[Quantitation of hemagglutinins by the planimetry of precipitated erythrocyte patterns. 4. Application to Lewis blood group determination from saliva and urine specimens and their stains].

Planimetric hemagglutination (PMHA) (Jpn. J. Legal Med., 42, 292-301, 1988) with glutaraldehyde-treated indicator erythrocytes was used to read results of the forensic medical elution test (ET) for the Lewis blood grouping of body fluids. Two variations of PMHA-ET technique were used to determine the Lewis blood group from saliva, urine and their dried stains. In the first technique, saliva, urine samples or saliva extracts from dried stains were coated to the well of a microtiter-plate and then were sensitized with anti-Lea or anti-Leb monoclonal antibodies; these were then followed by antibody elution by heating at 55 degrees C for 30 minutes. This method detected the Lea antigen in 1:5, 120-10, 240 diluted Le (a+) saliva, Leb antigen in 1:10, 240-20, 480 diluted Le (b+) saliva, and detect Lea or Leb antigen of extracts from saliva stains as small as 0.5 X 0.5 cm in size. All 65 saliva samples of Lewis blood groups, 31 Le (a+b-), 29 Le (a-b+) and 5 Le (a-b-), were easily determined and 17 out of 18 urine samples without concentration were also typed. In the second technique, anti-Le antibodies were added to the chopped dried urine stains with no antigen extraction. This technique detected Lea or Leb antigen in the stains 1 X 2 cm in size. The PMHA-ET seems to be more useful for quantitative analysis of the Lewis substances in body fluids than any other conventional methods; this is because of its simplicity, sensitivity and good reproducibility.