The study from our lab indicated that PTX3 might be expressed mainly by fibroblast in tubulo-interstitial areas of lupus nephritis patients,16 which led to the hypothesis that the pro-inflammatory and pro-fibrotic effects of PTX3 was prevailing under the micro-environment of lupus nephritis, and highlight the associations between PTX3 and interstitial inflammation and fibrosis in situ. This evidence concerns the gene PTX3 and lupus nephritis.