ANTICARRIER IMMUNITY SUPPRESSES THE ANTIBODY-RESPONSE TO POLYSACCHARIDE ANTIGENS AFTER INTRANASAL IMMUNIZATION WITH THE POLYSACCHARIDE-PROTEIN CONJUGATE

We have conjugated cholera toxin (CT) B subunit (CTB) to dextran and s tudied the effect in mice of previous immunization with CT and CTB on the response to dextran after intranasal immunizations with conjugate. Preexisting immunity to CTB was found to inhibit both the lung mucosa l response and serum antibody response to dextran, but this effect cou ld be overcome by using a higher dose of conjugate and delaying the co njugate immunization until the CTB antibody titers had declined, The r ole of anti-CTB antibodies on the mucosal surface was probably to prev ent uptake of the conjugate through a mechanism of immune exclusion. P assively transferred serum antibodies against CTB, on the other hand, suppressed both the serum response and the local antibody response aga inst CTB but did not affect the response to dextran after intranasal i mmunization with conjugate.