TNFRSF13C and systemic lupus erythematosus: Interestingly, a negative correlation between serum BAFF and sBAFF‐R was detected in HC samples, but was not observed in SLE, potentially suggesting a loss of co‐regulation of these balancing forces in favor of unopposed BAFF action in SLE; this is consistent with the failure to observed increased sBAFF‐R in SLE despite other BAFF receptors being elevated.