[Molecular weight heterogeneity of isolated antigenic complexes and their immunochemical activity]

Antigenic complexes extracted from S. typhi Ty24446 in tryptic proteolysis displayed heterogeneity by molecular weight. The O-antigenic activity of the preparation was associated with the components with a mol. weight of 6.7-10(4)--2-10(6), Vi-antigenic activity--with the components with a mol. weight of 6.7-10(4)--2-10(6) and the components with a mol. weight of 1.75-10(4)--6.7-10(6). Components with a mol. weight below 1.75-10(4) possessed no Vi-antigenic activity. Correlations between the high- and low-molecular components in the "tryptic" antigen depended on the regimen of proteolysis.