Abstract

Investigations into the possibility that X (an antigen consistently present in aspirated odontogenic keratocysts, but not in most fluids from other cyst types), represented a keratinocyte component failed to identify the antigen as a keratin, involucrin, or one of the blood group substances. Antigen X was detected in human mixed and parotid saliva and in colostrum, as well as in a commercially obtained preparation of colostral IgA. The antigen was similar biochemically to both secretory component and lactoferrin but proved to be identical antigenically with lactoferrin. The origin of lactoferrin in keratocyst fluids remains uncertain, though the lining epithelium seems a more likely source than does the very variable, and often negligible, inflammatory infiltrate found in these lesions.