Prior to disease transition, levels of pro-inflammatory mediators SCF, BLyS, MCP-3, and IL-2Rα (Figure 4A), as well as MCP-1 and MIG (Figure S5A) were highest in those lupus relatives in the LAUREL cohort who met clinical ACR criteria at baseline (p<0.05). Here, TNFSF13B is linked to systemic lupus erythematosus.