[Concentration of serum proteins and blood group substances in human saliva. 1. Quantitation method and variation of secreting quantities among daily life].

Immunoelectrophoretic analysis of 100 times concentrated human saliva specimens showed marked individual differences in the content of albumin (Alb), IgA, IgG and transferrin (Tf). We concluded that the planimetric measurement of the precipitated area produced by latex-agglutination or hemagglutination on microtiter plates was an appropriate method for quantitating these serum proteins or ABO and Lewis blood group substances in saliva. Nonspecific agglutinating activity caused by mucinous substances in saliva was prevented when the saliva was once stained on a filter paper then dried and extracted with a buffer solution. Quantities of the serum proteins and blood group substances in saliva decreased immediately after meals and gradually increased 2 to 3 hours thereafter. The ratios of IgA/Alb, IgA/IgG and IgG/Alb did not differ remarkably with the time of sample collection. Saliva from parotid and submaxillary-sublingual glands contained similar quantities of the serum proteins, whereas more ABO and Lewis blood group substances were found in saliva from submaxillary-sublingual glands than in that from parotid gland.