gene discussed is PECAM1; the disease is arthritic joint disease.