PTX3 and lupus nephritis: In renal pathological data, the levels of serum PTX3 in different pathological classes of lupus nephritis were as followings: 2.899 (0.953–15.533) ng/ml in class II, 2.505 (0.382–13.311) ng/ml in class III, 4.168 (0.355–56.376) ng/ml in class IV and 2.366 (0.399–11.082) ng/ml in class V. There were significant differences in serum PTX3 levels among various pathological classes, which was the highest in class IV group (P = 0.009).