Immunohistochemical Evaluation of Angiogenesis and Tryptase-positive Mast Cell Infiltration in Periapical Lesions

Introduction: Several studies have linked mast cells (MCs) with angiogenesis. The aim of this study was to correlate angiogenesis with MCs in radicular cyst (RC) and periapical granuloma (PG) cases. Methods: Forty-eight samples of periapical lesions, diagnosed as RC (n = 24) and PG (n = 24), were included. The microvessel density and microvessel area measured through the immunoexpression of CD105 and CD34 and the MC density measured through the immunoexpression of tryptase were performed. Results: MCs were detected in all RCs and PGs (P =.888), mainly in perivascular location and within fibrous stroma. CD34 stained all vessels present in all RC and PG cases. CD105 revealed differential expression, stained preferentially vessels of greater lumen, and showed variable location inside fibrous stroma in both lesions. There was a significant difference of microvessel density determinate by CD34 and CD105 in RCs (r = 0.634, P =.002) and in PGs (r = 0.5709, P =.0036). The difference was also observed when comparing age of the patient in both lesions. Considering the microscopic association between highest concentration of MCs and vascularization, CD105-positive vessels in 50% of RCs and 70.8% of PGs and CD34-positive vessels in 66.7% of RCs and 87.5% of PGs showed areas of close association with MCs. Conclusions: These results suggest differential expression of CD105 within RC and PG. There is no difference in angiogenesis and MC density between RC and PG. Moreover, because of the association between MCs with vessels and fibrous stroma, other possible roles of tryptase, in addition to the angiogenic properties, should also be considered. (J Endod 2011;37:1642-1646)