Optimization of buffer solutions to analyze inflammatory cytokines in gingival crevicular fluid by multiplex flow cytometry

ABSTRACT

OBJECTIVE: the aim of this study was to test two buffer solutions in order to attain a reliable and reproducible analysis of inflammatory cytokines (IL-Beta, IL-6, TNF-alpha, OPG, OPN and OC), in gingival crevicular fluid (GCF)by flow cytometry. MATERIAL AND METHODS: GCF samples from healthy volunteers were collected with perio-paper strips and diluted either in phosphate buffered saline (PBS) or Tris-HCl buffer, with and without protease inhibitors (PI). Cytokine immunoassays were carried out by flow cytometry (Luminex Xmap 200) generating standard curves. RESULTS: standards curves generated with the use of phosphate-buffered saline (PBS) demonstrated best adjustment for cytokines IL-1beta, IL-6 and TNF- α levels, when using Tris-HCl (p < 0.05). CONCLUSIONS: The use of PBS buffer with the addition of PI provided reliable measurements of inflammatory bi-omarkers in GCF samples of healthy volunteers