[Polyclonal B-cell activation by so-called immunopotentiation (immunostimulants)].

Immuno-augmentation with substances of bacterial origin was studied in vitro for its ability to induce polyclonal B-cell activation. Biostim, Broncho-Vaxom, Omnadin, Paspat and OK 432 were compared for their B-cell mitogenicity with classical polyclonal B-cell activators (Staph. aureus Cowan I, KlebsM, Pokeweed mitogen). B-cell mitogenicity, as measured by 3H-thymidine incorporation into proliferating blood B-cells, was not induced by any of the studied preparations. On the other hand, OK 432 produced a T-cell dependent and Biostim a T-cell independent blood B-cell differentiation in immunoglobulin producing cells. However, the extent of immunoglobulin production was clearly less than with the polyclonal B-cell activator KlebsM. These results demonstrate that, in some of the preparations, in vivo polyclonal B-cell activation can be expected to occur.