Geographic tongue: assessment of peripheral nerve status, Langerhans cell, and HLA-DR expression.

OBJECTIVES

The objectives of this study were to determine whether geographic tongue (GT) is an antigen-driven condition by assessing Langerhans cell numbers and the expression of human leukocyte antigen (HLA)-DP, -DQ, and -DR in the epithelium of GT and to assess peripheral nerve status for any possible damage/injury association by quantifying neurite area in connective tissue in GT.

STUDY

DESIGN

Randomly selected samples of GT were examined by using routine immunoperoxidase staining methods to S100 protein, neurofilament, CD1a, and HLA class II. The Student t test and Mann-Whitney U test were used to assess statistical significance.

RESULTS

Langerhans cell numbers were found to be increased in GT. HLA expression was also seen in Langerhans cells and inflammatory cells and in the spinous layer and parabasal epithelial cells in 2 samples of GT. Total nerve tissue, based on area measurements, was not significantly different between GT and control tissues.

CONCLUSIONS

The increase in Langerhans cells suggests that GT is a condition that is likely driven by an unknown external antigen. Peripheral nerve damage was not apparent, suggesting that this is not a mechanism whereby patients with GT become symptomatic.