The relationship between secretory immunity, mood and life-events

Twelve subjects volunteered to take part in a short trial involving daily life-event and mood recording over a period of up to two weeks. On each day subjects also provided timed saliva samples. Aggregated data across the trial period revealed that unstimulated secretion rate of secretory immunoglobulin A from whole saliva correlated strongly and significantly with net desirable event reporting, defined as a subject's tendency to report relatively frequent desirable events and relatively infrequent undesirable events. Correlations with positive and negative mood were insignificant, although the pattern of results was in line with hypotheses. Within-subject analyses revealed a totally contrary pattern of results. In particular, negative mood was significantly associated with higher sIgA secretion rate. Analyses involving total sIgA concentration paralleled those using secretion rate. Results are discussed in relation to psychoneuroimmunological models of illness vulnerability, particularly upper respiratory infection, and previous findings in regard to secretory immunity.