Comparing the efficacy of human serum, plasma, and saliva on neoplastic and non-neoplastic epithelial cell viability.

OBJECTIVES: This study aimed to compare the use of different human biological fluids in the viability of epithelial and oral cancer cells. DESIGN: For this purpose, human serum (HSR), plasma (HPL), whole saliva (HWS), and centrifuge saliva (HCS) samples were tested at different concentrations (5%, 10%, 15% and 20% volume per volume (v/v) and periods (24 h, 3, 5 and 7 days) in the culture of normal oral and skin epithelial cells (NOK-SI and HACAT, respectively) and cell lines derived from oral squamous cell carcinoma (SCC9, SCC25 and Cal27). MTT and clonogenic assays were used to analyze cellular metabolic activity and colony formation potential, respectively. Fetal Bovine Serum (FBS) at 10% (v/v) was used as a control. RESULTS: HSR was the most effective fluid in maintaining metabolic activity in SCC9, SCC25, Cal27, and HACAT cells in different culture times. HPL generally resulted in lower cellular metabolic activity than HSR and FBS across the experimental conditions evaluated. HCS and HWS induced a lower viability compared to FBS in all cell lines tested in the long term. However, HCS and HWS maintained the metabolic activity of NOK-SI, SCC25, and Cal27 cells for shorter periods. In clonogenic assays, HSR induced colony formation in SCC25, NOK-SI, and HACAT cells at different culture times. CONCLUSIONS: HSR is the most effective biofluid for maintaining the viability of both oral cancer and normal epithelial cells, a property that makes it potentially applicable in translational research.