Furthermore, Surface plasmon resonance (SPR) revealed the direct interaction between Chi3L1 (15.625–1000 nmol L−1) and IL‐17RA (Figure 5L; Table S3, Supporting Information).[46] Co‐immunoprecipitation (Co‐IP) assays suggested that Chi3L1 interacts with IL‐17RA in cell lysates obtained from SSc DFs treated with Chi3L1 (Figure 5M,N). Here, CHI3L1 is linked to systemic sclerosis.