IgG4-positive plasma cells are more often detected in chronic periapical lesions arising from permanent rather than primary teeth.

AIM: To characterize plasma cell subsets in chronic periapical lesions affecting permanent and primary teeth. METHODOLOGY: Only chronic periapical lesions without root canal treatment were selected. Twenty-one radicular cysts and 7 periapical granulomas affecting permanent teeth and 19 radicular cysts and 4 periapical granulomas affecting primary teeth were assessed for immunoglobulin (Ig) light chain (kappa and lambda), Ig heavy chain (IgG, IgG4, IgA, IgM and IgD) and plasma cell immunohistochemical markers (MUM1/IRF4, EMA and CD138). The data acquired were analysed by Student's t test, Mann-Whitney U, Friedman test followed by Dunn's multiple comparison test and Spearman's rank correlation. RESULTS: All cases were polyclonal (having similar kappa/lambda light chain ratios). IgG was most abundant compared to other Ig heavy chains (all, P < 0.001); like Ig light chains, but unlike IgA, there was greater expression of IgG in the primary compared to the permanent dentition, for both radicular cysts (P < 0.001) and periapical granulomas (P = 0.53). Notably, IgG4 expression was greater in the permanent than the primary dentition, for both radicular cyst (P < 0.05) and periapical granuloma (P = 0.65). IgM and IgD expression was scarce and variable, whereas plasma cell populations were detected efficiently through EMA, CD138 and MUM1/IRF4 markers, the latter being more sensitive in both dentitions. CONCLUSIONS: There were slight variations in the Ig light and heavy chain profiles in chronic periapical lesions when comparing the permanent and primary dentitions. The ability of IgG4+ plasma cell infiltration to modulate inflammatory responses in chronic periapical lesions arising from permanent as opposed to primary teeth should be considered in future studies.

Evaluation of MMP-1, MMP-10, TIMP-1, a-SMA and TGF-b1 in angiofibromas of tuberous sclerosis.

AIM: Tuberous sclerosis is a neurocutaneous syndrome characterized by affect multiple organs such as brain, kidneys, heart, eyes, lungs and skin. The aim of this study was to analyze the pattern of immunolocalization of markers MMP-1, MMP-10, TIMP-1, α-SMA and TGF-ß1 in oral and facial angiofibromas in individuals affected by tuberous sclerosis. METHODS: Microscopical analyses on hematoxilin-eosin and immunohistochemistry reactions were performed to analyze the previously cited biological markers pattern in orofacial angiofibromas. RESULTS: Reactivity was observed for MMP-1, MMP-10 and TGF-ß1, in addition to negative for TIMP-1 and α-SMA, except perivascular and epithelial staining for this. Concerning the intensity, a strong marking for MMP-1 in the basal layer of the epithelium, and a slight positivity in the suprabasal layers predominated. MMP-10 was slightly expressed in all epithelial layers. The connective tissue showed slight to moderate reactivity for MMP-1 and MMP-10. TIMP-1 demonstrated slight to moderate marking in the various layers of a single lesion and to TGF-ß1 expression showed varied in intensity staining both between lesions and between tissue layers. CONCLUSION: MMP-1, MMP-10 and TGF-ß1 exhibited reactivity in oral and cutaneous angiofibromas with heterogeneous distribution patterns among both tissue elements analyzed in the intensity of marking the same among the specimens. TIMP-1 showed reactivity predominantly negative in the specimens analyzed and α-SMA presented restricted to epithelial and perivascular regions of these lesions.