Published online by Cambridge University Press: 15 May 2009
Quantitative methods have been used in several investigations by Kabat and his colleagues (1945–50) in the study of serological relations of various preparations of blood-group substances. The investigations have taken twoforms: (1) the amounts of antibody nitrogen precipitated from a standard volume of an antiserum by varying amounts of the blood-group substances have been plotted against the amount of blood-group substance added; (2) the hexosamine has been measured in the precipitates formed with antiserum in the zone of antibody excess and the ratio of hexosamine precipitated to hexosamine in the blood-group substance added has been calculated; the amount of methyl-pentose precipitated has also been measured (Kabat, Baer &Knaub, 1949) and the ratio of methyl-pentose precipitated to methyl-pentose added hasbeen calculated.