Salivary cortisol is commonly used as a clinical biomarker of endocrine status 
and also as a marker of psychosocial stress. Annexin-A1 (AnxA1) is an 
anti-inflammatory protein whose expression is modulated by glucocorticoids. Our 
principal objectives were to (i) detect the presence of and (ii) measure AnxA1 
protein in whole human saliva and to (iii) investigate whether salivary cortisol 
and AnxA1 are correlated in healthy humans. A total of 37 healthy participants 
(male and female) were used in the study. Saliva was collected using salivette 
tubes. Salivary cortisol and AnxA1 protein were sampled at between 3 and 6 time 
points over 24h and measured for cortisol and AnxA1 protein using specific 
ELISA's. The presence of salivary AnxA1 protein was confirmed by Western 
blotting. AnxA1 protein is detectable in whole human saliva, as detected by 
Western blot analysis and ELISA. A diurnal rhythm was evident in both salivary 
cortisol (P<0.01) and AnxA1 (P<0.01) and was defined as a significant difference 
in time 0 (waking) samples compared to 'bed' (2300 h) samples. AnxA1 protein did 
not exhibit an awakening response (P>0.05), whereas salivary cortisol was 
significantly elevated between time 0 and 30 min post waking (P<0.001). AnxA1 
protein correlates positively with salivary cortisol, indicating that cortisol 
is most likely a regulator of AnxA1 in human saliva.