On the mechanism of action of adjuvants.

Evidence is presented that one a way which adjuvants exert their effect is by initiating an enduring increase in the localization of labelled cells in draining lymphoid tissues. Agents not generally considered to be adjuvants (carbon, latex, sheep erythrocytes) but capable of altering lymphocyte recirculation are shown to prevent the induction of tolerance by soluble bovine gamma globulin (BGG). These properties fulfil the criteria for adjuvanticity as defined by Dresser (1968) and link the expression of adjuvanticity to alterations in lymphocyte circulation.