In addition, the positive association between M3R IgG3 and CXCL Sa-C-2 (GCP-2; r = 0.789, P = 0.002) in its turn correlating with RI, suggests that anti-M3R IgG3 has a role in connecting different SS-related disease manifestations. Here, IGHG3 is linked to synovial sarcoma.