DEMONSTRATION OF THE ACTIVITY OF THE SALIVARY ANTIBACTERIAL FACTOR (S.A. FACTOR) IN HUMAN SUBMANDIBULAR GLAND

Abstract

In previous reports, Zeldow, Matsumura et al., and Kerr and Dogon have reported that an antilactobacillus factor, which required thiocyanate as a cofactor, is present in whole and pure saliva of human beings. Zeldow has referred to this system as the “lactobacillus bactericidin”, whereas Matsumura et al. have termed it the “salivary antibacterial factor or S.A. Factor”. Kerr and Dogon have called it the“antibacterial factor in parotid secretion”.The data suggesting the origin of the S.A. Factor have been described in our laboratory. The activity of the S.A. Factor was observed not in human and some mammalian sera, but in human parotid and submandibular saliva. The similar activity was also demonstrated in the extract of salivary glands of rat, guinea pig and cow. These results suggest that the S.A. Factor may be produced by the salivary gland. The origin of the S.A. Factor, however, is obscure.This paper is concerned with demonstrating the activity of the S.A. Factor in human submandibular glands which was resected surgically from the 8 patients with oral cancer other than salivary gland.Five ml of saline was added to one gram of the minced gland. After homogenization, the homogenate was centrifuged at 13, 000 × g for 30 min at 4 °C. The supernatant was used as the glandular extract.From the experiments the followings were clarified.:1. The activity of the S.A. Factor was not observed in the human submandibular gland extract alone. The content of thiocyanate in the extract was not sufficient (mean value 27 μg/ml) for demonstrating the activity of the S.A. Factor. Moreover, the amount of sulfhydryl groups which depresses the activity of the S.A. Factor was contained in the extract mean value 2.0 × 10-4M).2. When the sufficient amount of thiocyanate (1 mg) was added to the extract, the activity of the S.A. Factor was apparently demonstrated in all cases. Specific activity of the extract was lower (mean value 0.7 × 103) than that of the whole saliva (mean value 2.3 × 103). Furthermore, on addition of subtoxic amonunt of CuSO4 (final concentration 4 × 10 -5M) as a -SH group reagent, the activity of the S.A. Factor was increased twice as much as the activity without CuSO4.