Oral sampling methods are associated with differences in immune marker concentrations.

OBJECTIVE: To determine whether the concentration and distribution of immune markers in paired oral samples were similar.

STUDY TYPE: Clinical research.

STUDY DESIGN: Cross-sectional study.

METHODS: Paired saliva and oral secretions (OS) samples were collected. The concentration of immune markers was estimated using Luminex multiplex assay (Thermo Fisher Scientific, Waltham, MA). For each sample, the concentration of respective immune markers was normalized to total protein present and log-transformed. Median concentrations of immune markers were compared between both types of samples. Intermarker correlation in each sampling method and across sampling methods was evaluated.

RESULTS: There were 90 study participants. Concentrations of immune markers in saliva samples were significantly different from concentrations in OS samples. Oral secretions samples showed higher concentrations of immunoregulatory markers, whereas the saliva samples contained proinflammatory markers in higher concentration.

CONCLUSION: The immune marker profile in saliva samples is distinct from the immune marker profile in paired OS samples.

LEVEL OF EVIDENCE: 2b. Laryngoscope, 128:E214-E221, 2018.