EFFECT OF CARRIER PRIMING ON ANTIBODY AVIDITY IN INVIVO AND INVITRO IMMUNE-RESPONSE

  • 1 January 1977
    • journal article
    • research article
    • Vol. 32  (4) , 539-549
Abstract
The effect of carrier priming on antibody avidity was investigated under several experimental conditions. Mice were carrier primed with HRBC (horse red blood cells) prior to immunization with TNP (2,4,6-trinitrophenyl) conjugated to HRBC. Immunization was performed in vivo or in spleen cell culture, and avidity of anti-TNP antibodies was estimated from inhibition of direct PFC (plaque-forming cells) by free TNP-BSA (-bovine serum albumin). The data indicate the appropriate conditions under which carrier priming can enhance antibody avidity. The carrier effect is maximized by priming the animals with 104-105 HRBC 3-7 days before immunization with a low dose of TNP-HRBC. Hyperimmunization by repeated injections of a high dose of the conjugate does not modify the carrier effect on avidity but it delays the fall of avidity in carrier primed and unprimed animals. These results are interpreted in terms of T[thymus-derived]- and B[bone marrow-derived]-cell cooperation within the framework of the maturation theory of antibody affinity. Carrier priming increased the number of direct PFC of the Ig[immunoglobulin]M and, mostly, of the non-IgM classes; this implies that T cells can help IGM production and the shift to IgG.