Biological targeted therapy for lupus nephritis-the role of BLYS and APRIL.

Lupus nephritis (LN) is a frequent and serious complication of systemic lupus erythemosus (SLE). Both innate and adaptive immunity play essential roles in the initiation and progression of LN. B-lymphocyte stimulator (BLYS) and a proliferation-inducing ligand (APRIL), members of the tumor necrosis factor superfamily, bind to receptors such as B-cell activating factor receptor 3 (BR3), transmembrane activator and CAML interactor protein (TACI), and B-cell maturation antigen (BCMA). BLYS and APRIL are often overexpressed in LN, showing a positive correlation with disease activity. Therapeutic targeting of BLYS/APRIL has demonstrated efficacy in reducing LN activity. Traditional immunosuppressants often have multiple contraindications and side effects due to their broad immune-suppressing effects. Recently, B-cell-targeting agents, including rituximab, belimumab, as well as telitacicept have shown promising efficacy and reduced side effects in LN treatment. Telitacicept, a novel biological agent, has been approved firstly effective for SLE treatment in China. This review focus on the role of BLYS and APRIL in LN development and progression, alongside clinical data on the targeted therapies of above biologicals.