In vitro effect of insulin on neutrophil phagocytic and chemotactic functions in insulin dependent and non insulin dependent diabetics [IDDM and NIDDM]

Neutrophil phagocytic and chemotactic activities were measured in vitro in 40 subjects: 10 normal controls, 20 patients with insulin dependent diabetes mellitus [IDDM] and 10 patients with non insulin dependent diabetes mellitus [NIDDM]. Phagocytic and chemotactic activities were measured twice: first, before adding insulin and secondly, 30 minutes for the chemotactic activity, to determine the direct effect of insulin on neutrophil function. A significant impairment of phagocytosis in both IDDM and NIDDM patients was observed. Phagocytosis was not altered by the in vitro addition of insulin. It is explained by the fact that insulin does not act directly on the cells but by regulating the blood glucose level through inhibiting glycogenesis and lipolysis. Patients with IDDM showed no significant correlation between fasting blood glucose and the phagocytic index, but a significant correlation was observed between the glucose and the phagocytic index, but a significant index. However, patients with NIDDM showed no significant correlation between fasting blood glucose and phagocytic index and no correlation between the duration of the disease and the phagocytic index. Also no impairment of PMN chemotaxis in vitro was observed in either IDDM or NIDDM patients before or after insulin addition