The Study of Neutrophil Function on the Patients with Periodontal Disease: 1. Role of Serum on NBT Reduction Test

The present study was carried out to examine the phagocytosis and killing functions of neutrophils in patients with periodontal disease. At the outset of this study, we modified the nitroblue tetrazolium reduction test (NBT reduction test) which was established by Baehner and Nathan as a screening test for infectious disease. Then, the NBT reduction test was conducted in which serum (fresh or inactivated) and zymosan which was treated with serum were added to neutrophil suspensions from normal subjects and patients with periodontal disease. The results were as follows: 1. The value of the NBT reduction test in which serum was significantly enhanced, and effect of this serum was not lost when serum was heated with 60°C for 30 minutes. 2. The most value of NBT reduction test was gained when zymosan which was treated with serum was added, and this effect was lost by inactivated to serum. 3. Effect of serum from patients with periodontal disease which acted upon directly neutrophils was significantly lowering as compared with normal subjects. 4. While, effect of serum from the patients which acted upon bacterial opsonization was not significant as compared with normal subjects. From the above results, it was suggested that NBT reduction test of neutrophils was affected by two different components in serum, namely, one of the component acted on directly neutrophils, another component acted on bacterial opsonization.