Functional integrity of gingival crevicular neutrophil polymorphonuclear leucocytes as demonstrated by nitroblue tetrazolium reduction.

Abstract

Gingival crevicular neutrophils were collected from 20 healthy subjects and their ability to reduce nitroblue tetrazolium was investigated by means of a semi‐quantitative histochemical test. 78.04 % (± s.e.m. 0.8 %) of the cells were vital. 42.9 % (± s.e.m. 3.3 %) of the crevice neutrophils were NBT positive as compared to 5.6% (± s.e.m. 0.89%) of unstimulated peripheral venous blood neutrophils from the same patients (p < 0.001). No difference between male and female was found. The results indicate a stimulation of crevicular neutrophils by bacteria. Furthermore, a slight correlation between blood and crevicular neutrophil activity in each individual was found, suggesting that even in the normal state some antigen or other bacterial product in the circulation is capable of stimulating the neutrophils.One patient with hereditary cyclical neutropenia, shown to have a greatly reduced number of crevicular cells, had normal activity of both blood and crevicular neutrophils as measured by this test. These findings, compatible with known immunological results, are compared with the neutrophil function test results in this patient and two other neutropenic subjects.This study supports the view that the gingival crevicular neutrophil is a functional cell capable of contributing towards host defense.