Immunohistochemical localization of CD1a and S100 in gingival tissues of healthy and chronic periodontitis subjects.

OBJECTIVE

The aim of this study was to evaluate the presence and distribution of CD1a and S100 protein markers in states of gingival health and chronic periodontitis in human subjects.

MATERIALS AND METHODS

Gingival tissue samples were derived from 10 healthy and 10 chronic periodontitis-affected human subjects. The presence and distribution of CD1a and S100 protein was assessed using immunohistochemistry, and the cell types involved in their expression was determined.

RESULTS

The presence and distribution of CD1a was confined only to the gingival epithelium, whereas S100 was seen in the epithelium and connective tissue. However, increased expression of both CD1a and S100 protein was seen in periodontitis-affected gingival tissues compared with healthy gingiva. Immunohistochemistry demonstrated that CD1a- and S100-positive cells in the epithelium are Langerhans cells (LCs) and S100 positive cells in the connective tissue are dendritic cells (DCs).

CONCLUSION

Our findings suggest the transition of CD1a-positive LCs to S100-positive DCs from epithelium to connective tissue in response to an antigenic challenge. Demonstration of increased number of S100-positive DCs in the gingival connective tissue in chronic periodontitis possibly suggests their involvement in bone resorption in addition to their antigen presentation property.