Studies on the adjuvant action of beryllium. III. The activity in the plasma of lymph efferent from nodes stimulated with beryllium.

Efferent lymph from the popliteal or prefemoral lymph nodes was collected from unanaesthetized sheep before and after the injection of insoluble Be(OH)2 into the subcuticulum that was drained by the nodes. Sterile, cell-free plasma from lymph collected during the 48 hr after the injections, induced vigorous lympho-proliferative responses in naive lymph nodes after s.c. injection into autochthonous or allogeneic recipients. The same lymph had an adjuvant action when injected i.p. into both nude and euthymic rats. Many samples of such lymph were screened for biological activity in rats by noting the increase in the weight of the regional popliteal nodes that occurred after the test sample had been injected into the footpad. All the active samples were shown, by atomic absorbance spectroscopy, to contain beryllium, and we concluded that this metal, in the form of soluble Be-protein adducts, was probably the prime mover in all the observed responses.