Evaluation of the immunological specificity of fluorescein-labelled anti-human IgM conjugates.

The immunological specificity of two anti-IgM fluorescein-labelled antisera was evaluated in gel diffusion, by the direct immunofluorescent technique on characterized bone marrow preparations taken from patients with myeloma and by an indirect staining method employing virus-infected cells and selected post-infection sera. The results show that neither gel diffusion nor direct immunofluorescent methods provide a reliable index of specificity for conjugates to be used in indirect procedures.