Nitroblue tetrazolium (NBT) reduction by polymorphonuclear leukocytes on contact with immune complexes in renal...

The reduction of nitroblue tetrazolium (NBT) by polymorphonuclear leukocytes (PMNs) adherent to glomeruli with immune complexes was investigated on nephritic kidney sections or in homogenates of nephritic kidney. The localization of PMNs containing a large amount of reduced NBT (formazan) was exclusively on nephritic glomeruli in the sections and moreover, closely similar to the distribution of immune complexes as defined by an immunofluorescent technique. In comparison with the normal kidney, the PMNs on contact with the nephritic kidney reduced about three times more NBT whether the kidney was sectioned or homegenated. This increase of NBT reduction by PMNs was not influenced by the presence of fresh serum in the reaction mixture. These observations suggest that the oxidative metabolism that reduces NBT in PMNs was increased by immune complexes deposited in the nephritic glomeruli.