Molecular forms of soluble HLA in body fluids: potential determinants of body odor cues

The major histocompatibility complex (MHC) has been linked to encoding for individual olfactory identity. Experiments in mice and rats proved that behavior and mating were, at least in part, determined by genes within the MHC. This study was aimed at investigating whether sHLA are excreted in human urine, saliva and sweat. In particular examination of the molecular forms in these fluids would give clues to whether break down forms of soluble MHC molecules might participate in shaping behavior. Major bands of 45, 40, and 23 kD were detectable. Increased levels of sHLA were measured using a quantitative ELISA in urine shortly before ovulation decreasing to normal levels thereafter. In animal models strain specific MHC-linked odor cues have been detected in urine. Thus, excretion of sHLA in urine might indicate a similar role for these molecules in humans.