A symposium update on the key perspectives in systemic sclerosis and systemic lupus erythematosus.

The fourth LBMR-Tim (Toulouse Referral Medical Laboratory of Immunology) symposium was convened on December 15th, 2025, in Toulouse, France, to discuss recent advances in the understanding and management of systemic sclerosis (SSc) and systemic lupus erythematosus (SLE). Pathophysiological mechanisms underlying SSc and SLE were discussed from a genetic perspective, with particular emphasis on the X-chromosomal TLR7/TLR8 locus and the interferon signaling pathway. Cellular aspects were explored, highlighting the critical roles of regulatory T cells (Tregs), exhausted T cells, macrophage polarization, and endothelial cells. At the translational research frontier, significant initiatives are underway within the framework of the European Autoimmunity Standardization Initiative (EASI) aimed at enhancing routine biomarker application for diagnosis, disease monitoring, and prognostic considerations. Emerging biomarker candidates promise potential for improving prognostic assessment and follow-up in lupus nephritis (e.g., urinary sCD163/creatinine ratio), cardiovascular complications and vasculopathy associated with SSc (e.g., dephosphorylated-uncarboxylated matrix Gla protein [dp-ucMGP] and endothelial progenitor cells), as well as therapeutic response evaluation (e.g., IGRA-PHA assays and proteomic methodologies). Therapeutically, a paradigm shift is underway with the development of efficacious mono- and multi-targeted antibody treatments alongside cellular therapies designed to eliminate B cells through chimeric antigen receptor (CAR) T cells or to re-establish immune regulation through Treg restoration. The integration of these therapeutic modalities necessitates further investigation to optimize individualized patient selection and management strategies. The multidisciplinary expert panel advocates for a comprehensive approach encompassing fundamental science, translational research, clinical expertise, and therapeutic innovation to advance in the management of these two complex syndromes.