Distribution of lactoferrin in human salivary glands.

An immunoperoxidase technique was used to study the distribution of lactoferrin (LF) in human salivary glands from autopsy tissues fixed in Carnoy's fluid for the optimal preservation of LF antigenicity. Specific LF staining was seen in the intralobular ducts of all salivary glands but never in the interlobular ducts; acinar LF was detected in most serous demilunes of the mixed glands and in some but not all acinar cells of the pure serous glands. No LF was detected in the acinar cells of the pure mucous glands. In the oral tissues studied the only additional cells containing LF were polymorphonuclear leucocytes. Whether LF in the salivary glands is synthesized locally and/or ultrafiltrated from the blood is at present unclear. Present evidence indicates that the biological role of salivary LF is antibacterial.