Immunolocalization of CD44 adhesion molecules in human periradicular lesions

Objective. The hyaluronate receptor CD44 is a cell surface protein that is involved in several functions. To elucidate whether CD44 plays a role in periapical lesions, an immunohistochemical technique was used to study its distribution. Study design. Twenty periapical lesions-16 periapical granulomas and 4 radicular cysts-constituted the sample. Formalin-fixed/paraffin-embedded tissue sections were studied by means of immunohistochemistry for the presence of the standard CD44H form and its V3 splicing variant. Results. Immunohistochemical staining for CD44H and CD44V3 was observed on epithelial, endothelial, and connective tissue cells. The cells of the fibrous lining around each granuloma were positive, showing an immune reactive pattern directly correlated with the dimension of the lesion. Epithelial rests of Malassez were strongly positive; the reaction product was also evident in the epithelial lining of the cysts. Blood vessels, mainly observed around the lesion, were immunoreactive for CD44. Conclusions. Our findings demonstrate that CD44H and its V3 Variant are expressed in at least 3 different tissue types of periapical lesions. These glycoproteins may be involved in different steps of periapical lesion pathogenesis and evolution.