Though monocyte lineage cells have also been reported as CXCL13-producing cells in murine lupus models in the kidney [54, 55], the expression of CXCL13 in fibroblasts was not examined in these studies, and the relative contribution of hematopoietic cells and non-hematopoietic cells to overall CXCL13 expression in the kidney has yet to be determined in this model. This evidence concerns the gene CXCL13 and systemic lupus erythematosus.