[Fluorescent FAB-fragments of antibodies. Comparative assessment and utilization in immunofluorescent analysis]

The authors present the results of a comparative study of the immunofluorescent activity and the specificity of fluorescent Fab-fragments of antibodies to R. prowazeki, D. sibericus, and B. pertussis obtained by the enzymatic hydrolysis of specific immunoglobulins with papain. Fluorescent Fab-fragments of antibodies possessed the same sensitivity and specificity as the homologous fluorescent antibodies, but had an advantage of a much weaker capacity to nonspecific fluorescence and a relatively higher staining properties. Fluorescent Fab-fragments of antibodies, in contrast to the fluorescent antibodies of the same specificity, permitted to detect the antibody searched in the concentrated crude material, and thus increased the possibilities of the immunofluorescent analysis.