Protein and mRNA detection of classic cytokines in corresponding samples of serum, gingival tissue and gingival crevicular fluid from subjects with periodontitis.

Tissue and GCF exhibited overall higher protein concentrations of cytokines than serum. GCF presented good reliability for identifying the target cytokines at protein level, when compared with detecting tissue cytokines at protein level. GCF and tissue presented high sensitivities for detecting cytokines at the protein level, when compared with detecting tissue cytokines at the mRNA level. The sensitivity for the identification of cytokines in the GCF depended on the target cytokine, where IL-6 was the least likely cytokine to be detected in this matrix.