IL-1β and IL-17 cannot only induce the proliferation of FLSs, but also stimulate the angiogenesis by promoting the expression of vascular endothelial growth factor (VEGF), IL-8, MPPs and other forms of angiogenesis, leading to the formation of pannus and synovial lesions of RA (Kim et al., 2017; Wang Y. et al., 2017). Here, IL17A is linked to rheumatoid arthritis.