Langerhans cells in odontogenic epithelia of odontogenic fibromas

Langerhans cell (LC) is an antigen-presenting cell that is very important for T-cell-mediated immune reactions. Our previous studies have shown the presence of LCs in some odontogenic tumors and cysts. In this study, we further examined the presence of LCs in odontogenic epithelia of 16 odontogenic fibromas (OFs).

Anti-CD1a and anti-S-100 immunostains were used to detect the presence of LCs in nests or strands of odontogenic epithelia of 16 OFs.

These 16 OFs included 10 peripheral OFs excised from seven male and three female patients (mean age, 38 years) and six central OFs (including one recurrent OF) removed from five male patients (mean age, 28 years). Of the 10 peripheral OFs, six were found on the mandibular gingiva and four on the maxillary gingiva. Four central OFs were located in the maxilla and two in the mandible. We found that both anti-CD1a and anti-S-100 immunostains had an equal ability to identify LCs in OFs. Positively stained dendritic LCs could be detected in nests and strands of odontogenic epithelia in nine (six peripheral and three central OFs) of the 16 OFs. In five peripheral OFs, dendritic LCs were found in occasional nests or strands of odontogenic epithelia. In one peripheral and three central OFs, dendritic LCs could be detected in at least half of the nests or strands of odontogenic epithelium in the tissue section.

LCs can be detected in the nests or strands of odontogenic epithelia in approximately 60% of the 10 peripheral OFs and approximately 50% of the six central OFs detected.