The impact of saliva collection and processing methods on CRP, IgE, and Myoglobin immunoassays

Saliva samples were collected from participants (n？=？25, ages 20–35 years) using the following methods: no stimulation (resting/unstimulated), mechanical, and acid stimulation. The saliva was prepared for analysis by: unprocessed, post standard centrifugation in a container without any additives, and centrifugation using Centrifugal Filter Unit (Amicon？ Ultra-0.5). AlphaLisa？ assays were used to measure the levels of C-Reactive Protein (CRP), Immunoglobin (IgE) and myoglobin in saliva samples.Saliva flow rates were lowest with the resting/drooling collection method. The lowest total protein concentration was with acid stimulation. Unstimulated and mechanically stimulated collections produced no effect on the CRP and IgE levels while myoglobin levels were highest with the unstimulated collection. Acid stimulation had a negative impact on the measured concentrations of IgE and myoglobin (except for CRP levels).Mechanical stimulation was the most viable option for collecting saliva without affecting the levels of CRP and myoglobin. The processing methods had an adverse effect on the concentration of total protein as well as on CRP and IgE concentrations.Human saliva is a unique biological fluid with numerous functions within the oral cavity, predominantly facilitating the maintenance of oral health and creating an appropriate ecological balance in the mouth [1]. Human saliva mirrors the body’s health and wellbeing and approximately 20-30% of proteins [2,3] found in blood are also present in saliva, highlighting the diagnostic potential of this biological matrix. The advantages of using saliva as a diagnostic body fluid compared to blood are (a) sampling is non-invasive, rapid and allows multiple sample collections; (b) the collection process is relatively simple, safer and painless and ideal for population based screening programs; (c) sampling can be carried out by patients or carers to facilitate self-management of disease monitoring at home or care/clinical setting