ABSTRACT
The influence of B-activin, the preparation of immunomodulating myelopeptides, on the level of antibody formation after the primary immunization of mouse splenocyte cultures with immobilized antigens has been studied. The treatment of the cells with B-activin on the third day of their cultivation in the presence of peroxidase immobilized on polystyrene or protein M1 of influenza virus has been found to increase antigen-specific antibody formation by several times, while having practically no effect on the total level of IgG secretion. The stable level of the stimulation of antibody formation and the possibility of its quantitative evaluation in the enzyme-linked immunosorbent assay makes this immune response inducing system a convenient model for testing the biological activity of myelopeptides and other immunostimulators.