Kitagawa A, et al. - Given that Mac-1 comprises a unique α subunit (CD11b) complexed with a common β2 subunit, which are released along with CD16b from specific leukocyte subsets under inflammatory conditions including glomerulonephritis, researchers studied the relationship of urinary CD11b and CD16b with histopathological activity in 272 patients with biopsy-proven glomerular diseases, including 118 with lupus nephritis (LN). Through enzyme-linked immunosorbent assay, urine CD11b and CD16b were measured. Investigators observed that urinary levels of both markers were increased in LN, but only urinary CD11b was related to the number of glomerular leukocytes and with overall histopathological activity. According to findings, urinary CD11b could be a useful biomarker to estimate histopathological activity, especially glomerular leukocyte accumulation, in LN.