Evidence of polymorphonuclear neutrophils (PMN) activation in patients with insulin-dependent diabetes mellitus

Abstract

Polymorphonuclear neutrophils' chemotaxis, surface charge, superoxide anions generation, NBT (nitro blue tetrazolium) reduction and intracellular lysozyme, and β-glucuronidase content were estimated in patients with type I diabetes mellitus in a similar state of metabolic control. The chemotaxis of diabetic cells toward bacterial chemotactic factors was similar to controls, whereas migration toward complement-derived chemoattractants was similar to controls, whereas migration toward complement-derived chemoattractants was significantly reduced. Polymorphonuclear neutrophils isolated from diabetic patients, when unstimulated, produced significantly greater amounts of superoxide anions and reduced NBT more efficiently. They also revealed reduced surface charge and lower intracellular content of lysozyme, whereas β-glucuronidase content was similar to controls. The results obtained seem to indicate that neutrophils in patients with insulin-dependent diabetes manifest signs of being in the activated state. The possible mechanisms of such stimulation are discussed.