Cellular immune responsiveness in rabbits with Setaria digitata filarial antigen and TDM adjuvant.

The purified surface antigens of the bovine filarial parasite Setaria digitata were used as an antigen to immunize rabbits. The aqueous suspensions of trehalose 6-6' dimycolate (TDM) has been successfully used as an effective immunomodulator in experimental studies on filariasis. The effectiveness of such an antigen-TDM combination was demonstrated by enhanced humoral and cellular immunity. Administration of antigen alone shows only humoral immunity. The detectable cellular immune responses further confirm the effect of filarial antigen-TDM combination. The cell-mediated immunity was expressed in vivo by delayed skin reaction and in vitro by leukocyte and macrophage migration inhibition tests.