Association between COX-2 rs 6681231 Genotype and Interleukin-6 in Periodontal Connective Tissue. A Pilot Study Mesa Aguado, Francisco Luis O'Valle Ravassa, Francisco Javier Rizzo, Manfredi Cappello, Francesco Donos, Nikos Parkar, Mohamed Chaudhary, Navidah Carini, Francesco Muñoz, Ricardo Nibali, Luigi Biopsy Connective tissue Epithelium Hemorrhage Inflammation Monocytes Periodontitis Plasma cells [Objectives] The aim of this pilot study was to investigate associations between IL-6 and COX-2 expression in gingival biopsies and both clinical diagnosis and genotypes in the IL-6 and COX-2 genes. [Design] A case-control study included 41 gingival biopsies obtained from Caucasian patients grouped according to clinical diagnosis of gingival health (n = 10), gingivitis (n = 15) or chronic periodontitis (n = 16). Immunohistochemistry analyses were performed to determine COX-2 expression in lamina propria, IL-6 expression in lamina propria and gingival epithelium and level of inflammatory cell infiltrate. Individual DNA was extracted and genotyped by real-time PCR for IL6 SNPs rs 2069827 and rs 2069825 and for COX-2 rs 6681231. [Results] The percentage of cellular COX-2 expression was associated with the extent of periodontal disease (Arbes index p = 0.026) and inflammatory infiltrate (p<0.0001). No association was observed between IL6 haplotypes and cells positive to IL-6 or COX-2 in gingival tissues. The COX-2 rs 6681231 was associated with cells positive to IL-6 in the connective tissue (p = 0.032). [Conclusions] COX-2 expression in gingival tissues may be a marker of periodontal disease severity. COX-2 rs 6681231 may be associated with IL-6 local production in gingival tissues. 2014-03-19T11:51:52Z 2014-03-19T11:51:52Z 2014 info:eu-repo/semantics/article Mesa, F.; et al. Association between COX-2 rs 6681231 Genotype and Interleukin-6 in Periodontal Connective Tissue. A Pilot Study. Plos One, 9(2): e87023 (2014). [http://hdl.handle.net/10481/30970] 1932-6203 http://hdl.handle.net/10481/30970 eng info:eu-repo/semantics/openAccess Public Library of Science (PLOS)