Immunohistochemical staining of human alpha-defensin-1 (HNP-1), in the submandibular glands of patients with oral carcinomas.

The purpose of this study was the immunohistochemical localization and distribution of HNP-1 in the submandibular glands of patients with oral carcinomas. Tissue sections were embedded in paraffin, and HNP-1 was immunostained by the streptavidin-biotin coupled peroxidase method. Striated duct cells in the submandibular glands were stained with anti-defensin antibody. Neutrophils and capillary intimal cells were also stained. Defensins (HNPs) are peptides that occur in neutrophils and protect against bacteria and tumor cells. Human alpha-defensin-1 (HNP-1) is such a peptide, possessing both antimicrobial and cytotoxic activities. The presence of HNP-1 in striated duct cells in the submandibular glands of oral cancer patients, suggests a likely role in tumor immunity, for this peptide.