Inhibitory effects of whole and parotid saliva on immunomodulators

Based on the presence of cytokines in whole saliva and their association with resistance and susceptibility to infectious disease, the present study was designed to evaluate the diagnostic potential of a large panel of cytokines and chemokines in saliva. Despite the endogenous presence of Th1/Th2 and pro-inflammatory cytokines and several chemokines in whole and parotid saliva of most individuals tested, the detection of known concentrations of several recombinant cytokines and chemokines was inhibited immediately following their addition to each type of saliva. In contrast, purified immunoglobulins were unaffected by either whole or parotid saliva. Further studies revealed that the inhibition of immunoreactivity involved sequestration of the majority of cytokines affected and degradation of chemokines. These results suggest that absolute concentrations of cytokines/chemokines may not be fully detectable in saliva. Therefore, the diagnostic value of any cytokine/chemokine is questionable and should be evaluated independently as such.