EVIDENCE FOR A FUNDAMENTAL RELATIONSItlP BETWEEN HUMORAL AND CELL-MEDIATED I]~M-UNITY

In the preceding paper (1) some chemical, antigenic, and biological propert ies of a series of ace toace ty la ted derivat ives of Salmonella adelaide flagellin were described. Several chemical and antigenic tests revealed tha t as flagellin was ace toace ty la ted to increasing extents there was a s teady decline in the affinity of the molecule for anti-flagellin antibodies. This loss in antigenic ac t iv i ty appeared to be accompanied on the one hand by a reduced capac i ty to ini t ia te an t ibody formation bu t on the other hand b y an enhanced abi l i ty to induce an t ibody tolerance. In this paper the an t ibody tolerance induced by these ace toace ty la ted flagellins is s tudied in more detail . Fur thermore , the abi l i ty of these acetoacetyl der ivat ives to induce de layedtype hypersens i t iv i ty is reported. F rom these studies i t was found tha t suppression of an t ibody formation in adul t ra ts was accompanied by enhanced cel l-mediated immuni ty . In fact, i t appears tha t in adul t animals an t ibody format ion and cel l-mediated immuni ty m a y well be opposing immunological processes. By contrast , tolerance induced in neonatal ra ts by acetoacetyl flagellin existed a t the level of both humoral and cel l-mediated immuni ty . Some pre l iminary aspects of this work have been repor ted elsewhere. 1