B2M and focal segmental glomerulosclerosis: As the nature of ß2‐microglobulin (B2 M) is pro‐inflammatory, its mRNA expression in cells of the urinary sediment is higher in DKD and FSGS in comparison with healthy patients, which may be reflecting to a tubulointerstitial injury promoted by albumin,30 and in our results, B2 M is high expressed in podocyte of glomerulonephritis rather than tubule, so the role of B2 M in podocyte needs to be further investigated.