METHODS: Western blot analysis using anti-KL-6 antibody was performed on serum obtained from 250 healthy subjects.
RESULTS: The efflux behavior of KL-6/MUC1 differed according to the genetically determined molecular sizes in healthy subjects. In subjects having low molecular size, there were significant associations between smoking status, aging, renal function and serum KL-6 concentrations. However, these associations were not significant in the subjects having higher molecular size and the efflux behavior of high molecular size was the only significant determinant of serum KL-6 concentrations.
CONCLUSIONS: This study showed an association between KL-6/MUC1 efflux based on molecular size and serum KL-6 concentrations in healthy subjects. We propose that the molecular size and efflux behavior of KL-6/MUC1 should be considered when interpreting serum KL-6 concentrations.