SOLID MATRIX-ANTIBODY-ANTIGEN COMPLEX CAN CLEAR VIREMIA AND ANTIGENEMIA IN PERSISTENT DUCK HEPATITIS-B VIRUS-INFECTION

One-day-old ducklings experimentally infected with duck hepatitis B vi rus (DHBV) were found to be immunologically tolerant to virus antigens (DHBsAg, DHBcAg), with no humoral or cellular immune responses being detected. When immunized with virus antigens in Freund's complete adju vant, no immune responses could be induced. Rabbit anti-DHBs sera were complexed to a solid matrix (Staphylococcus aureus Cowan A strain) an d purified DHBsAg was bound to this complex to form a solid matrix ant ibody-antigen (SMAA) complex. This SMAA was used as an immunogen to im munize the tolerant ducks. After three injections, in 12 of 17 ducks s erum DHBV DNA became absent and serum DHBsAg was cleared. In eight of 16 ducks, low titres of anti-DHBs could be detected. The SMAA approach shows potential for application in immunoregulatory treatment for chr onically infected hepatitis B patients.