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 pe riapical lesions, an immunohistochemical technique was used to study its di stribution. Study design. Twenty periapical lesions-16 periapical granulomas and 4 radi cular 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 fibr ous lining around each granuloma were positive, showing an immune reactive pattern directly correlated with the dimension of the lesion. Epithelial re sts of Malassez were strongly positive; the reaction product was also evide nt in the epithelial lining of the cysts. Blood vessels, mainly observed ar ound the lesion, were immunoreactive for CD44. Conclusions. Our findings demonstrate that CD44H and its V3 Variant are exp ressed in at least 3 different tissue types of periapical lesions. These gl ycoproteins may be involved in different steps of periapical lesion pathoge nesis and evolution.