Our findings suggest that increased CD68 immunostaining associated with TNF-α cytokine in RCs results in a greater differentiation of the M1 phenotype.
Immunohistochemical staining showed that the inflammatory response including up-regulation of TNF-α and the infiltration of T cells, was severe in granuloma and restricted in periapical cyst.
Based on these findings, we emphasize that RCs and PGs have a similar expression of inflammatory mediators (COX-2 and TNF-α) although the secretion of TNF-α by macrophages and of COX-2 by several cells was higher in PGs, indicating a greater inflammatory response in these lesions.
The expression of such cytokines, namely, interleukin-1beta, IL-1beta, IL-6, IL-8, IL-10, tumour necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), transforming growth factor-beta1 (TGF-beta1), and granulocyte-macrophage colony-stimulating (GM-CSF) mRNA, in nine radicular cysts was examined and compared with that detected in six specimens of healthy gingival mucosa.
The expression of mRNA encoding the inflammatory cytokines interleukin-1alpha (IL-1alpha), interleukin-1beta (IL-1beta), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor alpha(TNF-alpha) have been examined in radicular cysts by in situ hybridization.